Method for accounting carbon emission in whole life cycle of rice bran oil production

Abstract

The invention belongs to the technical field of life cycle evaluation, and relates to a method for accounting carbon emission in the whole life cycle of rice bran oil production. A life cycle evaluation method is used for evaluating carbon emission in the whole life cycle of rice bran oil production and carbon emission reduction of four clean power generation modes (hydroelectric generation, nuclear power generation, wind power generation and photovoltaic power generation), and the method comprises the following steps: firstly, determining a system boundary of the life cycle of rice bran oil production; and then collecting material, resource and energy consumption data of a raw material acquisition stage, a transportation stage, a production and processing stage and a finished product oil packaging stage in the whole life cycle of rice bran oil production, establishing a carbon emission accounting model to calculate carbon emissions generated in different stages, and performing result analysis by using CML2011. According to the invention, carbon emission generated in each stage of the whole life cycle of rice bran oil production is quantified from the perspective of the whole life cycle, the carbon emission of rice bran oil production after four clean power generation modes are adopted is calculated, and improvement measures can be provided accordingly.

Description

Technical Field

[0001] The invention belongs to the technical field of life cycle assessment and relates to a method for calculating carbon emissions over the entire life cycle of rice bran oil production. Background Art

[0002] The nutritional content of rice bran accounts for almost 60% of the nutritional value of rice, covering more than 90% of the essential elements for the human body, and is a natural source of nutrition. The oil content of rice bran is 12%-18%, which is an important source of oil, close to the oil content of soybeans. Rice bran oil is rich in oryzanol, sterols, vitamin E and other active substances that are beneficial to human health. It has the effect of lowering blood lipids and cholesterol, and also has a certain effect on preventing hyperlipidemia, hyperglycemia, cardiovascular diseases, etc. With the improvement of people's living standards and the pursuit of health, the market demand for rice bran oil has gradually increased, and large edible oil companies have also increased the production of rice bran oil. As the production of rice bran oil increases, the carbon emissions and energy consumption will also increase. The energy conservation and environmental protection problems of rice bran oil processing industry are still severe, most of which come from the combustion and utilization of fossil energy. Controlling the use of fossil energy is conducive to mitigating the adverse effects of climate change. It is imperative to seek clean production measures for energy conservation and emission reduction.

[0003] Currently, there is very little research on the environmental impact of rice bran oil's life cycle, and the system boundary of this research is from "gate to gate" and is not comprehensive. No research on the carbon emissions of rice bran oil from "cradle to gate" has been found so far. Therefore, a more comprehensive, scientific and reliable carbon emission accounting method is needed to calculate the carbon emissions of rice bran oil from "cradle to gate". Summary of the invention

[0004] In order to solve the above problems, the present invention proposes a method for calculating the carbon emissions of rice bran oil production over the entire life cycle.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A method for calculating carbon emissions during the entire life cycle of rice bran oil production comprises the following steps:

[0007] (1) Determination of objectives and scope: Rice bran oil production includes the stages of raw material acquisition, transportation, production and processing, and finished oil packaging. The boundaries are set as the above four stages, and the resources, energy, material inputs and greenhouse gas emissions of each stage within the system boundary are considered. The functional unit is defined as one ton of refined rice bran oil. For the electricity source of the production and processing stage, clean energy is used, such as hydropower, nuclear power, wind power, and photovoltaic power, and the carbon emissions of the four clean energy sources are calculated separately.

[0008] (2) Inventory analysis: Collect data on material, resource, and energy consumption at each stage of the process of raw material acquisition, transportation, production and processing, and finished oil packaging. The data mainly comes from two sources: one is from information released by relevant management departments, industry feasibility study reports, environmental impact assessment reports and other existing materials and published relevant references; the other is from the database in the life cycle assessment analysis tool GaBi and simapro software.

[0009] (3) Carbon emission accounting: Based on the inventory data, the carbon emission factor method is used for calculation, and four clean energy use scenarios are set in the production and processing stage, namely hydropower generation, wind power generation, nuclear power generation and photovoltaic power generation. The carbon emissions of the four clean energy sources are calculated and compared.

[0010] (4) Result analysis: Evaluate the results of carbon emission accounting, analyze the carbon emissions of the four stages of rice bran oil production, and compare the carbon emissions of the four clean energy sources, analyze which clean energy can better reduce carbon emissions, and put forward corresponding suggestions.

