Method for controlling steam pipe network and steam pipe network

Abstract

The invention relates to a method for controlling a vapour network, in which the vapour network comprises a plurality of sub-networks (1a-c), in which each sub-network (1a-c) is connected to a respective external vapour generating source (2a-c), which supplies vapour to the respective sub-network (1a-c) at a respective internal vapour pressure, in which, for each sub-network (1a-c), the vapour generating source (2a-c) supplies vapour to the respective sub-network (1a-c) at a respective internal vapour pressure. The invention relates to a steam pipe network comprising a plurality of sub-pipe networks (1a-c), said sub-pipe networks (1a-c) having respective internal steam pressures that differ, said steam pipe network further comprising a plurality of steam consuming devices (3a-f), each steam consuming device (3a-f) being supplied with steam by a respective sub-pipe network (1a-c), said steam pipe network further comprising at least one inter-pipe valve (5a, 5b) for interconnecting a respective pair of said plurality of sub-pipe networks (1a-c), the method comprises: a) measuring steam consumption data (10) for each sub-pipe network (1a-c); b) predicting a future steam consumption rate (9) for each sub-network (1a-c) based on the measured steam consumption data (10) for each sub-network (1a-c); and c) controlling the at least one inter-network valve (5a-b) based on the predicted future steam consumption rate (9) for providing steam from a sub-network (1a-c) having a higher internal steam pressure to a sub-network (1a-c) having a lower internal steam pressure.

Description

Technical Field

[0001] The present invention relates to a method for controlling a steam pipeline network. The present invention also relates to a steam pipeline network. Background Art

[0002] In any chemical facility, there are various processes that use steam. This is generally applicable to various types of chemical facilities, and chemical facilities themselves are very extensive. For example, steam is used for saturated process streams, for reforming reactions, and for driving turbines to generate electrical power. Generally speaking, once steam is used for a specific process, it can no longer be used for a different process and is thus consumed by its use. Depending on the specific use of the steam, it may be necessary to keep the steam at a certain minimum pressure. Therefore, the demand for steam by a specific process is limited not only by the total energy of the steam supplied to the process, but also by the pressure at which the steam must be useful.

[0003] As described above, just as there are different processes that consume steam in a facility, there are usually also different sources of steam within or supplied to a chemical facility. These sources often differ both in the steam pressure they provide and in the total amount of steam they can provide (e.g., measured in energy). This may also mean that the operation of different steam sources differs in terms of the associated costs, such that high-pressure steam is more expensive than low-pressure steam. Summary of the Invention

[0004] In view of these circumstances, an object of the present invention is to provide a method for controlling a steam pipeline network that enables more efficient matching of steam sources and steam-consuming devices through the steam pipeline network. Another object of the present invention is to provide a steam pipeline network that enables more efficient matching of steam sources and steam-consuming devices through the steam pipeline network.

[0005] Regarding the method for controlling a steam pipeline network, the object of the present invention is achieved by a method for controlling a steam pipeline network having the features of claim 1. Regarding the steam pipeline network, the object of the present invention is achieved by a steam pipeline network having the features of claim 15.

[0006] The present invention is based on the recognition that steam with a relatively high pressure can be used in steam-consuming devices that typically require only steam with a lower pressure. Generally speaking, high-pressure steam is scarcer than low-pressure steam, which is why it is usually preferred to use it in processes that truly require high-pressure steam. However, in a system having multiple steam sources (which differ in pressure and may also differ in maximum steam supply capacity) and having multiple steam-consuming devices (which may have a steam demand that varies over time), it may sometimes be economical to use the higher-pressure steam in steam-consuming devices that can also be supplied with lower-pressure steam, even though this is counterintuitive based on the notion that the steam would be "wasted" by not fully utilizing its higher pressure. Of course, it is easier to obtain lower-pressure steam from higher-pressure steam than vice versa.

