CN111550951B

CN111550951B - Absorption heat pump system and adjusting method

Info

Publication number: CN111550951B
Application number: CN202010433266.0A
Authority: CN
Inventors: 刘锋; 井洋; 隋军; 刘泰秀; 金红光
Original assignee: Institute of Engineering Thermophysics of CAS
Current assignee: Institute of Engineering Thermophysics of CAS
Priority date: 2020-05-20
Filing date: 2020-05-20
Publication date: 2022-02-18
Anticipated expiration: 2040-05-20
Also published as: CN111550951A

Abstract

An absorption heat pump system comprising: an absorber (111), a generator (112), a condenser (114), an evaporator (113), a refrigerant pump (122), a first conditioning unit (130), and a second conditioning unit (140), wherein: an absorber (111) for absorbing refrigerant vapor to release heat from the high concentration solution and generating a low concentration solution; a generator (112) for the low concentration solution to absorb heat to release refrigerant and generate a high concentration solution; a condenser (114) for condensing the refrigerant released from the generator (112); an evaporator (113) for evaporating the refrigerant condensed by the condenser (114) to form a refrigerant vapor; a first adjusting unit (130) for storing the low concentration solution and adjusting the amount of the low concentration solution in the absorber (111); a second regulating unit (140) for storing the high concentration solution and regulating the amount of the high concentration solution in the generator (112); a refrigerant pump (122) is provided between the evaporator (113) and the condenser (114).

Description

Absorption heat pump system and adjusting method

Technical Field

The disclosure relates to the technical field of absorption heat pumps, in particular to an absorption heat pump system and an adjusting method.

Background

With the improvement of the living standard of people in China, the industrialization degree and the urbanization degree are rapidly improved, but the energy environmental problem is increasingly prominent. Energy consumption of five industries of chemical industry, cement, other building material kilns, non-ferrous metal smelting and steel in the industry accounts for about 70 percent of total industrial energy consumption, the heat efficiency of the five industries is only 20-60 percent generally, and a large amount of residual heat and waste heat at 40-100 ℃ are discharged into the environment in the forms of waste gas, waste water and the like. Statistically, about 50% of the energy input to the manufacturing industry is wasted in the form of heat. With the development of urbanization and industrialization, the heat demand and the cold demand in residents and industrial processes are greatly improved, the part of load is mainly solved through a coal-fired boiler, a gas-fired boiler, a thermal power plant, electric compression refrigeration and other forms, and a large amount of high-quality coal and natural gas are consumed. The utilization of the absorption heat pump for supplying heat with the discharged waste heat or the optimization of the industrial process is an effective way for realizing waste heat utilization and energy cascade utilization. In the process of starting and stopping, variable working conditions, system internal fluctuation (in a heat pump system) and system external fluctuation (on a heat source side and a load side) of a conventional absorption heat pump, the response speed of the heat pump system for stabilizing fluctuation and the energy efficiency coefficient of a unit can be influenced by different solution reserves. In the process of starting and stopping and variable working condition operation of the absorption heat pump system, the more the system liquid storage amount is, the lower the energy efficiency coefficient is, and the longer the system response time is; and when fluctuation exists in the inside and outside of the system, the more the system liquid storage capacity is, the higher the energy efficiency coefficient is, and the better the system stability is. In the whole operation period of the existing absorption heat pump system, due to the reasons, the energy efficiency ratio slips, the response time is prolonged, the quick regulation and control are difficult to realize well, and the supply and demand matching between the system and a user is not facilitated; when the internal and external of the system fluctuate, the stability is poor, the energy utilization rate is low, and the regulation response time is long.

Disclosure of Invention

Technical problem to be solved

The present disclosure provides an absorption heat pump system and an adjustment method, which at least solve the above technical problems.

(II) technical scheme

In one aspect, the present disclosure provides an absorption heat pump system comprising: an absorber 111, a generator 112, a condenser 114, an evaporator 113, a refrigerant pump 122, a first conditioning unit 130, and a second conditioning unit 140, wherein: an absorber 111 for absorbing refrigerant vapor to release heat and generating a low concentration solution; a generator 112 for the low concentration solution to absorb heat to release refrigerant and generate a high concentration solution; the absorber 111 and the generator 112 form a circulation loop through a first pipeline and a second pipeline; a condenser 114 for condensing the refrigerant released from the generator 112; an evaporator 113 for evaporating the refrigerant condensed by the condenser 114 to form a refrigerant vapor; a first adjusting unit 130 connected to the absorber 111 for storing the low concentration solution and adjusting the amount of the low concentration solution in the absorber 111; a second adjusting unit 140 connected to the generator 112 for storing the high concentration solution and adjusting the amount of the high concentration solution in the generator 112; a refrigerant pump 122 is provided between the evaporator 113 and the condenser 114 for delivering refrigerant to the evaporator 113.

