Method and apparatus for controlling the flow rate of reactants

Abstract

The present invention relates to a method and apparatus for controlling the feed rate of at least one reactant in a methanation process. In particular, the present invention relates to a method and apparatus for iteratively controlling the feed rate of at least one reactant in a methanation process carried out in a reactor, such as an industrial-sized reactor and / or a reactor assembly according to the present invention. More specifically, the present invention refers to a method and apparatus for iteratively controlling the feed rate of at least one reactant in a methanation process in an aqueous culture medium containing a biocatalyst such as an archaea.

Description

[Technical Field]

[0001] The present invention relates to a method and apparatus for controlling the feed rate of at least one reactant in a methanation process. In particular, the present invention relates to a method and apparatus for iteratively controlling the feed rate of at least one reactant in a methanation process carried out in a reactor, such as an industrial-sized reactor and / or a reactor assembly according to the present invention. More specifically, the present invention refers to a method and apparatus for iteratively controlling the feed rate of at least one reactant in a methanation process in an aqueous culture medium containing a biocatalyst such as an archaea.

[0002] The methanation process of the present invention may be the methanation of carbon monoxide CO + 3H2 → CH4 + H2O or the methanation of carbon dioxide CO2 + 4H2 → CH4 + 2H2O. The methanation process of the present invention is carried out in a reactor and produces a product gas by using a feed gas. For example, in the case of methanation of carbon monoxide, the feed gas contains carbon monoxide and dihydrogen. In the case of methanation of carbon dioxide, the feed gas contains carbon dioxide and dihydrogen. The product gas contains methane. The product gas may further contain carbon oxides and / or dihydrogen. [Background technology]

[0003] Methane has the highest energy density per carbon atom among volatile hydrocarbons, and its potential for energy conversion is far greater than that of other natural gases. Therefore, methane constitutes a sustainable and renewable energy source and is already replacing coal and other fossil fuels. Consequently, the methane process is increasingly being used in the production of sustainable and renewable energy.

[0004] In this case, it is beneficial to maximize the amount of methane in the product gas and / or minimize the amount of carbon oxides and / or dihydrogen in the product gas. In particular, the amount of carbon oxides and / or dihydrogen in the product gas produced through the methanation process should be maintained within a given limit. Therefore, in the above technical field, it is necessary to maximize the amount of methane produced in the methanation process and / or minimize the amount of carbon oxides and / or dihydrogen in the product gas of the methanation process.

[0005] Methods for controlling the feed rate of reactants in a methanation process are known in the art described above. These methods aim to improve the quality of the product gas by reducing excess feed rates of reactants and / or increasing the amount of methane produced in the methanation process. Known control methods rely on direct measurement of the feed rate of reactants. Typically, the measurements used in the art described above are characterized by a relatively low signal-to-noise ratio, which negatively affects the accuracy of the measurement and thereby limits the efficiency of the known control methods.

[0006] For example, the deviation between the measured value of the reactant feed flow rate and the amount of reactant actually supplied to the reactor can result from measurement uncertainties, unexpected and / or undetectable fluctuations in the composition of the reaction's feed gas, and / or inaccurate positioning of means for controlling the feed gas flow rate (e.g., control valves).

[0007] Furthermore, the methanation process produces water, which is typically drained through the reactor drain to prevent liquid buildup in the reactor. The production of water and subsequent drainage from the reactor result in continuous dilution and flushing of the solute. This flushing is supplemented by chemical dosing, for example, by adding appropriate additive compounds to the reactor. Since the kinetics of the effects of chemical dosing are typically slower than the ramping capacity of the process, any change in the dosing rate tends to have a delaying effect on the methanation process, which affects the degree of methanation. [Overview of the project]

[0008] At least some of these problems are at least partially solved by the inventions of this application relating to the computer implementation method described in claim 1, the data processing system described in claim 12, the computer program product described in claim 14, and the computer-readable storage medium described in claim 15. Embodiments of the present invention are the subject matter of the dependent claims.

[0009] In particular, the present invention makes it possible to monitor the degree of the methane process and control the amount and ratio of reactants to maintain good quality in the product stream with minimal amounts of unreacted reactants. In this way, conditions in the reactor suitable for catalytic action of the reaction are maintained, and the development of the reaction capacity in the reactor is supported.

[0010] Throughout this specification, the following conventions are used. • Indices C, H, and M refer to carbon oxides, dihydrogen, and methane, respectively; • Indices F and P refer to the feed gas and product gas, respectively; The suffixes "req," "mea," "est," and "sp" refer to the requested value, measured value, estimated value, and set value of a quantity, respectively; · Expression Q R (R=C,H) refers to the supply flow rate of reactant R; Equation b represents the molar ratio of the supply flow rate of dihydrogen in the supply gas to the supply flow rate of carbon oxide in the supply gas, i.e., b = Q H / Q C That is the case.

[0011] Furthermore, equation x R,D(R=C,H,M and D=F,P) refers to the amount of compound R in the feed gas relative to the feed gas (when D=F) or the amount of compound R in the product gas relative to the product gas (when D=P). In particular, the above amounts are expressed as mole percentages (mol:mol) of the feed gas (when D=F) or product gas (when D=P). The mole percentage may also be relative to the equivalent dry gas, i.e., the water vapor fraction is excluded from the feed gas (when D=F) or product gas (when D=P).

[0012] A first aspect of the present invention relates to a computer implementation method for iteratively controlling the feed flow rate of a first reactant in a methanation process within a reactor. The methanation process is carried out within a reactor and generates a product gas by using a feed gas, the feed gas containing a first reactant and a second reactant.

[0013] According to the present invention, the first reactant is one of dihydrogen and a carbon oxide, and the second reactant is the other of dihydrogen and a carbon oxide. For example, the first reactant is dihydrogen and the second reactant is a carbon oxide, such as carbon monoxide or carbon dioxide. Alternatively, the first reactant is a carbon oxide, such as carbon monoxide or carbon dioxide, and the second reactant is dihydrogen. In particular, the product gas includes, for example, methane. The product gas may further include dihydrogen and / or a carbon oxide, such as carbon monoxide and / or carbon dioxide.

[0014] The method according to the present invention includes at least the following steps: - A step of starting the calculation of a first set value for the supply flow rate of the first reactant, - A step of starting to modify the supply flow rate of the first reactant according to a first set value of the supply flow rate of the first reactant.

[0015] The calculation of the first setpoint for the supply flow rate of the first reactant is performed using first information, which indicates whether the estimated first difference between the estimated supply flow rate ratio in the first control iteration and the first required supply flow rate ratio in the first control iteration is positive or negative.

[0016] The feed rate ratio is the ratio between the feed rate of the first reactant and the feed rate of the second reactant, and the first information is generated by using a first set of measured physical quantities of the product gas.

[0017] The first set of measured physical quantities represents the ratio between the first value of the amount of carbon oxide in the product gas in the first controlled iteration and the first value of the amount of methane in the product gas in the first controlled iteration.

[0018] The reactor may be included in an industrial plant, such as an industrial power plant. The first and second reactants may be supplied together to the reactor via a gas supply. Alternatively, or in conjunction with the above, dihydrogen and carbon oxides may be supplied separately to the reactor, for example, via a first and second gas supply, respectively. In particular, dihydrogen is preferably produced from H2O in the reactor by a suitable electrolytic reaction using electrical energy. For example, the electrical energy may be produced by a renewable energy source. Carbon oxides, such as carbon monoxide or carbon dioxide, may be produced in the biogas reactor and / or industrial gas waste. In particular, the reactor may include an aqueous culture medium containing suitable methane-producing microorganisms, such as archaea, for converting the feed gas into product gases.

[0019] In particular, the second reactant is the so-called leading reactant. The first reactant is determined by using the second reactant and the feed rate ratio. The leading reactant may depend on the plant configuration and / or operating objectives. For example, if the method of carbon oxide production (e.g., amine or water scrubbing, reversible absorption, membrane separation, freeze-drying) imposes constraints on the amount of carbon oxide that can be supplied to the reactor, then carbon oxide is the leading reactant. Alternatively, if the operating objective is to process a given flow of dihydrogen, set by, for example, the amount of energy available for the electrolytic reaction, then dihydrogen is identified as the leading reactant.

[0020] A method for iteratively controlling the supply flow rate of the first reactant may include multiple control iterations. Each of these control iterations may be associated with its own time interval. For example, the first and second iterations (described later) are associated with the first and second time intervals, respectively. For example, the first time interval does not overlap with the second time interval and precedes it in time. In particular, the multiple control iterations include an initial control iteration. The set value of the supply flow rate ratio in the initial control iteration may be equal to the required value of the supply flow rate ratio in the initial control iteration.

[0021] In particular, each element of the first set of measured quantities is measured at a point in time of the first time interval, which is the measured value of the physical quantity of the product gas at the first iteration, i.e., the aforementioned point in time. Below, quantities related to the first controlled iteration may be shown to be dependent on time t1. Quantities shown to be dependent on time t1 are, in particular, quantities estimated, measured, and / or calculated in the first controlled iteration, but which do not necessarily have to be at time t1.

[0022] In particular, the first set of measurements includes, for example, physical quantities that enable the estimation of a ratio (hereinafter also referred to as the "first ratio") between a first value of the amount of carbon oxide in the product gas in the first controlled iteration and a first value of the amount of methane in the product gas in the first controlled iteration. For example, the first set of measurements includes, for example, a first measurement of the first ratio.

[0023] For example, the first set of measurements is the first measured value of the amount of carbon oxide in the product gas in the first controlled iteration.

number

number

number

[0024] Alternatively, or in conjunction with the above, the first set of measurements is the first measured value of the amount of carbon oxide relative to the product gas in the first iteration.

number

number

number

[0025] For example, the first piece of information may represent an estimate of the first difference. For example, the first piece of information may be encoded into an estimate of the first difference. In particular, the estimate of the first difference

number

number

[0026] First estimated value b of the supply flow rate ratio est (t1) is expressed with respect to at least a first set of measured physical quantities. In particular, the first estimate of the supply-flow ratio is calculated using at least some of the elements of the first set of measured quantities and a suitable formula based on, for example, the stoichiometry of the methane process. For example, the first estimate of the supply-flow ratio formula may be given by:

number

[0027] The coefficient ρ depends on the methane process. For methane production of carbon dioxide, ρ=4, and for methane production of carbon monoxide, ρ=3. In particular, the above formula is used when the amount of methane in the feed gas is small or zero, and the amount of hydrogen in the product gas is small or zero. For example, the amount of methane in the feed gas is:

number

number

[0028] For example, the first estimate of the supply flow ratio equation can be given by:

number

[0029] In particular, equation (3) above is used when the supply gas is essentially composed of carbon oxides, methane, and dihydrogen. Specifically, this is used when the amount of compounds other than carbon oxides, methane, and hydrogen in the product gas is

number

[0030] In this invention, the estimated feed flow ratio is calculated by using measurements performed on the product gas. The use of these measurements has a relatively high signal-to-noise ratio, which leads to a more accurate estimation of the observed feed flow ratio and, consequently, more precise control of the methane process. The feed flow ratio estimate of this invention provides a real-time estimate of the actual ratio of reactants in the feed gas and thus estimates in real time the deviation between the required feed flow ratio and the actual value of the feed flow ratio entering the reactor.

