Biomass power station cold source waste heat utilization device and heating system

Abstract

This utility model discloses a device and heating system for utilizing waste heat from a biomass power plant. The device includes a hot-end regulating module and a cold-end regulating module. The hot-end regulating module includes a condenser and an insulation pool, with the condenser connected to the insulation pool. The cold-end regulating module includes a low-temperature heat user unit, a first high-temperature heat user unit, a second high-temperature heat user unit, a power source heat pump unit, and a steam source heat pump unit. Multiple low-temperature heat user units are cyclically connected to the insulation pool, the power source heat pump unit is connected to the insulation pool and the first high-temperature heat user unit, and the steam source heat pump unit is connected to the insulation pool and the second high-temperature heat user unit. This application recovers waste heat from the generator unit through the condenser and insulation pool, thereby improving the overall thermal efficiency of the biomass power plant. The system adopts a cascaded utilization method for thermal energy, achieving efficient and graded energy utilization. Heating increases non-electricity revenue, enhancing the project's economic sustainability.

Description

Technical Field

[0001] This utility model relates to the field of biomass power generation technology, specifically to a device for utilizing waste heat from a cold source in a biomass power plant and a heating system. Background Technology

[0002] Currently, biomass power generation, as an important form of renewable energy utilization, occupies a certain position in my country's energy structure. Traditional biomass power generation projects mostly employ condensing or extraction-condensing steam turbine generator sets, designed primarily for power generation, resulting in generally low overall plant thermal efficiency. With the gradual phasing out of national electricity price subsidies, the economic viability of many biomass power generation projects faces severe challenges. Simultaneously, rising biomass fuel market prices and fluctuating fuel quality further exacerbate the operational pressure on power plants, with some projects even facing the risk of shutdown.

[0003] In existing technologies, biomass power plants typically employ high-temperature, high-pressure extraction condensing units. The condenser operates under vacuum conditions, making it difficult to effectively recover and utilize the heat lost from the cooling source. During the operation of pure condensing units, the exhaust steam from the turbine enters the condenser, and its latent heat of vaporization is carried away by circulating cooling water, ultimately being discharged into the atmosphere through a cooling tower. This heat loss from the cooling source accounts for more than 50% of the boiler's heat absorption, resulting in significant energy waste.

[0004] Therefore, existing biomass power plants face the technical challenge of improving the overall utilization rate of fuel. Utility Model Content

[0005] The purpose of this application is to overcome the above-mentioned technical deficiencies and propose a biomass power plant cold source waste heat utilization device and heating system to solve the technical problem of fuel comprehensive utilization rate in the prior art.

[0006] To achieve the above-mentioned technical objectives, this application adopts the following technical solution:

[0007] In a first aspect, this application provides a biomass power plant cold source waste heat utilization device, including a hot end regulation module and a cold end regulation module.

[0008] The hot-end regulating module includes a condenser and an insulation tank, wherein the condenser is connected to the insulation tank;

[0009] The cold-end regulation module includes a low-temperature heat user unit, a first high-temperature heat user unit, a second high-temperature heat user unit, an electric source heat pump unit, and a steam source heat pump unit. The multiple low-temperature heat user units are respectively connected to the insulation pool in a loop. The electric source heat pump unit is connected to the insulation pool and the first high-temperature heat user unit respectively. The steam source heat pump unit is connected to the insulation pool and the second high-temperature heat user unit respectively.

[0010] In some embodiments of this application, the heat-insulating pool includes a pool body and a heat-insulating layer. The pool body has a hollow inner cavity with a rectangular cross-sectional profile, and the heat-insulating layer covers the inner wall of the pool body.

[0011] In some embodiments of this application, the heat preservation tank includes a float level controller and a flow regulating valve. The float level controller is disposed in the inner cavity of the tank body, and the flow regulating valve is disposed in the pipeline between the condenser and the heat preservation tank.

[0012] In some embodiments of this application, the heat preservation pool includes a temperature sensor disposed in the inner cavity of the pool body.

[0013] In some embodiments of this application, the low-temperature heat user unit includes multiple plate heat exchanger groups, each of the plate heat exchanger groups includes a heat source cavity and a terminal cavity, the heat source cavity covers the terminal cavity, and the inlet and outlet of the heat source cavity are both connected to the insulation pool.

[0014] In some embodiments of this application, the low-temperature heat user unit includes a heating pipe network and a drying device, and the terminal cavity of the plate heat exchanger group is connected to the heating pipe network and the drying device respectively.

