Arrangement for a combined heat and power system

Abstract

Arrangement for a combined cooling and heating system with a refrigeration circuit and a heat pump circuit, which have a common evaporator-condenser (70) and are thus thermally connected to each other, wherein the refrigeration circuit also has at least one evaporator (3), a refrigeration compressor (1) and a throttle valve (5) directly connected to a liquid outlet (740) of the common evaporator-condenser (70) and the heat pump circuit also has at least one heat pump compressor (2), a condenser (4) and a heat pump throttle valve (6), the heat pump throttle valve (6) being arranged downstream of the condenser (4), the evaporator-condenser (70) having separate channels belonging to the refrigeration circuit on the one hand and to the heat pump circuit on the other, and the wall parts of the channels of the evaporator-condenser (70) having heat transfer surfaces that border the refrigeration circuit on the one hand and the heat pump circuit on the other.characterized in that, in addition to the components listed above, at least one controllable heat exchanger, a waste heat cooler (10), is arranged downstream of the refrigeration compressor (1) in the refrigeration circuit, and that, in addition to the components listed above, at least one controllable heat exchanger, an auxiliary evaporator (90) with outlet (104) and inlet (103), is arranged in the heat pump circuit, and a flow connection with an auxiliary throttle valve (61) is provided downstream of the condenser (4), which opens into the auxiliary evaporator (90), wherein the waste heat cooler (10) is connected to an external heat sink between outlet (102) and inlet (101), and the auxiliary evaporator (90) is connected to an external heat source between outlet and inlet.

Description

The invention relates to an arrangement for a cold-heat coupling with two counterclockwise cold vapor processes, the refrigeration cycle and the heat pump cycle, which are thermally connected. Examples of arrangements for combined heat and cooling are known from JP-H09-138 046 A , DE 699 31 350 T2 , US 2009 / 0 260 389 A1 and JP 2008-298 407 A. The refrigeration cycle contains at least one evaporator, in which the refrigerant evaporates by absorbing a heat flow, thereby providing the cooling capacity; a refrigeration compressor to increase the refrigerant pressure to an intermediate pressure level; and an expansion valve to reduce the refrigerant pressure to a low pressure level, resulting in liquid refrigerant and refrigerant flash vapor. The heat pump cycle contains at least one heat pump compressor to increase the refrigerant vapor pressure to a high pressure level; a condenser to transfer heat of heat from cooling and condensation to a heat transfer fluid; and a heat pump expansion valve to reduce the refrigerant pressure to an intermediate pressure level, resulting in liquid refrigerant and refrigerant flash vapor. The heat flow transferred to the heat transfer fluid is referred to here as heating capacity. The cooling capacity is the intended use of the refrigeration cycle.The heating output is the intended use of the heat pump cycle. The refrigeration circuit and the heat pump circuit are thermally connected for heat transfer from the refrigeration circuit to the heat pump circuit, either via a heat exchanger, referred to here as an evaporator-condenser, or via a vessel, referred to here as an intermediate pressure tank, so that a heat flow is transferred from the refrigeration circuit to the heat pump circuit. The intermediate pressure tank contains liquid refrigerant in its bottom section, referred to as the sump area. This refrigerant, along with flash vapor, is generated after expansion from the high-pressure level to the intermediate pressure level in the heat pump expansion valve. The heat pump expansion valve is located downstream of the condenser. The evaporator condenser is part of both the refrigeration and heat pump circuits. Within the evaporator condenser are separate channels, one carrying refrigerant for the refrigeration circuit and the other carrying refrigerant for the heat pump circuit. Heat is transferred from the walls of the evaporator condenser channels in the refrigeration circuit to the walls of the channels in the heat pump circuit, causing the refrigerant vapor in the refrigeration circuit to condense and cool, while the refrigerant in the heat pump circuit evaporates. The liquefied refrigerant from the evaporator-condenser channels, which are part of the refrigeration cycle, flows to the expansion valve of the refrigeration cycle. There, it expands to low pressure directly into the evaporator or into a low-pressure separator that communicates with the evaporator. This process produces refrigerant liquid and refrigerant flash vapor. The refrigerant liquid is evaporated by the addition of heat, thus generating the cooling capacity. The evaporated refrigerant and flash vapor are extracted by the refrigerant compressor. The required cooling capacity influences the amount of vapor extracted. The refrigerant evaporated in the channels of the evaporator-condenser, which are part of the heat pump circuit, is extracted by the