[0031] According to one embodiment of the present invention, the calculation of a first set value for the supply flow rate of the first reactant is performed according to a first set value for the supply flow rate ratio. In particular, according to the first information, if the estimated value of the first difference is positive, the first set value for the supply flow rate ratio is lower than the second required value for the supply flow rate ratio, and according to the first information, if the estimated value of the first difference is negative, the first set value for the supply flow rate ratio is greater than the second required value for the supply flow rate ratio. The second required value for the supply flow rate ratio is, in particular, the required value for the supply flow rate ratio in the second control iteration, and the first control iteration precedes the second control iteration in time. For example, the second control iteration is the iteration immediately following the first control iteration. In particular, according to the first information, if the estimated value of the first difference disappears, the first set value for the supply flow rate ratio becomes equal to the second required value for the supply flow rate ratio.

[0032] The first setpoint for the feed rate of the first reactant is, in particular, the setpoint for the feed rate of the first reactant in the second control iteration. For example, the calculation of the first setpoint for the feed rate of the first reactant is performed by using the second value for the feed rate of the second reactant. The second value for the feed rate of the second reactant may be a measured value, estimated value, required value, and / or setpoint for the feed rate of the second reactant. For example, the second value for the feed rate of the second reactant is the setpoint for the feed rate of the second reactant in the second control iteration, and / or the required value for the feed rate of the second reactant in the second control iteration.

[0033] In the following, quantities related to the second control iteration are shown to be dependent on time t2. Quantities shown to be dependent on time t2 are, in particular, quantities estimated, measured, and / or calculated in the second control iteration, but not necessarily at time t2. For example, when the first reactant is dihydrogen, for instance, when carbon oxide is the main reactant, the first set value of the feed flow rate of the first reactant.

number

number

[0034] When the first reactant is a carbon oxide, for example, when dihydrogen is the main reactant, the first set value of the supply flow rate of the first reactant [Number] may satisfy the following equation:<00,00442> [Number] Here, [Number] is the second value of the supply flow rate of the second reactant. In particular, when the first reactant is a carbon oxide, the calculation of the first set value of the supply flow rate of the first reactant can be done by using Equation (5).

[0035] The first required value b req (t1) of the supply flow rate ratio is, in particular, the value of the supply flow rate ratio required and / or set by the operator of the plant's reactor in the first control iteration. Alternatively, the first required value of the supply flow rate ratio may be estimated by using a required value of a quantity, such as the degree of the methanation process, and the above required value is the value required by the operator in the first control iteration.

[0036] The second required value b req(t2) may be the value of the supply flow rate ratio requested and / or set by the operator in the second control iteration. Alternatively, the second required value of the supply flow rate ratio may be estimated by using a required value of a quantity, such as the degree of the methane process, which is the value requested and / or set by the operator in the second control iteration.

[0037] According to the present invention, the step of initiating the modification of the reactant supply flow rate according to a set value of the supply flow rate may include transmitting the set value to a computing device in the reactor and / or power plant. In particular, the computing device controls a valve in the reactor or power plant, and the valve adjusts the supply flow rate of the reactant to the reactor. In particular, this step may be performed by modifying the supply flow rate of the reactant according to a set value of the supply flow rate. For example, modifying the supply flow rate of the reactant according to a set value of the supply flow rate may include controlling a valve in the reactor or power plant, and the valve adjusts the supply flow rate of the reactant to the reactor. For example, the valve is controlled to adjust the supply flow rate of the reactant according to a set value of the supply flow rate of the reactant.

[0038] According to one embodiment of the method of the present invention, calculating a first setpoint for the supply flow rate of the first reactant includes calculating a first value of the first function f b In particular, the estimated supply flow rate ratio b est and the requested supply flow rate ratio b req The increasing function f of the difference between the two. b =f b (b est -b req ) In particular, the first value of the first function is the value of the first function in the first difference estimate, that is, the first value f of the first function b,1 teeth,

number

[0039] In particular, when the first reactant is dihydrogen, the first set value of the supply flow rate of the first reactant is a decreasing function of the first value of the first function, and when the first reactant is a carbon oxide, the first set value of the supply flow rate of the first reactant is an increasing function of the first value of the first function.

[0040] For example, if the first reactant is dihydrogen, the first set value of the supply flow rate of the first reactant is proportional to the second required value of the supply flow rate ratio, and if the first reactant is a carbon oxide, the first set value of the supply flow rate of the first reactant is inversely proportional to the second required value of the supply flow rate ratio. In particular, in this embodiment, at least a portion of the first information is encoded into a first value of the first function.

[0041] For example, the first set value b of the supply flow rate ratio sp (t2) may also be a decreasing function of the first linear combination, for example:

number

[0042] In particular, the first set value b of the supply flow rate ratio sp (t2) may be inversely proportional to the first linear combination λ1, or it may have hyperbolic dependence on λ1, for example:

number

[0043] The first linear combination may contain a first term, the first term of the first linear combination being the first value f of the first function. b,1 It is equal to the product of and the first positive coefficient c1.

[0044] For example, for each control iteration, the first function represents the difference between the estimated supply flow rate ratio and the requested supply flow rate ratio in the iteration, and the first function is an increasing function of the difference. In particular, the first value of the first function is equal to the value of the first function in the first estimated difference, and represents the difference between the estimated supply flow rate ratio and the requested supply flow rate ratio in the first iteration.

[0045] In this embodiment, the set value of the supply flow rate ratio is less sensitive to multiplicative or additive biases that may affect the control of the supply flow rates of the first and / or second reactants. In this way, the accuracy of calculating the first set value of the supply flow rate of the first reactant is improved.

[0046] According to the present invention, an increasing function of a variable is, in particular, a function that does not decrease as the variable increases. Furthermore, a decreasing function of a variable is, in particular, a function that does not increase as the variable increases.

[0047] In particular, the first value of the first function is equal to zero if the estimated supply flow ratio is equal to the required supply flow ratio, positive if the estimated supply flow ratio is greater than the required supply flow ratio, and negative if the estimated supply flow ratio is less than the required supply flow ratio.

[0048] For example, the first function may be the difference between the estimated supply flow ratio and the required supply flow ratio. In particular, the first function may be the estimated supply flow ratio b req The function may be a decreasing function, for example, the following:

number

[0049] In this case, the first value of the first function is,

number

[0050] According to one embodiment of the present invention, calculating a first setpoint for the feed rate of the first reactant includes calculating an estimate of the time derivative of the first function in a first control iteration. The estimate of the time derivative of the first function is calculated by using a first set of measured quantities. In particular, when the first reactant is dihydrogen, the first setpoint for the feed rate of the first reactant is an increasing function of the estimate of the time derivative of the first function in the first control iteration, and when the first reactant is a carbon oxide, the first setpoint for the feed rate of the first reactant is a decreasing function of the estimate of the time derivative of the first function in the first control iteration.

[0051] Alternatively, or in conjunction with the above, calculating a first setpoint for the feed rate of the first reactant involves calculating an estimate of the time integral of the first function in the first control iteration. The estimate of the time integral of the first function is calculated by using a first set of measurements. In particular, if the first reactant is dihydrogen, the first setpoint for the feed rate of the first reactant is a decreasing function of the estimate of the time integral of the first function, and if the first reactant is a carbon oxide, the first setpoint for the feed rate of the first reactant is an increasing function of the estimate of the time integral of the first function.

[0052] For example, the first linear combination may include a second term, the second term of the first linear combination being an estimate D of the time derivative of the first function in the first controlled iteration. b,1 It is equal to the product of with the second negative coefficient c². The first linear combination may include a third term, the third term of the first linear combination is the estimate I of the time integral of the first function in the first controlled iteration. b,1 It is equal to the product of and the third positive coefficient c3.

[0053] For example, the first linear combination can be equal to the following:

number

[0054] The first coefficient c1 can be in the range of 0.3 to 0.7, especially 0.4 to 0.6. For example, the second coefficient c2 can be in the range of 0.3 min to 0.7 min, especially 0.4 min to 0.6 min. The third coefficient c3 can be in the range of 2.0 min. -1 ~3.0min -1 , especially 2.2 min -1 ~2.7min -1 It can be included in this.

[0055] Estimated value D of the time derivative of the first function in the first control iteration b,1 This is, in particular, an estimate of the value of the time derivative of the first function at a point in time included in the first time interval. For example, the estimate D b,1 This can be calculated numerically by using the first value of the first function.

[0056] Estimated value I of the time integral of the first function in the first controlled iteration b,1 This is, in particular, an estimate of the time integral of the first function at a point in time included in the first time interval. For example, the estimate I b,1 This can be calculated numerically by using the first value of the first function.

[0057] The first value f of the first function b,1 is, b est It is calculated using (t1), which is expressed with respect to the first set of measured quantities. Thus, in this case, the estimated value D b,1 and / or I b,1 This is calculated by using a first set of measured quantities.

[0058] Estimated value I b,1 It has little dependence on noise that may affect the measured quantity. This is because the expected value of this noise is almost zero. Furthermore, the estimated value I b,1 This includes information about the value of the first function in the control iteration that temporally precedes the first control iteration. Therefore, ultimately, the estimated value I b,1This includes information about the history of the difference between the estimated supply flow ratio and the requested supply flow ratio, and is more stable against instantaneous fluctuations in this difference. Estimated value I in the calculation of the first setpoint of the supply flow ratio b,1 The use of this method therefore stabilizes the calculation of the above settings and / or improves their robustness.

[0059] Estimated value D of the time derivative of the first function b,1 This considers the rate of variation of the first function. D b,1 The dependence of the first setpoint of the feed flow rate of the first reactant on the first reactant reduces the overshoot of the feed flow rate of the first reactant. In this way, the deviation between the value of the feed flow rate of the first reactant and the required value of the feed flow rate is reduced. Therefore, the methane process operates at substantially the required operating point, thereby increasing the predictability of the process results.

