A multi-stage waste heat utilization device for distributed energy from gas-fired internal combustion engines

Abstract

This utility model discloses a multi-stage waste heat utilization device for distributed energy from a gas-fired internal combustion engine, relating to the field of energy utilization technology. The utility model includes: a gas-fired internal combustion engine generator set for combustion power generation and equipped with a cylinder-liner water-platform radiator; an intake treatment system, sequentially comprising a gas coarse filter, a gas cooling mechanism, a gas dehydration mechanism, and a gas fine filter along the intake direction, with the outlet end connected to the intake end of the gas-fired internal combustion engine generator set; and an exhaust gas treatment system, sequentially comprising a denitrification injection mechanism and a waste heat boiler along the airflow direction; several gas-fired internal combustion engine generator sets are provided, with each cylinder-liner water-platform radiator's high-temperature pipes flowing separately through a heat exchange section of a high-temperature heat exchange plate; this addresses the problems of waste heat waste, high gas treatment costs, and poor system adaptability in existing technologies.

Description

Technical Field

[0001] This utility model relates to the field of energy utilization technology, specifically, to a multi-stage waste heat utilization device for distributed energy from a gas internal combustion engine. Background Technology

[0002] In industries such as metallurgy and chemicals, combustible waste gases (such as converter gas) are generated during production processes. Traditionally, these waste gases are centrally recovered and utilized through large-scale gas-fired power plants. However, due to factors such as iterative production processes and product structure adjustments, in practice, a small amount of surplus combustion waste gas is often directly released, resulting in underutilization of energy resources. Simultaneously, some enterprises have emergency peak-shaving power generation needs during peak electricity consumption periods, and remote areas outside the grid coverage face challenges in maintaining a stable power supply. These scenarios place higher demands on efficient local energy utilization, flexible system response, environmental friendliness, and cost control, making traditional centralized energy systems inadequate for these needs.

[0003] Reciprocating piston internal combustion engines, with their small size, light weight, high thermal efficiency (up to 38% or more), quick start-up, and ease of mobility, possess natural advantages in distributed power generation scenarios. Different rated power internal combustion engines can be selected to form a generator group based on fuel quantity, calorific value, and required electricity, flexibly responding to peak-shaving demands. However, existing energy systems based on gas-fired internal combustion engines still have significant shortcomings in terms of energy cascade utilization and optimization. First, the efficiency of flue gas waste heat utilization is low. The flue gas emitted by gas-fired internal combustion engines reaches temperatures as high as 500-550℃, containing a large amount of heat energy. Existing technologies mostly adopt a heat exchange mode of single unit equipped with a small boiler, which can only produce low-parameter saturated steam, with limited energy recovery value. Moreover, when multiple units are running in parallel, the flue gas is not centrally integrated for treatment, and it is impossible to generate high-parameter steam or hot water through a unified boiler. This not only increases equipment investment but also causes a large waste of high-temperature flue gas heat energy, failing to achieve large-scale and efficient waste heat recovery.

[0004] Secondly, the cooling system suffers from significant heat energy waste. The cooling system of a gas-fired internal combustion engine includes a cylinder liner water system and an intercooler water system. The cylinder liner water system is a closed-loop system with a circulation volume of 92 m³ / h and a water temperature maintained at 85 / 78℃, carrying a considerable amount of heat energy. However, in the current design, both this system and the intercooler water system (circulation volume 120 m³ / h, water temperature 49 / 45℃) are connected to the water-air radiator on the container roof via a cooling water pump and an electric three-way regulating valve, directly discharging the heat into the atmosphere. The high-temperature heat energy of the cylinder liner water is not recovered and utilized, creating a bottleneck in energy consumption.

[0005] Third, the gas treatment and cooling solutions are unreasonable. As a positive displacement combustion device, the gas internal combustion engine has strict requirements for intake conditions: on the one hand, the intake temperature needs to be below 30°C, and existing cooling methods mostly use electric refrigeration units (which rely on electric motors and consume additional electrical energy) or lithium bromide units (which are driven by thermal energy, but do not combine with the system's own waste heat and still require external energy supplementation); on the other hand, the intake particle size needs to be less than 10μm, and existing filtration solutions are mostly single-stage treatments, which make it difficult to achieve high-precision filtration while ensuring minimal gas resistance loss, thus affecting the unit's operational safety and increasing energy consumption costs. Utility Model Content

[0006] The purpose of this invention is to provide a multi-stage waste heat utilization device for distributed energy of gas internal combustion engines, so as to solve the problems of waste heat waste, high gas treatment cost and poor system adaptability in the prior art.