[0007] A method according to the present invention is used for controlling a steam pipeline network, wherein the steam pipeline network includes a plurality of sub-pipeline networks, wherein each sub-pipeline network is connected to a corresponding external steam generation source that supplies steam to the corresponding sub-pipeline network at a corresponding internal steam pressure, and wherein, for each sub-pipeline network, the corresponding internal steam pressure is different. In other words, each sub-pipeline network is a system of conduits, pipes, etc. for distributing steam that operates at a certain pressure (i.e., the internal steam pressure), and this pressure is different for any two sub-pipeline networks. The steam generation source can in principle be any kind of steam generation source. The steam generation source is external in the sense that the operation of the steam generation source is not controlled by the method according to the present invention. In other words, from the perspective of the steam pipeline network according to the present invention and the method according to the present invention, the pressure and quantity of the steam they supply are provided as they are. Nevertheless, the ability of the steam generation source to supply steam in a certain quantity or rate can vary over time. The steam generation source can also adjust its steam generation rate on its own based on the corresponding quantity of steam consumed. The external steam generation source itself can also be supplied by a single common steam or energy source. All that matters here is that, from the perspective of the steam pipeline network, the steam is provided at multiple steam pressures, and in the context of the present invention, the source corresponding to each steam pressure presents as a corresponding external steam generation source. Internally, the plurality of external steam generation sources can be interconnected in any way.

[0008] Certain methods for optimizing the fuel supply to a steam generator are known from the prior art. For example, US2004 / 0093124 A1 discloses a steam generation facility that includes a plurality of loads in the form of a boiler, a turbine, or a cooler. An optimization algorithm implements an optimal dynamic allocation of the fuel supply requirements for the loads by means of a model-based predictive controller. The predictive controller suitably senses the load requirements of the loads (e.g., pressure and / or fuel supply and / or temperature, etc.) and provides the predicted total load energy requirement to a real-time optimizer (RTO), which divides the total load energy requirement into individually allocated fuel supply requirements (or set points) for the respective loads according to the predicted target allocation. This concept located at the steam generation source can be added to the concept of the present invention in order to optimize steam production.

[0009] In the method according to the invention, the steam pipe network further includes a plurality of steam consumers, each steam consumer being supplied with steam by a respective sub-pipe network. In other words, each steam consumer (which in principle can be any kind of steam consumer) is supplied with steam by a specific sub-pipe network and is thus provided with steam having a specific internal steam pressure. More than one steam consumer can also be supplied by the same sub-pipe network. Additionally, some devices or configurations understood to represent steam consumers can also be supplied by a plurality of sub-pipe networks and are thus supplied with steam having more than one steam pressure. Such devices or configurations can also internally mix the supplied steam from different sub-pipe networks, i.e., steam at different pressures. Thus, in the sense of the present invention, such a device, configuration, or other equipment is understood to represent a plurality of steam consumers, i.e., one steam consumer for each steam pressure.

[0010] In the method according to the invention, the steam pipe network further includes at least one inter-network valve for interconnecting a respective pair of the plurality of sub-pipe networks. Thus, steam can be selectively released from one sub-pipe network to another through this valve. In particular, the at least one inter-network valve is configured to selectively transfer steam from a sub-pipe network having a higher internal steam pressure to a sub-pipe network having a lower internal steam pressure. In particular, the rate of steam released from one sub-pipe network to another through this valve can be controlled. Thus, the inter-network valve does not need to be binary in its operation.

[0011] The method according to the invention comprises: a) measuring the steam consumption data of each sub-network; b) predicting the future steam consumption rate of each sub-network based on the measured steam consumption data of each sub-network; and c) controlling the at least one inter-network valve based on the predicted future steam consumption rate for supplying steam from a sub-network having a higher internal steam pressure to a sub-network having a lower internal steam pressure. The steam consumption rate can be expressed in any suitable quantity and in any suitable unit. Predicting the future steam consumption rate of each sub-network can also be based on the measured steam consumption rate of at least one additional sub-network and preferably on the measured steam consumption rates of all sub-networks. Predicting the future steam consumption rate of each sub-network can also be based on any number of other factors, quantities and measurements. These can also be different for each sub-network. In particular, the current steam consumption data of each sub-network can be measured.

[0012] In this way, steam that does not need to be at the high pressure can be supplied to steam-consuming devices that also receive steam at a lower pressure. This allows for more efficient use of steam, especially for cases where the demand for steam at a higher pressure is temporarily reduced. Additionally or alternatively, the production rate of steam at a lower pressure may also be temporarily reduced. Therefore, when planning a facility, a steam network or a group of steam generation sources, less steam generation capacity may be required at lower steam pressure values, which also reduces the initial construction and ongoing maintenance costs.

