CN205936722U - Waste heat multistage utilization's distributed energy power generation system - Google Patents

Abstract

The utility model relates to a distributed energy generation system for multi-stage utilization of waste heat. Distributed energy systems have high gas prices and low efficiency of waste heat utilization systems. The distributed energy power generation system of the utility model includes a gas-fired internal combustion engine generator set, a waste heat boiler and a steam-type lithium bromide unit, and is characterized in that it also includes a multi-stage organic Rankine cycle system, and the multi-stage organic Rankine cycle system includes a No. 1 regenerator , No. 1 evaporator, No. 2 regenerator, preheater, No. 3 expander, No. 3 condenser and steam-hot water heat exchanger, No. 1 working fluid pump, No. 1 regenerator, and No. 1 evaporator Connect with No. 1 expander in turn, No. 1 expander and No. 1 regenerator, No. 2 working fluid pump, No. 2 regenerator, preheater, No. 2 evaporator, No. 2 expander and No. 2 condenser Connected in sequence, No. 3 regenerator, No. 3 evaporator, No. 3 expander and No. 3 condenser are connected in sequence. The utility model has reasonable structural design and high thermal efficiency.

Description

A distributed energy generation system with multi-level utilization of waste heat

technical field

The utility model relates to a distributed energy generation system for multi-stage utilization of waste heat, which belongs to the technical field of energy utilization.

Background technique

Distributed energy is an energy supply method built on the user side. It can operate independently or in parallel with the grid. It is a system that determines the mode and capacity by maximizing resources and environmental benefits. According to various energy needs of users and resource allocation System integration and optimization according to the situation, the new energy system adopting demand-responsive design and modular configuration is a decentralized energy supply method relative to centralized energy supply.

Distributed energy has the characteristics of high efficiency, energy saving, and environmental protection, which promotes the purpose of low carbon emissions. Distributed energy has received more and more attention. There are also some problems in the distributed energy system. At present, the national policy related to natural gas distributed energy is not clear, the gas price is high, and the efficiency of the waste heat utilization system does not have an advantage compared with the gas boiler. In this case, it can be effectively It is the key to the development of distributed energy to improve the efficiency of distributed energy by using the waste heat of distributed energy system. There are also some distributed energy utilization systems of other structures, such as the Chinese patent whose publication date is July 24, 2013, and the publication number is CN203081665U, a distributed multi-stage solar thermal power generation system disclosed, and the publication date is On January 16, 2013, the Chinese patent with the publication number CN102878035A disclosed a multi-level solar energy and other energy complementary thermal power generation and polygeneration system. The thermal efficiency of these distributed energy utilization systems is not high.

Utility model content

The purpose of the utility model is to overcome the above-mentioned deficiencies in the prior art, and provide a distributed energy generation system with reasonable structure design, high thermal efficiency and multi-stage utilization of waste heat.

The technical scheme adopted by the utility model to solve the above problems is: the distributed energy power generation system for multi-stage utilization of waste heat includes a gas-fired internal combustion engine generator set, a waste heat boiler and a steam-type lithium bromide The lithium bromide unit is connected in sequence, and its structural feature is that it also includes a multi-stage organic Rankine cycle system. The multi-stage organic Rankine cycle system includes the No. 1 working fluid pump, the No. 1 regenerator, the No. machine, No. 1 condenser, No. 2 working fluid pump, No. 2 regenerator, preheater, No. 2 evaporator, No. 2 expander, No. 2 condenser, No. 3 working fluid pump, No. 3 regenerator, The No. 3 evaporator, the No. 3 expander, the No. 3 condenser and the steam-hot water heat exchanger, the No. 1 working fluid pump, the No. 1 regenerator, the No. 1 evaporator and the No. 1 expander are connected in sequence. The No. 1 expander is connected to the No. 1 regenerator, the No. 1 condenser is connected to the No. 1 regenerator, the No. 1 evaporator is connected to the gas internal combustion engine generator set, and the No. 2 working medium pump, No. 2 The regenerator, preheater, No. 2 evaporator, No. 2 expander and No. 2 condenser are connected sequentially. The steam type lithium bromide unit and the No. 1 evaporator are connected to the No. 2 evaporator, and the No. 3 working fluid The pump, the No. 3 regenerator, the No. 3 evaporator, the No. 3 expander and the No. 3 condenser are connected in sequence, and the waste heat boiler, the steam-hot water type heat exchanger and the No. 3 evaporator are connected in sequence.

