METHOD FOR OPERATING A SORPTION PLANT AND SORPTION PLANT

Description

[0001] The invention relates to a method for operating a sorption plant, an arrangement for a sorption plant and a sorption plant. background

[0002] The demand for cooling energy, and thus the overall energy demand, is steadily increasing due to increased workplace requirements and desire for comfort, the need to refrigerate food, and also the cooling and temperature control of temperature-sensitive production processes. In the field of building technology, annual growth rates of 8% to 12% are currently being recorded. This makes refrigeration technology one of the fastest-growing energy consumers in the building sector worldwide.

[0003] The typically fluctuating loads in building cooling, coupled with the increasingly flexible energy supply levels in utility structures, require new storage concepts to store this energy either on the primary energy source side (electricity, heat) or on the energy user side (mobility, heat, cold). Heat and cold storage systems differ primarily in the temperature level of the energy to be stored.

[0004] Storage technologies for heat or cold storage can generally be divided into three groups: sensible storage, latent storage, and thermochemical storage. Sensible storage uses liquid or solid storage media and utilizes the range between two temperature levels to store energy. The most common examples are hot and cold water storage. In latent storage, the latent heat during phase transitions (solid-liquid or liquid-gas) is used to store energy. In particular, latent storage systems using a phase-changing material (PCM) for storage with higher energy densities are available on the market. In the area of ​​latent storage, the best-known and most environmentally safe PCM is ice water or so-called ice slurry. Paraffins and similar substances are also used to enable a phase change at the desired temperature level.Finally, thermochemical storage can be divided into chemical storage and sorption storage, and the latter into absorption storage and adsorption storage.

[0005] Storage presents a particular challenge in refrigeration technology. For operating temperatures, which in building technology are often between approximately 5 °C and 9 °C, sensitive water storage tanks are generally used. Unlike in heating technology, where a temperature range of 30 K to 50 K between a charged and discharged storage tank can often be used, for a cold water storage tank with operating temperatures of 5 °C to 9 °C, this range is only a few Kelvin, as the storage tank must, on average, have a lower temperature level than the operating temperature. This reduces the thermal storage capacity to approximately 5% to 15% compared to a hot water storage tank.

[0006] Alternatively, ice storage systems can be used. These function even when operating temperatures around freezing point must be provided and have a significantly higher energy storage density. To prevent the storage medium from freezing, cold brine must be used instead of cold water, which may require a system separation from the building in air conditioning applications. Ice storage systems are particularly suitable for operating temperatures around 0°C. This also applies to operating temperatures above 4°C to 5°C if high energy densities are desired. However, if cost efficiency is a priority, sensitive storage systems are preferable. At approximately 200 kJ / kg, the storage density of an ice storage system is about ten times that of a sensitive water storage system for storing cold water. However, at higher operating temperatures, the efficiency of cooling generation for charging an ice storage system decreases compared to sensitive storage.PCM storage systems for other phase change temperatures (e.g. 10 °C) also exist, but such storage systems have not yet become established due to their current costs, technical feasibility and lower energy densities compared to ice storage systems.

[0007] There is therefore a need for additional cold storage technology. Such technologies are also of interest in connection with cold generation, such as absorption chillers.

[0008] In conventional absorption chillers, the absorber and condenser are connected to the same heat sink circuit / cooling fluid circuit for heat removal. Cooling fluid from the cooling fluid circuit often flows through the absorber first, followed by the condenser. In some systems, the condenser is also flowed through first, followed by the absorber, or both are flowed through in parallel. In any case, however, conventional absorption chillers are operated in such a way that the flow regime is already specified by the manufacturer of the absorption chiller, and a varying supply of cooling fluid during operation is not possible separately for either the absorber or the condenser.

[0009] To compensate for differences between generator output and consumer load, and to cover loads that cannot be covered by the generators, storage units (usually sensitive storage units) are also installed in absorption refrigeration systems. These units are charged by the generators when the consumer load is low and discharged when the consumer load exceeds the generation capacity.