[0013] A preferred embodiment of the method according to the invention is characterized in that the steam network comprises at least one steam buffer tank connected to the respective sub-networks for buffering steam at the respective internal steam pressure, and the method comprises: d) controlling the steam flow between the at least one steam buffer tank and the respective sub-networks based on the predicted future steam consumption rate. The steam flow between the at least one steam buffer tank and the respective sub-networks can flow in either direction. Thus, the at least one steam buffer tank can supply buffered steam to the respective sub-networks. The at least one steam buffer tank can also be supplied with steam from the respective sub-networks having steam. By using the steam buffer tank in this way, higher-pressure steam can be provided from the steam buffer to a sub-network having lower-pressure steam, thereby avoiding or reducing the need to increase steam production through a higher-pressure external steam generation source.

[0014] Another embodiment of the method according to the invention is characterized in that at least one steam-consuming device is operated as a device for producing chemical products or intermediates from one or more reactants, i.e., as a chemical reactor. Preferably, such a steam-consuming device includes a material buffer tank for the chemical product or intermediate. In the case where an excessive amount of steam is temporarily available, thus temporarily allowing an increase in the production rate, the material buffer tank can be used to buffer the over-produced product or intermediate. In the case of a temporary steam shortage in the sub-network to which the steam-consuming device is connected, the product or intermediate can be supplied to the steam-consuming device and / or any other facility component arranged downstream of the steam-consuming device in order to compensate for the reduction in the production rate caused by the steam shortage in the corresponding sub-network.

[0015] Another preferred embodiment of the method according to the invention is characterized in that at least one of the steam-consuming devices is a steam consumer-supplier which supplies steam to a sub-network at its respective internal steam pressure, the supplied sub-network being different from the sub-network supplying the steam consumer-supplier, the rate of steam supplied by the steam consumer-supplier to the sub-network depending on the steam consumption rate of the steam consumer-supplier, and the method comprising: e) controlling the steam consumption rate of the steam consumer-supplier and the rate of steam supplied by the steam consumer-supplier based on the predicted future steam consumption rate. In other words, the steam consumer-supplier is a steam-consuming device which not only consumes steam but also returns steam back to the steam network and is thus also a supply device. Generally, the steam returned to the steam network will have a lower steam pressure compared to the steam consumed. Therefore, it is preferred that the internal steam pressure of the sub-network supplied by the steam consumer-supplier is lower than the internal steam pressure of the sub-network supplying the steam consumer-supplier. The rate of steam supplied by the steam consumer-supplier to the sub-network can be proportional to the steam consumption rate of the steam consumer-supplier. In other words, there can be a substantially linear relationship between the rate of supplied steam and the rate of returned steam. Thus, such a consumer-supplier device can also be used to convert higher-pressure steam into lower-pressure steam. Preferably, the steam consumer-supplier includes a distillation column. As is well known in the art, distillation columns can be used for a variety of specific applications in chemical facilities.

[0016] According to a preferred embodiment of the method according to the invention, measuring the steam consumption data of each sub-network includes measuring the process data of each steam consumption device, and predicting the future steam consumption rate of each sub-network includes predicting the future steam consumption rate of each steam consumption device, which is based on the measured process data of the steam consumption device. In other words, the measurement and prediction are performed at the level of the individual steam consumption device, rather than at the level of the corresponding sub-network. In any case, predicting the future steam consumption rate of each sub-network or each steam consumption device can be further based on any additional data. Preferably, the current process data of each steam consumption device is measured, and predicting the future steam consumption rate of each steam consumption device is based on the measured current process data of the steam consumption device.

[0017] In principle, the process data can include any kind of data associated with the steam consumption device. According to a preferred embodiment of the method according to the invention, the process data of each steam consumption device includes the steam consumption rate, the energy consumption rate, a plurality of process pressure values, a plurality of process temperature values, and / or an ambient quantity of the steam consumption device. For example, the ambient quantity of the steam consumption device can include atmospheric or meteorological quantities, such as ambient temperature or ambient pressure. All of these variables can indicate the future steam consumption rate.

[0018] According to another preferred embodiment of the method according to the invention, predicting the future steam consumption rate of each steam consumption device is also based on the operating settings of the steam consumption device. Different from the process data (in a sense, which is measured by the steam consumption device and thus output), the operating settings are parameters input to the steam consumption device and can therefore be controlled by the user or an algorithm.