As a preference, the No. 3 evaporator of the utility model is connected to the gas internal combustion engine generator set.

A distributed energy generation method using the distributed energy generation system for multi-stage utilization of waste heat, characterized in that: the steps of the distributed energy generation method are as follows:

The gas-fired internal combustion engine generator set uses natural gas as fuel to drive the engine to generate electricity, and the exhausted flue gas first enters the waste heat boiler to generate steam to drive the steam-type lithium bromide unit, heating in winter and cooling in summer;

The circulating working fluid in the first-level organic Rankine cycle is pressurized by the No. 1 working fluid pump and then enters the No. 1 regenerator to be heated, and then enters the No. 1 evaporator to be gasified into steam, and then drives the No. 1 expander to generate electricity. At the same time, the gas internal combustion engine generates electricity. The flue gas discharged from the unit is used as the heat source of the No. 1 evaporator, and the exhaust steam enters the No. 1 condenser to complete the power generation of the first-order organic Rankine cycle;

The circulating working fluid in the secondary organic Rankine cycle is pressurized by the No. 2 working fluid pump and then enters the No. 2 regenerator for heating, then enters the preheater and enters the No. 2 evaporator to be gasified into steam, and then drives the No. 2 expander to generate electricity , at the same time, the No. 1 evaporator is used as the heat source of the No. 2 evaporator, and the exhaust steam enters the No. 2 condenser to complete the power generation of the second organic Rankine cycle;

The circulating working fluid in the three-stage organic Rankine cycle is pressurized by the No. 3 working fluid pump, then enters the No. 3 regenerator for heating, and then enters the No. 3 evaporator to be gasified into steam, and then drives the No. 3 expander to generate electricity. At the same time, the waste heat boiler generates The steam passed through the steam-hot water heat exchanger is used as the heat source of the No. 3 evaporator, and the exhaust steam enters the No. 3 condenser to complete the power generation of the three-stage organic Rankine cycle.

As a preference, the distributed energy power generation system for multi-stage utilization of waste heat described in the present invention has a three-stage organic Rankine cycle, and the heat sources of the three-stage organic Rankine cycle are respectively flue gas, steam and water.

As preferably, the organic working medium of the utility model should be a dry working medium.

As a preference, the gas-fired internal-combustion engine generator set of the utility model discharges at a temperature of 410°C. After passing through the waste heat boiler, the temperature of the flue gas drops to 130°C, which is used as a heat source for the organic working medium; the temperature of the cylinder jacket water is 89°C. The cooling water passes through the heat exchange with steam. Then it becomes 130°C, which is used as the heat source of the second-stage organic Rankine cycle; the hot water with a steam temperature of 50°C at the outlet of the steam-type lithium bromide unit is used as the heat source of the third-stage organic Rankine cycle after being heated by flue gas.

As a preference, the first-stage organic Rankine cycle, the second-stage organic Rankine cycle and the third-stage organic Rankine cycle of the utility model all use R245fa as the circulating working fluid.

Compared with the prior art, the utility model has the following advantages and effects: using natural gas as the fuel of the internal combustion engine, it has the advantages of clean discharge, the waste heat utilization system adopts waste heat boiler and steam type lithium bromide unit, and introduces a three-stage organic Rankine cycle at the same time, The temperature of the gas-fired internal combustion engine is 410°C. After the flue gas passes through the waste heat boiler, the temperature drops to 130°C. As a heat source for the organic working medium, the temperature of the cylinder jacket water is 89°C. After heat exchange with steam, the cooling water becomes 130°C. The heat source of the second-stage organic Rankine cycle, the hot water with a steam temperature of 50 °C at the outlet of the steam-type lithium bromide unit is used as the heat source of the third-stage organic Rankine cycle after being heated by flue gas. The utility model has the advantage of introducing three organic Rankine cycles into the distributed energy system, which can increase the net output power, reduce the fuel consumption rate of the gas internal combustion engine, and improve the thermal efficiency of the distributed energy system.

Description of drawings

Fig. 1 is a schematic structural diagram of a distributed energy generation system for multi-stage utilization of waste heat in an embodiment of the utility model.

