A method for improving the conversion efficiency of solid organic matter for power generation and reducing carbon emissions

Abstract

The present application relates to the field of green power generation, and discloses a method for improving the power generation conversion efficiency of solid organic matter and reducing carbon emission, which comprises the following steps: a solid organic waste combustion step S1, a high-temperature fuel cell power generation step S2, a heat energy steam power generation step S3, a secondary steam power generation step S4, a tail gas emission step S5, and power supply S6; the present application generates electric energy through the interaction of two power generation systems, improves the power generation conversion efficiency, and reduces the power generation carbon emission; the comprehensive power generation efficiency is 45-70%, and the comprehensive carbon emission reduction amount can be reduced by 30-100%; through a power transformation system, the generated electric energy can be directly transmitted to a power grid or directly sold to a power consumer; the by-produced low-pressure low-temperature steam or hot water can be recycled or supplied to surrounding users or required devices.

Description

Technical Field

[0001] This invention belongs to the field of green power generation, and specifically relates to a method for improving the power generation conversion efficiency of solid organic matter and reducing carbon emissions. Background Technology

[0002] Solid organic matter (SOC) power generation technology is a thermal power generation technology that uses solid organic matter and its processed liquid or gaseous derivatives as fuel. Common solid organic matter includes: plants and their waste, industrial solid organic waste, coal, etc.

[0003] Due to limitations in the conversion efficiency of steam turbines to electricity, the current global conversion efficiency of various solid organic matter power generation methods is difficult to exceed 50% (246 g standard coal / kWh). At this critical juncture in global climate change response, improving power generation conversion efficiency can both reduce carbon emissions and lower power generation costs.

[0004] A common method to improve power generation efficiency is to reduce the exhaust temperature and pressure of steam. Modern steam engines operate in a high-vacuum state at their low-pressure steam outlet precisely for this purpose. Therefore, exhaust heat loss is a major loss in power generation. Exhaust heat loss in steam turbines results in a power generation efficiency of only about 40%. The remaining 40% of the heat energy can be utilized for heating; otherwise, it must be released into the atmosphere. This new power generation method is a novel, green, low-carbon, and low-cost method developed specifically to address this issue. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention discloses a method for improving the power generation conversion efficiency of solid organic matter and reducing carbon emissions. The aim is to significantly improve the comprehensive electrical energy conversion rate of various solid organic materials through this new power generation method, and completely overcome the problem of low power generation efficiency of steam turbines worldwide.

[0006] To achieve the above-mentioned technical objectives, this invention discloses a method for improving the power generation conversion efficiency of solid organic matter and reducing carbon emissions, comprising the following steps:

[0007] Step 1: Combustion of solid organic waste

[0008] Various solid organic wastes and their mixtures are dried or dehydrated, then pulverized or lumped and fed into partial oxidation reactors and complete oxidation reactors respectively. Together with the input oxygen and water vapor, they undergo high-temperature partial oxidation and complete oxidation reactions. High-temperature combustible mixed gas is generated in the partial oxidation reactor; carbon dioxide and water are generated in the complete oxidation reactor, releasing a large amount of heat.

[0009] Step 2: High-Temperature Fuel Cell Power Generation

[0010] The combustible mixture generated in the partial oxidation reactor passes through the shift reactor and the decarbonization device in sequence. Carbon monoxide and water vapor undergo a shift reaction under the action of a catalyst to generate hydrogen and carbon dioxide. Then, the mixture enters the decarbonization device to remove carbon dioxide from the gas mixture. The clean combustible mixture then enters the high-temperature fuel cell to generate electricity.

[0011] Step 3: Thermal Steam Power Generation

[0012] The large amount of heat released by the reaction in the complete oxidation reactor is absorbed by the water-cooled pipes and water-cooled walls arranged on the side wall of the complete oxidation reactor, turning water into high-temperature and high-pressure steam, which is then fed into a steam turbine generator to generate electricity.