Optionally, the absorption heat pump system further comprises a solution heat exchanger 115, and the first pipeline and the second pipeline exchange heat through the solution heat exchanger 115.

Optionally, each of the first adjusting unit 130 and the second adjusting unit 140 at least includes a plurality of stop valves, an auxiliary solution pump and a liquid storage tank, and the generator 112 and the absorber 111 are connected to the

liquid storage tanks

141, 131 through the stop valve 144,134 respectively and form a circulation loop with the

liquid storage tanks

141, 131.

Optionally, the first adjusting unit 130 includes: the absorber 111, the second stop valve 134, the first liquid storage tank 131, the third stop valve 135, the fourth stop valve 136, the first liquid storage tank 131 and the first auxiliary solution pump 132 sequentially form a circulation loop, the first stop valve 133 is arranged on the first pipeline, and the fourth stop valve 136 is bridged at one end of the third stop valve 135 and one end of the first stop valve 133.

Optionally, the second adjusting unit 140 includes: a fifth stop valve 143, a sixth stop valve 144, a seventh stop valve 145, an eighth stop valve 146, a second reservoir 141, and a second auxiliary solution pump 142, wherein the generator 112, the sixth stop valve 144, the second reservoir 141, the seventh stop valve 145, and the second auxiliary solution pump 142 sequentially form a circulation loop, the fifth stop valve 143 is disposed on the second pipeline, and the eighth stop valve 146 is bridged at one end of the fifth stop valve 143 and one end of the seventh stop valve 145.

Optionally, the first pipeline further comprises a solution pump 121.

Optionally, the second pipeline further comprises a solution throttle valve 123 disposed between the second conditioning unit 140 and the absorber 111.

On the other hand, the present disclosure also provides a method for adjusting the absorption heat pump system, including:

before starting or changing load:

opening the second and sixth shut-off

valves

134 and 144 to direct most of the solution in the absorber 111 and generator 112 to the first and

second storage tanks

131 and 141;

at the time of starting or changing the load:

opening the first stop valve 133, the first auxiliary solution pump 132, the third stop valve 135, the fifth stop valve 143, the seventh stop valve 145, and the second auxiliary solution pump 142; opening the solution throttle valve 123, the solution pump 121 and the refrigerant pump 122 to inject the solution in the first and

second tanks

131 and 141 into the cycle; opening the second and

sixth cutoff valves

134 and 144 and closing the first and second

auxiliary solution pumps

132 and 142 to allow the first and

second storage tanks

131 and 141 to store a part of the solution; opening the fourth and

eighth stop valves

136 and 146 and closing the first and

fifth stop valves

133 and 143;

after the system enters a normal operation state, the second stop valve 134 and the sixth stop valve 144 are closed.

Alternatively, before starting or varying the load, if the amount of the solution in the absorber 111 or the generator 112 is less than the first preset value, the third and seventh cut-off

valves

135 and 145 are opened, and the first and second

auxiliary solution pumps

132 and 142 are started, so that the amount of the solution in the absorber 111 or the generator 112 is greater than or equal to the first preset value.

Alternatively, if the amount of the solution in the first storage tank 131 is less than the second preset value, the second stop valve 134 is opened to introduce the solution in the absorber 111 into the first storage tank 131; if the amount of the solution in the second storage tank 141 is less than the third preset value, the sixth stop valve 144 is opened to guide the solution in the generator 112 into the second storage tank 141.

(III) advantageous effects

The present disclosure provides an absorption heat pump system and an adjusting method, wherein most solution can be introduced into a liquid storage tank before starting and changing load, a small amount of solution stored in a generator and an absorber is used for starting or changing load, and when equipment is stable, the solution in the liquid storage tank is slowly introduced into circulation; when equipment fluctuates, the liquid storage capacity of the solution tank, the generator and the absorber is utilized to separate the generation process from the absorption process, so that the influence of the fluctuation on the equipment can be effectively counteracted.

Drawings

Figure 1 schematically illustrates an absorption heat pump system according to an embodiment of the present disclosure.