[0060] One embodiment of the present invention further includes the following steps: - A step of starting the calculation of a second setpoint for the supply flow rate of the second reactant, wherein the calculation of the second setpoint for the supply flow rate of the second reactant is performed by using at least a first setpoint for the supply flow rate of the second reactant and the ramping rate of the supply flow rate of the second reactant, and - A step of starting to modify the supply flow rate of the second reactant according to a second set value for the supply flow rate of the second reactant.

[0061] If the first set value for the supply flow rate of the second reactant is greater than the first required value for the supply flow rate of the second reactant, the second set value for the supply flow rate of the second reactant is less than the first set value. Conversely, if the first set value for the supply flow rate of the second reactant is less than the first required value for the supply flow rate of the second reactant, the second set value for the supply flow rate of the second reactant is greater than the first set value for the supply flow rate of the second reactant.

[0062] In particular, if the first set value of the supply flow rate of the second reactant is equal to the first required value of the supply flow rate of the second reactant, then the second set value of the supply flow rate of the second reactant is equal to the first set value of the supply flow rate of the second reactant.

[0063] The first set value of the supply flow rate of the second reactant is, in particular, the set value of the supply flow rate of the second reactant in the first control iteration.

number

number

number

[0064] For example, the second set value of the supply flow rate of the second reactant.

number

number

[0065] In this embodiment, the supply flow rate of the second reactant is changed in steps to reduce the difference between the set value and the required value of the supply flow rate of the second reactant. This stepwise adjustment of the set value prevents a decrease in the amount of gas available for conversion to methane-producing microorganisms in the culture medium.

[0066] One embodiment of the method of the present invention includes the step of initiating a modification of the supply flow rate of a second reactant according to a set value of the supply flow rate of a second reactant, wherein the set value of the supply flow rate of the second reactant is equal to a first required value of the supply flow rate of the second reactant.

[0067] In one embodiment of the present invention, the calculation of a first setpoint for the supply flow rate of the first reactant is performed by using second information, the second information indicating whether the estimated second difference between the estimated degree of the methane process in the first control iteration and the required degree of the methane process in the first control iteration is positive or negative.

[0068] For example, the second piece of information may represent an estimate of the second difference. For example, the second piece of information may be encoded into an estimate of the second difference. In particular, the estimate of the second difference

number

number

[0069] First estimate of the degree of the methane process y est (t1) is expressed with respect to at least a first set of measured physical quantities. In particular, y est (t1) is calculated by using at least some of the elements of a first set of measurements and a suitable formula based on, for example, the stoichiometry of the methanation process. For example, an estimate of the degree of the methanation process can be given by:

number

[0070] In particular, the above formula is used when the amount of methane in the supply gas is small or zero.

[0071] The estimated supply flow rate ratio is calculated using measurements taken on the product gas. The use of these measurements has a relatively high signal-to-noise ratio, which leads to a more accurate estimation of the observed degree of the methane process and, consequently, more precise control of the methane process.

[0072] Further embodiments of the present invention include the following steps: - A step of starting the calculation of a third setpoint for the supply flow rate of the second reactant, wherein the calculation of the third setpoint for the supply flow rate of the second reactant is performed by using a first reference value and a first value for the supply flow rate of the second reactant in the first control iteration, and - A step of starting to modify the supply flow rate of the second reactant according to a third set value for the supply flow rate of the second reactant.

[0073] The third set value for the supply flow rate of the second reactant is equal to the minimum value between the second reference value and the first value for the supply flow rate of the second reactant in the second controlled iteration.

[0074] In particular, if the estimated value of the second difference is positive according to the second piece of information, the second reference value for the supply flow rate of the second reactant is greater than the first reference value for the supply flow rate of the second reactant, and if the estimated value of the second difference is negative according to the second piece of information, the second reference value for the supply flow rate of the second reactant is less than the first reference value for the supply flow rate of the second reactant.

[0075] In particular, if the second difference estimate disappears according to the second piece of information, the second reference value for the supply flow rate of the second reactant becomes equal to the first reference value for the supply flow rate of the second reactant.

[0076] The third set value for the supply flow rate of the second reactant may be the set value for the supply flow rate of the second reactant in the second control iteration. In particular, the second reference value for the supply flow rate of the second reactant is the upper limit in the second control iteration relative to the third set value for the supply flow rate of the second reactant. Furthermore, the first reference value for the supply flow rate of the second reactant may be the upper limit in the first control iteration relative to the set value for the supply flow rate of the second reactant in the first control iteration.

[0077] The third setpoint for the feed rate of the second reactant depends on whether the estimated process is lower than the required process, i.e., the process capacity is limited, or whether the estimated process is higher than the required process, i.e., the process capacity is not limited. In this embodiment, the third setpoint for the feed rate of the second reactant is adjusted according to the discrepancy between the estimated and required process, so that the feed rate of the most soluble reactant is maintained higher than the required feed rate, and / or the amount of dihydrogen in the product gas is reduced. The feed rate of the second reactant converges toward a flow that matches the current capacity of the process. Furthermore, in situations where the reaction capacity is limited, the setpoint for the main reactant is limited according to the current conversion capacity of the process until the required capacity is recovered or reached. In this way, adverse effects resulting from fluctuations in catalyst performance and / or process conditions (e.g., temperature, excess reactant, additive dosing) are mitigated, and / or the recovery of process performance is accelerated.

[0078] For example, the third set value of the supply flow rate of the second reactant.

number

number

number

number

[0079] The degree of the methane process is defined, in particular, as the ratio between the amount of carbon oxides in the feed gas converted to methane and the amount of carbon oxides in the feed gas. The required degree of the methane process is, in particular, the value requested and / or set by the operator in the first control loop.

[0080] The first value of the second reactant feed rate may be the first requested value of the second reactant feed rate in the second control iteration. The first value of the second reactant feed rate is, in particular, the value of the second reactant feed rate requested and / or set by the plant reactor operator in the second control iteration.

[0081] According to one embodiment of the present invention, the first value of the supply flow rate of the second reactant is a function of the first set value of the supply flow rate of the second reactant, the first required value of the supply flow rate of the second reactant, and the ramping rate of the supply flow rate of the second reactant.

[0082] In particular, if the first set value of the supply flow rate of the second reactant is greater than the first required value of the supply flow rate of the second reactant, then the first value of the supply flow rate of the second reactant is less than the first set value of the supply flow rate of the second reactant. Conversely, if the first set value of the supply flow rate of the second reactant is less than the first required value of the supply flow rate of the second reactant, then the first value of the supply flow rate of the second reactant is greater than the first set value of the supply flow rate of the second reactant.

[0083] In particular, if the first set value of the supply flow rate of the second reactant is equal to the first required value of the supply flow rate of the second reactant, then the first value of the supply flow rate of the second reactant will be equal to the first set value of the supply flow rate of the second reactant. For example, the first value of the supply flow rate of the second reactant

number

[0084] According to one embodiment of the present invention, calculating a first set value for the supply flow rate of the first reactant includes calculating a first value of the second function f y In particular, the estimated degree of the methane process y est and the degree of the standard for the methane process y req It is an increasing function of the difference between and , for example, f y =f y (y est -y req Furthermore, the first value of the second function is f y,1 f is the value of the second function in the second difference estimate, i.e., the first value of the first function. y,1 teeth,

number

[0085] For example, the second reference value for the supply flow rate of the second reactant.

number

number

number

[0086] The second linear combination includes the first term, the first term of the second linear combination being equal to the product of the first value of the second function and a positive fourth coefficient c4. The fourth coefficient may depend on the sign of the difference between the estimated degree of the methane process and the required degree of the methane process.

[0087] For example, for each controlled iteration, the second function represents the difference between the estimated degree of the methane process in the iteration and the required degree of the methane process in the iteration, and the second function is an increasing function of the difference. In particular, the first value of the second function is equal to the value of the second function in the second difference, and represents the difference between the estimated degree of the methane process in the first iteration and the required degree of the methane process in the first iteration.

[0088] In particular, the reference value for the feed flow rate of the second reactant constitutes an upper limit for this feed flow rate setpoint, making it possible to maintain the setpoint for the feed flow rate of the second reactant within a range that provides a process conversion capability close to the observed conversion capability. In this embodiment, in the second control iteration, the feed flow rate reference value is updated by using the feed flow rate reference value from the first control iteration. The update of the reference value also depends on information indicating the sign of the difference between the estimated and required levels of the process, i.e., whether the process capability is limited. Thus, the update of the reference value typically takes into account the fact that the amplitude of the variation in the difference between the estimated and required levels of the process depends on whether the process capability is limited. In particular, since the system usually operates at a relatively high level, e.g., above 90%, the variation in the difference between the estimated and required levels of the process when the process capability is limited is larger than the variation in the above difference when the process capability is not limited.

[0089] In particular, the first value of the second function is equal to zero if the estimate of the second difference vanishes, is positive if the estimate of the second difference is positive, and is negative if the estimate of the second difference is negative.

[0090] For example, the second function may be the difference between the estimated degree of the methanation process and the required degree of the methanation process. In particular, the second function may be a function y of the required degree of the methanation process. req For example, it may be a decreasing function, such as the following:

number

[0091] In this case, the first value of the second function is,

number

[0092] According to one embodiment of the present invention, calculating a first setpoint for the feed rate of the first reactant includes calculating an estimate of the time derivative of a second function in a first control iteration, the estimate of the time derivative of the second function is calculated by using a first set of measured quantities. In particular, the second reference value for the feed rate of the second reactant may be an increasing function of the estimate of the time derivative of the second function.

[0093] Alternatively, or in conjunction with the above, calculating a first setpoint for the feed rate of the first reactant may include calculating an estimate of the time integral of the second function in the first control iteration. The estimate of the time integral of the second function is calculated using a first set of measurements. For example, the second baseline for the feed rate of the second reactant may be an increasing function of the estimate of the time integral of the second function in the first control iteration.

[0094] For example, the second linear combination may include a second term, the second term being an estimate of the time derivative D of the second function. y,1 It is equal to the product of and the fifth coefficient c5. The fifth coefficient depends on the sign of the difference between the estimated degree of the methane process and the required degree of the methane process. For example, the second linear combination may include a third term, the above third term being the estimated time integral I of the second function. y,1 It is equal to the product of the sixth coefficient c6. The sixth coefficient depends on the sign of the difference between the estimated degree of the methane process and the required degree of the methane process.