heat pump compressor, compressed to high pressure, and then liquefied in the condenser by transferring heat to the heat transfer fluid. The resulting heating output depends on the refrigerant flow rate. Since this is dependent on the cooling capacity, the heating output cannot be adjusted as needed. In such a combined heat and power (CHP) system, the cooling and heating outputs are in a fixed relationship to each other. When the intermediate pressure tank is located instead of the evaporator-condenser, the heat flow inherent in the compressed gas of the refrigeration compressor is transferred directly from the gaseous refrigerant to the liquid refrigerant in the sump of the intermediate pressure tank via internal heat transfer. For this purpose, the compressed gas from the refrigeration compressor is introduced into the liquid refrigerant. The liquid refrigerant evaporates, and the introduced compressed gas from the refrigeration compressor is cooled back to a saturated vapor state. The entire vapor volume, consisting of intermediate-pressure flash vapor and desuperheating vapor, flows to the heat pump compressor in the heat pump circuit, is drawn in by the heat pump compressor, compressed to a high-pressure level, and then liquefied. Liquid refrigerant is fed from the sump area of ​​the intermediate pressure tank to the throttling valve of the refrigeration circuit and expanded directly into the evaporator or into a low-pressure separator that communicates with the evaporator. Even when an intermediate pressure tank is installed, the heating output depends on the refrigerant mass flow through the refrigeration compressor and its outlet temperature. In the described arrangement, cooling capacity and heating capacity are also in a fixed ratio to each other. Cooling capacity and heating capacity cannot therefore be adjusted independently of each other to the respective cooling and heating requirements. The described combined cooling and heating system can either adjust the cooling capacity to the cooling demand or the heating capacity to the heating demand, resulting in the other heat flow not being generated as required. If the cooling capacity is adjusted to the demand, there is either too much or too little heating capacity. Conversely, if the heating capacity is adjusted to the demand, there is either too much or too little cooling capacity. Therefore, in most cases, combined heat and power (CHP) cannot be operated economically, even though it represents an ideal combination for cooling and heating. Therefore, combined heat and power (CHP) systems often have to be implemented as bivalent systems in combination with auxiliary heating, or some of the heating output is released unused into the environment. This undesirably increases installation and / or operating costs. This makes it more difficult to apply the otherwise very effective heat-cooling technology. The object of the invention is to control both cooling capacity and heating capacity independently of each other by means of a new arrangement of a cooling-heat coupling with a refrigeration circuit and with a heat pump circuit. The arrangement of a combined heat and power system according to the invention has a refrigeration circuit and a heat pump circuit, in each of which refrigerant circulates, which changes its state of matter during circulation. In addition to the components evaporator, refrigeration compressor, evaporator condenser or intermediate pressure tank and throttle valve, the refrigeration cycle contains a controllable heat exchanger located downstream of the refrigeration compressor, which shall be referred to as a "waste heat cooler". In addition to the components heat pump compressor, condenser, heat pump throttle valve, evaporator condenser or intermediate pressure tank, the heat pump circuit contains a controllable heat exchanger, which is to be referred to as an "additional evaporator". Liquid high-pressure refrigerant from the heat pump circuit is expanded into the auxiliary evaporator via an additional throttling valve, which shall be referred to as the "additional throttling valve". In the waste heat cooler, heat from the combined heat and power (CHP) system is dissipated via an external cooling fluid. The waste heat cooler contains separate channels: one carrying the refrigeration circuit of the refrigeration system and the other carrying the external cooling fluid, such as chilled water. Heat is transferred from the walls of the waste heat cooler's channels belonging to the refrigeration circuit to the walls of the channels belonging to the external cooling fluid circuit. This heat dissipates the refrigerant vapor in the refrigeration circuit and, depending on the amount of heat dissipated, partially liquefies. Meanwhile, the external cooling fluid warms up and is then discharged. The external cooling fluid is then cooled, for example, in a cooling tower and returned to the waste heat cooler. In the cooling tower, excess heat is either dissipated to the environment or utilized at this temperature level. As a result of heat dissipation in the waste heat cooler, the heat content of the refrigerant entering the evaporator condenser decreases. For further cooling (deheating) and condensation of the refrigerant vapor in the refrigeration cycle, less vapor is produced in the ductwork belonging to the heat pump circuit. Consequently, the heating capacity decreases due to the smaller refrigerant flow through the heat pump compressor. The heating capacity can be adjusted to the heating demand by varying the amount of heat dissipated in the waste heat cooler, without changing the refrigerant mass flow through the compressor or the cooling capacity. This means that the heating capacity can be reduced independently of the cooling capacity. Only the refrigerant mass flow required for the heating capacity is compressed in the heat pump compressor. If an intermediate pressure tank is used instead of the evaporator condenser, the amount of steam that must be extracted from the intermediate pressure tank by the heat pump compressor also decreases, since some of the heat from the refrigeration cycle has been dissipated to the outside at the waste heat cooler. Even with an intermediate pressure tank, the heating capacity decreases due to the reduced refrigerant flow through the heat pump compressor, regardless of the cooling capacity. The heating capacity can be adjusted independently of the cooling capacity. If the heating output needs to be increased, the external heat dissipation at the waste heat cooler is reduced. If the heating output needs to be increased even further, the external heat dissipation at the waste heat cooler is completely interrupted, and the auxiliary evaporator is supplied with an external heating fluid, thus introducing an additional heat flow into the combined heat and power (CHP) system. The auxiliary evaporator contains separate channels, one through which the refrigerant of the heat pump circuit flows, and the other through which an external heating fluid, such as water or air, flows. The heat content of the external heating fluid can also be absorbed from previously unusable waste heat, provided its temperature allows it to be integrated into the combined heat and power (CHP) system. The heat flow from the wall sections belonging to the external heating fluid circuit is transferred to the wall sections belonging to the heat pump circuit, so that liquid refrigerant in the heat pump circuit evaporates depending on the amount of heat supplied, thus increasing the circulating refrigerant mass flow through the heat pump compressor of the heat pump circuit. In one variant, refrigerant that has been expanded in the auxiliary throttle valve is injected directly into the channels of the auxiliary evaporator and evaporates as a result of the thermal stress caused by the external heating fluid. The heat pump compressor, through its capacity control, maintains the evaporation pressure and thus the evaporation temperature in the evaporator condenser at a level that allows heat to be supplied to the refrigerant by the external heating fluid. In a second embodiment, the auxiliary evaporator is connected to the intermediate pressure tank. In another advantageous embodiment, the auxiliary evaporator is arranged in the bottom region of the intermediate pressure tank, so that heat from the external heating fluid is transferred to the refrigerant liquid, causing it to evaporate. In both variants, additional refrigerant vapor is generated, which is additionally supplied to the heat pump circuit on the suction side of the compressor, so that the mass flow rate conveyed by the compressor increases and thus also the heating output. The heating fluid used in the described arrangements can be cooling tower water, process water, cooling water from other consumers, or, in the manner of an air-to-water heat pump, even air. The temperature profiles at both the heat sink, i.e., the waste heat cooler, and the heat source, i.e., the auxiliary evaporator, determine the intermediate pressure level of the heat-cooling system. Advantageous variants for the arrangement of the additional evaporator in a combined heat and power system are proposed in the exemplary embodiments. Intermediate pressure and condensation temperature are correlated. To release heat at the waste heat cooler, the temperature must be higher than the temperature of the heat sink. To absorb heat at the auxiliary evaporator, the temperature must be lower than the temperature of the heat source. According to a feature of the invention, the intermediate pressure is regulated at the waste heat cooler for the purpose of heat dissipation, i.e., heat extraction, and heat absorption, i.e., heat coupling, at the additional evaporator. The solution according to the invention includes the fact that the same external fluid acts as both a heat sink and a heat source. The invention is explained using exemplary embodiments. Fig. 1 and Fig. 2 show known arrangements for combined cooling and heating with a refrigeration circuit and with a heat pump circuit. Fig. 3, Fig. 4, Fig. 5, Fig. 6, and Fig. 7 show arrangements according to the invention. The combined cooling and heating system according to Fig. 1 with a refrigeration cycle and a heat pump cycle, in each of which refrigerant circulates, which changes its state of matter from vaporous to liquid and from liquid to