Waste heat comprehensive utilization system

Abstract

The invention discloses a waste heat comprehensive utilization system, which comprises a waste heat utilization module, a load demand calculation module and a waste heat distribution module, and is characterized in that the waste heat distribution module obtains heat demand quantity according to the load demand calculation module and waste heat obtained by the waste heat utilization module; and distributing the obtained waste heat to a demand object matched with the heat demand quantity. According to the waste heat comprehensive utilization system disclosed by the invention, the waste heat utilization module, the load demand calculation module and the waste heat distribution module are linked, so that low-grade heat sources such as ventilation air methane waste heat, air compressor waste heat and mine water waste heat can be fully and comprehensively utilized, and a coal-fired boiler is replaced; the requirements for wellhead freezing prevention, staff bathing and heat supply of field office buildings and workshops in industrial fields are met.

Description

Technical Field

[0001] The invention belongs to the technical field of waste heat recovery, and in particular relates to a waste heat comprehensive utilization system. Background Art

[0002] In many industrial plants such as mines, many equipment will generate a lot of heat during operation. However, many plants now do not recycle and comprehensively utilize this waste heat, resulting in a large amount of resource waste, reduced economic benefits and failure to follow the correct direction of economical development and clean development.

[0003] Therefore, further improvements are made to the above problems. Summary of the invention

[0004] The main purpose of the present invention is to provide a waste heat comprehensive utilization system, which is linked through a waste heat utilization module, a load demand calculation module and a waste heat distribution module, so that the waste heat distribution module distributes the obtained waste heat to the demand object with matching heat demand according to the heat demand obtained by the load demand calculation module and the waste heat obtained by the waste heat utilization module, so as to realize the full and comprehensive utilization of low-grade heat sources such as exhaust air waste heat, air compressor waste heat, mine water waste heat, etc., replace coal-fired boilers, and solve the needs of industrial wellhead antifreeze, employee bathing, and heating of office buildings and factory buildings in the site.

[0005] To achieve the above objectives, the present invention provides a waste heat comprehensive utilization system, comprising a waste heat utilization module, a load demand calculation module and a waste heat allocation module, wherein the waste heat allocation module allocates the waste heat to demand objects matching the heat demand according to the heat demand obtained by the load demand calculation module and the waste heat obtained by the waste heat utilization module, wherein:

[0006] The waste heat utilization module includes an air compressor waste heat recovery unit, a mine exhaust air waste heat recovery unit, a mine drainage waste heat recovery unit and a solar energy recovery unit, wherein:

[0007] The air compressor waste heat recovery unit recovers the friction heat and compression heat generated during the operation of the air compressor, and uses the generated first waste heat for the first demand object (including hot water for bathing);

[0008] The mine exhaust air waste heat recovery unit operates the mine main fan, so that the mine exhaust air can fully exchange heat with the ground underground, and the generated second waste heat is used for the second demand object (including heat energy for heating industrial buildings and antifreeze of wellheads in winter);

[0009] The mine drainage waste heat recovery unit recovers the heat of the water source heat pump and uses the generated third waste heat for the third demand object (the need for heating of mining area buildings in winter and as a supplementary heat source for hot water for bathing);

[0010] The solar energy recovery unit utilizes the solar energy resources in its own area and uses the generated fourth waste heat for the fourth demand object (producing hot water for bathing and also for heating of ground buildings);

[0011] The load demand calculation module includes a bathing hot water calculation unit, a building heating load calculation unit and a wellhead antifreeze load calculation unit. The bathing hot water calculation unit is used to calculate the amount of hot water required for bathing in the area; the building heating load calculation unit is used to calculate the amount of heating required for the building; and the wellhead antifreeze load calculation unit is used to calculate the amount of heat required for wellhead antifreeze.

[0012] As a further preferred technical solution of the above technical solution, in the air compressor waste heat recovery unit, each air compressor is matched with a waste heat recovery unit, so that the air compressor and the waste heat recovery unit correspond to each other one by one and are controlled in linkage.

[0013] As a further preferred technical solution of the above technical solution, in the air compressor waste heat recovery unit, including air-cooled air compressor waste heat recovery and water-cooled air compressor waste heat recovery, two hot water storage tanks are set for each air compressor room: when one water tank is heated, the other hot water storage tank completes the hot water delivery and cold water replenishment action, and the two water tanks operate alternately (thereby ensuring that the prepared domestic hot water is continuously delivered to the large hot water storage tank on the roof of the joint building), wherein:

[0014] Electric valves are set for the inlet and outlet pipes of the hot water storage tank, and temperature sensors and liquid level sensors are set inside the hot water storage tank to realize automatic control of circulating heating, hot water delivery and cold water replenishment; when the water temperature in the hot water storage tank reaches the set temperature, the electric valve of the circulating heating pipe is closed, and the electric valve of the hot water delivery pipe is opened. At the same time, the electric valve on the circulating heating pipe of the other water tank is opened to heat the cold water in the other hot water storage tank; when all the hot water in this hot water storage tank is delivered to the designated location and the liquid level in the water tank reaches the set level, the electric valve on the hot water delivery pipe is closed, and the cold water replenishment electric valve is opened. After the water in the water tank is replenished to the set level, the replenishment electric valve is closed, and the heating of the other water tank is completed, and the above actions are repeated.

