CN103398627A - Multi-source fluid waste heat recovery and comprehensive utilization system - Google Patents

Abstract

The invention discloses a multi-source fluid waste heat recovery and comprehensive utilization system, comprising a high-temperature heat exchanger, a heat source end heat exchanger group, a heat source end small circulation system, a direct heat exchange device, a thermal energy storage system, and a use end heat exchanger group , a waste heat utilization system, a heat pump system, and an intelligent control system, wherein the intelligent control system communicates with the high-temperature heat exchanger, the heat exchanger group at the heat source end, the small circulation system at the heat source end, the direct heat exchange device, the thermal energy storage system, Use side heat exchanger bank and heat pump system connection. The invention sets two independent internal circulations: it can prevent dirt and impurities in the water while ensuring the temperature of the heat source end of the heat pump, and can carry out separate physical and chemical treatment on the circulating water to ensure the water quality at the heat source end. In addition, the internal circulation isolates the heat pump from contact with liquids of different components, reducing the number of cleaning and maintenance, thereby ensuring the stability and reliability of the heat pump operation.

Description

A multi-source fluid waste heat recovery and comprehensive utilization system

technical field

The invention relates to multi-stage extraction and comprehensive utilization of waste heat in the production process of industrial enterprises, in particular to a multi-source fluid waste heat recovery and comprehensive utilization system.

Realize parallel flow of multiple heat sources, cascade extraction and utilization, intelligent working mode recognition and process control, improve the overall efficiency and working stability of the entire waste heat recovery system, and achieve low heat emission.

Background technique

A large part of the energy used by enterprises is wasted by waste heat. At the same time, in order to maintain the temperature of the medium, various methods are used for cooling, which consumes energy again. Waste heat exists in flue gas, cooling oil, cooling water, reclaimed water and sewage, etc. How to recover the heat energy, especially how to efficiently recover the heat energy from various waste heat sources at the same time and form a stable heat source has become a As an important development direction of energy saving and emission reduction, solving a series of scientific and technical problems encountered in co-current recovery of various waste heat energies has become an important theoretical and technical topic.

A large part of the energy used by enterprises is wasted by waste heat. At the same time, in order to maintain the temperature of the medium, various methods are used for cooling, which consumes energy again. Waste heat exists in flue gas, cooling oil, cooling water, reclaimed water and sewage. The existing waste heat recovery device only recovers heat energy for a certain heat source, and such a system has the following problems:

1. Limited by the actual situation of production, it is difficult to obtain a stable heat supply by using such a waste heat recovery system.

2. Due to the large temperature fluctuation at the input end of the heat pump unit, it is difficult to exert the maximum working efficiency and affect the service life.

3. It is difficult to actively control and adjust in the system, and the heat transfer ratio of the system cannot be optimal.

Contents of the invention

In order to solve the above-mentioned problems in the prior art, the present invention designs a multi-source fluid waste heat recovery and comprehensive utilization system that can improve the heat exchange ratio of the system, stabilize the temperature of the recovered heat source, and have high system reliability.

In order to achieve the above object, the technical solution of the present invention is as follows: a multi-source fluid waste heat recovery and comprehensive utilization system, including a high-temperature heat exchanger, a heat exchanger group at the heat source end, a small circulation system at the heat source end, a direct heat exchange device, and a thermal energy storage system, a heat exchanger group at the use end, a waste heat utilization system, a heat pump system, and an intelligent control system. Connection of heat exchange device, thermal energy storage system, use-side heat exchanger group and heat pump system;

The input end of the high-temperature heat exchanger is connected to a high-temperature heat source, and its output end is connected to a thermal energy storage system through a direct heat exchange device;

The heat source end heat exchanger group includes a group of heat exchangers with different structures and characteristic parameters, each heat exchanger is connected to the intelligent control system through a control cable, and the input end of the heat exchanger is connected to a corresponding non-high temperature The heat source is connected, and its output end is connected to the internal circulation system; the internal circulation system is connected to the thermal energy storage system through the heat pump system;

