Normal-pressure expansion turbine power generation system, power generation method and application

Abstract

The invention provides a normal-pressure expansion turbine power generation system, and belongs to the technical field of waste heat utilization. The system comprises a normal-pressure expansion turbine, a generator and a compressor which are coaxially arranged; the generator is located between the normal-pressure expansion turbine and the compressor, and the normal-pressure expansion turbine drives the generator and the compressor to rotate; a normal-pressure expansion turbine exhaust port of the normal-pressure expansion turbine is communicated with a compressor air inlet of the compressor through a pipeline; high-temperature and normal-pressure gas enters from a normal-pressure expansion turbine gas inlet of the normal-pressure expansion turbine to drive turbine blades of the normal-pressure expansion turbine to do work, then the generator is driven to do work to generate electricity, the normal-pressure expansion turbine drives the compressor to rotate to provide vacuum for the normal-pressure expansion turbine, and exhaust gas of the normal-pressure expansion turbine enters the compressor after being cooled. Energy of high-temperature normal-pressure gas can be efficiently converted, so that energy loss is reduced, and the energy conversion device becomes an ideal choice for high-temperature waste gas and waste heat energy conversion.

Description

Technical Field

[0001] The present invention relates to the technical field of waste heat utilization, and in particular to a normal pressure expansion turbine power generation system, a method for generating electricity by using high temperature normal pressure gas, and the application of the power generation system in industrial waste heat recovery and utilization. Background Art

[0002] The original micro gas turbine was a scaled-down version of a conventional gas turbine, mainly used for aviation and military purposes. Due to technical limitations, early micro gas turbines were inefficient and had poor reliability. With the advancement of materials science, computational fluid dynamics, and combustion technology, micro gas turbines have made significant progress in efficiency and durability. In particular, the application of high-temperature materials and advanced coating technology has enabled turbines to operate at higher temperatures. The working principle of a micro gas turbine is similar to that of a conventional gas turbine, and energy conversion is completed mainly through the following steps:

[0003] Air compression: Air is compressed by a compressor (usually a centrifugal or axial flow compressor), increasing the pressure and temperature;

[0004] Combustion: The compressed high-pressure air enters the combustion chamber and mixes with fuel (such as natural gas, diesel, etc.) to burn, producing high-temperature and high-pressure gas;

[0005] Turbine drive: High-temperature and high-pressure gas drives the turbine to rotate. The turbine is coaxially connected with the compressor, and the turbine drives the compressor to work;

[0006] Power generation: The rotation of the turbine also drives the generator to generate electricity, converting mechanical energy into electrical energy.

[0007] Micro gas turbines have begun to be widely used in the fields of distributed energy, backup power supply and mobile power supply. Modern micro gas turbines have the advantages of fast startup and easy maintenance, and are gradually accepted by the market. Although the existing technology involves the efficient utilization of micro gas turbines, micro gas turbines drive the turbine through high-pressure compression and high-temperature combustion, and the working fluid is generally high-temperature pressurized gas. This places strict requirements on the design, material selection and manufacturing process of the system. However, in many waste heat utilization scenarios, the heat of high-temperature and normal-pressure gas is difficult to be fully utilized, resulting in a large amount of energy waste, which is not conducive to improving the overall energy efficiency of the system. Summary of the invention

[0008] In view of this, in order to solve the technical problem that the heat of high-temperature and normal-pressure gas in the prior art is difficult to be fully utilized, resulting in a large amount of energy waste, which is not conducive to improving the overall energy efficiency of the system. In the first aspect, the present invention provides a normal-pressure expansion turbine power generation system, in which high-temperature and normal-pressure gas enters from the air inlet of the normal-pressure expansion turbine, drives the turbine blades to work, and then drives the generator to work and generate electricity. It can efficiently convert the energy of high-temperature and normal-pressure gas, thereby reducing energy loss, and is an ideal choice for high-temperature exhaust gas and waste heat energy conversion.

[0009] To achieve the above object, the present invention provides the following technical solutions:

[0010] A normal pressure expansion turbine power generation system comprises a normal pressure expansion turbine, a generator and a compressor arranged coaxially;

[0011] The generator is located between the atmospheric expansion turbine and the compressor, and the atmospheric expansion turbine drives the generator and the compressor to rotate;

[0012] The atmospheric expansion turbine exhaust port of the atmospheric expansion turbine is connected to the compressor air inlet of the compressor through a pipeline;

[0013] High-temperature normal-pressure gas enters from the air inlet of the normal-pressure expansion turbine, drives the turbine blades of the normal-pressure expansion turbine to work, and then drives the generator to work and generate electricity. The normal-pressure expansion turbine drives the compressor to rotate to provide vacuum for the normal-pressure expansion turbine, and the exhaust gas of the normal-pressure expansion turbine enters the compressor after cooling.