vaporous during circulation in the respective cycle. The refrigeration cycle comprises an evaporator 3, in which the refrigerant evaporates by absorbing a heat flow between ports 31 and 32, thereby generating cooling capacity; a refrigeration compressor 1 to increase the refrigerant pressure to an intermediate pressure level; and an expansion valve 5 to reduce the refrigerant pressure to a low pressure level, producing refrigerant liquid and refrigerant flash vapor. The heat pump cycle consists of a heat pump compressor 2 to increase the refrigerant vapor pressure to a high pressure level; a condenser 4 to transfer heat of heat from cooling and condensation to a heat transfer fluid; and a heat pump expansion valve 6 to reduce the refrigerant pressure to an intermediate pressure level. This pressure reduction produces refrigerant liquid and refrigerant flash vapor. The heat flow transferred to the heat transfer fluid is the heating capacity. Cooling capacity is the intended use of the refrigeration cycle. Heating capacity is the intended use of the heat pump cycle. The refrigeration circuit and the heat pump circuit are thermally connected via the evaporator-condenser 70 for heat transfer from the refrigeration circuit to the heat pump circuit, so that a heat flow is transferred from the refrigeration circuit to the heat pump circuit. For this purpose, the channel sections of the evaporator-condenser 70 belonging to the refrigeration circuit are connected on their inlet side to the pressure line 730 and on their outlet side to the liquid drain 740, while the channel sections belonging to the heat pump circuit are connected on their inlet side to the connection 710 and on their outlet side to the suction line 720. The WP throttle valve 6 is located downstream of the condenser. The evaporator-condenser 70 is part of both the refrigeration and heat pump circuits. Within the evaporator-condenser 70, separate channels are traversed by refrigerant belonging to the refrigeration circuit on one side and by refrigerant belonging to the heat pump circuit on the other. Heat is transferred from the walls of the channels belonging to the refrigeration circuit to the walls of the channels belonging to the heat pump circuit, causing the refrigerant vapor in the refrigeration circuit to be heated and condensed, while the refrigerant in the channels belonging to the heat pump circuit evaporates. The liquefied refrigerant from the channels of the evaporator-condenser 70 flows via the liquid outlet 740 to the throttle valve 5 of the refrigeration circuit, where it enters the low-pressure separator 8 at connection 81 at a low-pressure level. The low-pressure separator 8 communicates with the evaporator 3 via inlet 82. The refrigerant evaporates in the evaporator 3 due to the input of heat, thus generating the cooling capacity. Evaporated refrigerant and flash vapor are extracted by the refrigerant compressor 1 via the suction line 83. The required cooling capacity influences the amount of vapor extracted. The refrigerant evaporated in the channels of the evaporator-condenser 70 (not shown), which belong to the heat pump circuit, is drawn off by the heat pump compressor 2 via the suction line 720, compressed to high pressure, and then liquefied in the condenser 4 by transferring heat to the heat transfer fluid, which is supplied at port 41 and discharged at port 42. The resulting heating output depends on the refrigerant flow rate. Since this is dependent on the cooling output, the heating output cannot be adjusted as needed. Cooling output and heating output are in a fixed relationship to each other. The combined heat and power (CHP) system according to Fig. 2 has an intermediate pressure tank 7 instead of the evaporator-condenser 70 according to Fig. 1, in which the heat flow from the refrigeration circuit is transferred to the heat pump circuit. The intermediate pressure tank 7 contains liquid refrigerant in its bottom section, referred to as the sump section. This refrigerant, along with flash steam, is fed into the intermediate pressure tank 7 at connection 71 after expansion from the high-pressure level in the heat pump throttle valve 6 to the intermediate pressure level. In the intermediate pressure tank 7, the heat flow inherent in the pressurized gas supplied via pressure line 74 is transferred directly from the gaseous refrigerant to the liquid refrigerant in the sump area of ​​the intermediate pressure tank via internal heat transfer. For this purpose, the pressurized gas from the refrigerant compressor is introduced into the liquid refrigerant. The liquid refrigerant evaporates, and the introduced pressurized gas from the refrigerant compressor is cooled back to a saturated vapor state. The entire vapor volume, consisting of medium-pressure flash vapor and desuperheating vapor, passes to the heat pump compressor 2 in the heat pump circuit, is drawn in by the heat pump compressor 2, compressed to a high-pressure level, and then liquefied in the condenser 4. Liquid refrigerant from the sump area of ​​the intermediate pressure tank 7 is directed via the liquid outlet 72 to the throttle valve 5 of the refrigeration circuit and expanded in the low-pressure