[0015] In some embodiments of this application, the low-temperature heat user unit includes an inlet water main pipe and a return water main pipe, and multiple plate heat exchanger groups are connected in parallel to each other and are all connected to the inlet water main pipe and the return water main pipe.

[0016] In some embodiments of this application, the low-temperature heat user unit includes a filter screen, which is disposed in a pipe between the outlet of the heat source cavity and the heat preservation pool.

[0017] Secondly, this application also provides a heating system, including a boiler, a generator set, and a biomass power plant cold source waste heat utilization device as described in any embodiment of the first aspect, wherein the boiler is connected to the generator set, and the generator set is connected to the condenser.

[0018] In some embodiments of this application, the boiler is connected to the steam source heat pump unit, and the generator set is connected to the steam source heat pump unit.

[0019] Compared with the prior art, the beneficial technical effects of the technical solution provided in this application include:

[0020] This application utilizes a condenser and insulation pool to recover waste heat from the generator set, storing and utilizing the low-grade heat energy lost from traditional cooling towers, thereby improving the overall thermal efficiency of the biomass power plant. The system adopts a cascaded utilization method for heat energy, with low-temperature users directly utilizing waste heat from the insulation pool, while the power source and steam source heat pump units respectively enhance the heat grade to meet the heating needs of high-temperature users, achieving efficient and tiered utilization of energy. The power source or steam source can be generated by the power plant itself, reducing external energy consumption. At the same time, waste heat recovery can reduce fuel costs and effectively alleviate the operating pressure caused by rising fuel prices. In the context of the reduction in electricity price subsidies, this scheme enhances the economic sustainability of the project by increasing non-electricity revenue through heating. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in this application, the accompanying drawings used in the embodiments will be briefly described below:

[0022] Figure 1 This is a schematic diagram of the structure of a biomass power plant cold source waste heat utilization device in an embodiment of this application.

[0023] Figure label:

[0024] 1-Hot end adjustment module, 2-Cold end adjustment module;

[0025] 11-Condenser, 12-Insulation pool;

[0026] 21-Low-temperature heat user unit, 22-First high-temperature heat user unit, 23-Second high-temperature heat user unit, 24-Power source heat pump unit, 25-Steam source heat pump unit. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0028] Those skilled in the art will understand that, in this specification, the term "comprising" is an open-ended expression, meaning that the stated feature is present but other features are excluded. Directional terms such as "upper," "lower," "left," and "right" refer to exemplary directions based on the accompanying drawings. Features specified as "first" or "second" implicitly include one or more of that feature. Singular expressions can also be used in plural forms. "Multiple" means two or more. The terms "installed," "connected," and "linked" can refer to a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection via an intermediate medium, and it can be a connection within two components. Furthermore, "linked" can include wireless connections.

[0029] The purpose of this application is to overcome the above-mentioned technical deficiencies and propose a biomass power plant cold source waste heat utilization device and heating system to solve the technical problem of fuel comprehensive utilization rate in the prior art.

[0030] To achieve the above-mentioned technical objectives, this application adopts the following technical solution:

[0031] like Figure 1 As shown. In a first aspect, this application provides a biomass power plant cold source waste heat utilization device, including a hot end regulating module 1 and a cold end regulating module 2.

[0032] The hot-end regulating module 1 includes a condenser 11 and an insulation pool 12, with the condenser 11 connected to the insulation pool 12. Circulating cooling water discharged from the condenser 11 by the turbine unit is introduced into the regulating insulation pool 12. The regulating insulation pool 12 is an insulated pool, and the heat brought in by the circulating cooling water serves as the heat source for the insulation pool 12. Various heat users constitute the cold end of the insulation pool 12. The regulating insulation pool 12 acts as a heat buffer, maintaining a balance between the waste heat supply from the condenser 11 and the heat demand of the heat users.

[0033] The regulation and control of the heat source end of the insulation pool 12, including the water temperature, the turbine exhaust vacuum, and the cooling tower, constitutes the control mechanism for the insulation pool 12. When heat demand increases, the water temperature in the insulation pool 12 decreases, and the system automatically reduces the cooling tower's drainage volume, increasing the vacuum of the condenser 11 (lowering the exhaust temperature), thereby increasing waste heat recovery. When heat demand decreases, excess heat is dissipated through the cooling tower to prevent overheating of the insulation pool 12, which could lead to increased back pressure in the condenser 11 (affecting power generation efficiency). The cooling tower serves as an emergency heat dissipation channel, activating when the insulation pool 12 reaches heat storage saturation or when heat demand is interrupted, ensuring the turbine always operates at the optimal vacuum level.