The use-end heat exchanger group includes a group of heat exchangers with different structures and characteristic parameters, each heat exchanger is connected to the intelligent control system through a control cable, and the input ends of the heat exchangers are connected to the thermal energy storage system , its output end is connected with a corresponding heat source;

The output end of the thermal energy storage system is also connected to a direct heating system;

The high-temperature heat exchanger and the heat source end heat exchanger together with the high temperature heat source and the non-high temperature heat source form a multi-source fluid heat exchange cycle system; the input of the heat source end heat exchanger group, the heat source end small circulation system and the heat pump system The internal circulation system of the heat source end is jointly formed at the heat source end; the output end of the heat pump system, the thermal energy storage system and the heat exchanger group at the use end jointly form a heat storage circulation system; the heat exchanger group at the use end and the waste heat utilization system form a comprehensive use the circulatory system;

The intelligent control algorithm of the described intelligent control system comprises the following steps:

a. Parallel extraction of multiple heat source fluids and heat exchange with the internal circulation of the heat source end of the heat pump. The control of each heat exchange adopts a fuzzy control algorithm to ensure the stability of the internal circulation water temperature; control the flow of heat by controlling the flow of heat source fluid Exchange, the fuzzy control algorithm is used as the execution layer of the control, and the valve opening of each channel of the multi-source fluid is determined according to the instruction of the amount of heat exchange;

b. Use the neural network to identify and learn the operation rules of multi-source fluids, as the instruction level of the fuzzy control algorithm; according to the requirements for the temperature stability of the thermal energy storage system, while considering the requirements for the cooling temperature of the multi-source fluids, combined with the actual situation of industrial production , the neural network self-adaptively learns and summarizes the thermal energy change law of multi-source fluid heat sources, and gives real-time heat exchange instructions for each channel of multi-source fluids according to network experience, and the fuzzy control algorithm controls the valve opening of each channel of multi-source fluids according to this instruction.

Each heat exchanger in the group of heat exchangers at the heat source end of the present invention has the most suitable structure and characteristic parameters for its corresponding heat source.

Each heat exchanger in the heat exchanger group at the use end of the present invention has the most suitable structure and characteristic parameters for its corresponding heat application system.

The working principle of the present invention is as follows: according to the different characteristics of multi-source fluids, different means of heat energy extraction are adopted, the heat exchanger at the heat source end selects different structures and characteristic parameters according to the properties of the fluids, and the internal circulation system isolates the multi-source fluids from the heat pump system Open, improve heat pump efficiency and stability and reliability of use. The thermal energy storage system receives the effluent from the heat source of the heat pump. On the one hand, it stores hot water, and at the same time, it also plays a role in regulating the overall thermal energy storage of the system. The use-side heat exchanger transfers the heat in the thermal energy storage system to the waste heat utilization system. The intelligent control system regulates the heat transfer process of the whole system.

Compared with the prior art, the present invention has the following beneficial effects:

1. The present invention sets up two independent internal circulations: it can prevent dirt and impurities in the water while ensuring the temperature of the heat source end of the heat pump, and can carry out separate physical and chemical treatment on the circulating water to ensure the water quality at the heat source end. In addition, the internal circulation isolates the heat pump from contact with liquids of different components, reducing the number of cleaning and maintenance, thereby ensuring the stability and reliability of the heat pump operation.

2. The present invention sets four sub-circulation systems to realize the independent heat exchange of each heat source fluid, to ensure the reliable operation of the heat pump, and the water quality and safety of hot water users.