Detailed Description

An absorption heat pump system comprising: an absorber 111, a generator 112, a condenser 114, an evaporator 113, a refrigerant pump 122, a first conditioning unit 130, and a second conditioning unit 140, wherein: an absorber 111 for absorbing refrigerant vapor to release heat and generating a low concentration solution; a generator 112 for the low concentration solution to absorb heat to release refrigerant and generate a high concentration solution; the absorber 111 and the generator 112 form a circulation loop through a first pipeline and a second pipeline; a condenser 114 for condensing the refrigerant released from the generator 112; an evaporator 113 for evaporating the refrigerant condensed by the condenser 114 to form a refrigerant vapor; a first adjusting unit 130 connected to the absorber 111 for storing the low concentration solution and adjusting the amount of the low concentration solution in the absorber 111; a second adjusting unit 140 connected to the generator 112 for storing the high concentration solution and adjusting the amount of the high concentration solution in the generator 112; a refrigerant pump 122 is provided between the evaporator 113 and the condenser 114 for delivering refrigerant to the evaporator 113.

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to specific embodiments and the accompanying drawings.

The flow of the conventional absorption heat pump system is briefly described as follows: the concentrated solution in the absorber 111 absorbs the refrigerant vapor from the evaporator 113 to become a low concentration solution and emits heat, transferring the low concentration solution to the generator 112; the low concentration solution absorbs heat in the generator 112 to evaporate the refrigerant into a concentrated solution; the condenser 114 condenses the refrigerant evaporated by the generator 112, and emits heat; the evaporator 113 absorbs heat to evaporate the refrigerant from the condenser 114 to produce a refrigerant vapor for use by the absorber 111. The solution heat exchanger 115 recovers solution heat between the generator 112 and the absorber 111. Because partial solution storage exists in the generator and the absorber, the dynamic characteristic of the absorption heat pump system is influenced, the stable time of the starting and load changing processes is longer, and the energy efficiency coefficient is reduced when the system fluctuates. Therefore, the embodiment of the disclosure improves the system, so that the absorption heat pump system is more stable and rapid in the starting and load changing processes, and has higher energy utilization rate even when the system fluctuates.

As shown in fig. 1, an absorption heat pump system according to an embodiment of the present disclosure adds a first adjusting unit 130 and a second adjusting unit 140, where the first adjusting unit 130 is connected to the absorber 111 and is used for adjusting the amount of the low-concentration solution in the absorber 111; and a second adjusting unit 140 connected to the generator 112 for adjusting the high concentration solution in the generator 112.

The first adjusting unit 130 at least includes a plurality of stop valves, an auxiliary solution pump and a liquid storage tank, the absorber 111 is connected with the liquid storage tank 131 through a stop valve 134, and the absorber 111 and the liquid storage tank 131 are on a circulation loop. Similarly, the second adjusting unit 140 at least includes a plurality of stop valves, an auxiliary solution pump and a liquid storage tank, the generator 112 is connected to the liquid storage tank 141 through the stop valve 144, and the generator 112 and the liquid storage tank 141 are on a circulation loop.

As shown in fig. 1, in the embodiment of the present disclosure, the first adjusting unit 130 may include four cut-off valves (i.e., a first cut-off valve 133, a second cut-off valve 134, a third cut-off valve 135, and a fourth cut-off valve 136), a first liquid storage tank 131, and a first auxiliary solution pump 132. The absorber 111, the second stop valve 134, the first liquid storage tank 131, the third stop valve 135 and the first auxiliary solution pump 132 are connected in sequence to form a circulation loop, the first stop valve 133 is disposed on the first pipeline, and the fourth stop valve 136 is bridged at one end of the third stop valve 135 and one end of the first stop valve 133. Preferably, one end of the fourth cut-off valve 136 is provided between the third cut-off valve 135 and the first auxiliary solution pump 132.

The second adjusting unit 140 may include four stop valves (i.e., a fifth stop valve 143, a sixth stop valve 144, a seventh stop valve 145, and an eighth stop valve 146), a second liquid storage tank 141, and a second auxiliary solution pump 142, wherein the generator 112, the sixth stop valve 144, the second liquid storage tank 141, the seventh stop valve 145, and the second auxiliary solution pump 142 sequentially form a circulation loop, the fifth stop valve 143 is disposed on the second pipeline, and the eighth stop valve 146 is connected across one end of the fifth stop valve 143 and one end of the seventh stop valve 145. Preferably, one end of the eighth stop valve 146 is provided between the seventh stop valve 145 and the second auxiliary solution pump 142.