[0007] To solve the above problems, the present invention adopts the following technical means: A multi-stage waste heat utilization device for distributed energy from a gas-fired internal combustion engine includes: A gas-fired internal combustion engine generator set, used for combustion power generation and equipped with a cylinder-liner water-platform radiator; The intake treatment system comprises, in sequence along the intake direction, a coarse gas filter, a gas cooling mechanism, a gas dehydration mechanism, and a fine gas filter, with the outlet end connected to the intake end of the gas internal combustion engine generator set. The exhaust gas treatment system consists of a denitrification injection mechanism and a waste heat boiler arranged sequentially along the airflow direction. The gas internal combustion engine generator set is provided with several units. The high-temperature pipe of each cylinder liner water platform radiator flows separately through the heat exchange section of a high-temperature heat exchange plate. The inlet / outlet liquid direction of the heating end of the high-temperature heat exchange plate is connected to the first end of the hot water type lithium bromide refrigeration unit, and the inlet / outlet liquid end of the gas cooling mechanism is connected to the second end of the hot water type lithium bromide refrigeration unit.

[0008] Preferably, the air intake treatment system includes a main gas pipe and gas branch pipes. The gas coarse filter, gas cooling, gas dehydration and gas fine filter are sequentially installed on the main gas pipe. The gas branch pipes serve as the gas outlet and are connected to the downstream side of the gas filtration mechanism. A plurality of gas branch pipes are connected to the main gas pipe, and each gas branch pipe is connected to the gas consumption end of a gas internal combustion engine generator set.

[0009] Furthermore, the exhaust gas treatment system includes a main flue gas pipe and flue gas branch pipes. Each flue gas branch pipe is connected to the exhaust end of the gas internal combustion engine generator set, and the end of each flue gas branch pipe is connected to the main flue gas pipe. The denitrification injection mechanism and the waste heat boiler are sequentially connected to the downstream section of the main flue gas pipe relative to the flue gas branch pipe.

[0010] Furthermore, the waste heat boiler is constructed sequentially along the airflow direction, including a superheater, a thermostat, a denitrification section, an evaporator, an economizer, and a condensate heater. The flue gas finally passes through the condensate heater and then through the chimney of the waste heat boiler.

[0011] Furthermore, the high-temperature pipes of the cylinder liner water-cooled radiator serve as the cold end of the high-temperature heat exchange plate, and the internal temperature of the high-temperature pipes is reduced after passing through the high-temperature heat exchange plate. The first end of the hot water type lithium bromide chiller is connected to a circulation pipe, which passes through the hot end of the high-temperature heat exchange plate, and the temperature inside the circulation pipe is raised after passing through the high-temperature heat exchange plate.

[0012] Furthermore, the heating ends of several of the high-temperature heat exchange plates are connected in parallel to the circulation pipe.

[0013] This utility model has the following beneficial effects during use: For scenarios involving limited natural gas surplus for local utilization, power generation applications with peak-shaving requirements, or power supply needs in remote areas not covered by the power grid, distributed gas-fired power generation systems can be constructed using gas-fired internal combustion engine groups. These systems not only have short construction cycles, flexible start-up and shutdown, and high safety and reliability, but also reduce investment in power transmission and distribution, solving power supply problems in remote areas. Furthermore, they are compact in structure, occupy a small area, are easy to deploy, and have a simple control system.

[0014] For the high-temperature flue gas emitted after the combustion of internal combustion engines, steam is generated by heat exchange in a boiler, which can be used for production, heating or steam turbines. This fully utilizes the energy cascade and greatly improves the overall energy utilization efficiency of the system.

[0015] By utilizing the heat from the high-temperature cylinder liner water in an internal combustion engine and employing a lithium bromide chiller to cool the water, the temperature of the combustion gas can be controlled within the required range. This eliminates the need for excess energy, reduces losses in intermediate stages, and maximizes and optimizes energy and resource utilization. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of this utility model.

[0017] Among them, 1-gas internal combustion engine generator set, 2-gas coarse filter mechanism, 3-gas cooling mechanism, 4-gas dehydration mechanism, 5-gas fine filter mechanism, 6-high temperature heat exchange plate, 7-gas main pipe, 8-gas branch pipe, 9-hot water type lithium bromide refrigeration unit, 10-collecting flue gas pipe, 11-cylinder liner water platform radiator, 12-flue gas branch pipe, 13-denitrification injection mechanism, 14-superheater, 15-thermal controller, 16-denitrification section, 17-waste heat boiler, 18-circulation pipe, 19-evaporator, 20-economizer, 21-condensate heater. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can typically be arranged and designed in various different configurations.

