A method for reducing carbon emissions by gasifying power generation of municipal solid waste

Abstract

The present invention discloses a carbon emission reduction method for urban solid waste gasification power generation, including step 1: calculating the power generation of various types of urban solid waste through gasification technology; step 2: calculating the carbon emissions of each stage according to the activities in the whole life cycle of urban solid waste treated by gasification technology, and then estimating the greenhouse effect caused; step 3: evaluating the economic feasibility of operation by establishing revenue maximization cost, and determining the net profit according to the revenue source and total cost; step 4: solving the optimal solution through the established dual-objective model. The present invention is based on advanced and clean gasification technology, evaluates the power generation potential of urban solid waste, and takes greenhouse gas emissions into consideration, applies life cycle analysis to determine the material flow and energy flow of the system, and quantitatively analyzes greenhouse gas emissions, so as to evaluate the environmental performance of gasification technology. While controlling carbon emissions, the economic return of operation is guaranteed.

Description

Technical Field

[0001] The invention belongs to the technical field of carbon emission, and specifically relates to a carbon emission reduction method for power generation through gasification of urban solid waste. Background Art

[0002] The rapid growth and improper treatment of municipal solid waste have led to many serious social and environmental problems, and are also important issues that need to be urgently addressed in the field of sustainable development. Waste-to-energy technology is considered the best option for sustainable treatment of municipal solid waste and obtaining renewable energy. Gasification technology, as a thermal treatment method for treating municipal solid waste, has the following advantages:

[0003] Efficient energy conversion: Gasification technology can convert municipal solid waste into renewable energy while generating high-quality heat and electricity. This is particularly important in the search for sustainable waste disposal methods, as it not only treats waste but also converts it into useful energy.

[0004] Environmental friendliness: Gasification technology produces lower emissions during operation than traditional waste treatment methods. Direct municipal solid waste gasification at high temperatures can reduce the emission of many harmful substances, such as dioxins and PCBs, making the process more environmentally sustainable.

[0005] Reduce waste volume: Gasification can effectively reduce the volume of municipal solid waste, thereby alleviating environmental pressure. Most municipal solid waste can be directly converted into syngas through the gasification process. This process not only reduces the volume of waste, but also solves the environmental problems associated with municipal solid waste disposal.

[0006] Multi-purpose: Synthesis gas obtained through gasification can not only be used for power generation, but also converted into a variety of products such as hydrogen, ammonia, methanol and synthetic hydrocarbon fuels. This diversity makes gasification technology more advantageous in terms of resource utilization.

[0007] However, gasification technology also has the following disadvantages in treating urban solid waste: high greenhouse gas emissions; during the gasification process, biomass is converted into pyrolysis gas, which leads to higher carbon dioxide emissions. Carbon dioxide is one of the main greenhouse gas components and poses a threat to the environment. In addition, fuel consumption during transportation, gasification and power generation also leads to significant greenhouse gas emissions, mainly carbon dioxide, methane, etc. The cost efficiency is low, and the high investment and operating costs of urban solid waste gasification are high. These high costs may have an adverse impact on economic benefits. Summary of the invention

[0008] The purpose of the present invention is to provide a carbon emission reduction method for urban solid waste gasification power generation, which combines a carbon emission model and an economic benefit model to construct a dual-objective optimization model to control carbon emissions while ensuring the economic return of the operation.

[0009] To achieve the above objectives, the present invention adopts the following technical solutions:

[0010] A method for reducing carbon emissions by gasifying urban solid waste for power generation comprises the following steps:

[0011] Step 1: Calculate the power generation of various types of municipal solid waste through gasification technology;

[0012] Power generation

[0013] in, is the amount of food waste sent from collection point i to disposal site j, α tc is the gasification conversion rate of kitchen waste; is the amount of dry garbage sent from collection point i to disposal site j, α dr is the gasification conversion rate of this type of waste;

[0014] Step 2: Calculate the carbon emissions at each stage based on the activities in the entire life cycle of gasification technology to treat municipal solid waste, and then estimate the greenhouse effect caused;

[0015] Carbon emissions E = E1 + E2 + E3, E1 is the carbon emissions from the gasification process; E2 is the carbon emissions from the transportation process; E3 is the carbon emissions related to traditional disposal;

[0016] Step 3: Evaluate the economic feasibility of the operation by establishing the revenue maximization cost and determine the net profit based on the revenue sources and total costs;

[0017] Net profit E = R1-C1-C2-C3, where R1 is the income from electricity sales and garbage disposal subsidies, C1 is the fixed cost of gasification power generation technology, C2 is the transportation cost, and C3 is the disposal cost;

[0018] Step 4: The established dual-objective model solves the optimal solution. The dual objectives include controlling carbon emissions Min(E1+E2+E3) and maximizing benefits R1-C1-C2-C3≥expected profit×ε, where ε is a multiple, ε∈[0,1].