separator 8, which communicates with the evaporator 3. The mass flow rates mKA to the refrigeration compressor and mWP to the heat pump compressor depend on the cooling capacity. They are related to each other in a way that cannot be arbitrarily changed. This is the disadvantage of conventional combined refrigeration and heat pump systems. Fig. 3 shows an arrangement of a cold-heat coupling according to the invention. In addition to the components evaporator 3, refrigeration compressor 1, intermediate pressure tank 7 and throttle valve 5, the refrigeration circuit contains a controllable heat exchanger, the waste heat cooler 10, arranged downstream of the refrigeration compressor 1. In addition to the components heat pump compressor 2, condenser 4, heat pump throttle valve 6, intermediate pressure tank 7, the heat pump circuit contains a controllable heat exchanger, the auxiliary evaporator 9, which communicates with the intermediate pressure tank 7. In the waste heat cooler 10, an external cooling fluid is supplied at the inlet 101 and discharged at the outlet 102. The cooling fluid carries away heat from the combined heat and power (CHP) system to the outside. For this purpose, the waste heat cooler 10 contains separate channels (not shown) through which the refrigerant from the refrigeration system flows on one side and the external cooling fluid, for example, chilled water, on the other. The external cooling fluid enters at the inlet 101 and exits at the outlet 102. Heat is transferred from the wall sections of the channels in the waste heat cooler 10 that belong to the refrigeration circuit to the wall sections of the channels belonging to the external cooling fluid circuit. This causes the refrigerant vapor in the refrigeration circuit to cool down and, depending on the amount of heat dissipated, to partially liquefy. Meanwhile, the external cooling fluid heats up and is then discharged to the outside. The external cooling fluid is then cooled, for example, in a cooling tower and returned to the waste heat cooler.In the cooling tower, excess heat is either released into the environment or used for other purposes. The heat pump compressor 2, through its volume flow control, maintains the evaporation pressure and thus the evaporation temperature in the intermediate pressure tank 7 at a level that allows heat extraction at the waste heat cooler 10 to the external cooling fluid. As a result of the heat removal in the waste heat cooler 10, the heat content of the refrigerant entering the intermediate pressure tank 7 decreases. Less vapor is produced in the intermediate pressure tank 7 for further cooling (deheating) and condensation of the refrigerant vapor in the refrigeration cycle, since some of the heat has already been extracted at the waste heat cooler 10. The heating output is thus reduced due to the smaller refrigerant flow through the heat pump compressor 2. The heating output can be adjusted to lower heating demands by increasing or decreasing the heat dissipation in the waste heat cooler 10, without changing the refrigerant mass flow through the refrigeration compressor 1 or the cooling output. This means that the heating output can be reduced independently of the cooling output. If the heating output is to be increased, the external heat dissipation at the waste heat cooler 10 is reduced. If the heating output is to be increased even further, the external heat dissipation at the waste heat cooler 10 is interrupted. The auxiliary evaporator 9 is supplied with an external heating fluid, which enters at the inlet 91 and exits at the outlet 92, thus introducing an additional heat flow into the combined heat and power (CHP) system. The auxiliary evaporator 9 contains separate channels (not shown) through which the refrigerant of the heat pump circuit flows on one side and the external heating fluid, for example water or air, flows on the other. The channels belonging to the heat pump circuit communicate with the intermediate pressure tank 7 via pipes. The refrigerant circulation pump is not shown. The heat content of the external heating fluid can also be extracted from waste heat or from the environment if the temperature allows coupling into the heat-cooling system. The heat flow from the wall sections belonging to the external heating fluid circuit of the auxiliary evaporator 9 is supplied to the wall sections belonging to the heat pump circuit, causing liquid refrigerant in the heat pump circuit to evaporate depending on the amount of heat supplied. This increases the refrigerant mass flow rate that reaches the heat pump compressor 2 via the suction line 73. It is compressed to a high-pressure level and then liquefied in the condenser 4, thus increasing the usable heating capacity between connections 41 and 42. The heat pump compressor 2, through its volume flow control, maintains the evaporation pressure and thus the evaporation temperature in the intermediate pressure tank 7 at a level that allows heat input in the auxiliary evaporator 9 from the external heating fluid to the refrigerant. Liquid refrigerant from the sump area of ​​the intermediate pressure tank 7 is depressurized at the liquid outlet 72 on the throttle valve 5 and