The absorber 111, the second stop valve 134 and the first storage tank 131 are connected, and the generator 112, the sixth stop valve 144 and the second storage tank 141 are connected to form a solution storage pipeline before starting and load changing.

The absorption heat pump system further comprises a solution heat exchanger 115, and the first pipeline and the second pipeline can exchange heat through the solution heat exchanger 115. The first line also includes a solution pump 121 and the second line also includes a solution throttle valve 123. A refrigerant pump 122 is also included between the condenser 114 and the evaporator 113. The absorber 111, the first stop valve 133, and the solution throttle valve 123 are connected, and the generator 112, the fifth stop valve 143, and the solution pump 121 are connected to form a main solution line at start-up and variable load. The first liquid storage tank 131, the third stop valve 135, the first auxiliary solution pump 132 and the absorber 111 are connected, and the second liquid storage tank 141, the seventh stop valve 145, the second auxiliary solution pump 142 and the generator are connected to form a starting and variable-load liquid injection pipeline. The first liquid storage tank 131, the third stop valve 135, the fourth stop valve 136 and the solution throttle valve 123 are connected, and the second liquid storage tank 141, the seventh stop valve 145, the eighth stop valve 146 and the solution pump 121 are connected to form a pipeline resisting fluctuation. The absorber 111, the second stop valve 134 and the first storage tank 131 are connected, and the generator 112, the sixth stop valve 144 and the second storage tank 141 are connected to form a liquid supplementing pipeline for resisting the insufficient solution of the storage tanks during the fluctuation.

On the other hand, the embodiment of the present disclosure further provides an adjusting method based on the absorption heat pump system, as follows.

Before starting or changing load:

the second and sixth shut-off

valves

134 and 144 are opened to allow most of the solution in the absorber 111 and the generator 112 to be directed to the first and

second storage tanks

131 and 141. Before starting or changing the load, if the amount of the solution in the absorber 111 or the generator 112 is less than the first preset value, the third and seventh cut-off

valves

135 and 145 are opened, and the first and second

auxiliary solution pumps

132 and 142 are started, so that the amount of the solution in the absorber 111 or the generator 112 is greater than or equal to the first preset value. If the amount of the solution in the first storage tank 131 is less than the second preset value, the second stop valve 134 is opened to guide the solution in the absorber 111 into the first storage tank 131; if the amount of the solution in the second storage tank 141 is less than the third preset value, the sixth stop valve 144 is opened to guide the solution in the generator 112 into the second storage tank 141.

For example, before starting or changing the load, the states of the solution pump 121, the refrigerant pump 122 and the solution throttle valve 123 are kept unchanged, the second stop valve 134 and the sixth stop valve 144 are opened, most of the solution in the absorber 111 and the generator 112 is respectively led into the first storage tank 131 and the second storage tank 141, and only a small part of the solution is reserved. If the amount of solution in the absorber 111 or the generator 112 is too small, the third and

seventh stop valves

135 and 145 need to be opened to start the first and second

auxiliary solution pumps

132 and 142 to replenish the solution, respectively.

At the time of starting or changing the load:

opening the first stop valve 133, the first auxiliary solution pump 132, the third stop valve 135, the fifth stop valve 143, the seventh stop valve 145, and the second auxiliary solution pump 142;

opening the solution throttle valve 123, the solution pump 121 and the refrigerant pump 122 to inject the solution in the first and

second tanks

131 and 141 into the cycle;

opening the second and

sixth cutoff valves

134 and 144 and closing the first and second auxiliary solution pumps 132 and 142 to allow the first and

second storage tanks

131 and 141 to store a part of the solution;

the fourth and

eighth stop valves

136 and 146 are opened, and the first and

fifth stop valves

133 and 143 are closed.

For example, at the time of starting or changing the load, the first stop valve 133, the third stop valve 135, the first auxiliary solution pump 132, the fifth stop valve 143, the seventh stop valve 145, and the low-pressure solution pump 142 are opened, and the other stop valves are closed, so that the solution throttle valve 123, the solution pump 121, and the refrigerant pump 122 are opened, and the solution in the first reservoir 131 and the second reservoir 141 is gradually injected into the cycle. When the solutions in the first reservoir 131 and the low-pressure reservoir 141 are completely injected into the cycle, the second stop valve 134 and the sixth stop valve 144 are opened, and the first auxiliary solution pump 132 and the second auxiliary solution pump 142 are closed. After the first liquid storage tank 131 and the second liquid storage tank 141 have the proper amount of the solution, the fourth stop valve 136 and the eighth stop valve 146 are opened, the first stop valve 133 and the fifth stop valve 143 are closed, and the system enters a normal operation state.