[0010] Document EP 0 152 931 A2 discloses a method for operating a monovalent generator-absorption heat pump heating system for space heating and hot water preparation. To provide a multi-stage, periodically operating absorption heat pump with a small number of devices and while avoiding vulnerable, maintenance-intensive, and energy-consuming components or units, a periodic alternation of an operating phase of expulsion with condensation and evaporation with absorption at different pressure levels is provided. EP 0 152 931 A2 discloses a method according to the preamble of claim 1; and a device according to the preamble of claim 13.

[0011] Document JP S 5 339 360 U relates to a double-acting absorption chiller which uses water as a refrigerant and a salt solution as an absorbent, so that the start-up time required for operation and start-up can be reduced, in particular by improving the start-up characteristics.

[0012] Document US 2019 / 128582 A1 discloses a method for operating an absorption heat pump system, particularly with regard to the flow of hydronic cooling fluid through a condenser during system start-up or when the cooling fluid temperature is low. To minimize the time required for an absorption heat pump to reach maximum cooling or heating capacity, it is desirable for a pressure on the high-pressure side to rise as quickly as possible and a further pressure on the low-pressure side to fall as quickly as possible. Summary

[0013] The object of the invention is to provide a method for operating a sorption plant and an arrangement for a sorption plant with which additional heat and / or cold storage is achieved in a compact and cost-effective manner.

[0014] To solve this problem, a method for operating a sorption system and an arrangement for a sorption system are provided according to independent claims 1 and 13. Further embodiments are the subject of dependent subclaims. According to one aspect, a method for operating a sorption system is provided. The sorption system has a cooling fluid circuit with a cooling fluid; a process medium circuit with a refrigerant and a solvent; an absorber connected to the cooling fluid circuit and the process medium circuit; a condenser connected to the cooling fluid circuit and the process medium circuit; and a control device.During operation of the sorption plant, the cooling fluid is supplied to the absorber and the condenser, and by means of the control device, a supply of the cooling fluid to the absorber and a supply of the cooling fluid to the condenser are regulated differently from one another, wherein a flow ratio for a flow of the cooling fluid through the absorber and a flow of the cooling fluid through the condenser is regulated, wherein the supply of the cooling fluid to the absorber and the supply of the cooling fluid to the condenser are regulated independently of one another.

[0015] According to another aspect, an arrangement is provided which comprises the following: a cooling fluid circuit with a cooling fluid; a process medium circuit with a refrigerant and a solvent; an absorber which is connected to the cooling fluid circuit and the process medium circuit; a condenser which is connected to the cooling fluid circuit and the process medium circuit; and a control device which is configured, during operation of the sorption system, to control a supply of the cooling fluid to the absorber and a supply of the cooling fluid to the condenser differently from one another and a flow ratio for a flow of the cooling fluid through the absorber and a flow of the cooling fluid through the condenser, wherein the control device is configured to control the supply of the cooling fluid to the absorber and the supply of the cooling fluid to the condenser independently of one another.

[0016] According to a further aspect, a sorption system is created with the arrangement.

[0017] By means of different control of the supply of cooling fluid to the absorber and the supply of cooling fluid to the condenser, a complete and / or at least partial decoupling of the cooling fluid flows to the absorber and the condenser is achieved.

[0018] The process is in principle suitable for all continuously operating sorption plants for heat and / or cold generation that use a thermal compressor and a sorbent and a sorbent (or solvent and refrigerant) as operating media.