In the figure: 1-gas internal combustion engine generator set; 2-waste heat boiler; 3-steam-type lithium bromide unit; 4-No. 1 working medium pump; 5-No. 1 regenerator; 6-No. 1 evaporator; 7-No. 1 expansion 8- No. 1 condenser; 9- No. 2 working fluid pump; 10- No. 2 regenerator; 11- Preheater; 12- No. 2 evaporator; 13- No. 2 expander; 14- No. 2 condensation 15-No. 3 working fluid pump; 16-No. 3 regenerator; 17-No. 3 evaporator; 18-No. 3 expander; 19-No. 3 condenser; 20-steam hot water heat exchanger.

detailed description

The utility model will be further described in detail below in conjunction with the accompanying drawings and examples. The following examples are explanations of the utility model and the utility model is not limited to the following examples.

Example.

Referring to Fig. 1, the distributed energy power generation system for multi-stage utilization of waste heat in this embodiment includes a gas-fired internal combustion engine generator set 1, a waste heat boiler 2, a steam-type lithium bromide set 3 and a multi-stage organic Rankine cycle system.

In this embodiment, the gas-fired internal combustion engine generator set 1, the waste heat boiler 2 and the steam-type lithium bromide unit 3 are connected in sequence, and the multi-stage organic Rankine cycle system includes No. 1 working fluid pump 4, No. 1 regenerator 5, and No. 1 evaporator 6 , No. 1 expander 7, No. 1 condenser 8, No. 2 working medium pump 9, No. 2 regenerator 10, preheater 11, No. 2 evaporator 12, No. 2 expander 13, No. 2 condenser 14, No. 3 working fluid pump 15, No. 3 regenerator 16, No. 3 evaporator 17, No. 3 expander 18, No. 3 condenser 19 and steam hot water heat exchanger 20, No. 1 working fluid pump 4, No. 1 The regenerator 5, the No. 1 evaporator 6 and the No. 1 expander 7 are connected in sequence, the No. 1 expander 7 is connected to the No. 1 regenerator 5, the No. 1 condenser 8 is connected to the No. 1 regenerator 5, and the No. 1 evaporator The device 6 is connected to the gas-fired internal combustion engine generator set 1, the No. 2 working fluid pump 9, the No. 2 regenerator 10, the preheater 11, the No. 2 evaporator 12, the No. 2 expander 13 and the No. 2 condenser 14 are connected in sequence, and the steam Type lithium bromide unit 3 and No. 1 evaporator 6 are all connected to No. 2 evaporator 12, No. 3 working fluid pump 15, No. 3 regenerator 16, No. 3 evaporator 17, No. 3 expander 18 and No. 3 condenser 19 They are connected in sequence, and the waste heat boiler 2, the steam-hot water heat exchanger 20 and the No. 3 evaporator 17 are connected in sequence.

The No. 3 evaporator 17 in this embodiment is connected to the gas internal combustion engine generator set 1 . There should be a regenerator before exhaust steam at the outlet of the expander enters the condenser.

In this embodiment, the steps of the distributed energy generation method performed by using the distributed energy generation system for multi-stage utilization of waste heat are as follows.

The gas-fired internal combustion engine generator set 1 uses natural gas as fuel to drive the engine to generate electricity, and the exhausted flue gas first enters the waste heat boiler 2 to generate steam to drive the steam-type lithium bromide unit 3, heating in winter and cooling in summer.

The circulating working fluid in the first-level organic Rankine cycle is pressurized by the No. 1 working fluid pump 4, then enters the No. 1 regenerator 5 for heating, and then enters the No. 1 evaporator 6 to be gasified into steam, and then drives the No. 1 expander 7 to generate electricity. At the same time, the flue gas discharged from the gas internal combustion engine generator set 1 is used as the heat source of the No. 1 evaporator 6, and the exhaust gas enters the No. 1 condenser 8 to complete the power generation of the first-order organic Rankine cycle.

The circulating working fluid in the secondary organic Rankine cycle is pressurized by the No. 2 working fluid pump 9 and then enters the No. 2 regenerator 10 for heating, then enters the preheater 11 and then enters the No. 2 evaporator 12 to be vaporized to drive the second The No. 1 expander 13 generates power, and the No. 1 evaporator 6 is used as the heat source of the No. 2 evaporator 12, and the exhaust steam enters the No. 2 condenser 14 to complete the power generation of the second-stage organic Rankine cycle.