[0013] Step 4: Secondary Steam Power Generation

[0014] During the process of cooling and purifying the high-temperature combustible mixed gas generated by the partial oxidation reactor through the cooler and purifier, a large amount of high-temperature steam generated by the cooler is merged into the output pipe of the steam generated by the complete oxidation reactor.

[0015] Step 5: Exhaust Gas Emission

[0016] After heat recovery is completed in the complete oxidation reactor, the mixture of low-temperature carbon dioxide, water vapor, hydrogen and other gases is purified, dust removed, desulfurized and denitrified, and then discharged into the atmosphere in accordance with environmental emission standards.

[0017] Step Six: Power Supply

[0018] The electricity generated by the two power generation systems, the partial oxidation reactor and the complete oxidation reactor, is directly transmitted to the power grid or electricity customers through the power transformation system.

[0019] Furthermore, in step four, the heat generated by the fully oxidized reactor is absorbed by the water-cooled heat exchange tubes and water-cooled heat exchange walls arranged on various side walls, and then converted into high-temperature, high-pressure steam that is directly transported to the steam turbine machinery to drive the steam turbine generator to generate electricity, thus converting the thermal energy and pressure energy in the steam into electrical energy.

[0020] Furthermore, in step three, in the high-temperature fuel cell, the combustible mixture undergoes an electrochemical reaction with oxygen in the air, converting the chemical energy of the combustible mixture into electrical energy. The exhaust gas temperature is above 400°C. Then, the high-temperature exhaust gas is directly transported to the interior of the complete oxidation reactor, where it mixes and exchanges with the reaction gas inside the complete oxidation reactor.

[0021] Furthermore, in step one, the reaction temperatures of the partial oxidation reactor and the complete oxidation reactor are in the ranges of 600–1500℃ and 1000–1500℃, respectively, and are adjusted by adjusting the composition and proportion of the combustible products or by adding appropriate catalysts; the generated elemental carbon powder is output or discharged with the slag.

[0022] Furthermore, oxygen and water vapor are injected into the partial oxidation reactor as oxidants, while air is injected into the complete oxidation reactor as an oxidant.

[0023] Furthermore, hydrogen, carbon monoxide, methane, carbon dioxide, and elemental carbon powder are generated in the partial oxidation reactor.

[0024] Furthermore, the side walls of the cooler are equipped with water-cooled pipes and water-cooled walls to absorb the high-temperature heat after the reaction and generate high-temperature and high-pressure steam.

[0025] Compared with the prior art, the beneficial effects of the present invention are:

[0026] This invention generates electricity through the interaction of two power generation systems, improving power generation conversion efficiency and reducing carbon emissions from power generation. The overall power generation efficiency is 45-70%, and the overall carbon emission reduction can be reduced by 30-100%. Through the substation system, the electricity can be directly transmitted to the power grid or sold directly to electricity customers. The by-product low-pressure low-temperature steam or hot water can be recycled or supplied to surrounding users or devices in need. Attached Figure Description

[0027] Figure 1 This is a flowchart of the method of the present invention.

[0028] Figure 2 This is a flowchart illustrating the implementation of the present invention.

[0029] Explanation of reference numerals in the attached diagram: 1. Partial oxidation reactor; 2. Complete oxidation reactor; 3. Cooler; 4. Purifier; 5. Shift reactor; 6. Decarbonization device; 7. High-temperature fuel cell; 8. Steam turbine generator. Detailed Implementation

[0030] Preferred embodiments of the invention will now be described in more detail. While preferred embodiments of the invention are described below, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0031] A method for improving the power generation conversion efficiency of solid organic matter and reducing carbon emissions includes the following steps:

[0032] First, plants, various solid organic wastes and their mixtures are dried or dehydrated, then pulverized or lumped and fed into partial oxidation reactor 1. Together with the input oxygen and water vapor, they undergo a high-temperature partial oxidation reaction to produce hydrogen, carbon monoxide, methane, C2-C4 and other combustible components. The reaction temperature is 600-1500℃. If the composition and proportion of combustible products are to be adjusted, appropriate catalysts can be added for regulation. Also, as needed, a portion of elemental carbon powder can be generated for output or discharged with the slag.

