Return water waste heat recovery system for circulating water

Abstract

The utility model provides a circulating water return water waste heat recovery system which is characterized in that a compression type heat pump unit is arranged between a circulating water field and a municipal heat supply network water supply pipeline, heat of waste heat water in circulating water is transferred to return water in the municipal heat supply network water supply pipeline through the compression type heat pump unit, and heat supply network water supply is heated. And the waste heat water after heat recovery returns to the circulating water field. According to the system, the compression heat pump technology is adopted, efficient recycling of circulating water waste heat is achieved, and the waste heat recycling amount meets the regional heating requirement; the running number of fans of the circulating water field can be reduced, the electric quantity is saved, the heat dissipation and evaporation capacity of circulating water is reduced, the real-time water supplementing amount is reduced, and fresh water consumption is reduced; direct emission of waste heat is reduced, and thermal pollution is reduced.

Description

Technical Field

[0001] This utility model belongs to the field of waste heat recovery technology of circulating water in chemical production, specifically relating to a waste heat recovery system for circulating water return water using compression heat pump technology, which is suitable for efficient recovery and utilization of waste heat from circulating water. Background Technology

[0002] The circulating water system consists of 10 cooling towers, 2 tower pools, 2 suction pools, 5 circulating water pumps, 2 turbine units, and heat exchangers. This system supplies circulating cooling water at a pressure >0.4 MPa to the heat exchangers of the naphtha and hydrotreating tail oil pumps in the ethylene unit, styrene unit, feedstock tank area, and feedstock tank area, with a circulating water volume of 43,000 m³. 3 The circulating water supply temperature is 28℃, and the return water temperature is 35℃. The current design does not consider waste heat recovery from the circulating water, resulting in a significant waste of energy due to direct heat discharge. This not only causes production enterprises to consume more energy to maintain production and increase production costs, but also contradicts the environmental trend of energy conservation and emission reduction. Utility Model Content

[0003] (a) Technical problems to be solved

[0004] This invention proposes a waste heat recovery system for circulating water return water, which solves the problems of energy waste, high cost and pollution caused by the direct discharge of waste heat in existing circulating water systems. It achieves efficient recovery and utilization of waste heat from circulating water return water through compression heat pump technology, thereby reducing energy consumption and environmental pollution.

[0005] (II) Technical Solution

[0006] To solve the above-mentioned technical problems, this utility model proposes a circulating water return waste heat recovery system. The circulating water return waste heat recovery system sets up a compression heat pump unit between the circulating water field and the municipal heating network water supply pipeline. The compression heat pump unit transfers the heat of the waste hot water in the circulating water to the return water in the municipal heating network water supply pipeline to heat the heating network water supply. The waste hot water after heat recovery is returned to the circulating water field.

[0007] Furthermore, the compression heat pump unit includes multiple electric compression heat pumps.

[0008] Furthermore, the electric compression heat pump includes an evaporator, a condenser, a compressor, and a throttling device. The evaporator is connected to the circulating water field via two pipelines, and the condenser is connected to the heating network water supply pipeline via two pipelines. Waste water in the circulating water field is drawn from the waste heat network, pressurized by the waste water circulating pump, and enters the evaporator. By inputting electrical energy into the compressor as the circulation power, the refrigerant circulates and undergoes a phase change within the compression heat pump unit, extracting heat from the waste water flowing through the evaporator. After heat extraction, the temperature of the waste water drops, and it returns to the circulating water field via pipelines. The extracted heat in the condenser is transferred to the circulating water on the demand side to heat the return water in the heating network water supply pipeline.

[0009] Furthermore, the throttling device employs an expansion valve.

[0010] Furthermore, the compression heat pump unit includes 20 electric compression heat pumps.

[0011] Furthermore, the 20 electric compression heat pumps include 6 14.6MW electric compression heat pumps, 6 8.5MW electric compression heat pumps, 6 7.84MW electric compression heat pumps, and 2 12.6MW electric compression heat pumps.

[0012] Furthermore, based on the waste heat recovery requirements, corresponding types and quantities of electric compression heat pumps are selected and combined to jointly complete the waste heat recovery work of the circulating water return water.

[0013] Furthermore, the pipeline has a diameter of 1620 mm and a wall thickness of 12 mm.