fed via connection 81 into the low-pressure separator 8, which communicates with the evaporator 3 via inlet 82. The cooling between connections 31 and 32 is adjustable, as the delivery volume of the refrigeration compressor 1, which is connected to the low-pressure separator 8 via the suction line 83, can be adapted to the demand. The cooling capacity can therefore be adjusted to the demand independently of the heating capacity requirement. Fig. 4 relates to an arrangement according to the invention in which the refrigeration circuit and the heat pump circuit are thermally connected to each other for heat transfer from the refrigeration circuit to the heat pump circuit via the evaporator-condenser 70, so that a heat flow is transferred from the refrigeration circuit to the heat pump circuit. For this purpose, as already explained with reference to Fig. 1, the channel sections of the evaporator-condenser 70 belonging to the refrigeration circuit are connected on their inlet side to the pressure line 730 and on their outlet side to the liquid drain 740, while the channel sections belonging to the heat pump circuit are connected on their inlet side to the connection 710 and on their outlet side to the connection 720. Liquid refrigerant is injected directly into the evaporator-condenser 70 via the heat pump throttle valve 4 from an unspecified collection tank located downstream of the condenser 4. The refrigerant evaporates in the duct sections belonging to the heat pump circuit. The injection quantity is controlled by known means, for example, by thermostatic or electronic injection valves that regulate the superheating of the refrigerant vapor at the outlet of the evaporator-condenser 70. After leaving the evaporator-condenser 70, the refrigerant vapor is extracted via the suction line of the heat pump compressor. The waste heat cooler 10 is located in the pressure line 730. The details of the function of the waste heat cooler 10 were explained in the description for Fig. 3. In the waste heat cooler 10, an external cooling fluid is supplied at the inlet 101 and discharged at the outlet 102. The cooling fluid carries away a heat flow from the combined heat and power (CHP) system to the outside. As a result of the heat removal in the waste heat cooler 10, the heat content of the refrigerant entering the evaporator condenser 70 decreases. Less vapor is produced in the evaporator condenser 70 for further cooling (deheating) and condensation of the refrigerant vapor in the refrigeration cycle, since some of the heat has already been extracted at the waste heat cooler 10. The heating output is thus reduced due to the smaller refrigerant flow through the heat pump compressor 2. The heating output can be adjusted to lower heating demands by increasing or decreasing the heat dissipation in the waste heat cooler 10, without changing the refrigerant mass flow through the refrigeration compressor 1 or the cooling output. This means that the heating output can be reduced independently of the cooling output. If the heating output is to be increased, the external heat dissipation at the waste heat cooler 10 is reduced. If the heating output is to be increased even further, the external heat dissipation at the waste heat cooler 10 is interrupted. The auxiliary evaporator 90 is now supplied with an external heating fluid, which enters at the inlet 103 and exits at the outlet 104, so that an additional heat flow is introduced into the heat pump circuit. The auxiliary evaporator 90 contains separate channels (not shown) through which the refrigerant of the heat pump circuit flows on one side and the external heating fluid flows on the other between inlet 103 and outlet 104. Liquid refrigerant is injected directly into the auxiliary evaporator 90 via the auxiliary throttle valve 61 from an unspecified collection tank located downstream of the condenser 4. The refrigerant evaporates in the duct sections belonging to the heat pump circuit. The injection quantity is controlled by known means, such as thermostatic or electronic injection valves, which regulate the superheating of the refrigerant vapor at the outlet of the auxiliary evaporator 90. After leaving the auxiliary evaporator 90, the refrigerant vapor is fed into the suction line of the heat pump compressor, increasing the mass flow rate through the compressor. It is then compressed to a high-pressure level and subsequently liquefied in the condenser 4, thus increasing the heating capacity between connections 41 and 42. The heat pump compressor 2, through its volume flow control, maintains the evaporation pressure and thus the evaporation temperature in the evaporator condenser 70 at a level that allows heat input in the auxiliary evaporator 90 from the external heating fluid to the refrigerant. The heat content of the external heating fluid can also be extracted from waste heat or from the environment if the temperature allows coupling into the heat-cooling system. Fig. 5 relates to an advantageous embodiment according to the invention with an intermediate pressure tank 700 in which the auxiliary evaporator 920 is arranged in the sump section of the intermediate pressure tank 700. The auxiliary evaporator 920 