[0015] As a further preferred technical solution of the above technical solution, for the mine exhaust air waste heat recovery unit, a gas-liquid spray heat exchanger is arranged at the elbow of the concrete air duct of the exhaust air diffusion tower, and the exhaust air returning from the mine is heat exchanged with the atomized water sprayed through the nozzle. After the heat exchange is completed, the exhaust air is discharged into the air, and a water retaining regulating plate is arranged on the side wall of the diffusion tower. If the wind resistance of the exhaust air heat exchanger increases, some regulating dampers are appropriately opened to ensure smooth exhaust of the exhaust air;

[0016] The spray water is collected through the water collection trough and then gathered into the primary sedimentation tank to carry out primary precipitation of the coal rock particles and other pollutants in the air-deficient spray water. The spray water after primary precipitation is transported to the special sewage wide-channel heat exchanger through the submersible sewage pump to exchange heat with the circulating water on the heat source side of the machine room.

[0017] As a further preferred technical solution of the above technical solution, in the air compressor waste heat recovery unit, two water pumps are provided, one for use and one for backup, for the bathing hot water heating circulation pump and the bathing hot water delivery pump to ensure that the operation of the system is not affected when one is overhauled. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of a waste heat comprehensive utilization system of the present invention.

[0019] Figure 2 It is a schematic diagram of an air compressor waste heat recovery unit of a waste heat comprehensive utilization system of the present invention.

[0020] Figure 3 It is a schematic diagram of a mine exhaust air waste heat recovery unit of a waste heat comprehensive utilization system of the present invention. DETAILED DESCRIPTION

[0021] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art can think of other obvious variations. The basic principles of the present invention defined in the following description can be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not deviate from the spirit and scope of the present invention.

[0022] In the preferred embodiments of the present invention, those skilled in the art should note that the air compressor and the like involved in the present invention may be regarded as prior art.

[0023] Preferred embodiments.

[0024] like Figure 1-3 As shown, the present invention discloses a waste heat comprehensive utilization system, including a waste heat utilization module, a load demand calculation module and a waste heat distribution module, wherein the waste heat distribution module distributes the obtained waste heat to a demand object matching the heat demand according to the heat demand obtained by the load demand calculation module and the waste heat obtained by the waste heat utilization module, wherein:

[0025] The waste heat utilization module includes an air compressor waste heat recovery unit, a mine exhaust air waste heat recovery unit, a mine drainage waste heat recovery unit and a solar energy recovery unit, wherein:

[0026] The air compressor waste heat recovery unit recovers the friction heat and compression heat generated during the operation of the air compressor, and uses the generated first waste heat for the first demand object (including hot water for bathing);

[0027] The mine exhaust air waste heat recovery unit operates the mine main fan, so that the mine exhaust air can fully exchange heat with the ground underground, and the generated second waste heat is used for the second demand object (including heat energy for heating industrial buildings and antifreeze of wellheads in winter);

[0028] The mine drainage waste heat recovery unit recovers the heat of the water source heat pump and uses the generated third waste heat for the third demand object (the need for heating of mining area buildings in winter and as a supplementary heat source for hot water for bathing);

[0029] The solar energy recovery unit utilizes the solar energy resources in its own area and uses the generated fourth waste heat for the fourth demand object (producing hot water for bathing and also for heating of ground buildings);

[0030] The load demand calculation module includes a bathing hot water calculation unit, a building heating load calculation unit and a wellhead antifreeze load calculation unit. The bathing hot water calculation unit is used to calculate the amount of hot water required for bathing in the area; the building heating load calculation unit is used to calculate the amount of heating required for the building; and the wellhead antifreeze load calculation unit is used to calculate the amount of heat required for wellhead antifreeze.

[0031] Specifically, in the air compressor waste heat recovery unit, each air compressor is matched with a waste heat recovery unit, so that the air compressor and the waste heat recovery unit correspond one to one and are controlled in linkage (when the air compressor corresponding to the waste heat recovery device is shut down, the air compressor waste heat recovery device is stopped at the same time and the corresponding electric valve is closed; when the air compressor corresponding to the waste heat recovery device is started, the waste heat recovery device is started at the same time, and the electric valve is opened to allow the cold bath water and the air compressor cooling oil to fully exchange heat and recover heat energy).