After the system enters a normal operation state, the second stop valve 134 and the sixth stop valve 144 are closed. When the solution amount in the first liquid storage tank 131 and the second liquid storage tank 141 is insufficient, the second stop valve 134 and the sixth stop valve 144 are opened, and the solution in the absorber 111 and the solution in the generator 112 are all led into the first liquid storage tank 131 and the second liquid storage tank 141, so that the circulation operation can realize the effects of resisting partial fluctuation influence and increasing the energy efficiency ratio of the system.

According to the absorption heat pump system, in the starting and load changing processes, the more the equipment liquid storage amount is, the longer the required stabilization time is; when the external or internal operating conditions fluctuate, the smaller the amount of the equipment liquid storage, the more the influence of fluctuation is, and the lower the operating energy efficiency coefficient is. Therefore, in the embodiment of the disclosure, most solution is introduced into the liquid storage tank before starting and changing load, and is started or changed load by a small amount of solution stored in the generator and the absorber, and when the equipment is stable, the solution in the liquid storage tank is slowly introduced into the circulation; when equipment fluctuates, the liquid storage capacity of the solution tank, the generator and the absorber is utilized to separate the generation process from the absorption process, so that the influence of the fluctuation on the equipment can be effectively counteracted.

The following takes a vertical falling film absorption heat pump with an absorber rated output heat of 25kW as an example to verify the practical application effect in the disclosure. The practical effect of the disclosure is evaluated by comprehensively considering two indexes of the time required by temperature and heat stability and the total energy efficiency coefficient of the system in two hours. Referring to table 1, during start-up, the present disclosure achieves a decrease in settling time from 840s to 480s, and a total system COP increases from 0.4902 to 0.4934 over two hours. The load change process is from 100% load to 60% load, the stability time is reduced from original 200s to 155s, and the total COP of the system is increased from 0.5089 to 0.5104 in two hours. In resisting the fluctuation of the heat source, the fluctuation caused by the flow of the heat source is basically eliminated, and the COP is increased from 0.5047 to 0.5079. In conclusion, the time required by the equipment for stabilizing time can be reduced and the energy efficiency ratio of the equipment can be slightly improved in the starting and load changing processes.

TABLE 1

It should be noted that the throttle valve in the embodiment of the present disclosure is a device for achieving pressure isolation, and other pressure isolating devices such as a U-shaped pipe and a pump may be used instead; the stop valve is a device for cutting off a pipeline and can be realized by replacing a blocking device such as a gate valve, a ball valve and the like; the embodiment describes the improvement of the flow and the regulation method of an absorber and a generator, and the similar improvement of a liquid storage device of an evaporator and a condenser can also be realized similarly; the embodiment describes a single-effect absorption refrigerator, and similar improvement of a liquid storage device aiming at a multi-effect and multi-stage absorption refrigerator can be realized similarly. The present disclosure is equally applicable to absorption heat pumps of the first type. The foregoing is a simplified description for the convenience of describing the disclosure and is not intended to indicate or imply that the referenced devices or elements must be selected and, therefore, should not be taken to be limiting of the invention. Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated.

It should also be noted that directional terms, such as "upper", "lower", "front", "rear", "left", "right", etc., mentioned in the embodiments are only directions referring to the drawings, and are not intended to limit the scope of the present disclosure. Throughout the drawings, like elements are represented by like or similar reference numerals. Conventional structures or constructions will be omitted when they may obscure the understanding of the present disclosure. And the shapes, sizes and positional relationships of the components in the drawings do not reflect the actual sizes, proportions and actual positional relationships.

Similarly, in the above description of exemplary embodiments of the disclosure, various features of the disclosure are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various disclosed aspects. Reference to the description of the terms "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the disclosure. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The above-mentioned embodiments are intended to illustrate the objects, aspects and advantages of the present disclosure in further detail, and it should be understood that the above-mentioned embodiments are only illustrative of the present disclosure and are not intended to limit the present disclosure, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present disclosure should be included in the scope of the present disclosure.