[0019] A preferred embodiment of the method according to the invention is characterized in that each sub-network includes a steam receiving valve that connects the corresponding sub-network to its corresponding connected external steam generation source, and the method further includes: controlling the steam receiving rate of at least one sub-network via the steam receiving valve based on the predicted future steam consumption rate. Thus, even if the amount of steam generated by the steam generation source may not be controlled, the amount of steam received by the corresponding sub-network can be controlled by the valve.

[0020] Another preferred embodiment of the method according to the invention is characterized in that each sub-pipeline network includes a steam supply valve that connects the corresponding sub-pipeline network to a steam consumption device supplied by the corresponding sub-pipeline network, and the method further includes: based on the predicted future steam consumption rate, controlling the steam consumption rate of at least one steam consumption device via the steam supply valve. In this way, the steam supplied to a specific steam consumption device can be reduced below the predicted consumption rate. This may be useful when it is more economical to keep the steam consumption of a specific process below the required level in order to be able to supply sufficient steam to different steam consumption devices.

[0021] According to a preferred embodiment of the method according to the invention, the method further includes controlling the steam consumption rate of at least one steam consumption device based on the predicted future steam consumption rate via the operating parameters of the at least one steam consumption device. Thus, when the predicted total steam consumption exceeds the supply, a specific steam consumption device can be adjusted so that its steam consumption is reduced. Alternatively, when the predicted total steam consumption is still below the supply, the operating settings can be adjusted to increase the steam consumption.

[0022] According to another preferred embodiment of the method according to the invention, predicting the future steam consumption rate of each sub-pipeline network, in particular predicting the future steam consumption rate of each steam consumption device, includes predicting the energy consumption rate of each steam consumption device. It has been found that expressing the steam consumption rate in terms of the energy consumption rate is particularly suitable for calculation. It is also preferred that predicting the energy consumption rate of each steam consumption device includes extrapolating based on the past energy consumption rate of the steam consumption device.

[0023] A preferred embodiment of the method according to the invention is characterized in that predicting the future steam consumption rate of each sub-pipeline network, in particular predicting the future steam consumption data of each steam consumption device, includes applying the measured steam consumption rate of each sub-pipeline network and preferably the measured process data to a prediction model. In principle, the prediction model can be any kind of model for predicting the future steam consumption rate. Preferably, the prediction model is obtained by training a statistical model. In this way, the historical dependence of the steam consumption rate can be reflected in the prediction model.

[0024] Another preferred embodiment of the method according to the invention is characterized in that the prediction model is obtained based on a random forest learning method, a neural network, a least absolute shrinkage and selection operator, and / or a support vector machine learning method.

[0025] The prediction model can also be determined by comparing different types of prediction models. According to a preferred embodiment of the method according to the invention, the prediction model has been obtained in the following manner: using different training algorithms to train a plurality of candidate prediction models, and selecting one candidate prediction model as the obtained prediction model. In particular, selecting the candidate prediction model as the obtained prediction model may include applying a residual function to each candidate prediction model. In other words, after training the prediction model, it is determined which trained model most closely matches the actual consumption rate. The residual function can be applied to the comparison between the candidate prediction model and the measured comparison data (which is different from the training data).

[0026] In principle, the difference in the internal vapor pressure can be arbitrarily large or small. A preferred embodiment of the method according to the invention is characterized in that the difference in the internal vapor pressure between at least two sub-pipe networks of the steam pipe network, preferably between any two sub-pipe networks, is at least 500 kPa (5 bar).

[0027] Another preferred embodiment of the method according to the invention is characterized in that for each external steam generation source, the maximum steam supply capacity (preferably expressed in power) is different. Thus, this power defines the energy of the supplied steam divided by time.

[0028] According to a preferred embodiment of the method according to the invention, the steam pipe network is included in a facility for a chemical production process. Preferably, at least one of the plurality of steam consumption devices is a process step of the chemical production process.

[0029] According to another aspect of the invention, the object on which the invention is based is solved by a steam pipe network comprising a plurality of sub-pipe networks.

[0030] In the steam pipe network according to the invention, each sub-pipe network is connected to a corresponding external steam generation source, which supplies steam to the corresponding sub-pipe network at a corresponding internal steam pressure, wherein for each sub-pipe network, the corresponding internal steam pressure is different.