[0034] The cold end regulation module 2 includes a low-temperature heat user unit 21, a first high-temperature heat user unit 22, a second high-temperature heat user unit 23, an electric source heat pump unit 24, and a steam source heat pump unit 25. The multiple low-temperature heat user units are respectively connected to the insulation pool 12 in a loop. The electric source heat pump unit 24 is connected to the insulation pool 12 and the first high-temperature heat user unit 22 respectively. The steam source heat pump unit 25 is connected to the insulation pool 12 and the second high-temperature heat user unit 23 respectively.

[0035] The cold end of the insulated pool 12 serves the users and is divided into two parts: a high-temperature user section and a low-temperature user section. The low-temperature user section is directly pressurized and supplied to users by the circulating pump in the insulated pool 12. The low-temperature water used by the users is returned to the insulated pool 12. The high-temperature user section uses a heat pump system to heat the pool water to the required temperature before supplying it to the users. The high-level energy source for the heat pump system can utilize surplus electricity from the power plant and newly generated steam from the boiler. The high-temperature and low-temperature user sections constitute the cold end control and regulation link. The heat source control link of the insulated pool 12 and the cold end control link of the heat users constitute the biomass power plant's cold source utilization control system.

[0036] This application utilizes the condenser 11 and the insulation pool 12 to recover the waste heat from the generator set, storing and utilizing the low-grade heat energy lost by traditional cooling towers, thereby improving the overall thermal efficiency of the biomass power plant. The system adopts a cascaded utilization method of heat energy, with low-temperature users directly utilizing the waste heat from the insulation pool 12, and the power source and steam source heat pump units 25 respectively improving the heat grade to meet the heating needs of high-temperature users, achieving efficient and graded utilization of energy. The power source or steam source can be generated by the power plant itself, reducing external energy consumption. At the same time, waste heat recovery can reduce fuel costs and effectively alleviate the operating pressure caused by rising fuel prices. In the context of the reduction of electricity price subsidies, this scheme increases non-electricity income through heating, enhancing the economic sustainability of the project.

[0037] In some embodiments of this application, the heat-insulating pool 12 includes a pool body and a heat-insulating layer. The pool body has a hollow inner cavity with a rectangular cross-sectional profile, and the heat-insulating layer covers the inner wall of the pool body.

[0038] The insulated pool 12 features a rectangular cross-section design, achieving large-capacity heat storage through optimized aspect ratio, with the water inside forming a stable heat storage unit. The insulation layer uses nano-aerogel composite material, combined with a floating insulation cover, significantly reducing heat loss. The rectangular outline facilitates modular layout, allowing adjacent pools to share side walls to save space. The inner wall employs a composite structure of stainless steel cladding and insulation layer, providing both corrosion resistance and heat preservation.

[0039] In some embodiments of this application, the heat preservation tank 12 includes a float level controller and a flow regulating valve. The float level controller is disposed in the inner cavity of the tank body, and the flow regulating valve is disposed in the pipeline between the condenser 11 and the heat preservation tank 12.

[0040] This control system monitors the water level in the tank in real time using a float-type level controller. When the water level falls below the set value, it automatically adjusts the opening of the flow regulating valve to control the amount of circulating cooling water replenished, thus maintaining a stable water level in the tank. This system features fast response and high adjustment accuracy, effectively preventing a decrease in heat exchange efficiency caused by water level fluctuations.

[0041] In some embodiments of this application, the heat preservation pool 12 includes a temperature sensor disposed in the inner cavity of the pool body.

[0042] Temperature sensors monitor the water temperature changes within the insulation tank 12 in real time and feed the data back to the control system. When the water temperature is detected to be below a set threshold, the flow regulating valve automatically adjusts its opening to increase the injection of high-temperature circulating water; when the water temperature reaches the upper limit, the flow rate is reduced to achieve dynamic thermal balance. This scheme employs multi-point distributed temperature monitoring (arranged in upper, middle, and lower layers) combined with a PID control algorithm to ensure a uniform and stable temperature field within the tank. Both the temperature sensors and regulating valves are made of corrosion-resistant materials, ensuring automatic control accuracy while being maintenance-free, significantly reducing operating and maintenance costs.