[0032] More specifically, in the air compressor waste heat recovery unit, including air-cooled air compressor waste heat recovery and water-cooled air compressor waste heat recovery, two hot water storage tanks are set for each air compressor room: when one water tank is heated, the other hot water storage tank completes the hot water delivery and cold water replenishment action, and the two water tanks operate alternately (thereby ensuring that the prepared domestic hot water is continuously delivered to the large hot water storage tank on the roof of the joint building), wherein:

[0033] Electric valves are set for the inlet and outlet pipes of the hot water storage tank, and temperature sensors and liquid level sensors are set inside the hot water storage tank to realize automatic control of circulating heating, hot water delivery and cold water replenishment; when the water temperature in the hot water storage tank reaches the set temperature, the electric valve of the circulating heating pipe is closed, and the electric valve of the hot water delivery pipe is opened. At the same time, the electric valve on the circulating heating pipe of the other water tank is opened to heat the cold water in the other hot water storage tank; when all the hot water in this hot water storage tank is delivered to the designated location and the liquid level in the water tank reaches the set level, the electric valve on the hot water delivery pipe is closed, and the cold water replenishment electric valve is opened. After the water in the water tank is replenished to the set level, the replenishment electric valve is closed, and the heating of the other water tank is completed, and the above actions are repeated.

[0034] More specifically, for the mine exhaust air waste heat recovery unit, a gas-liquid spray heat exchanger is installed at the elbow of the concrete air duct of the exhaust air diffusion tower, and the exhaust air returning from the mine exchanges heat with the atomized water sprayed through the nozzle. After the heat exchange is completed, the exhaust air is discharged into the air, and a water retaining regulating plate is installed on the side wall of the diffusion tower. If the wind resistance of the exhaust air heat exchanger increases, some regulating dampers are appropriately opened to ensure smooth exhaust of the exhaust air;

[0035] The spray water is collected through the water collection trough and then gathered into the primary sedimentation tank to carry out primary precipitation of the coal rock particles and other pollutants in the air-deficient spray water. The spray water after primary precipitation is transported to the special sewage wide-channel heat exchanger through the submersible sewage pump to exchange heat with the circulating water on the heat source side of the machine room.

[0036] More specifically, in the air compressor waste heat recovery unit, two water pumps are provided, one for use and one for backup, for the hot water heating circulation pump and the hot water delivery pump for bathing, to ensure that the operation of the system is not affected when one pump is overhauled.

[0037] For the calculation of the bathing domestic hot water calculation unit:

[0038] Assume that there are about 500 people bathing every day, with 3 shifts and about 170 people bathing in each shift. The shower water quota is 150L / person, and the daily shower water consumption is: 500 people × 150L / person = 75m 3 The total water consumption per day is 75m 3 . Hot water temperature is 45℃ (excluding water used for bathing).

[0039] For the calculation of the building heating load calculation unit:

[0040] Assuming that the ground heating building area of ​​the mine is about 6,000 m2, the calculated temperature of indoor heating of the ground building meets the requirements of the coal industry mine design specifications:

[0041] (1) Important light operation workshops are 16-18℃;

[0042] (2) Generally, the temperature in a light operation workshop is 14-16℃;

[0043] (3) Heavy-duty workshops and production system buildings with few operators should be 10-12°C;

[0044] (4) The temperature of hot working workshops, belt conveyor bridges, warehouses, etc. is 5-8℃;

[0045] (5) Administrative welfare and civil buildings: 18-20℃;

[0046] The heating volume heat index is used to calculate the heating design heat load of industrial buildings. The calculation formula is as follows:

[0047] Q n =q v V w (t n -t w )×10 -3

[0048] Where: ——Heating design heat load of the building, KW;

[0049] V w ——The outer volume of the building, m 3 ;

[0050] t n ——Calculated temperature in the heating room, °C;

[0051] t w ——The calculated temperature outside the heating area is -12℃;

[0052] q v ——Heating volume heat index of the building.

[0053] Substituting the data into the above formula and summarizing the calculations, the total heat load for ground building heating design is approximately 650KW.

[0054] For the calculation of wellhead antifreeze load calculation unit:

[0055] The mine air intake is about 7600m 3 / min, the lowest temperature in winter is -26.5℃, the average lowest temperature is calculated as -16.7℃, the relative humidity of return air is 46%, and the dry air density is about 1.26kg / m 3 According to this ambient temperature, the required heating load for wellhead antifreeze is calculated as:

[0056] Maximum heating load for wellhead antifreeze:

[0057] Q=1.10×1.26kg / m 3 ×127m 3 / s×1.01KJ / (kg)×(2℃+26.5℃)

[0058] =5067kW

[0059] Calculated based on an ambient temperature of -20°C, the antifreeze load is 3911kW.