[0019] The process makes it possible to eliminate the division between cold generator and cold storage (or heat generator and heat storage) and to combine these technical areas and their system technologies. The function performed by conventional cold storage in low-temperature heating circuits can be fully or partially covered by the independent control of the cooling fluid circuit. The process thus enables the additional use of the absorption chiller as a power-dense storage system. Consequently, the installation of a separate dedicated cold storage system can be dispensed with. Likewise, a possible hot water storage tank could be partially or completely replaced. Furthermore, installation space is saved, which is often at a premium in energy centers. The difference in volumetric power density is approximately 100. The gravimetric power density is approximately 100% higher than with a reference storage tank.1 m3< water volume even at a factor of approximately 200, since a large proportion of storage material becomes unnecessary here. For larger storage tanks, this factor decreases gradually, but generally will not be less than 150. It is also important that sorption systems such as absorption chillers can be retrofitted to existing systems with little effort.

[0020] The process is independent of the performance range or the design of the sorption plant.

[0021] The process can be operated with any common solvent and / or refrigerant. Lithium bromide can be used as the solvent and water as the refrigerant. Alternatively, the process can be used in ammonia-water systems, for example.

[0022] The process can be operated at different temperature levels of connected heat sources and heat sinks. The temperature level of the low-temperature heat source can be between -40 °C and 20 °C, in particular between 5 °C and 16 °C for building cooling or between -10 °C and 5 °C for food and pharmaceutical cooling. The temperature level of the heat sink can be between 15 °C and 80 °C, in particular between 25 °C and 60 °C, preferably 30 °C. In principle, however, the heat sink can also assume other temperatures. The temperature level of the high-temperature heat source can be between 35 °C and 160 °C, in particular between 55 °C and 110 °C, preferably 90 °C. Higher temperatures of the high-temperature source are also possible.

[0023] The sorption system can comprise a cooling fluid circuit with a cooling fluid; a process fluid circuit with a refrigerant and a solvent; an absorber connected to the cooling fluid circuit and the process fluid circuit; a condenser connected to the cooling fluid circuit and the process fluid circuit; and a control device. During operation of the sorption system, the cooling fluid can be supplied to the absorber and the condenser, and a supply of the cooling fluid to the absorber and a supply of the cooling fluid to the condenser are individually controlled by the control device. By controlling the supply of the cooling fluid to the absorber and the supply of the cooling fluid to the condenser by the control device, an inlet temperature of the cooling fluid to the absorber and an inlet temperature of the cooling fluid to the condenser can be controlled independently of one another.

[0024] In a first state of the control device compared to a base state of the control device, the supply of the cooling fluid to the absorber can be reduced and / or the supply of the cooling fluid to the condenser can be increased.

[0025] In the first state of the control system, the refrigerant concentration in a section of a solvent circuit formed in the process fluid circuit and containing the solvent can be reduced. By reducing the supply of cooling fluid to the absorber, the heat transfer value in the absorber can be reduced and / or the temperature of the cooling fluid in the absorber can be increased relative to the baseline.

[0026] The sorption system may include a desorber connected to the solvent circuit. Refrigerant expulsion in the desorber can be reduced by increasing the refrigerant concentration compared to the baseline of the control system. Refrigerant expulsion in the desorber can also be reduced by lowering the vapor phase equilibrium pressure in the desorber.

[0027] By increasing the supply of cooling fluid to the condenser, the heat transfer value in the condenser can be increased and / or the temperature of the cooling fluid at the inlet to the condenser can be reduced.

[0028] In the first state of the control device, the refrigerant supply to the condenser can be increased compared to the base state of the control device, and the refrigerant can then be stored in a storage device connected to the process fluid circuit. The storage device can, in particular, be part of the process fluid circuit. By storing the refrigerant, latent storage of cold can occur in the form of a liquid-gas phase change.

[0029] In a second state of the control device, the supply of the cooling fluid to the absorber can be increased compared to the basic state of the control device and / or the supply of the cooling fluid to the condenser can be reduced.

[0030] In the second state of the control device, the refrigerant can be released from the storage device.

[0031] The sorption system can have an evaporator connected to the process fluid circuit. In the second state of the control system, the refrigerant can be supplied from the storage device to the evaporator, and heat from a low-temperature heat source can be transferred to the refrigerant via the evaporator.