[0095] For example, the second linear combination may be equal to the following:

number

[0096] The fourth coefficient is the first value f of the first function. y,1 It may depend on, for example,

number

number

number

number

number

number

[0097] Estimated value I y,1It has little dependence on noise that may affect the measured quantity. This is because the expected value of this noise is almost zero. Furthermore, the estimated value I y,1 This includes information about the value of the second function in a control iteration that temporally precedes the first control iteration. Therefore, ultimately, the estimated value I y,1 This includes information about the history of the difference between the estimated and required levels of the process, and is more stable against instantaneous fluctuations in this difference. Estimated value I in the calculation of the second reference value for the second reactant feed flow rate y,1 The use of therefore stabilizes and / or improves the robustness of the calculation of the above setting value. Estimated time derivative D of the second function y,1 This considers the rate of change of the second function. D y,1 The dependence of the second reference value on the supply flow rate of the second reactant reduces the overshoot of the reference value of the supply flow rate of the second reactant, thereby reducing the deviation between the first and second reference values ​​of the supply flow rate of the second reactant.

[0098] Estimated value D y,1 This is, in particular, an estimate of the value of the time derivative of the second function at a point in time included in the first time interval. For example, the estimate D y,1 This can be calculated numerically by using the first value of the second function. Estimated value I y,1 This is, in particular, an estimate of the time integral of the second function at a point in time included in the first time interval. For example, the estimate I y,1 This can be calculated numerically by using the first value of the second function. The first value of the second function is f y,1 y is expressed with respect to the first set of measured quantities. est It is calculated by using (t1). Therefore, in this case, the estimated value D y,1 and / or I y,1 This is calculated by using a first set of measured quantities.

[0099] According to one embodiment of the present invention, calculating a first set value for the supply flow rate of the first reactant includes calculating a first value of a third function gy is the estimated degree y of the methanation process est and the required degree y of the methanation process req and the increasing function g of the difference therebetween y = g y (y est - y req ). In particular, the first value of the third function is the value of the third function at the second difference. For example, the first value g y,1 of the third function is [Number] and so on. The second required value of the supply flow ratio may be proportional to the decreasing function of the first required value of the supply flow ratio and the first value of the third function.

[0100] In particular, when the first reactant is dihydrogen, the first set value of the supply flow rate of the first reactant is a decreasing function of the first value of the third function, and when the first reactant is a carbon oxide, the first set value of the supply flow rate of the first reactant is an increasing function of the first value of the third function.

[0101] For example, the dependence of the second required value of the supply flow ratio on the first required value of the supply flow rate and the first value of the third function of the supply flow ratio is such that the second required value of the supply flow ratio is between the minimum value b min and the minimum value b max . b min and b max The actual values of depend on the characteristics of the reactor and / or power plant. Typically, in the case of the methanation process, b min and b max may be equal to 4 and 4.2, respectively.

[0102] For example, the second required value b req (t2) of the supply flow ratio may be directly proportional to the third linear combination λ3, for example, as follows:<着号 <着号 [Number]<着号 <着号 ;<着号 <着号 <着号动

[0103] <着号 The third linear combination may include the first term, and the first term of the third linear combination is the first value g of the third function. y,1 It is equal to the product of and the seventh coefficient c7.

[0104] For example, for each control iteration, the third function represents the difference between the estimated supply flow rate ratio in the iteration and the required supply flow rate ratio in the iteration, and the third function is an increasing function of the difference. In particular, the first value of the third function is equal to the value of the third function in the second difference, and represents the difference between the estimated degree of the methane process in the first iteration and the required degree of the methane process in the first iteration.

[0105] In this embodiment, the required feed rate ratio in the second control iteration is adjusted in real time with respect to the required feed rate ratio in the first control iteration so that the amount of reactant supplied to the medium does not exceed the medium's conversion capacity. Furthermore, if the capacity of the methanation process is not limited, this embodiment allows for a reduction in the ratio between the feed rate of dihydrogen and the feed rate of carbon oxide, thereby reducing excess less soluble reactant. If the capacity of the methanation process is limited, the above ratio is increased to increase the amount of less soluble reactant in the reactor. An increase in less soluble reactant results in an increase in the amount of reactant that can react to produce methanation, thereby increasing the degree of methanation. Furthermore, an increase in less soluble reactant allows for a reduction in the amount of carbon oxide that does not enter the methanation process and accumulates in the reactor.

[0106] For example, the third function may be the difference between the estimated degree of the methane process and the required degree of the methane process. In particular, the third function may be y req The function could be, for example, the following:

number

[0107] Term g0 is, g y,1This is a bias that prevents an increase in the second required value of the supply flow rate ratio when the value of is small. For example, g0 = (1-y req ) / 2.

[0108] In one embodiment of the present invention, calculating a first setpoint for the feed rate of the first reactant includes calculating an estimate of the time derivative of a third function in a first control iteration, the estimate of the time derivative of the third function is calculated by using a first set of measured quantities. In particular, when the first reactant is dihydrogen, the first setpoint for the feed rate of the first reactant is a decreasing function of the estimate of the time derivative of the third function, and when the first reactant is a carbon oxide, the first setpoint for the feed rate of the first reactant is an increasing function of the estimate of the time derivative of the third function.

[0109] Alternatively, or in conjunction with the above, calculating a first setpoint for the feed rate of the first reactant may include calculating an estimate of the time integral of the third function in the first control iteration, which is calculated by using a first set of measurements. In particular, when the first reactant is dihydrogen, the first setpoint for the feed rate of the first reactant is a decreasing function of the estimate of the time integral of the third function, and when the first reactant is a carbon oxide, the first setpoint for the feed rate of the first reactant is an increasing function of the estimate of the time integral of the third function.

[0110] For example, the third linear combination may include the second term, which is an estimate of the time derivative of the third function.

number

number

[0111] For example, the third linear combination may be equal to the following:

Number

[0112] Coefficient α3 depends on g via the coefficient

Number

Number

Number

Number

[0113] The seventh coefficient c7 may be included in the range of -510 to -490, particularly -505 to -495. In particular, the fifth and / or sixth coefficients may be expressed in terms of the seventh coefficient,

Number

Number

Number

[0114] Estimated value

number

number

number

number

number

number

[0115] Estimated value

number

number

[0116] In one embodiment of the present invention, calculating the first setpoint of the supply flow rate of the first reactant includes generating second information by using a first set of measured physical quantities.

[0117] In particular, generating the second information includes calculating an estimated value of a second difference, for example, via Equation (10), by using the first set of measured physical quantities. For example, calculating the estimated value of the second difference may include calculating an estimated value of the degree of the methanation process by using the first set of measured physical quantities. For example, the estimated value of the degree of the methanation process is calculated by using Equation (11) above and / or Equation (24) below.

[0118] In a further embodiment of the present invention, calculating the first setpoint of the supply flow rate of the first reactant includes calculating a second reference value of the supply flow rate of the second reactant, and calculating the second reference value of the supply flow rate of the second reactant is performed by using a first reference value of the supply flow rate of the second reactant, an estimated value of the degree of the methanation process, and a required value of the degree of the methanation process. For example, the second reference value of the supply flow rate of the second reactant is calculated by using Equation (13) in combination with any of the equations in Equation (15).

[0119] According to one embodiment of the present invention, the first set of measured physical quantities also indicates the ratio between the first value of the amount of substance of dihydrogen in the product gas in the first control iteration and the first value of the amount of substance of methane in the product gas in the first control iteration.

[0120] In particular, each element of the first set of measured quantities is measured at a point in the first time interval, which is the measured value of the physical quantity of the product gas at the first iteration, i.e., the aforementioned point in time. Below, it can be shown that the quantities related to the first and second controlled iterations depend on times t1 and t2, respectively. Times t1 and t2 are included in the first and second time intervals, respectively.

[0121] In particular, the first set of measurements includes physical quantities that enable the estimation of a second ratio. For example, the first set of measurements includes a first measurement of the first ratio. For example, the first set of measurements includes a first measurement of the amount of substance of dihydrogen in the product gas in the first controlled iteration.

number

number

number

number

number

number

[0122] For example, the first estimate of the supply flow rate ratio can be given by:

number

[0123] In particular, the above formula is used when the amount of methane in the supply gas is small or zero. The first estimate of the supply flow rate ratio is x mea to s mea By substituting and using equation (22), the amounts of dihydrogen, methane, and carbon oxides in the product gas can be expressed in terms of these amounts.

[0124] Alternatively, or in conjunction with the above, the first information is generated by using a second set of measured physical quantities of the feed gas. The second set of measured physical quantities of the feed gas represents the ratio between a first value of the amount of methane in the feed gas in the first controlled iteration and a first value of the amount of carbon oxides in the feed gas in the first controlled iteration.

[0125] In particular, each element of the second set of measured quantities is measured at a point in the first time interval, which is the measured value of the physical quantity of the supply gas at the first iteration, i.e., the aforementioned point in time. For example, the second set of measured quantities consists of, for example, physical quantities that enable the estimation of the ratio (hereinafter also called the "third ratio") between a first value of the amount of methane in the supply gas and a first value of the amount of carbon oxide in the product gas at the first control iteration. For example, the first set of measured quantities consists of, for example, the first measured value of the third ratio.

[0126] For example, the first set of measurements is, for example, the first measured value of the amount of methane in the feed gas in the first controlled iteration.

number

number

number

number

number

number

[0127] The first estimate of the supply flow rate ratio can be given by:

number

[0128] The first estimate of the supply flow rate ratio is x mea to s mea By substituting and using equation (23), the amounts of dihydrogen, methane, and carbon oxides in the product gas and feed gas can be expressed in terms of these amounts.

[0129] In one embodiment of the present invention, the estimate of the degree of the methane process is expressed with respect to at least a second set of measured physical quantities of the supply gas. For example, the estimate of the degree of the methane process may be given by:

number

[0130] One embodiment of the present invention further includes the step of initiating the measurement of at least one measured physical quantity from a first set of measured physical quantities, for example, each measured quantity.

[0131] The step of initiating the measurement of a measured physical quantity from a first set of measured physical quantities may include instructing a computing device in the reactor and / or power plant to measure the quantity. In particular, the computing device controls a gas analyzer in the reactor, which is configured to analyze the composition of the product gas. In particular, this step may be performed by instructing the gas analyzer to measure a measured physical quantity from a first set of measured physical quantities.

[0132] Further embodiments of the present invention include the step of initiating the measurement of at least one measured physical quantity from a second set of measured physical quantities, for example, each measured quantity.

[0133] The step of initiating the measurement of a measured physical quantity from a second set of measured physical quantities may include instructing a computing device in the reactor and / or power plant to measure the quantities. In particular, the computing device controls a gas analyzer in the reactor, which is configured to analyze the composition of the feed gas. In particular, this step may be performed by instructing the gas analyzer to measure a measured physical quantity from a first set of measured physical quantities.

[0134] The step of initiating the measurement of the measured physical quantities (e.g., the measured physical quantities from a first set or a second set) may be performed by measuring the quantities. The computing device instructed to measure the measured physical quantities (e.g., the measured physical quantities from a first set or a second set) and the computing device performing the method according to the present invention may be located in different locations.