[0014] Preferably, it also includes:

[0015] A cooler is connected between the exhaust port of the atmospheric expansion turbine and the air inlet of the compressor, and is used for cooling the gas discharged through the exhaust port of the atmospheric expansion turbine.

[0016] Preferably, the atmospheric expansion turbine, the generator and the compressor are connected via a rotating shaft.

[0017] Preferably, a turbine outlet diffuser is provided at the exhaust port of the atmospheric expansion turbine.

[0018] Preferably, the compressor is a vacuum compressor.

[0019] In a second aspect, the present invention provides a power generation method of the above-mentioned atmospheric expansion turbine power generation system, comprising the following steps:

[0020] High-temperature normal-pressure gas enters from the air inlet of the normal-pressure expansion turbine, drives the turbine blades to work, and further drives the generator to work and generate electricity;

[0021] The atmospheric expansion turbine is coaxial with the compressor, and the turbine blades drive the compressor to rotate via a rotating shaft to provide vacuum for the atmospheric expansion turbine.

[0022] In a third aspect, the present invention provides the application of the above-mentioned atmospheric expansion turbine power generation system or the above-mentioned power generation method in industrial waste heat recovery and distributed energy.

[0023] The atmospheric expansion turbine power generation system, power generation method and application provided by the present invention can efficiently convert the energy of high-temperature atmospheric pressure gas, thereby reducing energy loss, and become an ideal choice for high-temperature exhaust gas and waste heat energy conversion. Compared with the existing technology, it has the following beneficial effects:

[0024] (1) System simplification and cost reduction

[0025] Existing micro gas turbines: Micro gas turbines rely on high-pressure compression and high-temperature combustion to drive the turbine. The system design is complex and has high requirements for the compressor, combustion chamber and high-temperature materials, resulting in high manufacturing and maintenance costs.

[0026] The atmospheric expansion turbine power generation system and method provided by the present invention does not require a high-pressure compression process for the gas, has a simpler system structure, has lower material requirements, is stable in system operation, and is easier to maintain, which is suitable for long-term reliable operation scenarios. At the same time, it has significant advantages in system design and manufacturing costs, and can significantly reduce manufacturing and maintenance costs. It is suitable for cost-sensitive application scenarios.

[0027] (2) Energy recovery efficiency

[0028] Microturbines: Microturbines have high efficiency at high pressure and temperature, but their efficiency drops significantly at low loads or pressures, and their waste heat recovery potential is limited.

[0029] The atmospheric expansion turbine power generation system and method provided by the present invention are more suitable for processing high-temperature atmospheric pressure exhaust gas in industrial processes, can more effectively recover the energy in these exhaust gases, and have stable efficiency in a wider load range. Especially under low load, the efficiency is more stable than that of micro gas turbines. The present invention has higher energy conversion efficiency under waste heat recovery and low load conditions, and is more suitable for distributed energy and industrial waste heat recovery.

[0030] (3) Wide range of applicable scenarios

[0031] Micro gas turbine: suitable for efficient centralized power generation, mainly used in scenarios requiring high energy density and high output power, but not suitable for low load or low pressure waste heat utilization scenarios.

[0032] The atmospheric expansion turbine power generation system and method provided by the present invention are applicable to various high-temperature atmospheric pressure waste gas recovery and utilization, such as industrial waste heat recovery and utilization, such as distributed power generation, power plant waste heat recovery and utilization, cogeneration of heat and power, etc. It has wider applicability and higher flexibility.

[0033] In summary, the present invention has obvious advantages over micro gas turbines in terms of system simplification, energy recovery efficiency and wide application scenarios. In particular, high temperature and normal pressure technology is more economical, efficient and environmentally friendly in industrial waste heat recovery and distributed energy applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a structural schematic diagram of the present invention;

[0035] In the figure, 1. generator; 2. rotating shaft; 3. air inlet of atmospheric expansion turbine; 4. turbine blades; 5. atmospheric expansion turbine; 6. turbine outlet diffuser; 7. cooler; 8. air inlet of compressor; 9. compressor; 10. compressor blades; 11. compressor diffuser; 12. compressor exhaust. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention; it is obvious that the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments, and all other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making creative work are within the scope of protection of the present invention.