[0032] The storage device can be arranged at least partially in the evaporator. In particular, the storage device can be arranged entirely in the evaporator. The storage device can also be arranged at least partially outside the evaporator.

[0033] In the cooling fluid circuit, the cooling fluid can be fed via an absorber section to the absorber and via a condenser section to the condenser. The condenser section and absorber section can be connected to the control device.

[0034] The supply of cooling fluid to the absorber section can be controlled by at least one first flow-regulating component of the control device. Furthermore, the supply of cooling fluid to the condenser section can be controlled by at least one second flow-regulating component of the control device.

[0035] In connection with the arrangement for a sorption system and the sorption system, the configurations described above in connection with the method for operating a sorption system can be provided accordingly. Description of implementation examples

[0036] Further embodiments are explained in more detail below with reference to the figures of a drawing. Herein: Fig. 1 is a schematic representation of a sorption system; Fig. 2 is a pressure-temperature diagram illustrating an absorption refrigeration system process; Fig. 3 is a schematic representation for controlling a cooling fluid circuit for a sorption system; Fig. 4 is a schematic representation of an embodiment of a sorption system with an arrangement according to the invention for carrying out a method according to the invention; Fig. 5 is a schematic representation of a further embodiment of a sorption system not according to the invention; and Fig. 6 is a schematic representation of a further embodiment of a sorption system with an arrangement according to the invention for carrying out a method according to the invention.

[0037] Fig. 1shows a schematic representation of a sorption system in the form of an absorption refrigeration system 1 with an evaporator 2, an absorber 3, a desorber 4 and a condenser 5, each of which is connected to a process medium circuit 6.

[0038] Refrigerant and solvent are conducted through the process medium circuit 6. A solvent circuit 6a, to which the absorber 3 and the desorber 4 are connected, also carries a solution containing solvent in which the refrigerant can be dissolved. The solvent circuit 6a is operated by a pump 6b, and a section (refrigerant circuit) 6c of the process medium circuit 6, which generally contains little or no solvent, is operated by a pump 6d. Refrigerant vapor 6e is conducted from the evaporator 2 into the absorber 3 and from the desorber 4 into the condenser 5. Liquid refrigerant is also conducted from the condenser 5 into the evaporator 2 via section 6f.

[0039] The desorber 4 is connected to a high-temperature circuit 7, via which heat from a high-temperature heat source 7a is supplied to expel the refrigerant vapor in the desorber 4.

[0040] A control system is present (often designed as a combination of a pump and a valve, see also Fig. 3 with pump 30 and valve 33) to regulate the temperature and / or quantity of the fluid from the (external) high-temperature heat source 7a, which is fed to the desorber 4.

[0041] The waste heat from the absorber 3 and condenser 5 is dissipated by means of cooling fluid via a heat sink circuit / cooling fluid circuit 8 to a heat sink 8a. This is done using a pump, a bypass, and a valve (see Fig. 4 with pump 44, bypass 39 and valve 34).

[0042] The absorption refrigeration system 1 cools a low-temperature heat source 9a by extracting heat from the low-temperature heat source 9a via a low-temperature circuit 9 to which the evaporator is connected.

[0043] Furthermore, a throttle 10 is provided in the refrigerant circuit 6c, and a solution heat exchanger 11 is provided in the solvent circuit 6a. The evaporator 2 and the absorber 3 are arranged in a common housing 12, and the desorber 4 and the condenser 5 are arranged in a common housing 13. The housings 12, 13 can be cylindrical, for example. Alternatively, the evaporator 2, the absorber 3, the desorber 4, and the condenser 5 are not arranged in separate housings.

[0044] Fig. 2A pressure-temperature diagram schematically illustrates the location of the process and solution field, as well as the refrigerant, within an absorption chiller process. The respective process sections at the evaporator 2, the absorber 3, the desorber 4, and the condenser 5 are labeled E, A, D, and C, respectively.