[0135] According to one embodiment of the present invention, calculating a first setpoint for the supply flow rate of a first reactant includes generating first information by using a first set of measured physical quantities. In particular, generating the first information includes calculating a first difference estimate by using a first set of measured physical quantities, for example via equation (1). For example, calculating a first difference estimate includes calculating a first estimate for the supply flow rate ratio by using a first set of measured physical quantities. The first estimate for the supply flow rate ratio can be calculated by using any of the equations in equations (2), (3), (22), and / or (23).

[0136] According to one embodiment of the present invention, calculating a first setpoint for the supply flow rate of the first reactant includes calculating a first setpoint for the supply flow rate ratio. Calculating the first setpoint for the supply flow rate ratio can be done by using a first estimate for the supply flow rate ratio, a first required value for the supply flow rate ratio, and a second required value for the supply flow rate ratio. For example, the calculation of the first setpoint for the supply flow rate ratio is performed by using equation (6) in combination with any of the equations in equation (8).

[0137] In particular, the first set value of the feed rate of the first reactant is calculated by using the first set value of the feed rate ratio and the first measured value of the feed rate of the second reactant. For example, if the first reactant is dihydrogen, the first set value of the feed rate of the first reactant can be calculated using equation (4). If the first reactant is a carbon oxide, such as carbon monoxide or carbon dioxide, the first set value of the feed rate of the first reactant can be calculated using the following equation (5).

[0138] Calculating a first set value for the supply flow rate of the first reactant may include calculating a second required value for the supply flow ratio by using a first required value for the supply flow ratio. For example, the calculation of the second required value for the supply flow ratio is performed by using equation (17) in combination with any of the equations in equations (19), (20), and (21).

[0139] A second aspect of the present invention relates to a method for iteratively controlling the dosing rate of an additive compound in a methanation process within a reactor. According to this aspect, the methanation process is carried out in a first culture medium within the reactor, and a product gas is produced by using a feed gas. In particular, the first culture medium, which contains water and the additive compound, and the feed gas, contain dihydrogen and carbon oxides. The method according to the second aspect of the present invention includes at least the following steps: - A step of starting the calculation of a first set value for the administration rate of the additive compound, wherein the calculation of the first set value for the administration rate of the additive compound is performed using the concentration value n ad and by using a set value for the supply flow rate of carbon oxide, the first set value for the dosing rate of the additive compound becomes appropriate to compensate for the drainage of water from the first medium, step and - A step of starting to modify the dosing rate of the additive compound according to a first set value of the supply flow rate of the additive compound.

[0140] The first setpoint for the dosing rate of the additive compound is proportional to the baseline concentration of the additive in the reactor and the fourth setpoint for the carbon oxide supply flow rate. The alkalinity-adjusting compound includes, and may consist of, ammonia and / or sodium hydroxide.

[0141] In particular, the set value for the carbon oxide supply flow rate is the set value for the carbon oxide supply flow rate in the first control iteration. The first set value for the additive compound administration rate is, in particular, the set value for the additive compound administration rate in the second control iteration.

number

[0142] In particular, in this embodiment, the chemical dosing of the additive compound allows the concentration of this compound in the first culture medium to be kept substantially constant. The chemical dosing is controlled by using a setpoint for the carbon oxide supply flow rate in the first control iteration, which is proportional to the water discharge in the first control iteration. Thus, the culture medium has better responsiveness to changes in conditions, and the process performance is more robust to the above changes. According to the present invention, the additive compound is dosed according to the expected washout of the compound, thereby reducing the delay in the effect of the dosing when compensating for the washout. Furthermore, if the estimated degree of the process is less than the required degree, dosing based on the expected washout of the compound may result in a transient increase in the concentration of the additive compound supporting the reaction. This transient increase leads to an increase in the degree of the process, thereby reducing the gap between the actual degree of the process and the required degree.

[0143] In particular, the first set value for the administration rate of the additive compound is given by the following:

number

[0144] In particular, the coefficient κ is the ratio of water to methane produced in the methanation reaction, expressed as kg-H2O / mol-carbon oxide. Specifically, in the case of methanation of carbon dioxide, the coefficient κ is equal to 0.036 kg-H2O / mol-CO2. In the case of methanation of carbon monoxide, the coefficient k is equal to 0.018 kg-H2O / mol-CO.

[0145] Furthermore, the first set value for the administration rate of the additive compound can be given by:

number

[0146] The coefficient μ is a correction factor introduced specifically to account for the amount of water evaporating and therefore not diluting the additive compound. The actual value of the coefficient can be calculated by using conventional methods, by taking into account the water saturation in the reactor headspace. For example, in the case of biomethanol at a temperature of about 60°C and a pressure of about 10 bar, the coefficient μ may be in the range of 0.9865 to 0.9885, particularly 0.9870 to 0.9880, and more specifically may be equal to 0.9875.

[0147] For example, the first set value for the supply flow rate of the additive compound is calculated by using at least equation (25) or equation (26).

[0148] A third aspect of the present invention relates to a method for iteratively controlling the dosing rate of an alkalinity-adjusting compound additive in a methanation process within a reactor. According to this aspect, the methanation process is carried out in a second culture medium within the reactor, and a product gas is produced by using a feed gas. In particular, the first culture medium, which contains water and an alkalinity-adjusting compound, and the feed gas, contain dihydrogen and carbon oxides. The method according to the third aspect of the present invention includes at least the following steps: - A step of starting the calculation of a first set value for the dosing rate of the alkalinity-adjusting compound, the calculation of the first set value for the dosing rate of the alkalinity-adjusting compound is performed by using a first required value for the supply flow rate of carbon oxide, and as a result the first set value for the dosing rate of the alkalinity-adjusting compound is appropriate to compensate for the acidification of the second medium, and - A step of starting to modify the supply flow rate of the alkalinity-modifying compound additive according to a first set value for the administration rate of the alkalinity-modifying compound.

[0149] The first set value for the dosing rate of the alkalinity-adjusting compound is proportional to the first required value for the carbon oxide supply flow rate.

[0150] The first required value for the carbon oxide supply flow rate is, in particular, the required value for the carbon oxide supply flow rate in the second control iteration.

number

number

[0151] The alkalinity-adjusting compound may be a strong base and / or a weak base. In particular, the alkalinity-adjusting compound may include ammonia and / or phosphates, and may be composed of these, for example.

[0152] The first set value for the administration rate of the alkalinity-adjusting compound can be given by:

number

[0153] In particular, the coefficient η is a factor that increases the steady-state concentration of the alkalinity-regulating compound with the flow rate of carbon oxides, thereby reducing the change in pH of the second medium. For example, in the case of methane production of carbon dioxide, and the alkalinity-regulating compound is NH3, the coefficient η is equal to 0.008 mol-NH3 / mol-CO2. For example, the calculation of the first setpoint for the administration rate of the alkalinity-regulating compound is performed by using at least equation (27).

[0154] In the methanation process, alkalinity-modulating compounds can be added to a second culture medium to compensate for acidification caused by the dissolution of acidic reactive gases such as carbon dioxide in this medium. Controlling the supply flow rate of the alkalinity-modulating compound is achieved by using a first required supply flow rate of carbon oxide, which allows for a relatively rapid increase in the concentration of the alkalinity-modulating compound, thereby rapidly counteracting the acidification of the second culture medium.

[0155] According to the present invention, the step of initiating the modification of the compound administration rate according to a set value of the administration rate may include transmitting the set value to a computing device in the reactor and / or power plant. In particular, the computing device controls a valve in the reactor or power plant, and the valve adjusts the compound administration rate in the reactor. In particular, this step may be carried out by modifying the compound administration rate according to a set value of the compound administration rate.

[0156] The step of initiating a modification of the compound administration rate according to a set value for the administration rate may include instructing a computing device to modify the rate. For example, the computing device instructed to modify the compound administration rate and the computing device performing the method according to the present invention may be located in different locations.

[0157] For example, modifying the compound administration rate according to a first set value may include controlling a valve in a reactor or power plant, the valve adjusting the compound administration rate to the reactor. For example, the valve may be controlled to adjust the compound administration rate according to a set value of the compound.

[0158] According to the present invention, the calculation of a quantity value (e.g., a set value for the feed flow rate of the reactants, an estimate of the degree of the methane process, a required set value or estimate for the feed flow rate ratio, and / or a set value for the compound dosing rate) can be initiated by calculating the quantity value. Alternatively, or in conjunction with the above, the calculation of the quantity value may be initiated by instructing a computing device in the reactor and / or power plant to calculate the quantity value. For example, the calculation of the quantity value can be initiated by providing the computing device with at least a measured physical quantity from a first set of measured physical quantities and / or a measured physical quantity from a first set of measured physical quantities. Alternatively, or in conjunction with the above, the calculation of the above quantity values ​​may be initiated by providing the computing device with a first measured value of the feed rate of the second reactant, a first reference value of the feed rate of the second reactant, a first required value of the feed rate ratio, a required value of the degree of the methanation process, a second required value of the feed rate ratio, a value of the concentration of the additive compound in the first culture medium, a reference value of the molar mass of water in the first culture medium, and / or a first required value of the feed rate of carbon oxide. For example, the computing device instructed to calculate the quantity values ​​and the computing device performing the method according to the present invention may be located in different locations.

[0159] It should be noted that any of the various features of each of the above embodiments of the present invention can be included in or combined with each of those embodiments as appropriate and desired.

[0160] In particular, a second aspect of the present invention may be combined with a first aspect of the present invention. For example, a method of a second aspect of the present invention may include one or more steps of a method according to a first aspect of the present invention. In this case, if the second reactant is a carbon oxide, the set value of the carbon oxide supply flow rate in the second aspect of the present invention may be a first set value of the supply flow rate of the second reactant. Furthermore, if the first reactant is a carbon oxide, the set value of the carbon oxide supply flow rate in the second aspect of the present invention may be a set value of the supply flow rate of the first reactant in the first control iteration. For example, a method according to a second aspect of the present invention may include a step of initiating the calculation of the set value of the first reactant.

[0161] A third aspect of the present invention may be combined with a second aspect of the present invention. In particular, the method of the third aspect of the present invention may include one or more steps of the method according to the second aspect of the present invention, and / or the method of the second aspect of the present invention may include one or more steps of the method according to the third aspect of the present invention. In particular, the second medium may be equal to the first medium, that is, the second medium may contain an additive compound.

[0162] A third aspect of the present invention may also be combined with a first aspect of the present invention. In particular, the method of the third aspect of the present invention may include one or more steps of the method according to the first aspect of the present invention. In this case, if the second reactant is a carbon oxide, the first required flow rate of the carbon oxide according to the third aspect of the present invention may be the first required flow rate of the second reactant according to the first aspect of the present invention.