[0014] (III) Beneficial Effects

[0015] This invention proposes a waste heat recovery system for circulating water return water. A compression heat pump unit is installed between the circulating water system and the municipal heating network supply pipeline. The compression heat pump unit transfers heat from the waste water in the circulating water to the return water in the municipal heating network supply pipeline, heating the supply water. The recovered waste water is then returned to the circulating water system. This system utilizes compression heat pump technology to achieve efficient recovery and utilization of waste heat from the circulating water, meeting the regional heating requirements. It reduces the number of fans operating in the circulating water system, saving electricity; it reduces heat loss and evaporation from the circulating water, decreasing the need for real-time water replenishment and saving fresh water consumption; and it reduces direct waste heat emissions, lowering thermal pollution. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the circulating water return waste heat recovery system of this utility model. Detailed Implementation

[0017] To make the objectives, contents, and advantages of this utility model clearer, the specific embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples.

[0018] This embodiment proposes a circulating water return waste heat recovery system, such as... Figure 1 As shown, the circulating water return waste heat recovery system has a compression heat pump unit installed between the circulating water field and the municipal heating network water supply pipeline. The compression heat pump unit transfers the heat of the waste hot water in the water vapor device to the return water in the municipal heating network water supply pipeline to heat the heating network water supply. The waste hot water after heat recovery is returned to the circulating water field of the water vapor device.

[0019] The compression heat pump unit comprises 20 electric compression heat pumps (6 units of 14.6MW, 6 units of 8.5MW, 6 units of 7.84MW, and 2 units of 12.6MW). Each electric compression heat pump consists of four key components: an evaporator, a condenser, a compressor, and a throttling device (expansion valve). The evaporator is connected to the circulating water system via two 1620mm diameter, 12mm wall thickness pipes, while the condenser is connected to the heating network supply water pipes via two pipes. Waste water at 35℃ in the circulating water system is drawn from the waste heat network, pressurized by the waste water circulating pump, and enters the evaporator. A small amount of electrical energy is input to the compressor as the circulation power, causing the refrigerant to circulate and undergo a phase change within the compression heat pump unit, extracting heat from the waste water flowing through the evaporator. After heat extraction, the waste water temperature drops to 28℃ and returns to the circulating water system via pipelines. The extracted heat is transferred to the demand-side circulating water in the condenser, heating the urban heating return water at 18℃ in the heating network supply water pipes.

[0020] Depending on the waste heat recovery requirements, corresponding types and quantities of electric compression heat pumps can be selected and combined to jointly complete the waste heat recovery work of circulating water return water.

[0021] The waste heat recovery system of this utility model can not only recover heat from the waste water in the circulating water field of the water vapor device for centralized heating of users in winter, achieving the goal of waste heat recovery and reuse, but also effectively reduce the water evaporated by the circulating water, thus achieving the dual effect of energy saving and emission reduction.

[0022] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A circulating water return waste heat recovery system, characterized in that, The circulating water return waste heat recovery system is equipped with a compression heat pump unit between the circulating water field and the municipal heating network water supply pipeline. The compression heat pump unit transfers the heat of the waste hot water in the circulating water to the return water in the municipal heating network water supply pipeline to heat the heating network water supply. The waste hot water after heat recovery is returned to the circulating water field.

2. The circulating water return waste heat recovery system as described in claim 1, characterized in that, The compression heat pump unit includes multiple electric compression heat pumps.

3. The circulating water return waste heat recovery system as described in claim 2, characterized in that, The electric compression heat pump includes an evaporator, a condenser, a compressor, and a throttling device. The evaporator is connected to the circulating water field via two pipelines, and the condenser is connected to the heating network water supply pipeline via two pipelines. Waste water in the circulating water field is drawn from the waste heat network, pressurized by the waste water circulating pump, and then enters the evaporator. By inputting electrical energy into the compressor as the circulation power, the refrigerant circulates and undergoes a phase change within the compression heat pump unit, extracting heat from the waste water flowing through the evaporator. After heat extraction, the temperature of the waste water drops, and it returns to the circulating water field via pipelines. The extracted heat in the condenser is transferred to the circulating water on the demand side to heat the return water in the heating network water supply pipeline.

4. The circulating water return waste heat recovery system as described in claim 3, characterized in that, The throttling device is an expansion valve.

5. The circulating water return waste heat recovery system as described in claim 2, characterized in that, The compression heat pump unit includes 20 electric compression heat pumps.

6. The circulating water return waste heat recovery system as described in claim 5, characterized in that, The 20 electric compression heat pumps include 6 14.6MW electric compression heat pumps, 6 8.5MW electric compression heat pumps, 6 7.84MW electric compression heat pumps, and 2 12.6MW electric compression heat pumps.

7. The circulating water return waste heat recovery system as described in claim 2, characterized in that, Based on the waste heat recovery requirements, select the appropriate type and quantity of electric compression heat pumps to combine and work together to complete the waste heat recovery of circulating water return water.

8. The circulating water return waste heat recovery system as described in claim 3, characterized in that, The pipeline has a diameter of 1620 mm and a wall thickness of 12 mm.

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