[0019] Furthermore, the carbon emissions from the gasification process

[0020] In the formula, is the amount of food waste sent from collection point i to disposal site j, is the proportion of garbage component k in kitchen waste, Ck is the fossil carbon content of garbage component k, W k is the water content of garbage component k, G k is the conversion efficiency of gasification; is the amount of dry garbage sent from collection point i to disposal site j; β is the weight coefficient of the reaction between C and CO2, which is 44 / 12 in this embodiment; u g NCV is the weighted average net calorific value of the auxiliary fuel; EF is the amount of auxiliary fossil fuel required for gasification of each ton of municipal solid waste; c is the carbon dioxide emission coefficient of the auxiliary fuel.

[0021] Furthermore, the carbon emissions from the transportation process

[0022] In the formula, is the amount of food waste sent from collection point i to disposal site j, is the amount of dry waste sent from collection point i to disposal site j, is the amount of recyclable waste sent from collection point i to disposal site j, d ij is the transportation distance from collection point i to disposal site j, e c is the CO2 emission generated per unit of fuel used, e h is the CH4 emission generated per unit of fuel used, e n is the N2O emission generated when a unit of fuel is used, γ=21 means that the greenhouse effect caused by CH4 emission is 21 times that of CO2, and δ=310 means that the greenhouse effect caused by N2O emission is 310 times that of CO2.

[0023] Furthermore, the carbon emissions associated with the conventional disposal

[0024] In the formula, Q j The amount of waste treated by traditional thermal treatment technology, m k is the proportion of garbage component k in the garbage treated by traditional thermal treatment technology, C k is the fossil carbon content of garbage component k, W k is the water content of garbage component k, β is the weight coefficient of the reaction between C and CO2, and the value in this embodiment is 44 / 12; d l The transportation distance of waste treated by traditional thermal treatment technology is c is the CO2 emission generated per unit of fuel used, e h is the CH4 emission generated per unit of fuel used, e nis the N2O emission generated when a unit of fuel is used, γ=21 means that the greenhouse effect caused by CH4 emission is 21 times that of CO2, δ=310 means that the greenhouse effect caused by N2O emission is 310 times that of CO2; u t NCV is the weighted average net calorific value of the auxiliary fuel; EF is the amount of auxiliary fossil fuel required for traditional thermal technology treatment of each ton of municipal solid waste; c is the carbon dioxide emission coefficient of the auxiliary fuel.

[0025] Furthermore, the electricity sales income and garbage disposal subsidies are income

[0026] In the formula, is the amount of kitchen waste, The amount of dry garbage, is the amount of recyclable garbage, i is the collection point processed by site j, Q j The amount of waste processed by traditional thermal treatment technology; tc is the gasification conversion rate of kitchen waste; α dr is the gasification conversion rate of this type of garbage; p is the income from gasification technology power generation, q tc The government subsidy income for the treatment of kitchen waste is q dr is the government subsidy income for treating dry garbage, α′ is the conversion rate of garbage treated by traditional thermal treatment technology, p′ is the income from treating garbage by traditional thermal treatment technology, and q′ is the government subsidy income for treating garbage by traditional thermal treatment technology.

[0027] Fixed costs of gasification power generation technology F is the initial investment in gasification technology facilities, F l is the construction investment of traditional heat treatment technology, β is the residual value rate of the factory, and N is the disposal cycle of the facility.

[0028] Furthermore, the transportation cost is the amount of food waste sent from collection point i to disposal site j, is the amount of dry waste sent from collection point i to disposal site j, is the amount of recyclable waste sent from collection point i to disposal site j, d ij is the transportation distance from collection point i to disposal site j, is the unit cost of the transport gasification technology processing plant, Q j The amount of waste processed by traditional thermal treatment technology, d l For traditional heat treatment technology, the transportation distance is Unit cost of sending to a disposal plant with conventional thermal treatment technology.

[0029] Furthermore, the disposal cost is the amount of food waste sent from collection point i to disposal site j, is the amount of dry waste sent from collection point i to disposal site j, Q j The amount of waste processed by traditional thermal treatment technology, is the unit disposal cost of kitchen waste, is the unit disposal cost of dry garbage, and v′ is the unit disposal cost of garbage treated by traditional thermal treatment technology.