[0031] The steam pipe network according to the invention further comprises a plurality of steam consumption devices, each steam consumption device being supplied with steam by a corresponding sub-pipe network, and the steam pipe network comprising at least one inter-network valve for interconnecting a corresponding pair of the plurality of sub-pipe networks.

[0032] The steam pipeline network according to the present invention further includes control equipment, which is configured to: a) measure the current steam consumption data of each sub-pipeline network; b) predict the future steam consumption rate of each sub-pipeline network based on the measured current steam consumption data of each sub-pipeline network; and c) control the at least one pipeline network valve based on the predicted future steam consumption rate to supply steam from a sub-pipeline network with a higher internal steam pressure to a sub-pipeline network with a lower internal steam pressure.

[0033] The preferred embodiments, features, and advantages of the steam pipeline network according to the present invention correspond to the preferred embodiments, features, and advantages of the method according to the present invention, and vice versa. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In the following description, additional advantages and preferred features are discussed with reference to the drawings. Shown below are:

[0035] Figure 1 An illustration of an embodiment of the steam pipeline network according to the present invention for implementing an embodiment of the method according to the present invention; and

[0036] Figure 2 An illustration of a data processing system for implementing an embodiment of the method according to the present invention for a steam pipeline network that can be used for Figure 1 the steam pipeline network. DETAILED DESCRIPTION

[0037] Figure 1 The steam pipeline network shown in is part of a chemical facility for a chemical production process and has three sub-pipeline networks 1a, 1b, 1c, where the first sub-pipeline network 1a has an internal steam pressure of 6 bar, the second sub-pipeline network 1b has an internal steam pressure of 16 bar, and the third sub-pipeline network 1c has an internal steam pressure of 31 bar. To maintain the respective internal steam pressures, each sub-pipeline network 1a-c is supplied with steam at a pressure corresponding to its respective internal steam pressure by a corresponding external steam generation source 2a-c. Each sub-pipeline network 1a-c is connected to its corresponding external steam generation source 2a-c through a corresponding steam receiving valve 13a-c. Although the steam pipeline network cannot control the rate of steam generation by the external steam generation sources 2a-c, the steam pipeline network can control the rate at which each sub-pipeline network 1a-c receives steam from its corresponding external steam generation source 2a-c through the steam receiving valve 13a-c. The control is performed by the control equipment 17 of the steam pipeline network.

[0038] The steam pipeline network further includes steam consumption devices 3a - f. Among them, the first steam consumption device 3a and the second steam consumption device 3b are supplied with steam at 6 bar by the first sub - pipeline network 1a. The third steam consumption device 3c and the fourth steam consumption device 3d are supplied with steam at 16 bar by the second sub - pipeline network 2b. And the fifth steam consumption device 3e and the sixth steam consumption device 3f are supplied with steam at 31 bar by the third sub - pipeline network 1c. The steam pipeline network includes six steam supply valves 14a - f that connect the corresponding sub - pipeline networks 1a - c to each steam consumption device 3a - f.

[0039] There is also a steam buffer tank 4 connected to the third sub - pipeline network 1c. Controlled by a valve system, the steam buffer tank 4 can buffer the steam from the third sub - pipeline network 1c. This valve system is in turn controlled by a control device 17. In other words, the steam buffer tank 4 can receive steam at 31 bar from the third sub - pipeline network 1c, thereby increasing its buffer filling level. And at a later time, it can supply the previously buffered steam at 31 bar to the third sub - pipeline network 1c to an extent corresponding to its filling level.

[0040] The control device 17 continuously measures the steam consumption rate of each steam consumption device 3a - f and other process data 6, including the energy consumption rate, the process pressure value, and the ambient temperature. This measurement of the respective steam consumption rates of the individual steam consumption devices 3a - f also provides steam consumption data 10 for each sub - pipeline network 1a - c. The third steam consumption device 3c is a distillation column 11 and thus presents as a steam consumption - supply device 12. That is to say, the steam consumption device 3c not only consumes steam from the second sub - pipeline network 1b, but also supplies steam to the first sub - pipeline network 1a. The reason is that the steam used in the distillation column 11 is not completely released or otherwise lost, but only the pressure is reduced. Therefore, the steam consumed by the distillation column 11 can be recovered at a lower pressure and can be used at this lower pressure for other steam consumption devices. The rate at which the distillation column 11 supplies steam to the first sub - pipeline network 1a is linearly proportional to the rate at which the distillation column 11 consumes steam.