[0163] The present invention also relates to a data processing system comprising processing means configured to carry out the method according to the first aspect of the present invention, the method according to the second aspect of the present invention, and / or the method according to the third aspect of the present invention. Furthermore, the present invention also relates to a reactor assembly for carrying out a methanation process including the data processing system of the present invention. In particular, the reactor assembly may comprise measuring means for measuring at least one of a first set of measured physical quantities.

[0164] The present invention relates to a computer program product that, when the program is executed by a data processing system, includes instructions that cause the system to perform a method according to a first aspect of the present invention, a method according to a second aspect of the present invention, and / or a method according to a third aspect of the present invention. In particular, the computer program product includes instructions that, when the program is executed by a reactor assembly of the present invention, cause the assembly to perform at least one of the methods of the present invention.

[0165] Furthermore, the present invention relates to a computer-readable storage medium that, when executed by a data processing system, includes instructions causing the system to perform a method according to a first aspect of the present invention, a method according to a second aspect of the present invention, and / or a method according to a third aspect of the present invention. In particular, the computer-readable storage medium, when executed by a reactor assembly of the present invention, includes instructions causing the assembly to perform at least one of the methods of the present invention.

[0166] Exemplary embodiments of the present invention are described below with reference to the accompanying drawings. The drawings and corresponding detailed descriptions are merely for the purpose of providing a better understanding of the present invention and do not constitute any limitation of the scope of the invention as defined in the claims. [Brief explanation of the drawing]

[0167] [Figure 1] This is a schematic diagram of an embodiment of a reactor assembly according to the present invention. [Figure 2] This is a flowchart illustrating the operation of the first embodiment of the method according to the first aspect of the present invention. [Figure 3] This is a flowchart illustrating the operation of a second embodiment of the method according to the first aspect of the present invention. [Figure 4] This is a flowchart illustrating the operation of the first embodiment of the method according to a second aspect of the present invention. [Figure 5a] The time dependence of the required and measured supply flow ratios for the first simulation of carbon dioxide methane production is shown. [Figure 5b] The time dependence of the amount of methane in the product gas to the product gas in the first simulation is shown. [Figure 5c] The time dependence of the amount of dihydrogen in the product gas to the product gas in the first simulation is shown. [Figure 6a] This shows the time dependence of the carbon dioxide supply flow rate setpoint in the first simulation of carbon dioxide methane conversion. [Figure 6b] The second simulation shows the time dependence of the amounts of methane, dihydrogen, and carbon dioxide in the product gas on the product gas. [Figure 6c] The time dependence of the required and measured supply flow ratios for the second simulation of carbon dioxide methane production is shown. [Modes for carrying out the invention]

[0168] Figure 1 is a schematic diagram of one embodiment of the reactor assembly 100 according to the present invention.

[0169] The reactor assembly 100 comprises a carbon oxide supply unit 114, a dihydrogen supply unit 124, a gas supply unit 164, a reactor 160, and a product gas conduit 144. The carbon oxide supply unit 114 fluidly connects the gas supply unit 164 to the carbon oxide source 110. The carbon oxide source 110 may be a tank for storing the first supply gas, or a biogas reactor that generates the supply gas. The first supply gas contains carbon oxides and may further contain methane.

[0170] The dihydrogen supply unit 124 fluidly connects the gas supply 164 to the dihydrogen source 120. The dihydrogen source 120 may be a tank for storing the second supply gas, or a reactor that generates the second supply gas dihydrogen from H2O by a suitable electrolytic reaction, for example. In particular, the second supply gas consists of dihydrogen and one or more impurities.

[0171] The gas supply 164 fluidly connects the carbon oxide source 110 and the dihydrogen source 120 to the reactor 160, which is fluidly connected to the product gas conduit 144. The reactor 160 is configured to contain an aqueous culture medium containing suitable methane-producing microorganisms, such as archaea, for converting the supply gas into product gas. The product gas conduit 144 fluidly connects the reactor 160 to a tank 140 for storing the product gas and / or to a grid (not shown) for distributing the product gas.

[0172] During operation, a first supply gas is transferred from a carbon oxide source 110 to the reactor 160 via a carbon oxide supply unit 114 and a gas supply 164. A second supply gas is transferred from a dihydrogen source 120 to the reactor 160 via a dihydrogen supply unit 124 and a gas supply 164. During operation, the reactor 160 contains an aqueous culture medium, and carbon oxides and dihydrogen are dissolved in the medium. Methane-producing microorganisms carry out the methanation process using carbon oxides and dihydrogen. The product gas produced in the reactor is transferred to a tank 140 and / or grid using a product gas conduit 144.

[0173] The reactor assembly 100 includes a first valve 112 and a second valve 122. The first valve 112 is connected to a carbon oxide supply unit 114 and is configured to regulate the supply flow rate of a second supply gas flowing through the carbon oxide supply unit 114 during operation. The supply flow rate of the first supply gas is regulated according to a set value for the supply flow rate of the first supply gas, for example, so that the nominal value of the supply flow rate of the first supply gas flowing through the carbon oxide supply unit 114 is substantially equal to the set value for the supply flow rate of the first supply gas. The second valve 122 is connected to a dihydrogen supply unit 124 and is configured to regulate the supply flow rate of dihydrogen flowing through the dihydrogen supply unit 124 during operation. The supply flow rate of the second supply gas is regulated according to a set value for the supply flow rate of the second supply gas, for example, so that the nominal value of the supply flow rate of the second supply gas flowing through the dihydrogen supply unit 124 is substantially equal to the set value for the supply flow rate of the second supply gas. The first valve 112 and / or the second valve 122 may be intelligent devices having their own CPU and / or memory.

[0174] The reactor assembly 100 includes a first flow meter 113 connected to a carbon oxide feed unit 114. The first flow meter 113 is configured to measure the feed rate of a first feed gas flowing through the carbon oxide feed unit 114 during operation, for example, a volumetric feed rate. The reactor assembly 100 may further include a second flow meter 123 which can be connected to a dihydrogen feed unit 124. If present, the second flow meter 123 may be configured to measure the feed rate of a second feed gas flowing through the dihydrogen feed unit 124 during operation, for example, a volumetric feed rate. For example, the first flow meter 113 and / or the second flow meter 123 are vortex-generating flow meters and / or intelligent devices having their own CPU and memory.

[0175] The reactor assembly includes a first gas analyzer 111 connected to a carbon oxide supply unit 114. The first gas analyzer 111 is configured to analyze the composition of the first supply gas flowing through the carbon oxide supply unit 114 during operation. In particular, the first gas analyzer 111 measures the amount of carbon oxides in the first supply gas relative to the first supply gas.

number

number

number

number

number

[0176] The reactor assembly comprises a data processing system (DPS) 150 which may include a computing device or a cluster thereof. The data processing system 150 has processing elements 158 and storage means 159 that communicate with each other. The processing elements 158 may consist of a CPU and / or a GPU, or may include a CPU and / or a GPU, and comprise several modules configured to perform steps of the method of the present invention.

[0177] The storage means 159 may include volatile primary memory (e.g., RAM, DRAM, SRAM, CPU cache memory, etc.) and / or non-volatile primary memory (e.g., ROM, PROM, EPROM, etc.). The storage means 159 may further include secondary memory. The secondary memory may store a computer program product that, when executed by the DPS 150, causes the DPS 150 to execute the method according to the present invention.

[0178] The DPS includes an input / output (IO) interface (not shown) that enables the DPS150 to communicate with an input / output device, for example, a device configured to provide the DPS150 with a requested feed rate ratio and / or a requested feed rate for a second reactant.

[0179] The processing element 158 ​​includes a first module (not shown) configured to instruct a first valve 112 to adjust the supply flow rate of a first supply gas according to a set value of the supply flow rate. Commands from the DPS 150 are transmitted to the first valve 112 via an electrical, optical, and / or wireless connection 151 between the DPS 150 and the first valve 112. The processing element 158 ​​also includes a second module (not shown) configured to instruct a second valve 122 to adjust the supply flow rate of a second supply gas according to its set value. Commands from the DPS 150 are transmitted to the second valve 122 via an electrical, optical, and / or wireless connection 152 between the DPS 150 and the second valve 122.

[0180] The processing element 158 ​​includes a third module (not shown) configured to instruct a first gas analyzer 111 to measure the concentrations of carbon oxides and methane in a first feed gas. Commands from the DPS 150 are transmitted to the first gas analyzer 111 via an electrical, optical, and / or wireless connection 153. In response to the command from the DPS 150, the first gas analyzer 111 performs the measurement and transmits the measurement results to the DPS 150 via the connection 153. The third module is configured to access the measurement results transmitted by the first gas analyzer 111. The processing element 158 ​​also includes a fourth module (not shown) configured to instruct a second gas analyzer 141 to measure the concentrations of carbon dioxide, dihydrogen, and methane in the product gas. Commands from the DPS 150 are transmitted to the second gas analyzer 141 via an electrical, optical, and / or wireless connection 155. In response to a command from DPS150, the second gas analyzer 141 performs a measurement and transmits the measurement result to DPS150 via connection 155. The fourth module is further configured to access the measurement result transmitted by the second gas analyzer 141.

[0181] The processing element 158 ​​includes a fifth module (not shown) configured to instruct a first flow meter 113 to measure the supply flow rate of a first supply gas. Commands from DPS 150 are transmitted to the first flow meter 113 via electrical, optical, and / or wireless connections 155. In response to the command from DPS 150, the first flow meter 113 performs the measurement and transmits the measurement result to DPS 150 via connections 155. The fifth module is configured to access the measurement result transmitted by the first flow meter 113. The processing element 158 ​​also includes a sixth module (not shown) configured to instruct a second flow meter 123 to measure the supply flow rate of a second supply gas. Commands from DPS 150 are transmitted to the second flow meter 113 via electrical, optical, and / or wireless connections 156. In response to a command from DPS150, the second flowmeter 123 performs a measurement and transmits the measurement result to DPS150 via connection 156. The sixth module is configured to access the measurement result transmitted by the second flowmeter 123.

[0182] The reactor assembly may include an additive compound supply unit 134 and a third valve 132. The additive compound supply unit 134 fluidly connects the reactor 160 to a tank 130, and the tank 130 is configured to store the additive compound. The additive compound may be in liquid form and may contain water and ammonia, with the ammonia dissolved in water. During operation, the additive compound is transferred from the tank 130 to the reactor 160 via the additive compound supply unit 134, thereby mixing with the aqueous culture medium to maintain favorable conditions for methane formation in the reactor.