3. The present invention adopts the intelligent heat exchange control of multi-source fluids: according to the characteristics and flow rules of each heat source fluid, the heat exchange time and heat exchange amount between it and the internal circulating water are controlled, so as to ensure that the cooled device or system is fully cooled. On the basis of cooling, various heat sources can complement each other to maximize heat exchange, and at the same time ensure that the temperature of the circulating water in the heat source end is basically constant, improving the working efficiency and durability of the heat pump;

4. The present invention is composed of four sub-circulation systems connected in series: multi-source fluid heat exchange cycle, heat source end internal cycle, heat storage cycle and comprehensive utilization cycle to realize independent heat exchange of each heat source fluid and ensure reliable operation of the heat pump. Hot water quality and safety for hot water users;

5. The present invention performs parallel extraction of various heat source fluids and conducts heat exchange with the internal circulation of the heat source end of the heat pump. The control of each heat exchange adopts a fuzzy control algorithm to ensure the stability of the internal circulation water temperature;

6. The multi-mode step extraction scheme and different heat characteristics of the present invention realize optimized step extraction and step utilization (tank car cleaning, heating during spraying, casting sand preheating, etc.). Different heat exchange methods are adopted for different heat sources, such as high-temperature heat source and non-high-temperature heat source, high-temperature heat source directly obtains heat, and non-high-temperature heat source obtains heat through a heat pump.

Description of drawings

The present invention only has 1 accompanying drawing, wherein:

Fig. 1 is a schematic structural view of the present invention.

In the figure: 1. Multi-source fluid heat source, 2. High temperature heat exchanger, 3. Small circulation system at the heat source end, 4. Direct heat exchange device, 5. Thermal energy storage system, 6. Heat exchanger group at the use end, 7. Waste heat Utilization system, 8. Heat pump system, 9. Intelligent control system, 10. Heat exchanger group at the heat source end.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings. As shown in Figure 1, a multi-source fluid waste heat recovery and comprehensive utilization system includes a high-temperature heat exchanger 2, a heat exchanger group 10 at the heat source end, a small circulation system 3 at the heat source end, a direct heat exchange device 4, and a thermal energy storage system 5 , use end heat exchanger group 6, waste heat utilization system 7, heat pump system 8 and intelligent control system 9, described intelligent control system 9 is respectively connected with high temperature heat exchanger 2, heat source end heat exchanger group 10, heat source through control cable The end small circulation system 3, the direct heat exchange device 4, the thermal energy storage system 5, the use end heat exchanger group 6 and the heat pump system 8 are connected;

The input end of the high-temperature heat exchanger 2 is connected to a high-temperature heat source, and its output end is connected to a thermal energy storage system 5 via a direct heat exchange device 4;

The heat source end heat exchanger group 10 includes a group of heat exchangers with different structures and characteristic parameters, each heat exchanger is connected to the intelligent control system 9 through a control cable, and the input end of the heat exchanger is connected to a corresponding The non-high temperature heat source is connected, and its output is connected to the internal circulation system; the internal circulation system is connected to the thermal energy storage system 5 through the heat pump system 8;

The heat exchanger group 6 at the use end includes a group of heat exchangers with different structures and characteristic parameters, each heat exchanger is connected to the intelligent control system 9 through a control cable, and the input ends of the heat exchangers are connected to the thermal energy storage The system 5 is connected, and its output is connected with a corresponding heat source;

The output end of the thermal energy storage system 5 is also connected with a direct heating system;

The high-temperature heat exchanger 2 and the heat source end heat exchanger together with the high temperature heat source and the non-high temperature heat source form a multi-source fluid heat exchange cycle system; the heat source end heat exchanger group 10, the heat source end small circulation system 3 and the heat pump The input end of the system 8 jointly forms a heat source end internal circulation system; the output end of the heat pump system 8, the thermal energy storage system 5 and the use-end heat exchanger group 6 jointly form a heat storage circulation system; the use-end heat exchanger Group 6 and waste heat utilization system 7 form a comprehensive utilization cycle system;