The circulating working fluid in the three-stage organic Rankine cycle is pressurized by the No. 3 working fluid pump 15, then enters the No. 3 regenerator 16 for heating, and then enters the No. 3 evaporator 17 to be gasified into steam, and then drives the No. 3 expander 18 to generate electricity. At the same time, the steam generated by the waste heat boiler 2 passes through the steam-hot water heat exchanger 20 as the heat source of the No. 3 evaporator 17, and the exhaust steam enters the No. 3 condenser 19 to complete the power generation of the three-stage organic Rankine cycle.

In this embodiment, the distributed energy power generation system with multi-stage utilization of waste heat has a three-stage organic Rankine cycle, and the heat sources of the three-stage organic Rankine cycle are flue gas, steam and water respectively. Organic working fluid should be dry working fluid. The primary organic Rankine cycle, the secondary organic Rankine cycle and the tertiary organic Rankine cycle all use R245fa as the circulating working fluid.

The gas-fired internal combustion engine generator set 1 in this embodiment discharges at a temperature of 410°C, and the temperature of the flue gas drops to 130°C after passing through the waste heat boiler 2, which is used as a heat source for the organic working fluid; the temperature of the cylinder jacket water is 89°C, and the cooling water is exchanged with steam. After heating, it becomes 130°C, which is used as the heat source of the second-stage organic Rankine cycle; the hot water with a steam temperature of 50°C at outlet 3 of the steam-type lithium bromide unit is used as the heat source of the third-stage organic Rankine cycle after being heated by flue gas .

In addition, it should be noted that the specific embodiments described in this specification may be different in parts, shapes and names of parts, and the above content described in this specification is only an illustration of the structure of the present invention. All equivalent changes or simple changes based on the structure, features and principles described in the utility model patent concept are included in the protection scope of the utility model patent. Those skilled in the technical field to which the utility model belongs can make various modifications or supplements to the described specific embodiments or adopt similar methods to replace them, as long as they do not deviate from the structure of the utility model or exceed the definition defined in the claims scope, all should belong to the protection scope of the present utility model.

Claims (2)

1. A distributed energy power generation system for multi-stage utilization of waste heat, including a gas-fired internal combustion engine generator set (1), a waste heat boiler (2) and a steam-type lithium bromide unit (3), the gas-fired internal combustion engine generator set (1), waste heat boiler (2) is sequentially connected with the steam type lithium bromide unit (3), and is characterized in that it also includes a multi-stage organic Rankine cycle system, and the multi-stage organic Rankine cycle system includes No. 1 working fluid pump (4), No. 1 return Heater (5), No. 1 evaporator (6), No. 1 expander (7), No. 1 condenser (8), No. 2 working fluid pump (9), No. 2 regenerator (10), preheating No. 2 evaporator (11), No. 2 evaporator (12), No. 2 expander (13), No. 2 condenser (14), No. 3 working fluid pump (15), No. 3 regenerator (16), and No. 3 evaporator (17), No. 3 expander (18), No. 3 condenser (19) and steam hot water heat exchanger (20), the No. 1 working fluid pump (4), No. 1 regenerator (5 ), the No. 1 evaporator (6) and the No. 1 expander (7) are connected sequentially, the No. 1 expander (7) is connected to the No. 1 regenerator (5), and the No. 1 condenser (8) and The No. 1 regenerator (5) is connected, the No. 1 evaporator (6) is connected to the gas internal combustion engine generator set (1), the No. 2 working fluid pump (9), the No. 2 regenerator (10), the preheater Heater (11), No. 2 evaporator (12), No. 2 expander (13) and No. 2 condenser (14) are connected sequentially, and the steam type lithium bromide unit (3) and No. 1 evaporator (6) are both Connected with the No. 2 evaporator (12), the No. 3 working fluid pump (15), No. 3 regenerator (16), No. 3 evaporator (17), No. 3 expander (18) and No. 3 condenser (19) are connected in sequence, and the waste heat boiler (2), the steam-hot water heat exchanger (20) and the No. 3 evaporator (17) are connected in sequence. 2. The distributed energy generation system for multi-stage utilization of waste heat according to claim 1, characterized in that: the No. 3 evaporator (17) is connected to a gas-fired internal combustion engine generator set (1).