[0033] Meanwhile, plants, various solid organic matter, coal and their mixtures are dried or dehydrated, then pulverized and fed into the complete oxidation reactor 2, where they undergo a high-temperature complete oxidation reaction with the preheated air that is fed in, producing carbon dioxide and water and releasing a large amount of heat.

[0034] The large amount of heat released is absorbed by the water-cooled pipes and water-cooled walls arranged on the side wall of the complete oxidation reactor 2, turning the water into high-temperature and high-pressure steam. After the heat recovery is completed in the complete oxidation reactor 2, the mixture of low-temperature carbon dioxide, water vapor, hydrogen and other gases is purified, dust removed, desulfurized and denitrified before being discharged into the atmosphere, meeting the requirements of various national environmental protection emission indicators.

[0035] Then, the high-temperature combustible mixed gas generated by the partial oxidation reactor 1 is cooled and purified by cooler 3 and purifier 4. The cooling is carried out by water pipe cooling, and the high-temperature and high-pressure steam generated is fed into the steam output pipe of the complete oxidation reactor 2. The clean combustible mixed gas generated in the partial oxidation reactor 1 is transported to the shift reactor 5. In this device, carbon monoxide and water vapor undergo a shift reaction under the action of a catalyst to generate hydrogen and carbon dioxide. Then, it enters the decarbonization device 6 to remove carbon dioxide from the mixed gas. After that, the combustible mixed gas enters the high-temperature fuel cell 7.

[0036] In the high-temperature fuel cell 7, the combustible mixture reacts with oxygen in the air to convert the chemical energy of the combustible mixture into electrical energy. The electro-conversion efficiency is 45-65%, and the exhaust gas temperature is above 400°C. The high-temperature exhaust gas generated by the reaction is then directly transported to the interior of the complete oxidation reactor 2 to mix and exchange with the reaction gas in the complete oxidation reactor 2.

[0037] The heat generated by the reaction in the complete oxidation reactor 2 is absorbed by the water-cooled heat exchange tubes and water-cooled heat exchange walls arranged on various side walls, and then becomes high-temperature and high-pressure steam. This steam is directly transported to the steam turbine machinery, which drives the steam turbine generator 8 to generate electricity, converting the thermal energy and pressure energy in the steam into electrical energy. The power generation efficiency is over 40%.

[0038] The electricity generated by the two power generation systems in this method is boosted through a substation system and can be directly transmitted to the power grid or sold directly to electricity customers. The byproduct low-pressure, low-temperature steam or hot water can be recycled or supplied to surrounding users or equipment in need.

[0039] in:

[0040] (1) Partial oxidation reactor 1 is a gasifier, complete oxidation reactor 2 is a boiler, and shift reactor 5 is a shift furnace;

[0041] (2) Specific solid organic matter can be biomass such as sawdust, coal, rice husks, corn stalks, bark and roots, reeds, and bamboo shoots. In the example, sawdust is used as an example.

[0042] (3) Partial oxidation reactor 1 is a gasification reaction, and its reaction equation is:

[0043] C n O n H n +O2+H2O→CO+H2+CH4;

[0044] The complete oxidation reactor mainly uses organic matter as fuel to heat water, turning the water into steam, which in turn drives a steam turbine to generate electricity.

[0045] Example 1

[0046] Taking a 600,000 kW steam turbine generator 8 operating for 6,000 hours per year as an example, the advantages of this invention are demonstrated.

[0047] Raw materials: Partial oxidation reactor 1 uses an energy plant with a dry basis calorific value of 4000 kcal as raw material, and complete oxidation reactor 2 uses thermal coal as raw material, with the amount calculated based on the standard coal calorific value of 7000 kcal.