The intelligent control algorithm of described intelligent control system 9 comprises the following steps:

a. Parallel extraction of multiple heat source fluids and heat exchange with the internal circulation of the heat source end of the heat pump. The control of each heat exchange adopts a fuzzy control algorithm to ensure the stability of the internal circulation water temperature; control the flow of heat by controlling the flow of heat source fluid Exchange, the fuzzy control algorithm is used as the execution layer of the control, and the valve opening of each channel of the multi-source fluid is determined according to the instruction of the amount of heat exchange;

b. Use the neural network to identify and learn the operation rules of multi-source fluids, as the instruction level of the fuzzy control algorithm; according to the requirements for the temperature stability of the thermal energy storage system 5, and considering the requirements for the cooling temperature of the multi-source fluids, combined with the actual industrial production The neural network self-adaptively learns and summarizes the heat energy change law of the multi-source fluid heat source 1, and gives the heat exchange instructions of each channel of the multi-source fluid in real time according to the network experience, and the fuzzy control algorithm controls the valve opening of each channel of the multi-source fluid according to this instruction. Spend.

Each heat exchanger in the heat source end heat exchanger group 10 of the present invention has the most suitable structure and characteristic parameters for its corresponding heat source.

Each heat exchanger in the heat exchanger group 6 at the use end of the present invention has the most suitable structure and characteristic parameters for its corresponding heat application system.

The working principle of the present invention is as follows: according to the different characteristics of multi-source fluids, different heat energy extraction methods are adopted, and the heat exchanger at the heat source end selects different structures and characteristic parameters according to the properties of the fluids, and the internal circulation system combines the multi-source fluids with the heat pump system 8 Isolated to improve heat pump efficiency and use stability and reliability. The thermal energy storage system 5 receives the outlet water from the heat source end of the heat pump. On the one hand, it stores hot water, and at the same time, it also plays a role in regulating the overall thermal energy storage of the system. The heat exchanger at the use end transfers the heat in the thermal energy storage system 5 to the waste heat utilization system 7 . The intelligent control system 9 regulates the heat transfer process of the whole system.

From the perspective of the system, the present invention is divided into heat source system, heat exchange system of multi-heat source and internal circulation system of heat pump heat source, high-efficiency heat exchange and heat pump system 8, heat storage hot water system, multi-purpose heat exchange system and hot water delivery system etc. The medium-high temperature flue gas and high-temperature cooling oil pass through the heat exchanger and the direct heat exchange device to obtain higher temperature water directly into the water tank of the thermal energy storage system 5 or directly add other cooling water including hot cooling water as the water source for bathing water storage tank. For example, the cooling water of the air compressor is used as the heat source water, and the heat is exchanged into the internal circulation system through a high-efficiency heat exchanger; the cooling water of casting and forging is filtered and then exchanged into the internal circulation system through a heat exchanger. Reclaimed water, sewage, etc. exchange heat into the internal circulation system through the vertical tube heat exchanger. The heat pump system 8 extracts its low-quality heat energy and exchanges it into the water tank of the heat energy storage system 5 . After the heat source water passes through the plate heat exchanger, the internal circulating water system, heat pump unit, heat exchange flow control valve, etc. are added. The intelligent control system 9 controls the heat exchange flow and heat of each channel according to the conditions of each heat source water, so as to ensure the stability of the internal circulation water temperature, thereby ensuring the stability of the inlet water temperature at the heat source end of the heat pump, improving the cleanliness of the inlet water at the heat source end, thereby improving the stability and efficiency of the heat pump operation . The thermal energy extracted by the high-efficiency heat exchanger and the heat pump unit is stored in the water storage tank of the thermal energy storage system 5 . Just like the water side of the heat source, different heat exchange methods are adopted according to the different chemical components of the hot water. For example, the water used in the tank car cleaning system is strongly alkaline water, and acid and alkali resistant pumps and heat exchangers must be used in the system; The water used for bathing is drinking standard water and can be directly supplied by the water storage tank. At the same time, taking into account the difference in heat temperature, a stepped heating method is adopted to improve the efficiency of heat use.