[0183] The reactor assembly may include a third valve 132 connected to an additive compound supply unit 134 and configured to regulate the dosing rate of the additive compound flowing through the additive compound supply unit 134 during operation. The dosing rate regulation is performed according to a set value of the dosing rate, so that the value of the dosing rate of the additive compound flowing through the additive compound supply unit 134 is substantially equal to the set value of the dosing rate. The third valve 132 may be an intelligent device having its own CPU and / or memory. The processing element 158 ​​may include a seventh module (not shown) configured to instruct the third valve 132 to regulate the dosing rate of the additive compound according to the set value of the dosing rate. Instructions from the DPS 150 are transmitted to the third valve 132 via electrical, optical, and / or wireless connections 157.

[0184] Figure 2 is a flowchart 200 of the operation of a first embodiment of a first aspect of the present invention. In this embodiment, the first reactant is dihydrogen, and for example, carbon oxides are the main reactants. In particular, the above embodiment can be carried out by the reactor assembly 100 described above and schematically shown in Figure 1. The first embodiment of a first aspect of the present invention includes a plurality of controlled iterations.

[0185] In step 205, DPS150 sets the required value b of the supply flow rate ratio in the first control iteration. req (t1) and the required carbon oxide supply flow rate in the first control iteration

number

number

number

[0186] In step 210, the supply flow rate of the first supply gas is set to the required value

number

number

number

number

[0187] A general control iteration among the multiple control iterations of this embodiment is described with respect to a counter m, which is initialized to a value of zero in step 255. As described above, the m-th control iteration is associated with each m-th time interval, which is time t m This includes the m-th time interval, which does not overlap with the (m-1) time interval, but follows it in time t. m This includes the difference (t) for each m. m -t m-1 ) is equal to 15 seconds. Below, the quantity related to the mth control iteration is time t m It can be shown that it depends on t. m The measured values ​​shown to depend on time t are, in particular, the values ​​measured in the mth control iteration, but not necessarily at time t. m It does not need to be in that location.

[0188] In step 215 of the mth control iteration, the measured supply flow rate of the first supply gas

number

number

number

[0189] In step 220 of the m-th control iteration, the measured amount of carbon oxide in the product gas relative to the product gas.

number

number

number

number

number

[0190] In step 225 of the m-th control iteration, the measured amount of carbon oxides in the first supply gas relative to the first supply gas is

number

number

number

number

[0191] In step 230 of the mth control iteration, DPS150 sets the required value b of the supply flow rate ratio in the (m+1) control iteration. req (t m+1 ) and the required carbon oxide supply flow rate in the (m+1) control iteration

number

number

number

number

[0192] In step 235 of the m-th control iteration, DPS150 is set to the dihydrogen supply flow rate set in the (m+1) control iteration.

number

number

[0193] Step 235 estimates the time derivative D of the first function in the mth controlled iteration according to the following equation. b,m and the estimated time integral I of the first function in the mth controlled iteration. b,m This includes calculating:

number

number

[0194] The DPS150 has a set value b for the supply flow rate ratio in the (m+1) control iteration. sp (t m+1 ) calculate.

number

number

number

[0195] In step 240, the supply flow rate of the second supply gas is set to the set value

number

number

number

number

number

number

[0196] In step 250 of the mth iteration, the DPS150 checks whether the iterative control of the methanation process should be terminated or continued. For example, the iterative control of the methanation process may be terminated when the reactor assembly is shut down, for example, for maintenance. If the iterative control of the methanation process should be continued, the DPS150 increments the value of the counter by 1 (see step 260) and performs the (m+1) control iteration.

[0197] Further embodiments of the method according to the first aspect of the present invention may include steps 205-260 described above. In particular, these embodiments differ from the first embodiment of the first aspect of the present invention in the order in which steps 215-230 are performed. In particular, in further embodiments, steps 220, 225, and / or 230 may be performed in any order prior to step 215. Alternatively, or in conjunction with the above, steps 215, 220, and / or 225 may be performed in any order after step 230 and prior to step 235. In some embodiments, step 245 may be performed before steps 240 and / or 235 and after step 230.

[0198] Figure 3 is a flowchart 200 of the operation of a second embodiment of the method of the present invention. In this embodiment, the first reactant is dihydrogen, and for example, a carbon oxide is the main reactant. In particular, the above embodiment can be carried out by the reactor assembly 100 described above and schematically shown in Figure 1.

[0199] The second embodiment includes a plurality of control iterations. A general control iteration among the plurality of control iterations of this embodiment is described with respect to a counter m, which is initialized to the value zero in step 255. As described above, the m-th control iteration is associated with each m-th time interval, which is time t m This includes the m-th time interval, which does not overlap with the (m-1) time interval, but follows it in time t. m This includes the difference (t) for each m. m -t m-1 ) is equal to 15 seconds. Below, the quantity related to the mth control iteration is time t m It can be shown that it depends on time t. m The measured values ​​shown to depend on time t are, in particular, the values ​​measured in the mth control iteration, but not necessarily at time t. m It does not need to be in that location.

[0200] In step 205, DPS150 sets the required value b of the supply flow rate ratio in the first control iteration. req(t1) Required value of carbon oxide supply flow rate in the first control iteration

number

number

number

number

[0201] Steps 210, 215, 220, and 225 of the second embodiment are identical to steps 210, 215, 220, and 225 of the first embodiment, respectively, as described above and schematically shown in Figure 2.

[0202] In step 310 of the mth control iteration, DPS150 is set to the required value y of the degree of the methane process in the (m+1) control iteration. req (t m+1 ) and the required carbon oxide supply flow rate in the (m+1) control iteration

number

number

number

number

[0203] In step 320 of the m-th control iteration, DPS150 is set to the set value of the carbon oxide supply flow rate in the (m+1) control iteration.

number

[0204] In step 320, DPS150 is the reference value for the carbon oxide supply flow rate in the (m+1) control iteration, as follows:

number

number

number

number

[0205] Set value of carbon oxide supply flow rate in the (m+1) control iteration

number

number

[0206] In step 330 of the m-th control iteration, DPS150 is set to the set value of the dihydrogen supply flow rate in the (m+1) control iteration.

number

[0207] DPS150 is t1 tm By substituting and using equation (24), we can estimate the degree of the methane process in the m-th controlled iteration y est (t m ) is calculated. DPS150 is calculated by substituting b with y and using equation (28) to obtain the value of the second function f in the mth iteration. y,m We also calculate the value y. req (t m ) is the required value of the supply flow rate ratio in the mth iteration, which is accessed by DPS150 in step 310 of the (m-1)th control iteration. Step 330 is accessed by the function g defined in equation (18). yy and the function f of equation (14) y Regarding this, the value of the third function g in the mth iteration y,m This includes calculating:

number

[0208] Step 330 is the estimate of the time derivative of the third function in the mth controlled iteration.

number

number

number

[0209] In step 330, DPS is the required value b of the supply flow rate ratio in the mth control iteration. req (t m+1 Regarding ), the required value b of the supply flow rate ratio in the (m+1) iteration.req (t m+1 ) calculate:

number

[0210] For example, c 7 = -500, c 8 = -50 min, and c 9 = -500 min -1 Step 330 is performed by using equation (30) to obtain the required value b of equation (33). req (t m+1 Regarding the set value b of the supply flow rate ratio in the (m+1) control iteration, sp (t m+1 This includes calculating the set value b. sp (t m+1 ) is t1 to t m to, and t2 to t m+1 Substituting this and using equation (4), the set value of the dihydrogen supply flow rate in the (m+1) control iteration

number

number

[0211] Step 240 is identical to step 240 of the first embodiment of the first aspect of the present invention, as described above and schematically shown in Figure 2. In step 245, the supply flow rate of the first supply gas is set to the carbon oxide set value

number

number

number

number

[0212] Further embodiments of the method according to the first aspect of the present invention may include steps 205-225, 310-330, and 240-260 described above. In particular, these embodiments differ from the second embodiment of the first aspect of the present invention in the order in which steps 215-225 and 310 are performed. In particular, in further embodiments, steps 220, 225, and / or 310 may be performed in any order before step 215. Alternatively, or in conjunction with the above, steps 215, 220, and / or 225 may be performed in any order after step 310 and before step 320. In some embodiments, step 245 may be performed before steps 240 and / or 330 and after step 320.

[0213] Figure 4 is a flowchart 400 of the operation of the first embodiment of a second aspect of the present invention. In particular, the above embodiment can be carried out by the reactor assembly described above and schematically shown in Figure 2. The first embodiment of a third aspect of the present invention includes a plurality of control iterations. A general control iteration of the plurality of control iterations of this embodiment is described with respect to a counter m, which is initialized to a value of zero in step 405. As described above, the m-th control iteration is associated with each m-th time interval, which is time t mThis includes the m-th time interval, which does not overlap with the (m-1) time interval, but follows it in time t. m This includes the difference (t) for each m. m -t m-1 ) is equal to 15 seconds. Below, the quantity related to the mth control iteration is time t m It can be shown that it depends on time t. m The measured values ​​shown to depend on time t are, in particular, the values ​​measured in the mth control iteration, but not necessarily at time t. m It does not need to be in that location.

[0214] In step 415 of the mth control iteration, DPS150 is set to the set value of the carbon oxide supply flow rate in the mth control iteration.

number

number

number

number

[0215] In step 420 of the m-th control iteration, DPS150 is the set value for the dosing rate of the additive compound in the (m+1) control iteration.

number

number

number

number

[0216] In step 430 of the mth iteration, the DPS150 checks whether the iterative control of the additive compound dosing should be terminated or continued. For example, the iterative control of the additive compound dosing may be terminated, for example, by shutting down the reactor assembly for maintenance. If the iterative control of the additive compound dosing should be continued, the DPS150 increments the value of the counter by 1 (see step 260) and performs the (m+1) control iteration.

[0217] Figure 5a shows the time dependence of the required feed flow rate ratio (dashed line) and the measured feed flow rate ratio (solid line) in a first simulation of methane production of carbon dioxide in a reactor assembly according to the present invention, e.g., the one described above and schematically shown in Figure 1. In the first simulation, the measurements from the first gas analyzer 111, the second analyzer 141, the first flow meter 113, and the second flow meter 123 are affected by randomly generated noise. A negative bias of -0.5% on the measurement from the first flow meter 113 simulates undetectable fluctuations in the composition of the first feed gas. In the first simulation, the required feed flow rate of carbon dioxide is constant.

number

[0218] In the first period 501, the methane process is iteratively controlled by using the first embodiment of the first aspect of the present invention, as described above and schematically shown in Figure 2. In the second period 502, the method according to the first aspect of the present invention is not performed.