[0030] First, the environmental impact of gasification technology was comprehensively analyzed through life cycle assessment. The application of life cycle assessment covers the entire life cycle from raw material acquisition, production, use to disposal, in order to compile and evaluate all inputs and outputs of a product or system and their impact on the environment. Then, a multi-objective optimization model was established, which takes into account both environmental and economic factors. In the model, the main goal is to maximize the economic benefits of the municipal solid waste gasification process while controlling greenhouse gas emissions, so as to balance environmental protection and economic benefits. This model comprehensively considers the material and energy flows in different treatment processes and their impact on greenhouse gas emissions to optimize the gasification process. Moreover, the model allows users to freely control the gasification ratio parameter, which is to identify key environmental hotspots and potential bottlenecks in the gasification process, providing key information for the improvement and future application of gasification technology. By adjusting this parameter, researchers can better understand the changes in the environmental and economic impacts of different gasification ratios and further optimize the application of gasification technology.

[0031] The present invention is based on advanced clean gasification technology, evaluates the potential of municipal solid waste power generation, takes greenhouse gas emissions into consideration, applies life cycle analysis to determine the material flow and energy flow of the system, and conducts quantitative analysis of greenhouse gas emissions, thereby evaluating the environmental performance of gasification technology. While controlling carbon emissions, the economic return of operations is guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the processing flow structure of the present invention. DETAILED DESCRIPTION

[0033] like Figure 1 As shown, the carbon emission reduction method for urban solid waste gasification power generation provided in this embodiment includes the following steps:

[0034] Step 1: Calculate the power generation of various types of municipal solid waste through gasification technology;

[0035]

[0036] In the formula, Hj is the total amount of municipal solid waste received by site j, is the amount of kitchen waste, The amount of dry garbage, is the amount of recyclable garbage, i is the collection point processed by site j, i = 1, 2, ..., I, Q j The amount of waste that can be processed by traditional thermal treatment technology.

[0037] Garbage that can be classified for pneumatic power generation includes food waste and some dry garbage; the high carbon content in food waste provides favorable conditions for gasification and biological selection; some difficult-to-treat dry garbage (such as textiles and plastics) can be treated by gasification to reduce the emission of harmful substances and converted into synthetic gas energy.

[0038] The amount of electricity converted from food waste and dry waste classified by pneumatic technology in, is the amount of food waste sent from collection point i to disposal site j, a tc is the gasification conversion rate of kitchen waste; is the amount of dry waste sent from collection point i to disposal site j, a dr is the gasification conversion rate of this type of garbage.

[0039] Step 2: Use life cycle statistical tools to focus on the material flows of the municipal solid waste gasification disposal system and the greenhouse effect caused within the system boundary;

[0040] The carbon emissions generated by fuel consumption in the collection, transportation and gasification process are E=E1+E2+E3, where E1 is the carbon emissions from the gasification process; E2 is the carbon emissions from the transportation process; and E3 is the carbon emissions related to traditional disposal.

[0041] Carbon emissions from gasification

[0042] In the formula, is the amount of food waste sent from collection point i to disposal site j, is the proportion of garbage component k in kitchen waste, C k is the fossil carbon content of garbage component k, W k is the water content of garbage component k, G k is the conversion efficiency of gasification; is the amount of dry garbage sent from collection point i to disposal site j; β is the weight coefficient of the reaction between C and CO2, which is 44 / 12 in this embodiment; u g NCV is the weighted average net calorific value of the auxiliary fuel; EF is the amount of auxiliary fossil fuel required for gasification of each ton of municipal solid waste; cis the carbon dioxide emission coefficient of the auxiliary fuel.

[0043] Carbon emissions from transportation

[0044] In the formula, is the amount of food waste sent from collection point i to disposal site j, is the amount of dry waste sent from collection point i to disposal site j, is the amount of recyclable waste sent from collection point i to disposal site j, d ij is the transportation distance from collection point i to disposal site j, e c is the CO2 emission generated per unit of fuel used, e h is the CH4 emission generated per unit of fuel used, e n is the N2O emission generated when a unit of fuel is used, γ=21 means the greenhouse effect caused by CH4 emission is 21 times that of CO2, and δ=310 means the greenhouse effect caused by N2O emission is 310 times that of CO2.