is surrounded by liquid refrigerant. Channels are provided in the auxiliary evaporator 920 through which the external heating fluid flows between inlet 911 and outlet 921, so that an additional vapor volume is generated depending on the supplied external heat flow. The additional vapor volume is drawn off via the suction line 703 together with the vapor from the refrigeration cycle resulting from deheating and condensation in the intermediate pressure tank 700 and compressed to a high-pressure level. It is then liquefied in the condenser 4, so that the heating capacity between the connections 41 and 42 increases. The additional steam volume thus increases the heating output of the heat pump. The heat pump compressor 2, through its volume flow control, maintains the evaporation pressure and thus the evaporation temperature in the intermediate pressure tank 700 at a level that allows heat input in the auxiliary evaporator 920 from the external heating fluid to the refrigerant. The remaining components of the arrangement in Fig. 5 are assigned as described in Fig. 3. In the waste heat cooler 10, an external cooling fluid is supplied at the inlet 101 and discharged at the outlet 102 as described in Fig. 3, so that the heating power can be reduced as a result of heat extraction from the combined cooling and heating process. The compact design of the arrangement of the additional evaporator 920 in the intermediate pressure tank 700 is advantageous. Fig. 6 describes an arrangement according to the invention. In addition to the arrangement according to Fig. 3, an economizer intermediate pressure tank 96 is provided which communicates with an additional evaporator 95. The Economizer intermediate pressure tank 96 has a steam space in the upper area, which is connected to an intermediate pressure opening of the heat pump compressor 2. The economizer intermediate pressure tank 96 has a sump in its lower section containing refrigerant liquid. To discharge liquid refrigerant, the economizer intermediate pressure tank 96 communicates with the heat pump throttle valve 6, which in this case is a high-pressure float valve. Downstream of the heat pump throttle valve 6, the expanded refrigerant flows into the intermediate pressure tank 7. The pressure at the intermediate pressure port of the heat pump compressor 2 is higher than the pressure in the intermediate pressure tank 7, so that the evaporation temperature in the economizer intermediate pressure tank 96 is higher than the evaporation temperature in the intermediate pressure tank 7. This arrangement is therefore advantageous when external heating fluids with different temperature levels are available: a lower temperature for the auxiliary evaporator 9 at inlet 91 and a higher temperature for the auxiliary evaporator 95 at inlet 93, so that the heat flows from the external heating fluids are fed into the combined heat and power (CHP) system as additional heat flows at the highest possible temperature. This increases the efficiency of heat generation for heating. Fig. 7 describes an arrangement according to the invention. In addition to the arrangement according to Fig. 4, an additional evaporator 99 is arranged. Liquid refrigerant is injected directly into the auxiliary evaporator 99 via the heat pump throttle valve 4 from an unspecified collection tank located downstream of the condenser 4. The refrigerant evaporates in the duct sections belonging to the heat pump circuit. The injection quantity is controlled by known means, for example, by thermostatic or electronic injection valves that regulate the superheating of the refrigerant vapor at the outlet of the auxiliary evaporator 99. The refrigerant-side port of the auxiliary evaporator 99 is connected to an intermediate pressure port of the heat pump compressor 2. The pressure at the intermediate pressure port of the heat pump compressor 2 is higher than the pressure in the suction line 720, so that the evaporation temperature in the auxiliary evaporator 99 is higher than the evaporation temperature in the evaporator-condenser 70. This arrangement is advantageous when external heating fluids with different temperature levels are available: a lower temperature for the auxiliary evaporator 90 at the inlet 91 and a higher temperature for the auxiliary evaporator 95 at the inlet 93, so that the heat flows from the external heating fluids are fed into the combined heat and power (CHP) system as additional heat flows at the highest possible temperature. This increases the efficiency of heat generation for heating. The described arrangements according to the invention allow the heating output to be controlled independently of the cooling output under changing operating conditions. List of reference symbols used 1 Refrigeration compressor 2 Heat pump compressor 3 Evaporator 4 Condenser 5 Expansion valve 6 Heat pump expansion valve 7 Intermediate pressure tank 8 Low-pressure separator 9 Auxiliary evaporator 10 Waste heat cooler 31 Connection 32 Connection 41 Connection 42 Connection 61 Auxiliary expansion valve 62 Auxiliary expansion valve 63 Auxiliary expansion valve 70 Evaporator-condenser 71 Connection 72 Liquid drain 73 Suction line 74 Pressure line 81 Connection 82 Inlet 83 Suction line 90 Auxiliary evaporator 91 Inlet 92 Outlet 93 Inlet 94 Outlet 95 Auxiliary evaporator 96 Economizer-intermediate pressure tank 97 Inlet 98 Outlet 99 Auxiliary evaporator 101 Inlet 102 Outlet 103 Inlet 104 Outlet 700 Intermediate pressure tank 703 Suction line 710 Connection 720 Suction line 730 Pressure line 740 Liquid outlet 911 Inlet 920 Auxiliary evaporator 921 Outlet