[0043] In some embodiments of this application, the low-temperature heat user unit 21 includes multiple plate heat exchanger groups, each of the plate heat exchanger groups including a heat source cavity and a terminal cavity, the heat source cavity covering the terminal cavity, and the inlet and outlet of the heat source cavity being connected to the heat preservation pool 12.

[0044] In the nested plate heat exchanger assembly, the heat source cavity completely encloses the terminal cavity to form a dual-loop structure. High-temperature circulating water enters the heat source cavity from the insulation tank 12 and then transfers heat to the user-side medium in the terminal cavity through large-area corrugated plates. The cooled water, after heat exchange, returns to the insulation tank 12 for reheating. This structure improves heat exchange efficiency by increasing the heat exchange area and extending the medium residence time, and the comprehensive enclosure of the terminal cavity by the heat source cavity effectively reduces heat loss.

[0045] In some embodiments of this application, the low-temperature heat user unit 21 includes a heating pipe network and a drying device, and the terminal cavity of the plate heat exchanger group is connected to the heating pipe network and the drying device respectively.

[0046] This embodiment recovers waste heat from the turbine generator set's cold source through a heat exchange system, converting it into medium-temperature hot water which is then supplied to the heating system and the fuel drying system. The heating system employs a low-temperature return water design, while the drying system achieves efficient evaporation of moisture from the fuel through multi-stage heat exchange. This solution significantly improves energy utilization efficiency while reducing fuel processing energy consumption, achieving cascaded utilization of waste heat from the cold source, and yielding significant economic and environmental benefits.

[0047] The low-end heat users can directly supply heat to users by using the circulating hot water in the heat preservation pool 12, which can meet the users' needs for heating, fuel drying, drying, constant temperature breeding and other needs.

[0048] In some embodiments of this application, the low-temperature heat user unit 21 includes an inlet water main pipe and a return water main pipe, and multiple plate heat exchanger groups are connected in parallel to each other and are all connected to the inlet water main pipe and the return water main pipe.

[0049] In this embodiment, the waste heat from the insulation pool 12 is transferred to the low-temperature heat user unit 21 via a parallel plate heat exchanger assembly. After use by the heat user, the low-temperature water returns to the insulation pool 12 for recycling through the return water trunk line. This design achieves closed-loop recovery of waste heat from the cold source, improves heat exchange efficiency, reduces system heat loss, and has the advantages of compact structure, stable operation, and high thermal energy utilization, effectively improving the overall energy efficiency of the biomass power plant.

[0050] In some embodiments of this application, the low-temperature heat user unit 21 includes a filter screen plate disposed in a pipe between the outlet of the heat source cavity and the heat preservation pool 12.

[0051] This embodiment incorporates a stainless steel filter screen in the outlet pipe of the heat source chamber, effectively intercepting particulate impurities generated during heat exchange and preventing pipe blockage and scale buildup in the heat exchanger. This design extends the system maintenance cycle, maintains stable heat exchange efficiency, and features a quick-release structure for easy cleaning and maintenance, thus improving overall operational reliability. It is particularly suitable for operating conditions with poor circulating water quality in biomass power plants.

[0052] Secondly, this application also provides a heating system, including a boiler, a generator set, and a waste heat utilization device for a biomass power plant cold source as described in any embodiment of the first aspect, wherein the boiler is connected to the generator set, and the generator set is connected to the condenser 11.

[0053] The biomass power plant cold source utilization control system uses the calculation of the waste heat from the turbine exhaust and the heat consumption at the user end to control the overall stability of the system.

[0054] This heating system achieves efficient utilization of waste heat from the cold source through dynamic balance control. The system monitors the waste heat from the turbine exhaust steam and the user's heat demand in real time. When an imbalance occurs, a compensation mechanism is automatically activated: when excess waste heat causes the temperature of the insulation pool 12 to exceed a set threshold, the system automatically diverts a portion of the circulating water to the cooling tower for heat dissipation; when insufficient waste heat causes a drop in the user's water supply temperature, the system automatically adjusts the supply of fresh steam from the boiler to supplement the heating. This closed-loop control system precisely adjusts the cooling tower diversion ratio and steam replenishment amount using a PID algorithm, ensuring the system always maintains an optimal thermal balance state, guaranteeing heating stability while maximizing the utilization of waste heat resources.

[0055] In some embodiments of this application, the boiler is connected to the steam source heat pump unit 25, and the generator set is connected to the steam source heat pump unit 25.