[0041] The steam pipeline network further includes a first inter-network valve 5a connecting the first sub-pipeline network 1a and the second sub-pipeline network 1b, and a second inter-network valve 5b connecting the second sub-pipeline network 1b and the third sub-pipeline network 1c. The first inter-network valve 5a and the second inter-network valve 5b are pressure reducing valves. The first inter-network valve 5a allows steam to be supplied from the second sub-pipeline network 1b at 16 bar to the first sub-pipeline network 1a at 6 bar. The second inter-network valve 5b allows steam to be supplied from the third sub-pipeline network 1c at 31 bar to the second sub-pipeline network 1b at 16 bar. Thus, a higher demand for steam at a location with a lower internal steam pressure in the sub-pipeline networks 1a-c can be met by using steam from a sub-pipeline network 1a-c with a higher internal steam pressure. Another interconnecting valve (not shown) can also be installed, which connects the first sub-pipeline network 1a and the third sub-pipeline network 1c, and thus skips the second sub-pipeline network 1b that requires stronger pressure reduction, i.e., in the current case, reducing from 31 bar in the third sub-pipeline network 1c to 6 bar in the first sub-pipeline network 1a.

[0042] As Figure 2 shown, based on the measured process data 6 of each steam consumption device 3a-f, steam consumption data 10 for each of the sub-pipeline networks 1a-c during the observation time are obtained, and both of them are then applied to the prediction model 7. The prediction model 7 runs on a computer system 16 and has been obtained based on a neural network that is trained using the long-term historical process data 8 of each steam consumption device 3a-f. It selects the most accurate prediction model from among three candidate prediction models 15a-c, as measured by a residual function applied to the predictions generated by each candidate prediction model 15a-c. Additionally, the current operating settings of each steam consumption device 3a-f (which correspond to values input by the respective operators of the steam consumption devices 3a-f) are also applied to the prediction model 7.

[0043] The prediction model 7 provides a predicted future steam consumption rate for each steam consumption device 3a-f, based on which the future steam consumption rates 9 for each of the sub-pipeline networks 1a-c are then calculated. The prediction model 7 can provide such predictions because the neural network can reveal the correlation between the process data 6 of the steam consumption devices 3a-f and the subsequent steam consumption rates. For example, several chemical production processes follow a specific cycle, where a peak in the steam consumption of a certain steam consumption device 3a-f is followed by a peak in the steam consumption rate of a specific different steam consumption device 3a-f after a certain time.

[0044] Now, based on the predicted future steam consumption rates 9 for each sub-network 1a-c, the inter-network valves 5a, b are controlled by the control device 17 to compensate for the predicted demand peaks for a sub-network 1a-c. For example, when a demand peak is predicted at the first sub-network 1a (caused by the predicted steam consumption peak of the first steam consumption device 3a), higher-pressure steam from the second sub-network 1b can be supplied to the first sub-network 1a by means of the first inter-network valve 5a. When the predicted steam consumption rate at the second sub-network 1b is lower than the steam generation capacity of the second steam generation source 2b during the predicted demand peak time at the first sub-network 1a, the predicted steam consumption peak can be met without additional steam from the first steam generation source 2a. Similarly, to meet the predicted demand peak at the second sub-network 1b, higher-pressure steam from the third sub-network 1c can be supplied by means of the second inter-network valve 5b.

[0045] In addition to controlling the inter-network valves 5a, b, the control device 17 also takes additional measures to meet any predicted demand peaks. When the predicted steam consumption of the third sub-network 1c is low, the steam buffer tank 4 is filled with steam. When the predicted steam consumption rate of the third sub-network 1c is high, or when the predicted steam consumption rate of the first sub-network 1a or the second sub-network 1b is high but it will be supplied by the third sub-network 1c and the inter-network valves 5a, b, the steam buffer tank 4 supplies the previously buffered steam to the third sub-network 1c. In addition, the steam consumption rate of the distillation column 11 is controlled so as to also control its rate of supplying steam to the first sub-network 1a. The steam receiving rate of each sub-network 1a-c is controlled by means of the steam receiving valves 13a-c. Similarly, the steam consumption rate of each steam consumption device 3a-f is controlled either by controlling the corresponding steam supply valve 14a-f or by controlling the operating settings of the steam consumption devices 3a-f. The combination of the measures mentioned is used to balance the supply and demand of each sub-network 1a-c.