Claims

1. An absorption heat pump system comprising: an absorber (111), a generator (112), a condenser (114), an evaporator (113), a refrigerant pump (122), a first conditioning unit (130), and a second conditioning unit (140), wherein:

the absorber (111) is used for absorbing refrigerant vapor to release heat by the high-concentration solution and generating low-concentration solution;

the generator (112) is used for absorbing heat to release refrigerant and generating high-concentration solution; the absorber (111) and the generator (112) form a circulation loop through a first pipeline and a second pipeline;

the condenser (114) is used for condensing the refrigerant released by the generator (112);

the evaporator (113) is used for evaporating the refrigerant condensed by the condenser (114) to form the refrigerant vapor;

a first adjusting unit (130) connected to the absorber (111) for storing a low concentration solution and adjusting the amount of the low concentration solution in the absorber (111);

a second regulating unit (140) connected to the generator (112) for storing a high concentration solution and regulating the amount of the high concentration solution in the generator (112);

the refrigerant pump (122) is arranged between the evaporator (113) and the condenser (114) and used for conveying the refrigerant to the evaporator (113); wherein the content of the first and second substances,

the first adjusting unit (130) includes: the absorption device comprises a first stop valve (133), a second stop valve (134), a third stop valve (135), a fourth stop valve (136), a first liquid storage tank (131) and a first auxiliary solution pump (132), wherein the absorber (111), the second stop valve (134), the first liquid storage tank (131), the third stop valve (135) and the first auxiliary solution pump (132) sequentially form a circulation loop, the first stop valve (133) is arranged on the first pipeline, and the fourth stop valve (136) is bridged at one ends of the third stop valve (135) and the first stop valve (133).

2. The absorption heat pump system according to claim 1, further comprising a solution heat exchanger (115), the first and second pipes exchanging heat through the solution heat exchanger (115).

3. The absorption heat pump system according to claim 1, the second conditioning unit (140) comprising: the generator comprises a fifth stop valve (143), a sixth stop valve (144), a seventh stop valve (145), an eighth stop valve (146), a second liquid storage tank (141) and a second auxiliary solution pump (142), wherein the generator (112), the sixth stop valve (144), the second liquid storage tank (141), the seventh stop valve (145) and the second auxiliary solution pump (142) sequentially form a circulation loop, the fifth stop valve (143) is arranged on the second pipeline, and the eighth stop valve (146) is bridged at one end of the fifth stop valve (143) and one end of the seventh stop valve (145).

4. The absorption heat pump system according to claim 3, further comprising a solution pump (121) on the first line.

5. The absorption heat pump system according to claim 4, further comprising a solution throttling valve (123) on the second line between the second conditioning unit (140) and the absorber (111).

6. A method of conditioning an absorption heat pump system according to claim 5, comprising:

before starting or changing load:

opening the second and sixth cut-off valves (134, 144) to direct a majority of the solution in the absorber (111) and generator (112) to the first and second tanks (131, 141);

at the time of starting or changing the load:

opening the first stop valve (133), the first auxiliary solution pump (132), the third stop valve (135), the fifth stop valve (143), the seventh stop valve (145), and the second auxiliary solution pump (142);

opening a solution throttle valve (123), a solution pump (121) and a refrigerant pump (122) to inject the solution in the first and second liquid storage tanks (131, 141) into the cycle;

opening the second stop valve (134) and the sixth stop valve (144), and closing the first auxiliary solution pump (132) and the second auxiliary solution pump (142) to store part of the solution in the first liquid storage tank (131) and the second liquid storage tank (141);

opening the fourth and eighth shut-off valves (136, 146) and closing the first and fifth shut-off valves (133, 143);

and after the system enters a normal operation state, closing the second stop valve (134) and the sixth stop valve (144).

7. The regulation method according to claim 6, wherein, before starting or varying the load, if the amount of solution in the absorber (111) or generator (112) is less than a first preset value, the third and seventh stop valves (135, 145) are opened and the first and second auxiliary solution pumps (132, 142) are started so that the amount of solution in the absorber (111) or generator (112) is greater than or equal to the first preset value.

8. The regulation method according to claim 6 or 7, wherein if the amount of solution in the first tank (131) is less than a second preset value, the second stop valve (134) is opened to introduce the solution in the absorber (111) into the first tank (131); and if the solution amount in the second liquid storage tank (141) is less than a third preset value, opening the sixth stop valve (144) to guide the solution in the generator (112) into the second liquid storage tank (141).