[0045] In this example, water acts as the refrigerant and lithium bromide (LiBr) as the solvent. The following information describes a possible operating point. The low-temperature heat source 9a is operated at 6 °C, the heat sink 8a at 30 °C, and the high-temperature heat sources at 90 °C. The absorption chiller is operated at pressures p between an evaporator pressure / evaporator pressure p E and condenser pressure PC operated.

[0046] Lines / isosteres 20 represent regions of equal solvent concentration. At the same pressure, the concentration increases with increasing temperature. Isostere 20a corresponds to pure water without LiBr. Point 21 represents the triple point of water. Crystallization occurs to the right of crystallization line 22 (depending on pressure and temperature). This crystallization line shifts with higher pressures and higher temperatures to higher concentrations, relative to the amount of LiBr in solution, at which crystallization only begins. Solution with a low water concentration / high LiBr concentration flows from the desorber to the absorber (process layer line 23), and solution with a higher water concentration flows from the absorber to the desorber (process layer line 24).

[0047] The location of the process's key points and the location of the solution field are determined by the heat transfer values ​​(UA values) of the heat exchangers (in evaporator 2, absorber 3, desorber 4, and condenser 5) and the respective external temperatures. For each individual heat exchanger, the temporal change in the amount of heat transferred is proportional to the heat transfer coefficient. U, to the area A of the heat exchanger and to the logarithmic temperature difference Δ T log is: Q ˙ = U ⋅ A ⋅ Δ T log .

[0048] The four heat exchangers and the heat transfer taking place there are constantly interdependent. The difference between the process temperatures and the temperatures of the heat sources 7a, 9a and the heat sink 8a is determined by the respective heat transfer values. U · Aand is essentially determined only by the operation and the specified volume flows of the external fluids (fluids in the heat sink, high-temperature or low-temperature circuit).

[0049] The UA values ​​and their ratios between absorber, desorber, condenser, and evaporator of different absorption chillers vary, and the UA values ​​of a system type can also vary slightly depending on the application, and even within an installation during different operating phases due to external conditions. For example, different temperatures of the heat sink 8a, such as those that occur in absorption chillers due to operation at different ambient temperatures, affect the material properties of the cooling brine and thus influence (within certain limits) the UA value. The same applies to changes in the high- and low-temperature circuits. The process conditions, temperatures, and concentrations also affect the material properties of the process fluids and thus the respective process-side heat transfer value, which in turn influences the U-value.The same applies if the flow rates of the external fluids differ between two operating points. In a state-of-the-art system, the flow rates of absorber 3 and condenser 5 cannot be controlled separately, and their inlet and / or outlet temperatures are directly linked. Even if the flow rates and / or temperatures are not equal, they cannot be adjusted separately according to the state of the art.

[0050] Fig. 3shows a schematic representation for controlling the cooling fluid circuit 8 for the sorption system 1 with evaporator 2, absorber, desorber 4, and condenser 5. A pump 30 is provided here to operate the high-temperature circuit 7, and pumps 31, 32 are provided here to operate the low-temperature circuit 9. Furthermore, valves 33, 34 can be provided to control volume flows and / or inlet temperatures into the sorption system 1. A storage tank 35, designed, for example, as a pendulum storage tank, can be provided in the low-temperature circuit 9. Furthermore, different volume flows can be decoupled via the sorption system 1 and the user circuit using the storage tank 35, and the storage tank 35 can be charged or discharged via this.

[0051] A control device 36 is arranged in the cooling fluid circuit 8, preferably between an absorber section 37 of the cooling fluid circuit 8 at the absorber 3 or a condenser section 38 of the cooling fluid circuit 8 at the condenser 5 on one side and the heat sink 8a on the other side. The control device 36 can have at least one pump. Additionally or alternatively, a pump can also be arranged in the cooling fluid circuit outside the control device 36 (not shown). According to the invention, the control device allows the cooling fluid flows to the absorber 3 of the cooling fluid circuit and to the condenser 5 to be controlled independently of one another.