[0045] Carbon emissions associated with traditional disposal

[0046] In the formula, Q j The amount of waste treated by traditional thermal treatment technology, m k is the proportion of garbage component k in the garbage treated by traditional thermal treatment technology, C k is the fossil carbon content of garbage component k, W k is the water content of garbage component k, β is the weight coefficient of the reaction between C and CO2, and the value in this embodiment is 44 / 12; d l The transportation distance of waste treated by traditional thermal treatment technology is c is the CO2 emission generated per unit of fuel used, e h is the CH4 emission generated per unit of fuel used, e n is the N2O emission generated when a unit of fuel is used, γ=21 means that the greenhouse effect caused by CH4 emission is 21 times that of CO2, δ=310 means that the greenhouse effect caused by N2O emission is 310 times that of CO2; u t NCV is the weighted average net calorific value of the auxiliary fuel; EF is the amount of auxiliary fossil fuel required for traditional thermal technology treatment of each ton of municipal solid waste; c is the carbon dioxide emission coefficient of the auxiliary fuel.

[0047] Step 3: Evaluate the economic feasibility of the design and operation plan by establishing revenue maximization costs; electricity sales revenue and waste disposal subsidies are the direct sources of income for the enterprise, from which total costs such as fixed costs, disposal and transportation variable costs should be deducted to determine the overall net profit.

[0048] Net profit E=R1-C1-C2-C3, where R1 is the income from electricity sales and garbage disposal subsidies, C1 is the fixed cost of gasification power generation technology, C2 is the transportation cost, and C3 is the disposal cost.

[0049] Revenue from electricity sales and waste disposal subsidies are income

[0050] In the formula, is the amount of kitchen waste, The amount of dry garbage, is the amount of recyclable garbage, i is the collection point processed by site j, Q j The amount of waste processed by traditional thermal treatment technology; tc is the gasification conversion rate of kitchen waste; α dr is the gasification conversion rate of this type of garbage; p is the income from gasification technology power generation, q tc The government subsidy income for the treatment of kitchen waste is q dr is the government subsidy income for treating dry garbage, α′ is the conversion rate of garbage treated by traditional thermal treatment technology, p′ is the income from treating garbage by traditional thermal treatment technology, and q′ is the government subsidy income for treating garbage by traditional thermal treatment technology.

[0051] Daily amortized fixed costs of gasification power generation technology F is the initial investment in gasification technology facilities, F l is the construction investment of traditional heat treatment technology, β is the residual value rate of the factory, and N is the disposal cycle of the facility.

[0052] Shipping costs is the amount of food waste sent from collection point i to disposal site j, is the amount of dry waste sent from collection point i to disposal site j, is the amount of recyclable waste sent from collection point i to disposal site j, d ij is the transportation distance from collection point i to disposal site j, is the unit cost of the transport gasification technology processing plant, Q j The amount of waste processed by traditional thermal treatment technology, d l For traditional heat treatment technology, the transportation distance is Unit cost of sending to a disposal plant with conventional thermal treatment technology.

[0053] Disposal costs is the amount of food waste sent from collection point i to disposal site j, is the amount of dry waste sent from collection point i to disposal site j, Q jThe amount of waste processed by traditional thermal treatment technology, is the unit disposal cost of kitchen waste, is the unit disposal cost of dry garbage, and v′ is the unit disposal cost of garbage treated by traditional thermal treatment technology.

[0054] Step 4: The established dual-objective mathematical model provides a solution, dual objectives: controlling greenhouse gas emissions and maximizing benefits. In this embodiment, reducing greenhouse gas emissions is the main objective Min(E1+E2+E3); and the total profit is not less than ε times the expected profit, R1-C1-C2-C3≥expected profit×ε, ε∈[0,1].

[0055] The multi-objective model constructed in this embodiment is equivalently converted into a single-objective model. The single-objective model can be solved by many mathematical software currently available on the market, and its application is simple, so it will not be described in detail.

[0056] This embodiment combines the source and downstream management of urban solid waste to achieve a balance between social and economic development and environmental and ecological protection. Based on the whole life cycle of garbage collection, transportation and disposal, domestic garbage enters the collection station according to classification supervision and is then transported to the factory for different treatments. Finally, the volume of urban solid waste is determined. Kitchen waste and dry garbage are gasified to produce value-added power products, and recyclable garbage is recycled to achieve reuse, income generation and greenhouse gas emission reduction.

[0057] The above description is only a preferred implementation manner of the present invention, but the protection scope of the present invention is not limited thereto, and any modification and replacement based on the technical solution and inventive concept provided by the present invention should be included in the protection scope of the present invention.