[0056] The high-end heat users require a heat pump system to raise the temperature of the hot water in the insulated pool 12 to meet their requirements. The high-level energy source for the heat pump is surplus electricity from the power plant and fresh steam from the boiler.

[0057] Compared with the prior art, the beneficial technical effects of the technical solution provided in this application include:

[0058] This application utilizes the condenser 11 and the insulation pool 12 to recover the waste heat from the generator set, storing and utilizing the low-grade heat energy lost by traditional cooling towers, thereby improving the overall thermal efficiency of the biomass power plant. The system adopts a cascaded utilization method of heat energy, with low-temperature users directly utilizing the waste heat from the insulation pool 12, and the power source and steam source heat pump units 25 respectively improving the heat grade to meet the heating needs of high-temperature users, achieving efficient and graded utilization of energy. The power source or steam source can be generated by the power plant itself, reducing external energy consumption. At the same time, waste heat recovery can reduce fuel costs and effectively alleviate the operating pressure caused by rising fuel prices. In the context of the reduction of electricity price subsidies, this scheme increases non-electricity income through heating, enhancing the economic sustainability of the project.

[0059] Those skilled in the art will understand that the steps, measures, and schemes in the various operations, methods, processes, and procedures discussed in this application can be alternated, modified, rearranged, decomposed, combined, or deleted.

[0060] The specific embodiments described above do not constitute a limitation on the scope of protection of this application. Any other corresponding changes and modifications made based on the technical concept of this application should be included within the scope of protection of the claims of this application.

Claims

1. A device for utilizing waste heat from a biomass power plant cold source, characterized in that, include: The hot-end regulating module includes a condenser and an insulation tank, wherein the condenser is connected to the insulation tank; The cold-end regulation module includes a low-temperature heat user unit, a first high-temperature heat user unit, a second high-temperature heat user unit, an electric source heat pump unit, and a steam source heat pump unit. The multiple low-temperature heat user units are respectively connected to the insulation pool in a loop. The electric source heat pump unit is connected to the insulation pool and the first high-temperature heat user unit respectively. The steam source heat pump unit is connected to the insulation pool and the second high-temperature heat user unit respectively.

2. The biomass power plant cold source waste heat utilization device according to claim 1, characterized in that, The insulated pool includes a pool body and an insulation layer. The pool body has a hollow inner cavity with a rectangular cross-sectional profile. The insulation layer is applied to the inner wall of the pool body.

3. The biomass power plant cold source waste heat utilization device according to claim 2, characterized in that, The heat preservation tank includes a float level controller and a flow regulating valve. The float level controller is installed in the inner cavity of the tank body, and the flow regulating valve is installed in the pipeline between the condenser and the heat preservation tank.

4. The biomass power plant cold source waste heat utilization device according to claim 2, characterized in that, The heat preservation pool includes a temperature sensor, which is disposed in the inner cavity of the pool body.

5. The biomass power plant cold source waste heat utilization device according to claim 1, characterized in that, The low-temperature heat user unit includes multiple plate heat exchanger groups. Each plate heat exchanger group includes a heat source cavity and a terminal cavity. The heat source cavity covers the terminal cavity. The inlet and outlet of the heat source cavity are both connected to the insulation pool.

6. The biomass power plant cold source waste heat utilization device according to claim 5, characterized in that, The low-temperature heat user unit includes a heating pipe network and a drying equipment, and the terminal chamber of the plate heat exchanger group is connected to the heating pipe network and the drying equipment respectively.

7. The biomass power plant cold source waste heat utilization device according to claim 5, characterized in that, The low-temperature heat user unit includes an inlet water main pipe and a return water main pipe, and multiple plate heat exchanger groups are connected in parallel to each other and are all connected to the inlet water main pipe and the return water main pipe.

8. The biomass power plant cold source waste heat utilization device according to claim 5, characterized in that, The low-temperature heat user unit includes a filter screen, which is disposed in the pipe between the outlet of the heat source cavity and the heat preservation pool.

9. A heating system, characterized in that, It includes a boiler, a generator set, and a waste heat utilization device for a biomass power plant cold source as described in any one of claims 1 to 8, wherein the boiler is connected to the generator set, and the generator set is connected to the condenser.

10. The heating system according to claim 9, characterized in that, The boiler is connected to the steam source heat pump unit, and the generator set is connected to the steam source heat pump unit.

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