Search

CN-122014376-A - Step recovery and heat storage system of self-adaptive fluctuation industrial waste heat

CN122014376ACN 122014376 ACN122014376 ACN 122014376ACN-122014376-A

Abstract

The invention discloses a gradient recovery and heat storage system of self-adaptive fluctuation industrial waste heat, which comprises a parameter sensing and control subsystem, a low-temperature heat pump circulation subsystem, a high-temperature power generation circulation subsystem, a waste heat gradient heat exchange subsystem and a heat storage peak regulation subsystem, wherein the parameter sensing and control subsystem comprises a flow sensor and a temperature sensor which are arranged at an inlet of a waste heat conveying pipeline, and a central controller which is electrically connected with the flow sensor and the temperature sensor. By adopting an integrated design of parameter sensing, dynamic adjustment, gradient utilization and heat storage, the distributed sensing captures the parameters of the waste heat in real time, the high-temperature waste heat is directly led into a power generation module to drive a unit to generate power, the medium-temperature waste heat is directionally conveyed to a heat exchange module to prepare domestic or industrial hot water, the low-temperature waste heat is heated by a heat pump to prepare hot water, and when the flow of the waste heat is monitored to exceed the bearing capacity of the power generation/heat exchange module, the surplus waste heat is preferentially led into a heat storage unit to be stored, and the flow is gradually released to generate power or prepare the hot water after falling back.

Inventors

  • ZHANG KAI
  • DENG YAMIN

Assignees

  • 中科南京未来能源系统研究院

Dates

Publication Date
20260512
Application Date
20260122

Claims (9)