[0019] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0020] It should be noted that, where there is no conflict, the embodiments and features in the embodiments of this utility model can be combined with each other.

[0021] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0022] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this utility model is in use, or the orientation or positional relationship commonly understood by those skilled in the art. They are only used for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first," "second," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0023] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0024] Please refer to Figure 1 As shown, a multi-stage waste heat utilization device for distributed energy from a gas-fired internal combustion engine includes: A gas-fired internal combustion engine generator set 1 is used for combustion power generation and is equipped with a cylinder-liner water-platform radiator 11. The intake treatment system includes a gas coarse filter 2, a gas cooling mechanism 3, a gas dehydration mechanism 4, and a gas fine filter 5 arranged sequentially along the intake direction. The outlet end is connected to the intake end of the gas internal combustion engine generator set 1. The exhaust gas treatment system includes a denitrification injection mechanism 13 and a waste heat boiler 17 arranged sequentially along the airflow direction. The gas internal combustion engine generator set 1 is provided with several units. The high-temperature pipe of each cylinder liner water platform radiator 11 flows separately through the heat exchange section of a high-temperature heat exchange plate 6. The inlet / outlet liquid direction of the heating end of the high-temperature heat exchange plate 6 is connected to the first end of the hot water type lithium bromide refrigeration unit 9, and the inlet / outlet liquid end of the gas cooling mechanism 3 is connected to the second end of the hot water type lithium bromide refrigeration unit 9.

[0025] Preferably, the air intake treatment system includes a main gas pipe 7 and gas branch pipes 8. The gas coarse filter mechanism 2, the gas cooling mechanism 3, the gas dehydration mechanism 4, and the gas fine filter mechanism 5 are sequentially installed on the main gas pipe 7. The gas branch pipes 8 serve as the gas outlet and are connected to the downstream side of the gas filtration mechanism. A plurality of gas branch pipes 8 are connected to the main gas pipe 7, and each gas branch pipe 8 is connected to the gas consumption end of a gas internal combustion engine generator set 1.

[0026] Furthermore, the exhaust gas treatment system includes a main flue gas pipe 10 and flue gas branch pipes 12. Each flue gas branch pipe 12 is connected to the exhaust end of the gas internal combustion engine generator set 1, and the end of each flue gas branch pipe 12 is connected to the main flue gas pipe 10. The denitrification injection mechanism 13 and the waste heat boiler 17 are sequentially connected to the downstream section of the main flue gas pipe 10 relative to the flue gas branch pipes 12.

[0027] Furthermore, the waste heat boiler 17 is constructed in sequence along the airflow direction, including a superheater 14, a thermostat 15, a denitrification section 16, an evaporator 19, an economizer 20, and a condensate heater 21. The flue gas finally passes through the condensate heater 21 and then through the chimney of the waste heat boiler 17.

[0028] Furthermore, the high-temperature pipes of the cylinder liner water-type radiator 11 serve as the cold end of the high-temperature heat exchange plate 6, and the internal temperature of the high-temperature pipes is reduced after passing through the high-temperature heat exchange plate 6. The first end of the hot water type lithium bromide refrigeration unit 9 is connected to a circulation pipe 18. The circulation pipe 18 passes through the hot end of the high temperature heat exchange plate 6, and the temperature inside the circulation pipe 18 is raised after passing through the high temperature heat exchange plate 6.

[0029] Furthermore, the heating ends of several of the high-temperature heat exchange plates 6 are connected in parallel to the circulation pipe 18.

[0030] The converter gas first enters the coarse gas filtration unit 2, where large particles and a small amount of water are removed by filtering through a filter screen. The coarse filter accuracy is required to be <100μm. Then, the high-temperature gas enters the gas cooling unit 3, where a chilled water pump sends chilled water to the gas cooling unit 3 to exchange heat with the gas. The gas temperature drops from 60℃ to 30℃, while the chilled water temperature rises from 16℃ to 23℃. Then, the low-temperature gas enters the gas dehydration unit 4. The gas enters from the bottom and exits from the top of the gas-liquid separator. Water droplets collide with the wall of the dehydrator under centrifugal force, causing the water droplets to lose kinetic energy and separate from the gas flow, thus achieving the purpose of dust removal and separation of free water. Subsequently, the gas enters the fine gas filtration unit 5, where most of the particles and a small amount of water are removed by a filter screen. The fine filter accuracy is required to be <5μm to meet the safe operation requirements of the unit.