[0219] During the second period 502, the supply flow rates of the first and second gas supplies are periodically repeated at times τ1, τ2, ...τ M It is set periodically. Typical time τ s In this context, DPS150 is the required value for the carbon dioxide supply flow rate.

number

number

number

number

number

number

number

[0220] Time dependence of measured supply flow rate ratio b mea This is obtained by periodically estimating the ratio of the supply flow rate of dihydrogen to the supply flow rate of carbon dioxide, the estimation of which is the supply flow rate of the first supply gas, the supply flow rate of the second supply gas, and the amount of methane in the first supply gas relative to the first supply gas.

number

[0221] In the first period 501, the iterative control of the first aspect of the present invention allows for bias compensation, and therefore the solid curve substantially overlaps with the dashed curve and oscillates around the dashed curve. In the second period, the bias is not compensated, and the measured supply flow ratio is systematically smaller than the required one.

[0222] Figures 5b and 5c show the measured amounts of methane in the product gas relative to the product gas in the second simulation, respectively.

number

number

[0223] In the first period 501, the time dependencies 510 and 520 shown in Figures 5b and 5c were measured in step 220 of each control iteration of the first embodiment of the first aspect of the present invention.

number

[0224] Figures 5b and 5c show that the method according to a second aspect of the present invention improves the degree of the methane process. In particular, as best shown in Figure 5b, b req If the values ​​are the same, during the first period 501

number

number

number

number

[0225] Figure 6a shows the set values ​​for the carbon dioxide supply flow rate in a second simulation of carbon dioxide methane production in a reactor assembly according to the present invention, for example, the one described above and schematically shown in Figure 1.

number

[0226] Figure 6a also shows the time dependence of the required carbon dioxide supply flow rate in the second simulation (dotted line).

number

number

number

number

[0227] Figure 6b shows the estimated amount of methane in the product gas relative to the product gas in the second simulation.

number

number

number

number

[0228] Figure 6c shows the required supply flow rate ratio b for the second simulation. req Time dependence (dashed line) and measured supply flow rate ratio b mea The time dependence (solid line) is shown. The time dependence of the measured supply flow rate ratio is obtained by periodically estimating the ratio between the supply flow rate of dihydrogen and the supply flow rate of carbon dioxide, the above estimation is based on the supply flow rate of the first supply gas, the supply flow rate of the second supply gas, and the amount of methane in the first supply gas relative to the first supply gas.

number

[0229] Initial value of the carbon oxide supply flow rate setting

number

number

number

number

number

number

[0230] In about 20 minutes,

number

number

number

number

number

number

number

number

number

[0231] In about 150 minutes,

number

number

number

number

number

[0232] In the fifth period, 605, over approximately 200 minutes,

number

number

number

number

number

number

number

number

number

[0233] In the sixth period 606, the set value

number

number

Claims

1. A computer implementation method for iteratively controlling the supply flow rate of a first reactant in a methanation process within a reactor, wherein the methanation process is carried out within the reactor and generates a product gas by using a feed gas, the feed gas comprising a first reactant and a second reactant, the first reactant being one of dihydrogen and carbon oxide, and the second reactant being the other of dihydrogen and carbon oxide. The aforementioned method, - A step of starting the calculation of a first set value for the supply flow rate of the first reactant, - A step of starting to modify the supply flow rate of the first reactant according to the first set value of the supply flow rate of the first reactant. Includes, The calculation of the first set value of the supply flow rate of the first reactant is performed by using first information, the first information indicating whether the estimated value of the first difference between the estimated value of the supply flow rate ratio in the first control iteration and the first required value of the supply flow rate ratio in the first control iteration is positive or negative. The supply flow rate ratio is the ratio between the supply flow rate of the first reactant and the supply flow rate of the second reactant, and the first information is generated by using a first set of measured physical quantities of the product gas. The first set of measured physical quantities represents the ratio between a first value of the amount of substance of the carbon oxide in the product gas in the first controlled iteration and a first value of the amount of substance of methane in the product gas in the first controlled iteration. method.

2. The calculation of the first set value of the supply flow rate of the first reactant is performed according to the first set value of the supply flow rate ratio. According to the first information, if the estimated value of the first difference is positive, the first set value of the supply flow rate ratio is lower than the second required value of the supply flow rate ratio. According to the first information, if the estimated value of the first difference is negative, the first set value of the supply flow rate ratio is greater than the second required value of the supply flow rate ratio. The second required value of the supply flow rate ratio is the required value of the supply flow rate ratio in the second control iteration, and the first control iteration precedes the second control iteration in time. The method according to claim 1.

3. The step of calculating the first set value of the supply flow rate of the first reactant includes the step of calculating the first value of the first function, The first function is an increasing function of the difference between the estimated supply flow rate ratio and the required supply flow rate ratio, and the first value of the first function is the value of the first function in the estimated value of the first difference. When the first reactant is dihydrogen, the first set value of the supply flow rate of the first reactant is a decreasing function of the first value of the first function; when the first reactant is a carbon oxide, the first set value of the supply flow rate of the first reactant is an increasing function of the first value of the first function. The method according to claim 1 or 2.

4. - A step of starting the calculation of a second set value for the supply flow rate of the second reactant, wherein the calculation of the second set value for the supply flow rate of the second reactant is performed by using at least a first set value for the supply flow rate of the second reactant and the ramping rate of the supply flow rate of the second reactant, - A step of starting the modification of the supply flow rate of the second reactant according to the second set value of the supply flow rate of the second reactant. It further includes, If the first set value of the supply flow rate of the second reactant is greater than the first required value of the supply flow rate of the second reactant, the second set value of the supply flow rate of the second reactant is less than the first set value of the supply flow rate of the second reactant. If the first set value of the supply flow rate of the second reactant is smaller than the first required value of the supply flow rate of the second reactant, the second set value of the supply flow rate of the second reactant is larger than the first set value of the supply flow rate of the second reactant. The method according to any one of claims 1 to 3.

5. The calculation of the first set value of the supply flow rate of the first reactant is performed by using second information, the second information indicating whether the estimated second difference between the estimated degree of the methanation process in the first control iteration and the required degree of the methanation process in the first control iteration is positive or negative. The method according to any one of claims 1 to 4.

6. - A step of starting the calculation of the third set value of the supply flow rate of the second reactant, wherein the calculation of the third set value of the supply flow rate of the second reactant is performed by using the first reference value of the supply flow rate of the second reactant in the first control iteration and the first value of the supply flow rate of the second reactant, - A step of starting the modification of the supply flow rate of the second reactant according to the third set value of the supply flow rate of the second reactant. It further includes, The third set value of the supply flow rate of the second reactant is equal to the minimum value between the second reference value of the supply flow rate of the second reactant and the first value of the supply flow rate of the second reactant in the second control iteration. According to the second information, if the estimated value of the second difference is positive, the second reference value of the supply flow rate of the second reactant is greater than the first reference value of the supply flow rate of the second reactant; according to the second information, if the estimated value of the second difference is negative, the second reference value of the supply flow rate of the second reactant is less than the first reference value of the supply flow rate of the second reactant. The method according to any one of claims 1 to 5.

7. The step of calculating the first set value of the supply flow rate of the first reactant includes the step of calculating the first value of the second function, The second function is an increasing function of the difference between the estimated degree of the methanation process and the required degree of the methanation process, and the first value of the second function is the value of the second function in the estimated value of the second difference. The second reference value of the supply flow rate of the second reactant is proportional to the first reference value of the supply flow rate of the second reactant and is an increasing function of the first value of the second function. The method according to any one of claims 1 to 6.

8. The step of calculating the first set value of the supply flow rate of the first reactant includes the step of calculating the first value of the third function, The third function is an increasing function of the difference between the estimated degree of the methanation process and the required degree of the methanation process, and the first value of the third function is the value of the third function in the estimated value of the second difference. When the first reactant is dihydrogen, the first set value of the supply flow rate of the first reactant is a decreasing function of the first value of the third function; when the first reactant is a carbon oxide, the first set value of the supply flow rate of the first reactant is an increasing function of the first value of the third function. The method according to any one of claims 5 to 7.

9. The step of calculating the first set value of the supply flow rate of the first reactant is: - A step of generating the first information by using the first set of measured physical quantities. The method according to any one of claims 1 to 8, including the method described in any one of claims 1 to 8.

10. The methanation process is carried out in a first culture medium in the reactor, the first culture medium comprising water and an additive compound, and the method is - A step of starting the calculation of a first set value for the administration rate of the additive compound, wherein the calculation of the first set value for the administration rate of the additive compound is performed using a value for the concentration of the additive compound in the first culture medium and a fourth set value for the supply flow rate of carbon oxide, so that the first set value for the administration rate of the additive compound is appropriate for compensating for the discharge of water from the first culture medium, - A step of starting the modification of the administration rate of the additive compound according to the first set value of the administration rate of the additive compound. It further includes, The first set value of the administration rate of the additive compound is proportional to the concentration of the additive compound in the reactor and the fourth set value of the supply flow rate of carbon oxide. The method according to any one of claims 1 to 9.

11. The methanation process is carried out in a second culture medium in the reactor, the second culture medium comprising water and an alkalinity adjusting compound, and the method is - A step of starting the calculation of a first set value for the administration rate of the alkalinity-adjusting compound, wherein the calculation of the first set value for the administration rate of the alkalinity-adjusting compound is performed by using a first required value for the supply flow rate of carbon oxide, so that the first set value for the administration rate of the alkalinity-adjusting compound is appropriate for compensating for the acidification of the second medium, - A step of starting the modification of the supply flow rate of the alkalinity-adjusting compound additive according to the first set value of the administration rate of the alkalinity-adjusting compound. It further includes, The first set value of the administration rate of the alkalinity-adjusting compound is proportional to the first required value of the supply flow rate of the carbon oxide. The method according to any one of claims 1 to 10.

12. A data processing system comprising processing means configured to perform the method described in any one of claims 1 to 11.

13. A reactor assembly for performing a methane process, comprising the data processing system described in claim 12.

14. The reactor assembly according to claim 13, further comprising a filtration element for separating a first reactant or a second reactant from a product gas, and a back-loop gas conduit fluidly connected to a product gas conduit via the gas filtration element and gas supply.

15. The reactor assembly according to claim 14, further comprising a three-way valve for connecting and controlling the gas flow generated from a dihydrogen source of the first or second reactant via a supply section, wherein the gas flow is generated from the product gas via the filtration element and the back-loop gas conduit and leads to the gas supply.

16. A computer program product wherein, when the program is executed by a data processing system, the program includes an instruction that causes the system to perform the method according to any one of claims 1 to 11.

17. A computer-readable storage medium, which, when executed by a data processing system, includes an instruction causing the system to perform the method according to any one of claims 1 to 11.

Images