[0052] The control device 36 is arranged in the cooling fluid circuit 8 parallel to a bypass section 39. The ratio of the supply of cooling fluid to the heat sink 8a and the supply of cooling fluid to the bypass section 39 is regulated by means of the valve 34. In this way, the supply of cooling fluid to the control device 36 can be regulated. Alternatively, no corresponding bypass section 39 can be provided in the cooling fluid circuit 8 (see FIG. Fig. 6 ). The bypass section 39 can also be arranged within the control device 36.

[0053] Fig. 4 shows a schematic representation of an embodiment of the control device 36 according to the invention.

[0054] The same cooling fluid flows through the absorber 3 and the condenser 5 one after the other (serial arrangement with a possible parallel portion). Two controllable valves 40, 41 are provided, which allow the flow of cooling fluid through the absorber 3 and the condenser 5 to be independently varied during operation, and thus the UA values ​​of the absorber 3 and the condenser 5 to be independently varied. In this way, in a first state of the control device 36, with a fully or partially active bypass around the absorber 3 (so that less or no cooling fluid flows to the absorber in the absorber section 37), the dissolution field is shifted to higher solvent concentrations.

[0055] The refrigerant expelled compared to a reference state with a closed bypass is collected, for example, in a region of the evaporator 2. Additionally or alternatively, the refrigerant is collected in the condenser or a third location. The released refrigerant is not used in the first state of the control device 36 and thus effectively represents a quantity of cold stored in the absorption chiller 1.

[0056] The stored amount of cold can be retrieved in a second state of the control device 36 by means of a relative increase in the supply of cooling fluid to the absorber compared to the supply to the condenser (compared to the process of storing the coolant in the first state of the control device 36 or compared to the basic state of the control device 36) and used in the evaporator 2 to generate cold, up to a complete or partial active bypass around the condenser 5 and the condenser section 38. In the case of a LiBr absorption refrigeration system, the amount of energy stored per unit of water (refrigerant) corresponds to about ten times that of an ice storage tank and about one hundred times that of a conventional sensible cold water storage tank.

[0057] In addition, from the reference state, by increasing the supply of cooling fluid to the absorber 3 compared to the supply to the condenser 5, a quantity of refrigerant already present in the storage device or the process medium circuit 6 can also be used for additional cooling generation (compared to the reference state), which can be refilled at a different time.

[0058] Not according to the invention, only a single effectively controllable bypass can be used, preferably around the absorber 3 and the absorber section 37, in order to regulate the ratio of the supply of cooling fluid or the flow of cooling fluid between the absorber 3 and the condenser 5. For this purpose (to increase the amount of refrigerant in the refrigerant circuit 6c), the valve 40 is controlled such that a valve outlet 42 is opened further for discharging. Alternatively, and also not according to the invention, only one effective bypass can be provided around the condenser 5 and the condenser section 38. For this purpose, the valve 41 is controlled such that a valve outlet 43 is opened further for charging.

[0059] Preferably, the cooling fluid flows through the absorber 3 first, followed by the condenser 5. Alternatively, the cooling fluid can flow through the condenser 5 first, followed by the absorber 3. The flow direction and flow rate of the cooling fluid can be regulated by a pump 44.

[0060] Fig. 5 shows a schematic representation of an embodiment of the control device 36 not according to the invention. Only one actively controllable valve 50 is provided, which regulates the ratio of cooling fluid flowing through the absorber section 37 and the condenser section 38. The absorber section 37 and the condenser section 38 are arranged in a parallel flow arrangement. Here, the inlet temperatures are identical. The volume flows through absorber 3 and condenser 5 can be varied in opposite directions by the valve position of valve 50 and the total flow can be regulated by the pump 44.