The system adopts a computer control system based on PROFI-BUS network, which is composed of PLC, computer, electric energy meter, intelligent water supply system, pressure sensor, flow sensor, temperature sensor, etc., to realize automatic monitoring and computer management of equipment. It realizes seamless connection with the energy management system of the enterprise through Ethernet and improves the management level.

Claims (3)

1. multi-source fluid waste heat recovery and utilization system, it is characterized in that: comprise high-temperature heat exchanger (2), heat source side heat exchanger set (10), heat source side lesser circulation (3), direct heat switch (4), thermal energy storage system (5), use side heat exchanger set (6), bootstrap system (7), heat pump (8) and intelligence control system (9), described intelligence control system (9) by control cables respectively with high-temperature heat exchanger (2), heat source side heat exchanger set (10), heat source side lesser circulation (3), direct heat switch (4), thermal energy storage system (5), use side heat exchanger set (6) is connected with heat pump (8),

The input of described high-temperature heat exchanger (2) is connected with high temperature heat source, its output is connected with thermal energy storage system (5) through direct heat switch (4);

Described heat source side heat exchanger set (10) comprises one group of heat exchanger with different structure and characterisitic parameter, each heat exchanger all is connected to intelligence control system (9) by control cables, and the non high temperature thermal source that the input of heat exchanger is corresponding with connects, its output is connected with internal circulation system; Described internal circulation system is connected with thermal energy storage system (5) through heat pump (8);

Described use side heat exchanger set (6) comprises one group of heat exchanger with different structure and characterisitic parameter, each heat exchanger all is connected to intelligence control system (9) by control cables, and the input of heat exchanger all connects with thermal energy storage system (5), its output and corresponding being connected with thermal source;

The output of described thermal energy storage system (5) also directly is connected with hot system with one;

Described high-temperature heat exchanger (2) and heat source side heat exchanger and high temperature heat source and non high temperature thermal source form the multi-source fluid heat transfer circulatory system jointly; The input of described heat source side heat exchanger set (10), heat source side lesser circulation (3) and heat pump (8) forms the heat source side internal circulation system jointly; The output of described heat pump (8), thermal energy storage system (5) and use side heat exchanger set (6) form the heat accumulation circulatory system jointly; Described use side heat exchanger set (6) and bootstrap system (7) form the comprehensive utilization circulatory system;

The intelligent control algorithm of described intelligence control system (9) comprises the following steps:

A, to the various heating sources fluid carry out in parallel extract and with the Heat Pump source in loop heat exchange ，Mei road heat exchange control adopt FUZZY ALGORITHMS FOR CONTROL, the stability of circulating water temperature in guaranteeing; By the flow of control of heat source fluid, control the exchange of heat, FUZZY ALGORITHMS FOR CONTROL is as the execution level of controlling, and according to what instruction of heat exchange, determines the valve opening on each road of multi-source fluid;

B, utilize neural network recognization and learn the moving law of multi-source fluid, as the instruction level of FUZZY ALGORITHMS FOR CONTROL; According to the requirement to thermal energy storage system (5) temperature stabilization, consider simultaneously the requirement to multi-source fluid chilling temperature, in conjunction with the industrial production actual conditions, the neutral net adaptive learning is also summed up the heat energy Changing Pattern of multi-source heat source fluid (1), according to Internet Experience, provide in real time the heat exchange instruction on each road of multi-source fluid, FUZZY ALGORITHMS FOR CONTROL is controlled the valve opening on each road of multi-source fluid according to this instruction.

2. a kind of multi-source fluid according to claim 1 waste heat recovery and utilization system, it is characterized in that: each heat exchanger in described heat source side heat exchanger set (10) has the most suitable structure and characteristics parameter of thermal source corresponding to it.

3. a kind of multi-source fluid according to claim 1 waste heat recovery and utilization system, it is characterized in that: each heat exchanger in described use side heat exchanger set (6) has with it applying the most suitable structure and characteristics parameter of hot system.

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