[0060] It is worth mentioning that the technical features such as the air compressor involved in the patent application of this invention should be regarded as the prior art. The specific structure, working principle and possible control method and spatial layout method of these technical features can be selected by conventional methods in the field, and should not be regarded as the inventive point of this patent. This patent will not be further elaborated.

[0061] For those skilled in the art, it is still possible to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A waste heat comprehensive utilization system, characterized in that: It includes a waste heat utilization module, a load demand calculation module and a waste heat allocation module. The waste heat allocation module allocates the waste heat to demand objects that match the heat demand according to the heat demand obtained by the load demand calculation module and the waste heat obtained by the waste heat utilization module, wherein: The waste heat utilization module includes an air compressor waste heat recovery unit, a mine exhaust air waste heat recovery unit, a mine drainage waste heat recovery unit and a solar energy recovery unit, wherein: The air compressor waste heat recovery unit recovers the friction heat and compression heat generated during the operation of the air compressor, and uses the generated first waste heat for the first demand object; The mine exhaust air waste heat recovery unit operates the mine main fan, so that the mine exhaust air fully exchanges heat with the ground underground, and uses the generated second waste heat for the second demand object; The mine drainage waste heat recovery unit recovers the heat of the water source heat pump and uses the generated third waste heat for the third demand object; The solar energy recovery unit utilizes the solar energy resources in its own area and uses the generated fourth waste heat for the fourth demand object; The load demand calculation module includes a bathing hot water calculation unit, a building heating load calculation unit and a wellhead antifreeze load calculation unit. The bathing hot water calculation unit is used to calculate the amount of hot water required for bathing in the area; the building heating load calculation unit is used to calculate the amount of heating required for the building; and the wellhead antifreeze load calculation unit is used to calculate the amount of heat required for wellhead antifreeze.

2. The waste heat comprehensive utilization system according to claim 1, characterized in that: In the air compressor waste heat recovery unit, each air compressor is matched with a waste heat recovery unit, so that the air compressor and the waste heat recovery unit correspond to each other one by one and are controlled in linkage.

3. A waste heat comprehensive utilization system according to claim 2, characterized in that: In the air compressor waste heat recovery unit, there are air-cooled air compressor waste heat recovery and water-cooled air compressor waste heat recovery. Two hot water storage tanks are set for each air compressor room: when one water tank is heated, the other hot water storage tank completes the hot water delivery and cold water replenishment action, and the two water tanks operate alternately, wherein: Electric valves are set for the inlet and outlet pipes of the hot water storage tank, and temperature sensors and liquid level sensors are set inside the hot water storage tank to realize automatic control of circulating heating, hot water delivery and cold water replenishment; when the water temperature in the hot water storage tank reaches the set temperature, the electric valve of the circulating heating pipe is closed, and the electric valve of the hot water delivery pipe is opened. At the same time, the electric valve on the circulating heating pipe of the other water tank is opened to heat the cold water in the other hot water storage tank; when all the hot water in this hot water storage tank is delivered to the designated location and the liquid level in the water tank reaches the set level, the electric valve on the hot water delivery pipe is closed, and the cold water replenishment electric valve is opened. After the water in the water tank is replenished to the set level, the replenishment electric valve is closed, and the heating of the other water tank is completed, and the above actions are repeated.

4. A waste heat comprehensive utilization system according to claim 3, characterized in that: For the mine exhaust air waste heat recovery unit, a gas-liquid spray heat exchanger is installed at the elbow of the concrete air duct of the exhaust air diffusion tower. The exhaust air coming back from the mine exchanges heat with the atomized water sprayed through the nozzle. After the heat exchange is completed, the exhaust air is discharged into the air. A water retaining regulating plate is installed on the side wall of the diffusion tower. If the wind resistance of the exhaust air heat exchanger increases, some regulating dampers are appropriately opened to ensure smooth exhaust of the exhaust air. The spray water is collected through the water collection trough and then gathered into the primary sedimentation tank to carry out primary precipitation of the coal rock particles and other pollutants in the air-deficient spray water. The spray water after primary precipitation is transported to the special sewage wide-channel heat exchanger through the submersible sewage pump to exchange heat with the circulating water on the heat source side of the machine room.

5. The waste heat comprehensive utilization system according to claim 3, characterized in that: In the air compressor waste heat recovery unit, two water pumps are provided, one for use and one for backup, for the hot water heating circulation pump and the hot water delivery pump, to ensure that the operation of the system is not affected when one pump is overhauled.

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