[0061] Fig. 6 shows a schematic representation of a further embodiment of the control device 36 according to the invention. As in the embodiment according to Fig. 5Cooling fluid flows through the absorber section 37 and the condenser section 38 in parallel. The cooling fluid flow through the absorber section 37 is controlled by valve 60 and pump 61, while the cooling fluid flow through the condenser section 38 is controlled by valve 62 and pump 63. In this way, not only can the cooling fluid flows be controlled separately, but the inlet temperatures into the absorber 3 and the condenser 5 can also be decoupled from each other. This allows the process of storing refrigerant in the storage device and the process of retrieving refrigerant from the storage device to be initiated more quickly.

[0062] Furthermore, the speed of refrigerant storage and retrieval can be increased. Furthermore, operating limits caused by solvent crystallization or possible refrigerant icing can be more easily maintained during operation thanks to the freedom to control the temperatures and flow rates of the cooling fluid through absorber 3 and condenser 5 completely independently. At the same time, the required safety routines for preventing crystallization or ice formation in the absorption chiller system have more options for responding to such events thanks to the decoupling.

[0063] The storage capacity depends on the amount of operating fluid (solvent and refrigerant) in the sorption system. The magnitude of the cold storage also depends on the loading and unloading concentration of the solution and the respective load case for the sorption system. In addition to manufacturer-specific safety limits, the loading concentration is physically limited by crystallization (see [Fig. Fig. 4 ). The discharge concentration depends on the design and operating point.

[0064] Using the example of three system types A1, A2, and A3 equipped with the process, with nominal outputs of 50 W, 160 W, and 500 kW, respectively, Table 1 compares the storage capacity of the corresponding sensible cold water storage tanks (Table 1, last row) with the size of the tanks. A typical solution concentration difference in kg LiBr / kg solution of 10% between loading and unloading is assumed. This shows that, with appropriate design and use of the process, a storage equivalent of 5 m3 is possible when using system A1. Tab. 1 Unit A1 A2 A3 Solution (54% LiBr in solution) [L] 55 110 240 Refrigerant / Water [L] 26 35 200 Mass of the solution [kg] 92 185 403 Mass of solvent / LiBr [kg] 50 100 218 Mass of water [kg] 68 120 385 Solution loaded (63% LiBr in solution) [kg] 79 158 346 Solution uncharged (53% LiBr in solution) [kg] 127 226 727 Difference (m H2O) [kg] 48 68 382 Energy storage capacity [kWh] 30 43 239 Cold water storage equivalent [m 3< ] 5,2 7,3 41,1

[0065] The accessible storage capacity increases linearly with the amount of operating fluid. Thus, with a corresponding increase in process fluid quantities, much higher cold water storage equivalents are possible for the same systems. List of reference symbols

[0066] 1 Absorption chiller 2 Evaporator 3 Absorber 4 Desorber 5 Condenser 6 Process fluid circuit 6a Solvent circuit 6b Pump 6c Section of process fluid circuit 6 (refrigerant circulation) 6d Pump 6e Refrigerant vapor 6f Section 7 High-temperature circuit 7a High-temperature heat source 8 Heat sink circuit / cooling fluid circuit 8a Heat sink 9 Low-temperature circuit 9a Low-temperature heat source 10 Throttle 11 Solution heat exchanger 12, 13 Housing 20, 20a Lines of equal concentration 21 Point (triple point of water) 22 Crystallization line 23, 24 Process layer lines 30 - 32 Pumps 33, 34 Valves 35 Storage tank 36 Control device 37 Absorber section 38 Condenser section 39Bypass section 40, 41Valves 42, 43Valve outlets 44Pump 50Valve 60Valve 61Pump 62Valve 63Pump

Claims

1. A method for operating a sorption system (1), the sorption system comprising the following: - a cooling fluid circuit (8) with a cooling fluid; - a process medium circuit (6) with a refrigerant and a solvent; - an absorber (3) which is connected to the cooling fluid circuit (8) and to the process medium circuit (6); - a condenser (5) which is connected to the cooling fluid circuit (8) and to the process fluid circuit (6); and - a control device (36); wherein during operation of the sorption system (1), the cooling fluid is fed to the absorber (3) and to the condenser (5), wherein by means of the control device (36), a feed of the cooling fluid to the absorber (3) and a feed of the cooling fluid to the condenser (5) are controlled differently from each other and a flow ratio for a flow of the cooling fluid through the absorber (3) and a flow of the cooling fluid through the condenser (5) is controlled, characterized in that the feed of the cooling fluid to the absorber and the feed of the cooling fluid to the condenser are controlled independently from each other.