[0037] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "top / bottom" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0038] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "mounted / connected", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] like Figure 1 As shown, the present invention provides a normal pressure expansion turbine power generation system, comprising a normal pressure expansion turbine 5, a generator 1 and a compressor 9 arranged coaxially;

[0040] The generator 1 is located between the atmospheric expansion turbine 5 and the compressor 9, and the atmospheric expansion turbine 5 drives the generator 1 and the compressor 9 to rotate;

[0041] The atmospheric expansion turbine exhaust port of the atmospheric expansion turbine 5 is connected to the compressor air inlet 8 of the compressor 9 through a pipeline;

[0042] High-temperature normal-pressure gas enters from the normal-pressure expansion turbine air inlet 3 of the normal-pressure expansion turbine 5, drives the turbine blades 4 of the normal-pressure expansion turbine 5 to work, and then drives the generator 1 to work and generate electricity. The normal-pressure expansion turbine 5 drives the compressor 9 to rotate to provide vacuum for the normal-pressure expansion turbine 5, and the exhaust gas of the normal-pressure expansion turbine 5 enters the compressor 9 after cooling.

[0043] The atmospheric expansion turbine 5 mentioned in the present invention can be any conventional expansion turbine in the art. The naming of "atmospheric expansion turbine" is intended to illustrate that high-temperature atmospheric pressure gas enters the atmospheric expansion turbine 5 to perform work.

[0044] The atmospheric expansion turbine power generation system provided by the present invention can generate electricity using high-temperature atmospheric pressure gas, and can also generate electricity using high-temperature gas with a certain pressure, and can adapt to gases of different pressures and temperatures.

[0045] The present invention also includes:

[0046] The cooler 7 is connected between the atmospheric expansion turbine exhaust port and the compressor air inlet 8, and is used to cool the gas discharged through the atmospheric expansion turbine exhaust port. The cooler 7 cools the exhaust gas of the atmospheric expansion turbine, reduces the inlet working medium temperature of the compressor 9, and reduces the power consumption of the compressor 9.

[0047] In the present invention, the atmospheric expansion turbine 5, the generator 1 and the compressor 9 are connected via a rotating shaft 2. The atmospheric expansion turbine 5 is driven by the high-temperature atmospheric pressure gas to rotate and then drive the generator 1 to generate electricity through the rotating shaft 2, and drive the compressor blades 10 to pressurize the cooled gas through the compressor diffuser 11 and then discharge it from the compressor exhaust port 12.

[0048] The compressor diffuser 11 is an important component in the compressor. Its main function is to reduce the speed of the gas by gradually increasing the cross-sectional area of ​​the gas flow after the gas flows out of the compressor blades 10, and at the same time convert the kinetic energy of the gas into static pressure energy. This process helps to improve the efficiency and performance of the compressor.

[0049] In the present invention, a turbine outlet diffuser 6 is provided at the exhaust port of the atmospheric expansion turbine. The turbine outlet diffuser 6 is a component in the turbine used to decelerate and pressurize the high-speed gas at the outlet of the turbine blade 4. It is usually composed of a series of stationary blades arranged at a specific angle to reduce the kinetic energy of the gas and convert it into pressure energy. The design of the diffuser is crucial to improving the efficiency of the entire turbine because it directly affects the flow characteristics and energy conversion efficiency of the gas in the turbine.

[0050] In the present invention, the compressor 9 is a vacuum compressor. Working under normal pressure, the vacuum compressor provides a vacuum environment for the outlet of the normal pressure expansion turbine to ensure the normal pressure expansion of the turbine.

[0051] The working process of the above-mentioned atmospheric expansion turbine power generation system provided by the present invention is as follows:

[0052] High-temperature normal-pressure gas enters the atmospheric expansion turbine 5 through the atmospheric expansion turbine air inlet 3, driving the turbine blades 4 therein to rotate. The work done by the rotation of the turbine blades 4 can be transmitted to the generator 1 through the rotating shaft 2 to generate electricity. The exhaust gas of the atmospheric expansion turbine enters the gas pipeline after passing through the turbine outlet diffuser 6. After heat exchange in the cooler 7, it enters the compressor 9 from the compressor air inlet 8 through the gas pipeline. The compressor 9 compresses the exhaust gas through the compressor diffuser 11 by rotating the compressor blades 10 (the atmospheric expansion turbine 5 rotates through the rotating shaft 2 to drive the compressor blades 10 to rotate), and then discharges it through the compressor exhaust outlet 12 (preferably the pressure is increased to above atmospheric pressure for discharge). When compressing the exhaust gas, the compressor diffuser 11 can decelerate the airflow with greater kinetic energy coming out of the compressor blades 10, thereby effectively converting the gas kinetic energy into pressure energy.