  1. 1. A cascade recovery and heat storage system for adaptive wave industrial waste heat, the system being configured to include: the parameter sensing and controlling subsystem comprises a flow sensor (13) arranged at the inlet of the waste heat conveying pipeline, a temperature sensor (14) and a central controller (15) electrically connected with the flow sensor (13) and the temperature sensor (14); The low-temperature heat pump circulation subsystem comprises a transcritical carbon dioxide heat pump circulation evaporator (1), a heat pump regenerator (2), a first compressor (3), a heat pump cooler (4) and a throttle valve (5); The high-temperature power generation circulation subsystem comprises a cooler (6), a second compressor (7), a high-temperature heat regenerator (8), a first valve (9), a second valve (10), an expander (11) and a generator (12); the waste heat cascade heat exchange subsystem comprises a high-temperature heater (19), a medium-temperature heater (20) and a low-temperature heat exchanger (21) which are sequentially arranged along the flow direction of waste heat; The heat storage peak shaving subsystem comprises: a first peak shaving heat storage tank (24) and a first peak shaving cold storage tank (25) for peak shaving of low temperature waste heat; the system comprises a second peak shaving cold storage tank (26), a first peak shaving heat exchanger (27), a second peak shaving heat storage tank (28), a first peak shaving heater (30) and an eighth valve (29) which are used for peak shaving of medium temperature waste heat; A third peak shaving cold storage tank (31), a second peak shaving heat exchanger (32), a third peak shaving heat storage tank (33), a second peak shaving heater (35) and a ninth valve (34) for peak shaving of high temperature waste heat; The central controller (15) is configured to control the opening degree of each valve and the start and stop of the first compressor (3) and the second compressor (7) according to data acquired by the flow sensor (13) and the temperature sensor (14).
  2. 2. The adaptive wave industrial waste heat step recovery and heat storage system of claim 1, further comprising a fluid control valve block: In the high-temperature power generation circulation subsystem, the first valve (9) is arranged on a connecting pipeline of the high-temperature heater (19) and the expander (11), and the second valve (10) is arranged on a connecting pipeline of the second peak shaver heater (35) and the expander (11); The waste heat cascade heat exchange subsystem is also provided with a third valve (16), a fourth valve (17) and a fifth valve (18); one end of the third valve (16) is connected with a waste heat conveying pipeline, and the other end of the third valve is connected with the second peak shaving heat exchanger (32); one end of the fifth valve (18) is connected with a waste heat conveying pipeline, and the other end of the fifth valve is connected with the first peak shaving heat exchanger (27); A sixth valve (22) and a seventh valve (23) for regulating the flow of hot water.
  3. 3. The cascade recovery and heat storage system of self-adaptive fluctuation industrial waste heat according to claim 1, wherein the cascade utilization connection relation of the system is: The low-temperature waste heat transfers heat to the first peak shaving heat storage tank (24) through the low-temperature heat exchanger (21), and after the heat of the first peak shaving heat storage tank (24) is absorbed by the heat pump working medium through the evaporator (1), the heat pump working medium sequentially flows through the heat pump regenerator (2) and the first compressor (3) to the heat pump cooler (4) to prepare hot water; The medium-temperature waste heat releases heat in the medium-temperature heater (20) for preparing hot water, and the residual heat enters the low-temperature heat exchanger (21); the high-temperature waste heat is used for heating the power generation circulating working medium through the high-temperature heater (19), the working medium drives the expander (11) to do work to drive the generator (12) to generate power, and the residual heat sequentially flows through the medium-temperature heater (20) and the low-temperature heat exchanger (21).
  4. 4. The cascade recovery and heat storage system of self-adaptive fluctuation industrial waste heat according to claim 2, wherein the heat storage peak shaving connection relation of the system is: when the flow of the waste heat exceeds the bearing upper limit of the power generation cycle and the heat pump cycle, the central controller (15) opens the third valve (16) or the fifth valve (18), and the surplus high-temperature waste heat or the surplus medium-temperature waste heat is respectively heated by the second peak shaving heat exchanger (32) or the first peak shaving heat exchanger (27) and is stored in the third peak shaving heat storage tank (33) or the second peak shaving heat storage tank (28), and the surplus low-temperature waste heat is stored in the first peak shaving heat storage tank (24) by the low-temperature heat exchanger (21); When the waste heat flow falls back or the energy consumption requirement increases, the central controller (15) opens the ninth valve (34) or the eighth valve (29), and the working medium in the third peak shaving heat storage tank (33) or the second peak shaving heat storage tank (28) or the first peak shaving heat storage tank (24) releases heat in the second peak shaving heater (35) or the first peak shaving heater (30) or the evaporator (1) respectively.
  5. 5. The cascade recovery and heat storage system for self-adaptive fluctuation industrial waste heat of claim 1, wherein the heat pump cycle working medium and the power generation cycle working medium are both carbon dioxide.
  6. 6. The gradient recovery and heat storage system of the self-adaptive fluctuation industrial waste heat according to claim 1, wherein the heat storage working medium in the third peak shaving heat storage tank (33) and the second peak shaving heat storage tank (28) is selected from one of potassium nitrate-sodium nitrate mixed molten salt, mineral oil type heat conduction oil or normal paraffin wax.
  7. 7. The gradient recovery and heat storage system of self-adaptive fluctuation industrial waste heat according to claim 1, wherein the working medium in the first peak shaving heat storage tank (24) is selected from one of water, glycol aqueous solution, propylene glycol aqueous solution or methanol aqueous solution.
  8. 8. The gradient recovery and heat storage system for self-adaptive fluctuation industrial waste heat according to claim 1, wherein the response time of the central controller (15) is less than or equal to 0.3s, the measurement precision of the temperature sensor (14) is less than or equal to +/-0.5 ℃, the measurement precision of the flow sensor (13) is less than or equal to +/-1%, and the sampling frequency is less than or equal to 0.5 s/time.
  9. 9. The gradient recovery and heat storage system for self-adaptive fluctuation industrial waste heat according to claim 1, wherein the low-temperature waste heat temperature of the system is 20-90 ℃, the medium-temperature waste heat temperature is 90-200 ℃, and the high-temperature waste heat temperature is 200-800 ℃; the fluctuation range of the waste heat flow of the system is +/-40%.