Claims

1. A method for reducing carbon emissions by gasifying urban solid waste for power generation, characterized in that: The steps include: Step 1: Calculate the power generation of various types of municipal solid waste through gasification technology; Power generation , in, is the amount of food waste sent from collection point i to disposal site j, is the gasification conversion rate of kitchen waste; is the amount of dry waste sent from collection point i to disposal site j, is the gasification conversion rate of this type of waste; Step 2: Calculate the carbon emissions at each stage based on the activities in the entire life cycle of gasification technology to treat municipal solid waste, and then estimate the greenhouse effect caused; Carbon emissions , Carbon emissions from the gasification process; For carbon emissions during transportation; Carbon emissions associated with traditional disposal; Carbon emissions from the gasification process ; In the formula, is the amount of food waste sent from collection point i to disposal site j, is the proportion of garbage component k in kitchen waste, is the fossil carbon content of waste component k, is the water content of garbage component k, is the conversion efficiency of gasification; is the amount of dry waste sent from collection point i to disposal site j; is the mass ratio of C to CO2 reaction, The amount of auxiliary fossil fuel required for gasification treatment of each ton of municipal solid waste; is the weighted average net calorific value of the auxiliary fuel; is the auxiliary fuel CO2 emission factor; Carbon emissions from the transportation process ; In the formula, is the amount of food waste sent from collection point i to disposal site j, is the amount of dry waste sent from collection point i to disposal site j, is the amount of recyclable waste sent from collection point i to disposal site j, is the transportation distance from collection point i to disposal site j, CO2 emissions per unit of fuel used, is the CH4 emission generated per unit of fuel used, is the N2O emission generated per unit of fuel used, The greenhouse effect caused by CH4 emissions is 21 times that of CO2. The greenhouse effect caused by N2O emissions is 310 times that of CO2; Carbon emissions associated with traditional disposal ; In the formula, The amount of waste processed by traditional thermal treatment technology, is the proportion of garbage component k in the garbage treated by traditional thermal treatment technology, is the fossil carbon content of waste component k, is the water content of garbage component k, is the weight coefficient of the reaction between C and CO2, and the value in this embodiment is 44 / 12; The transportation distance of garbage for traditional thermal treatment technology is CO2 emissions per unit of fuel used, is the CH4 emission generated per unit of fuel used, is the N2O emission generated per unit of fuel used, The greenhouse effect caused by CH4 emissions is 21 times that of CO2. The greenhouse effect caused by N2O emissions is 310 times that of CO2; The amount of auxiliary fossil fuel required for each ton of municipal solid waste treated by traditional thermal technology; is the weighted average net calorific value of the auxiliary fuel; is the auxiliary fuel CO2 emission factor; Step 3: Evaluate the economic feasibility of the operation by establishing the revenue maximization cost and determine the net profit based on the revenue sources and total costs; Net Profit , Income from electricity sales and waste disposal subsidies, is the fixed cost of gasification power generation technology, For transportation costs, for disposal costs; Step 4: The established dual-objective model solves the optimal solution. The dual objectives include controlling carbon emissions Min (E1+E2+E3) and maximizing revenue R1-C1-C2-C3 ≥ expected profit × , is the coefficient, .

2. The carbon emission reduction method for urban solid waste gasification power generation according to claim 1 is characterized in that: The electricity sales revenue and garbage disposal subsidies are income ; In the formula, is the amount of kitchen waste, The amount of dry garbage, is the amount of recyclable garbage, i is the collection point processed by site j, The amount of waste to be processed by conventional thermal treatment technologies; is the gasification conversion rate of kitchen waste; is the gasification conversion rate of this type of waste; Revenue from gasification technology for electricity generation, Income from government subsidies for the treatment of food waste, In order to obtain government subsidies for the treatment of dry garbage, The conversion rate of waste treated by traditional thermal treatment technology, The income from treating waste with traditional thermal treatment technology, government subsidy revenue for traditional thermal waste treatment technologies; Fixed daily amortized costs of gasification power generation technology , F is the initial investment in gasification technology facilities, is the construction investment of traditional heat treatment technology, β is the residual value rate of the factory, and N is the disposal cycle of the facility.

3. The carbon emission reduction method for urban solid waste gasification power generation according to claim 1, characterized in that: The shipping cost , is the amount of food waste sent from collection point i to disposal site j, is the amount of dry waste sent from collection point i to disposal site j, is the amount of recyclable waste sent from collection point i to disposal site j, is the transportation distance from collection point i to disposal site j, Unit costs of gasification technology plants, The amount of waste processed by traditional thermal treatment technology, For traditional heat treatment technology, the transportation distance is Unit cost of sending to a disposal plant with conventional thermal treatment technology.

4. The carbon emission reduction method for urban solid waste gasification power generation according to claim 1, characterized in that: The disposal cost , is the amount of food waste sent from collection point i to disposal site j, is the amount of dry waste sent from collection point i to disposal site j, The amount of waste processed by traditional thermal treatment technology, is the unit disposal cost of kitchen waste, is the unit disposal cost of dry garbage, Unit disposal cost of waste for waste treated with conventional thermal treatment technology.

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