[0048] In this reactor, the calorific value of the feedstock in the partial oxidation reactor 1 accounts for 20% of the total calorific value of the feedstock; while in the complete oxidation reactor 2, the calorific value of the feedstock accounts for 80% of the total calorific value of the feedstock.

[0049] Partial oxidation reactor 1: Oxygen and water vapor are injected into partial oxidation reactor 1 as oxidants; a mixture of high-temperature combustible gases such as hydrogen, carbon monoxide, methane, and carbon dioxide is generated, along with some elemental carbon powder.

[0050] The high-temperature gas generated by the partial oxidation reactor 1 is cooled and purified by water cooling pipes, and the high-temperature steam generated by cooling is injected into the steam output pipe of the complete oxidation reactor 2.

[0051] The cooled and purified mixed gas undergoes a carbon monoxide and water conversion reaction to produce hydrogen and remove carbon dioxide and moisture from the mixed gas; the resulting purified combustible gas mixture enters the fuel cell to generate electricity.

[0052] The high-temperature exhaust gas generated by fuel cell power generation is directly injected into the furnace chamber of the complete oxidation reactor 2.

[0053] Complete oxidation reactor 2: Air is injected into complete oxidation reactor 2 as an oxidant; the high-temperature and high-pressure steam generated by complete oxidation reactor 2 is input into a steam turbine to generate electricity.

[0054] Among them, the reaction efficiency of the gas generated by the partial oxidation reactor 1 is 80%, the power conversion efficiency of the fuel cell is 45%, and the power generation efficiency of the steam turbine is 41%.

[0055] Data Summary unit This method conventional power generation Raw materials converted into standard coal 10,000 tons / year 120.6 108 Total annual power generation 100 million kw·h 42.3 36 Total power generation efficiency ％ 43.2 41.0 carbon emissions 10,000 tons / year 262 284 Carbon sinks generated by green power generation 10,000 tons / year 75.5 0 Coal consumption per kilowatt-hour after renovation g / kw·h 287 300

[0056] In summary, this invention has positive benefits in improving power generation conversion efficiency, reducing carbon emissions from power generation, and carbon sinks.

[0057] Example 2

[0058] The difference between this embodiment and Embodiment 1 is that the high-temperature fuel cell 7 has an electrical conversion efficiency of 60%.

[0059] Data Summary unit This method conventional power generation Raw materials converted into standard coal 10,000 tons / year 122 108 Total annual power generation 100 million kw·h 44.4 36 Total power generation efficiency ％ 43.4 41.0 carbon emissions 10,000 tons / year 266 284 Carbon sinks generated by green power generation 10,000 tons / year 86.7 0 Coal consumption per kilowatt-hour after renovation g / kw·h 283 300

[0060] In summary, this invention has positive benefits in improving power generation conversion efficiency, reducing carbon emissions from power generation, and carbon sinks.

[0061] Example 3

[0062] The difference between this embodiment and Embodiment 2 is that the calorific value of the raw material in the partial oxidation reactor 1 accounts for 60% of the total calorific value of the raw material; while the calorific value of the raw material in the complete oxidation reactor 2 accounts for 40% of the total calorific value of the raw material.

[0063] Data Summary unit This invention conventional power generation Raw materials converted into standard coal 10,000 tons / year 152 108 Total annual power generation 100 million kw·h 61.3 36 Total power generation efficiency ％ 50.7 41.0 carbon emissions 10,000 tons / year 229 284 Carbon sinks generated by green power generation 10,000 tons / year 259 0 Coal consumption per kilowatt-hour after renovation g / kw·h 242 300

[0064] In summary, this invention has positive benefits in improving power generation conversion efficiency, reducing carbon emissions from power generation, and carbon sinks.