2. The method according to claim 1, characterized in that by means of controlling the feed of the cooling fluid to the absorber (3) and the feed of the cooling fluid to the condenser (5) by the control device (36), an input temperature of the cooling fluid to the absorber (3) and an input temperature of the cooling fluid to the condenser (5) are controlled differently.

3. The method according to claim 1 or 2, characterized in that in a first state of the control device (36) compared to a basic state of the control device (36), - the feed of the cooling fluid to the absorber (3) is decreased and / or - the feed of the cooling fluid to the condenser (5) is increased.

4. The method according to claim 3, characterized in that in the first state of the control device (36), a concentration of refrigerant in a portion of a solvent circuit (6a) formed in the process medium circuit (6) and containing the solvent is decreased.

5. The method according to claim 4, characterized by a desorber (4) which is connected to the solvent circuit (6a), wherein an expulsion of the refrigerant in the desorber (4) is decreased by means of increasing the concentration of refrigerant compared to the basic state of the control device (36).

6. The method according to any one of claims 3 to 5, characterized in that when the feed of refrigerant to the condenser (5) is increased in the first state of the control device (36), the refrigerant is subsequently stored in a storage device which is connected to the process medium circuit (6).

7. The method according to any one of the preceding claims, characterized in that in a second state of the control device (36) compared to the basic state of the control device (36), - the feed of the cooling fluid to the absorber (3) is increased and / or - the feed of the cooling fluid to the condenser (5) is decreased.

8. The method according to claim 6 or 7, characterized in that in the second state of the control device (36), the refrigerant is discharged from the storage device.

9. The method according to claim 8, characterized by an evaporator (2) which is connected to the process medium circuit (6), wherein in the second state of the control device (36), the refrigerant is fed from the storage device to the evaporator (2) and heat from a low-temperature heat source (9a) is dissipated to the refrigerant via the evaporator (2).

10. The method according to claim 9, characterized in that the storage device is at least partially arranged in the evaporator (2).

11. The method according to any one of the preceding claims, characterized in that the cooling fluid in the cooling fluid circuit (8) is fed via - an absorber portion (37) to the absorber (3), and via - a condenser portion (38) to the condenser (5).

12. The method according to claim 11, characterized in that - a feed of cooling fluid to the absorber portion (37) is controlled by means of at least one first flow-regulating component (40; 60, 61) of the control device (36) and / or - a feed of cooling fluid to the condenser portion (38) is controlled by means of at least one second flow-regulating component (41; 62, 63) of the control device (36).

13. An arrangement for a sorption system (1), comprising: - a cooling fluid circuit (8) with a cooling fluid; - a process medium circuit (6) with a refrigerant and a solvent; - an absorber (3) which is connected to the cooling fluid circuit (8) and to the process medium circuit (6); and - a condenser (5) which is connected to the cooling fluid circuit (8) and to the process medium circuit (6); - a control device (36) which is configured, during operation of the sorption system (1), to control the feed of the cooling fluid to the absorber (3) and the feed of the cooling fluid to the condenser (5) differently from each other and to control a flow ratio for a flow of the cooling fluid through the absorber (3) and a flow of the cooling fluid through the condenser (5), characterized in that the control device (36) is configured to control the feed of the cooling fluid to the absorber (3) and the feed of the cooling fluid to the condenser (5) independently from each other.

14. A sorption system (1) with an arrangement according to claim 13.