Claims

Arrangement for a combined cooling and heating system with a refrigeration circuit and a heat pump circuit, which have a common evaporator-condenser (70) and are thus thermally connected to each other, wherein the refrigeration circuit also has at least one evaporator (3), a refrigeration compressor (1) and a throttle valve (5) directly connected to a liquid outlet (740) of the common evaporator-condenser (70) and the heat pump circuit also has at least one heat pump compressor (2), a condenser (4) and a heat pump throttle valve (6), the heat pump throttle valve (6) being arranged downstream of the condenser (4), the evaporator-condenser (70) having separate channels belonging to the refrigeration circuit on the one hand and to the heat pump circuit on the other, and the wall parts of the channels of the evaporator-condenser (70) having heat transfer surfaces that border the refrigeration circuit on the one hand and the heat pump circuit on the other.characterized in that, in addition to the components listed above, at least one controllable heat exchanger, a waste heat cooler (10), is arranged downstream of the refrigeration compressor (1) in the refrigeration circuit, and that, in addition to the components listed above, at least one controllable heat exchanger, an auxiliary evaporator (90) with outlet (104) and inlet (103), is arranged in the heat pump circuit, and a flow connection with an auxiliary throttle valve (61) is provided downstream of the condenser (4), which opens into the auxiliary evaporator (90), wherein the waste heat cooler (10) is connected to an external heat sink between outlet (102) and inlet (101), and the auxiliary evaporator (90) is connected to an external heat source between outlet and inlet. Arrangement for a combined cooling and heating system with a refrigeration circuit and a heat pump circuit, which have a common intermediate pressure tank (7, 700) and are thereby thermally connected to each other, wherein the refrigeration circuit also has at least one evaporator (3), one refrigeration compressor (1) and a throttle valve (5) and the heat pump circuit also has at least one heat pump compressor (2), one condenser (4) and a heat pump throttle valve (6), the intermediate pressure tank (7, 700) has a sump area in its bottom region in which liquid refrigerant is located, the heat pump throttle valve (6) is arranged downstream of the condenser (4), characterized in that, in addition to the components listed above, the refrigeration circuit includes at least one controllable heat exchanger, a waste heat cooler (10),is arranged downstream of the refrigeration compressor (1) and that, in addition to the components listed above, the heat pump circuit includes at least one controllable heat exchanger, an auxiliary evaporator (9, 920) with outlet (92, 921) and inlet (91, 911), which is communicatively connected to the intermediate pressure tank (7, 700), wherein the waste heat cooler (10) between outlet (102) and inlet (101) is connected to an external heat sink and the auxiliary evaporator (9, 920) between outlet (92, 921) and inlet (91, 911) is connected to an external heat source. Arrangement for a combined cooling and heating system with a refrigeration cycle and with a heat pump cycle according to claim 2, characterized in that the auxiliary evaporator and the intermediate pressure tank form a single unit, wherein the auxiliary evaporator (920) is arranged in the intermediate pressure tank (700), and the auxiliary evaporator (920) is connected to an external heat source between the outlet (921) and the inlet (911). Arrangement for a combined cooling and heating system with a refrigeration circuit and with a heat pump circuit according to claim 2, characterized in that a further additional evaporator (95) is provided, which has a flow connection downstream of the condenser (4) with an additional throttle valve (62), which is communicatively connected to an economizer intermediate pressure tank (96), which is connected in the head region to an intermediate pressure connection on the heat pump compressor (2) and which is connected in the sump region to the intermediate pressure tank (7) via the WP throttle valve (6), wherein the additional evaporator (95) is connected to an external heat source between the outlet (94) and the inlet (93). Arrangement for a combined cooling and heating system with a refrigeration circuit and with a heat pump circuit according to claim 1, characterized in that a further additional evaporator (99) is provided, which has a flow connection with an additional throttle valve (63) on the inlet side downstream of the condenser (4) and is connected on the outlet side to an intermediate pressure connection on the heat pump compressor (2).

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