[0031] The flue gas emitted after combustion from each gas-fired internal combustion engine generator set 1 is collected into a main flue gas pipe 10 through various flue gas branch pipes 12. A denitrification injection mechanism 13 installed on the main flue gas pipe 10 injects vaporized ammonia water into the flue gas. After reacting in the flue for a period of time, the flue gas enters the waste heat boiler 17. The flue gas first passes through the superheater 14 and thermostat 15, where the temperature is reduced from 500℃ to 350℃ through heat exchange with steam. The flue gas then enters the denitrification section 16, where it reacts fully with the denitrification catalyst. Finally, the flue gas passes sequentially through the evaporator 19, economizer 20, and condensate heater 21, reducing its temperature to 130℃ before being discharged into the atmosphere through the chimney. The deoxygenated boiler feedwater at 104℃, after heat exchange with the flue gas in the waste heat boiler 17, can generate superheated steam at 1.6 MPa (A), 360℃, and 9 t / h for subsequent production.

[0032] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A multi-stage waste heat utilization device for distributed energy from a gas-fired internal combustion engine, characterized in that, include: A gas-fired internal combustion engine generator set (1) is used for combustion power generation and is equipped with a cylinder-liner water-platform radiator (11). The intake treatment system is constructed in sequence along the intake direction, including a gas coarse filter mechanism (2), a gas cooling mechanism (3), a gas dehydration mechanism (4), and a gas fine filter mechanism (5), with the outlet end connected to the intake end of the gas internal combustion engine generator set (1). The exhaust gas treatment system is constructed in sequence along the airflow direction, including a denitrification injection mechanism (13) and a waste heat boiler (17). The gas internal combustion engine generator set (1) is provided with several units. The high temperature pipeline of each cylinder liner water platform radiator (11) flows separately through the heat exchange section of a high temperature heat exchange plate (6). The inlet / outlet liquid direction of the heating end of the high temperature heat exchange plate (6) is connected to the first end of the hot water type lithium bromide refrigeration unit (9). The inlet / outlet liquid end of the gas cooling mechanism (3) is connected to the second end of the hot water type lithium bromide refrigeration unit (9).

2. The multi-stage waste heat utilization device for distributed energy from a gas-fired internal combustion engine according to claim 1, characterized in that, The intake treatment system includes a gas main pipe (7) and gas branch pipes (8). The gas coarse filter (2), gas cooling mechanism (3), gas dehydration mechanism (4) and gas fine filter (5) are installed sequentially on the gas main pipe (7). The gas branch pipes (8) serve as the gas outlet and are connected to the downstream side of the gas filtration mechanism. Several gas branch pipes (8) are connected to the gas main pipe (7). Each gas branch pipe (8) is connected to the gas consumption end of a gas internal combustion engine generator set (1).

3. The multi-stage waste heat utilization device for distributed energy from a gas-fired internal combustion engine according to claim 1, characterized in that, The exhaust gas treatment system includes a main flue gas pipe (10) and flue gas branch pipes (12). Each flue gas branch pipe (12) is connected to the exhaust end of the gas internal combustion engine generator set (1), and the end of each flue gas branch pipe (12) is connected to the main flue gas pipe (10). The denitrification injection mechanism (13) and the waste heat boiler (17) are connected in sequence to the downstream section of the main flue gas pipe (10) relative to the flue gas branch pipes (12).

4. A multi-stage waste heat utilization device for distributed energy from a gas-fired internal combustion engine according to claim 1 or 3, characterized in that, The waste heat boiler (17) is constructed in sequence along the airflow direction, including a superheater (14), a thermostat (15), a denitrification section (16), an evaporator (19), an economizer (20), and a condensate heater (21). The flue gas finally passes through the condensate heater (21) and then through the chimney of the waste heat boiler (17).

5. A multi-stage waste heat utilization device for distributed energy from a gas-fired internal combustion engine according to claim 1, characterized in that, The high-temperature pipeline of the cylinder liner water-type radiator (11) serves as the cold end of the high-temperature heat exchange plate (6). After the high-temperature pipeline passes through the high-temperature heat exchange plate (6), the internal temperature is reduced. The first end of the hot water type lithium bromide refrigeration unit (9) is connected to a circulation pipe (18). The circulation pipe (18) passes through the hot end of the high temperature heat exchange plate (6), and the temperature inside the circulation pipe (18) is raised after passing through the high temperature heat exchange plate (6).

6. A multi-stage waste heat utilization device for distributed energy from a gas-fired internal combustion engine according to claim 5, characterized in that, The heating ends of several of the high-temperature heat exchange plates (6) are connected in parallel to the circulation pipe (18).

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