[0046] As described above, the steam network cannot control the rate at which the external steam generation sources 2a-c generate steam. Instead, the rate at which each sub-network 1a-c receives steam from the corresponding external steam generation source 2a-c is controlled by the steam network by means of the steam receiving valves 13a-c.

[0047] However, in Figure 1In another improvement scheme of the steam pipeline network (not shown, but described, for example, in US 2004 / 0093124A1), the steam generation process is also optimized in such a way that an optimal dynamic allocation of the fuel supply requirements for the steam generators 2a-c is implemented by means of a model-based predictive controller. Here, the predictive controller appropriately senses the energy requirements of the steam generators 2a-c and provides the predicted total load energy requirement to a real-time optimizer (RTO), which divides the total load energy requirement into separately allocated energy requirements for each of the steam generators 2a-c according to the predicted target allocation.

[0048] Although the present invention can be further improved by implementing the above optimization of the energy requirement allocation for the steam generators 2a-c, the steam pipeline network according to the present invention focuses on steam consumption. This is achieved by sensing a plurality of consumption rates and predicting the future steam consumption rates of each of the steam consumption devices 3a-f, and then calculating the future steam consumption rates 9 of each of the sub-pipeline networks 1a-c accordingly. This enables consumption to be transferred between the sub-pipeline networks 1a-c by means of the inter-network valves 5a, b.

Claims

1. A method for controlling a steam pipeline network, wherein, The steam pipeline network includes a plurality of sub-pipeline networks (1a-c), wherein each sub-pipeline network (1a-c) is connected to a corresponding external steam generation source (2a-c), and the external steam generation source (2a-c) supplies steam to the corresponding sub-pipeline network (1a-c) at a corresponding internal steam pressure. For each sub-pipeline network (1a-c), the corresponding internal steam pressure is different. The steam pipeline network further includes a plurality of steam consumption devices (3a-f), and each steam consumption device (3a-f) is supplied with steam by a corresponding sub-pipeline network (1a-c). The steam pipeline network further includes at least one inter-network valve (5a, 5b) for interconnecting a corresponding pair of the plurality of sub-pipeline networks (1a-c). The method includes: a) Measuring the steam consumption data (10) of each sub-pipeline network (1a-c); b) Predicting the future steam consumption rate (9) of each sub-pipeline network (1a-c) based on the measured steam consumption data (10) of each sub-pipeline network (1a-c); and c) Controlling the at least one inter-network valve (5a-b) based on the predicted future steam consumption rate (9) for supplying steam from a sub-pipeline network (1a-c) having a higher internal steam pressure to a sub-pipeline network (1a-c) having a lower internal steam pressure.

2. The method according to claim 1, wherein The steam pipeline network includes at least one steam buffer tank (4) connected to a corresponding sub-pipeline network (1a-c) for buffering steam at the corresponding internal steam pressure, and the method includes: d) Controlling the steam flow between the at least one steam buffer tank (4) and the corresponding sub-pipeline network (1a-c) based on the predicted future steam consumption rate (9).

3. The method according to claim 1 or 2, characterized in that, At least one of the steam consumption devices (3a-f) is a steam consumption-supply device (12), and the steam consumption-supply device (12) supplies steam at its corresponding internal steam pressure to a sub-pipeline network (1a-c) different from the sub-pipeline network (1a-c) that supplies the steam consumption-supply device (12). The rate of steam supplied by the steam consumption-supply device (12) to the sub-pipeline network (1a-c) depends on the steam consumption rate of the steam consumption-supply device (12), and the method includes: e) Controlling the steam consumption rate of the steam consumption-supply device (12) and the rate of steam supplied by the steam consumption-supply device (12) based on the predicted future steam consumption rate. Preferably, the steam consumption-supply device (12) includes a distillation column (11).

4. The method according to any one of claims 1 to 3, characterized in that, Measuring the steam consumption data (10) of each sub-pipeline network (1a-c) includes measuring the process data (6) of each steam consumption device (3a-f), and predicting the future steam consumption rate (9) of each sub-pipeline network (1a-c) includes predicting the future steam consumption rate (9) of each steam consumption device (3a-f) based on the measured process data (6) of the steam consumption device (3a-f).