Description

Step recovery and heat storage system of self-adaptive fluctuation industrial waste heat Technical Field The invention belongs to the technical field of industrial waste heat recovery and heat storage, and particularly relates to a cascade recovery and heat storage system of self-adaptive fluctuation industrial waste heat. Background The industrial waste heat is used as secondary energy generated in the industrial production process, and has the characteristics of large total amount and wide distribution. However, the industrial waste heat generally has the problem of severe parameter fluctuation, the temperature of the industrial waste heat is often periodically fluctuated in the range of 150-800 ℃, the fluctuation range of the flow can reach +/-40%, and the period is difficult to predict. The existing main stream waste heat recovery equipment is generally designed based on stable working conditions, has obvious defects when coping with fluctuation waste heat, and is poor in low-grade waste heat and equipment matching performance, the efficiency of deviating from the design working conditions is greatly reduced, meanwhile, equipment faults, such as dry burning of a waste heat boiler or cracks of a heat exchanger, are easily caused by parameter mutation, supply and demand mismatch are serious, a large amount of available waste heat is wasted, and therefore, a high-efficiency recovery energy storage system capable of dynamically adapting to fluctuation of waste heat parameters is needed. Disclosure of Invention The invention aims to solve the problem that waste heat recovery equipment is usually designed based on stable working conditions and has defects when dealing with fluctuation waste heat, and provides a gradient recovery and heat storage system of self-adaptive fluctuation industrial waste heat. In order to achieve the above purpose, the present invention adopts the following technical scheme: a stepped recovery and heat storage system for adaptive wave industrial waste heat, the system configured to include: the parameter sensing and controlling subsystem comprises a flow sensor and a temperature sensor which are arranged at the inlet of the waste heat conveying pipeline, and a central controller which is electrically connected with the flow sensor and the temperature sensor; The low temperature heat pump circulation subsystem comprises a transcritical carbon dioxide heat pump circulation evaporator, a heat pump regenerator, a first compressor, a heat pump cooler and a throttle valve; the high-temperature power generation circulation subsystem comprises a cooler, a second compressor, a high-temperature heat regenerator, a first valve, a second valve, an expander and a generator; The waste heat cascade heat exchange subsystem comprises a high-temperature heater, a medium-temperature heater and a low-temperature heat exchanger which are sequentially arranged along the flow direction of waste heat; The heat storage peak shaving subsystem comprises: The first peak regulation heat storage tank and the first peak regulation cold storage tank are used for low-temperature waste heat peak regulation; a second peak regulation heat storage tank for medium temperature waste heat peak regulation a first peak regulating heat exchanger the second peak shaving cold storage tank, the first peak shaving heater and the eighth valve; a third peak regulation heat storage tank for peak regulation of high-temperature waste heat a second peak regulating heat exchanger the third peak shaving cold storage tank, the second peak shaving heater and the ninth valve; The central controller is configured to control the opening degree of each valve and the start and stop of the first compressor and the second compressor according to the data acquired by the flow sensor and the temperature sensor. As a further description of the above technical solution: The fluid control valve group also comprises: In the high-temperature power generation circulation subsystem, the first valve is arranged on a connecting pipeline of the high-temperature heater and the expander, and the second valve is arranged on a connecting pipeline of the second peak shaver heater and the expander; The waste heat cascade heat exchange subsystem is also provided with a third valve, a fourth valve and a fifth valve; one end of the third valve is connected with a waste heat conveying pipeline, and the other end of the third valve is connected with the second peak shaving heat exchanger; One end of the fifth valve is connected with a waste heat conveying pipeline, and the other end of the fifth valve is connected with the first peak shaving heat exchanger; a sixth valve and a seventh valve for regulating the flow of hot water. As a further description of the above technical solution: the cascade utilization connection relation of the system is as follows: the low-temperature waste heat transfers heat to the first peak shaving heat storage tank through the low-tempera