Claims

1. A method for improving the power generation conversion efficiency of solid organic matter and reducing carbon emissions, characterized in that: Includes the following steps: Step S1: Incineration of solid organic waste Various solid organic wastes and their mixtures are dried or dehydrated, then pulverized or lumped and fed into partial oxidation reactors and complete oxidation reactors respectively. Together with the input oxygen and water vapor, they undergo high-temperature partial oxidation and complete oxidation reactions. High-temperature combustible mixed gas is generated in the partial oxidation reactor; carbon dioxide and water are generated in the complete oxidation reactor, releasing a large amount of heat. Step S2: High-temperature fuel cell power generation The combustible mixture generated in the partial oxidation reactor passes through the shift reactor and the decarbonization device in sequence. Carbon monoxide and water vapor undergo a shift reaction under the action of a catalyst to generate hydrogen and carbon dioxide. Then, the mixture enters the decarbonization device to remove carbon dioxide from the gas mixture. The clean combustible mixture then enters the high-temperature fuel cell to generate electricity. Step S3: Thermal steam power generation The large amount of heat released by the reaction in the complete oxidation reactor is absorbed by the water-cooled pipes and water-cooled walls arranged on the side wall of the complete oxidation reactor, turning water into high-temperature and high-pressure steam, which is then fed into a steam turbine generator to generate electricity. Step S4, Secondary Steam Power Generation During the process of cooling and purifying the high-temperature combustible mixed gas generated by the partial oxidation reactor through the cooler and purifier, a large amount of high-temperature steam generated by the cooler is merged into the output pipe of the steam generated by the complete oxidation reactor. Step S5, Exhaust Gas Emission After heat recovery is completed in the complete oxidation reactor, the low-temperature carbon dioxide, water vapor and hydrogen mixture is purified, dust removed, desulfurized and denitrified, and then discharged into the atmosphere in accordance with environmental emission standards. Step S6, Power Supply The electricity generated by the two power generation systems, the partial oxidation reactor and the complete oxidation reactor, is directly transmitted to the power grid or electricity customers through the power transformation system. In step S1, the reaction temperatures of the partial oxidation reactor and the complete oxidation reactor are in the ranges of 600~1500℃ and 1000~1500℃, respectively, and are adjusted by adjusting the composition and proportion of combustible products or adding appropriate catalysts; the generated elemental carbon powder is output or discharged with the slag.

2. The method for improving the power generation conversion efficiency of solid organic matter and reducing carbon emissions according to claim 1, characterized in that: In step S4, the heat generated by the complete oxidation reactor is absorbed by water-cooled heat exchange tubes and water-cooled heat exchange walls arranged on various side walls, and then converted into high-temperature, high-pressure steam that is directly transported to the steam turbine machinery to drive the steam turbine generator to generate electricity, converting the thermal energy and pressure energy in the steam into electrical energy.

3. The method for improving the power generation conversion efficiency of solid organic matter and reducing carbon emissions according to claim 1, characterized in that: In step S3, in the high-temperature fuel cell, the combustible gas mixture undergoes an electrochemical reaction with oxygen in the air, converting the chemical energy of the combustible gas mixture into electrical energy. The exhaust gas temperature is above 400°C. Then, the high-temperature exhaust gas is directly transported to the interior of the complete oxidation reactor to mix and exchange with the reaction gas in the complete oxidation reactor.

4. The method for improving the power generation conversion efficiency of solid organic matter and reducing carbon emissions according to claim 3, characterized in that: Oxygen and water vapor are injected into the partial oxidation reactor as oxidants, while air is injected into the complete oxidation reactor as an oxidant.

5. The method for improving the power generation conversion efficiency of solid organic matter and reducing carbon emissions according to claim 1, characterized in that: The partial oxidation reactor produces hydrogen, carbon monoxide, methane, carbon dioxide, and elemental carbon powder.

6. The method for improving the power generation conversion efficiency of solid organic matter and reducing carbon emissions according to claim 1, characterized in that: The side walls of the cooler are equipped with water-cooled pipes and water-cooled walls to absorb the high-temperature heat after the reaction and generate high-temperature and high-pressure steam.

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