5. The method according to claim 4, characterized in that, The process data (6) of each vapor-consuming device (3a-f) includes the vapor consumption rate, energy consumption rate, a plurality of process pressure values, a plurality of process temperature values, and / or ambient quantities of the vapor-consuming device.

6. The method according to claim 4 or 5, characterized in that, Predicting the future vapor consumption rate (9) of each vapor-consuming device (3a-f) is also based on the operating settings of the vapor-consuming device (3a-f).

7. The method according to any one of claims 1 to 6, characterized in that, Each sub-network (1a-c) includes a vapor receiving valve (13a-c) that connects the respective sub-network (1a-c) to its respective connected external vapor generation source (2a-c), and the method further includes controlling the vapor receiving rate of at least one sub-network (1a-c) via the vapor receiving valve (13a-c) based on the predicted future vapor consumption rate (9).

8. The method according to any one of claims 1 to 7, characterized in that, Each sub-network (1a-c) includes a vapor supply valve (14a-f) that connects the respective sub-network (1a-c) to the vapor-consuming device (3a-c) supplied by the respective sub-network (1a-c), and the method further includes controlling the vapor consumption rate of at least one vapor-consuming device (3a-f) via the vapor supply valve (14a-f) based on the predicted future vapor consumption rate (9).

9. The method according to any one of claims 1 to 8, characterized in that, The method further includes controlling the vapor consumption rate of the at least one vapor-consuming device (3a-f) via the operating settings of the at least one vapor-consuming device (3a-f) based on the predicted future vapor consumption rate (9).

10. The method according to any one of claims 1 to 9, characterized in that, Predicting the future vapor consumption rate (9) of each sub-network (1a-c) includes predicting the energy consumption rate of each vapor-consuming device (3a-f), preferably, wherein predicting the energy consumption rate of each vapor-consuming device (3a-f) includes extrapolating based on the past energy consumption rate of the vapor-consuming device (3a-f).

11. The method according to any one of claims 1 to 10, characterized in that, Predicting the future vapor consumption rate (9) of each sub-network (1a-c) includes applying the measured vapor consumption data (10) of each sub-network (1a-c), preferably the measured process data (6), to a prediction model (7), preferably, the prediction model (7) is obtained by training a statistical model, in particular, the prediction model (7) is obtained based on a random forest learning method, neural network, least absolute shrinkage and selection operator, and / or support vector machine learning method.

12. The method according to claim 11, wherein The prediction model (7) is obtained by using different training algorithms to train a plurality of candidate prediction models (15a-c), and by applying a residual function to each candidate prediction model (15a-c), selecting one candidate prediction model (15a-c) as the obtained prediction model.

13. The method according to any one of claims 1 to 12, characterized in that, For each external vapor generation source (2a-c), the maximum vapor supply capacity, preferably expressed in power, is different.

14. The method according to any one of claims 1 to 13, characterized in that, The vapor network is included in a facility for a chemical production process, preferably, at least one of the plurality of vapor-consuming devices (3a-f) is a process step of the chemical production process.

15. Steam pipe network, which includes a plurality of sub-pipe networks (1a-c), wherein, Each sub-pipeline network (1a-c) is connected to a corresponding external steam generation source (2a-c), and the external steam generation source (2a-c) supplies steam to the corresponding sub-pipeline network (1a-c) at a corresponding internal steam pressure, wherein for each sub-pipeline network (1a-c), the corresponding internal steam pressure is different. The steam pipeline network further includes a plurality of steam consumption devices (3a-f), each steam consumption device (3a-f) being supplied with steam by a corresponding sub-pipeline network (1a-c). The steam pipeline network further includes at least one inter-network valve (5a, 5b) for interconnecting a corresponding pair of the plurality of sub-pipeline networks (1a-c). The steam pipeline network further includes a control device (17), the control device being configured to: a) measure steam consumption data (10) of each sub-pipeline network (1a-c); b) predict a future steam consumption rate (9) of each sub-pipeline network (1a-c) based on the measured steam consumption data (10) of each sub-pipeline network (1a-c); and c) control the at least one inter-network valve (5a-b) based on the predicted future steam consumption rate (9) for supplying steam from a sub-pipeline network (1a-c) having a higher internal steam pressure to a sub-pipeline network (1a-c) having a lower internal steam pressure).

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