[0053] In a second aspect, the present invention provides a power generation method of the above-mentioned atmospheric expansion turbine power generation system, comprising the following steps:

[0054] High-temperature normal-pressure gas enters from the normal-pressure expansion turbine air inlet 3, drives the turbine blades 4 to work, and further drives the generator 1 to work and generate electricity;

[0055] The atmospheric expansion turbine 5 is coaxial with the compressor 9 , and the turbine blades 4 drive the compressor 9 to rotate through the rotating shaft 2 to provide vacuum for the atmospheric expansion turbine 5 .

[0056] In a third aspect, the present invention provides the application of the above atmospheric expansion turbine power generation system or the above power generation method in industrial waste heat recovery and distributed energy. The details are as follows:

[0057] (1) Industrial waste heat recovery: In high-temperature industrial processes such as steelmaking, glass manufacturing, and chemical industry, a large amount of high-temperature and normal-pressure gas is often produced. The present invention can directly utilize these gases for energy conversion without the need for additional pressurization, thus simplifying system design and reducing costs.

[0058] (2) Recycling of waste heat from power plants: In the process of gas turbine power generation or other thermal power generation, the high-temperature and normal-pressure gas discharged can be reused through the present invention to improve the overall power generation efficiency. In a small-scale cogeneration system, the present invention can also use the waste heat generated by industrial or commercial facilities to produce electricity, thereby improving energy utilization efficiency.

[0059] (3) Distributed power generation: The present invention can be used in small distributed energy systems, such as commercial buildings, industrial parks and residential areas, to provide localized power supply by recovering high-temperature, normal-pressure gas discharged from boilers or other heat sources.

[0060] The above are only preferred specific implementations of the present invention; however, the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and improved concepts of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A normal pressure expansion turbine power generation system, characterized in that: It includes a coaxially arranged atmospheric expansion turbine, a generator and a compressor; The generator is located between the atmospheric expansion turbine and the compressor, and the atmospheric expansion turbine drives the generator and the compressor to rotate; The atmospheric expansion turbine exhaust port of the atmospheric expansion turbine is connected to the compressor air inlet of the compressor through a pipeline; High-temperature normal-pressure gas enters from the air inlet of the normal-pressure expansion turbine, drives the turbine blades of the normal-pressure expansion turbine to work, and then drives the generator to work and generate electricity. The normal-pressure expansion turbine drives the compressor to rotate to provide vacuum for the normal-pressure expansion turbine, and the exhaust gas of the normal-pressure expansion turbine enters the compressor after cooling.

2. A normal pressure expansion turbine power generation system according to claim 1, characterized in that: Also includes: A cooler is connected between the exhaust port of the atmospheric expansion turbine and the air inlet of the compressor, and is used for cooling the gas discharged through the exhaust port of the atmospheric expansion turbine.

3. The atmospheric expansion turbine power generation system according to claim 1, characterized in that: The atmospheric expansion turbine, the compressor and the generator are connected via a rotating shaft.

4. The atmospheric expansion turbine power generation system according to claim 1, characterized in that: A turbine outlet diffuser is arranged at the exhaust port of the atmospheric expansion turbine.

5. A normal pressure expansion turbine power generation system according to any one of claims 1 to 4, characterized in that: The compressor is a vacuum compressor.

6. A power generation method of a normal pressure expansion turbine power generation system according to any one of claims 1 to 5, characterized in that: The steps include: High-temperature atmospheric pressure gas enters from the atmospheric pressure expansion turbine air inlet, drives the turbine blades to work, and then drives the generator to work and generate electricity: The atmospheric expansion turbine is coaxial with the compressor, and the turbine blades drive the compressor to rotate via a rotating shaft to provide vacuum for the atmospheric expansion turbine.

7. Application of a normal pressure expansion turbine power generation system according to any one of claims 1 to 5 or a power generation method according to claim 6 in industrial waste heat recovery and distributed energy.

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