[0011] Beneficial effects of the present invention:

[0012] The carbon emissions and energy consumption of rice bran oil production throughout its life cycle were quantified from a full life cycle perspective, which can provide a more systematic and comprehensive understanding of the specific impact of rice bran oil production on the environment and energy. Secondly, four different clean energy sources were considered, and the carbon emissions of four power generation scenarios were calculated respectively, providing a reference for the selection of production and processing technologies in the oil and fat industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 Schematic diagram of the entire life cycle boundary of rice bran oil production. Specific implementation plan

[0014] The specific implementation of the present invention is further explained in combination with the technical scheme and the accompanying drawings.

[0015] The case of rice bran oil production and processing stage selected data from the environmental impact assessment report and the completion environmental acceptance report of a rice bran oil processing project in Jiangsu. Some of the data were obtained through actual investigations, and the data for raw material acquisition, transportation, and finished oil packaging came from actual investigations, existing references, etc. The project has an annual output of 10,000 tons of rice bran oil and is expected to be completed in 6 months. The production process includes pretreatment of rice bran, extraction of crude rice bran oil, and oil refining. The main production equipment includes rice bran separation screens, crude oil coolers, decolorization towers, biomass steam boilers, etc. Background data such as electricity, n-hexane, phosphoric acid, kaolin, edible salt, etc. come from Gabi and simapro databases.

[0016] Select CML2011-JAN.2016 as the evaluation method of this embodiment. Select the indicator global warming potential (GWP100years) as the research target. Select the production of one ton of refined rice bran oil as the functional unit. The results show that for every ton of refined rice bran oil produced, the greenhouse gas emissions generated in the raw material acquisition stage are 1.34E+05kgCO2eq; the greenhouse gas emissions generated in the transportation stage are 4.92E+01kgCO2eq; the greenhouse gas emissions generated in the production and processing stage are 3.01E+02kgCO2eq; and the greenhouse gas emissions generated in the finished oil packaging stage are 1.30E+02kgCO2eq.

[0017] Choosing hydropower generation in the production and processing links reduces 1.69E+02kgCO2eq; choosing nuclear power generation in the production and processing links reduces 1.70E+02kgCO2eq; choosing wind power generation in the production and processing links reduces 1.68E+02kgCO2eq; choosing photovoltaic power generation in the production and processing links reduces 1.59E+02kgCO2eq. Nuclear power generation reduces more carbon emissions.

[0018] 1. Use hydropower in the production and processing stage

[0019] The water energy used in hydropower generation is mainly the potential energy stored in the water body, and different types of hydropower stations are used to convert water energy into electrical energy. The production and processing stage requires 210kwh of electricity. Using CML2011-JAN.2016 for analysis, it can be concluded that the use of hydropower generation will reduce carbon emissions by 1.69E+02kgCO2eq for each ton of refined rice bran oil produced.

[0020] 2. Nuclear power generation in the production and processing stage

[0021] Nuclear power generation uses the heat released by nuclear fission in nuclear reactors to generate electricity. Its carbon emission factor is 0.0045kgCO2 / kg, and the carbon emission of 210kwh electricity is 0.945kgCO2eq. The carbon emission reduction of each ton of refined rice bran oil produced is 1.70E+02kgCO2eq.

[0022] 3. Use wind power in the production and processing stage

[0023] Wind power generation refers to the process of converting the kinetic energy of wind into electrical energy. Wind power generation uses wind energy, a clean and pollution-free renewable energy, to drive the generator to generate electricity through the rotation of windmill blades, and finally converts the kinetic energy of wind into electrical energy. This technology is not only environmentally friendly, but also has abundant wind energy resources. Using CML2011-JAN.2016 for analysis, the carbon emissions reduced for each ton of refined rice bran oil produced is 1.68E+02kgCO2eq.

[0024] 4. Use photovoltaic power generation in the production and processing stage

[0025] Photovoltaic power generation is a technology that uses the photovoltaic effect of semiconductor interfaces to directly convert sunlight energy into electrical energy. It mainly consists of three parts: solar panels (modules), controllers and inverters, and the main components are electronic components. Using CML2011-JAN.2016 for analysis, the carbon emissions reduced for each ton of refined rice bran oil produced is 1.59E+02kgCO2eq.

[0026] This method calculates the carbon emissions generated by each life cycle stage and energy material input of rice bran oil production, analyzes and compares the carbon emissions that can be reduced by four power generation methods, and proposes improvement measures based on this.

Claims

1. A method for calculating the carbon emissions of rice bran oil production over its entire life cycle, characterized in that: The steps include: (1) Determination of objectives and scope: Rice bran oil production includes the stages of raw material acquisition, transportation, production and processing, and finished oil packaging; the boundary is defined as the above four stages, and the resources, energy, material inputs and greenhouse gas emissions of each stage within the system boundary are considered; the functional unit is defined as one ton of refined rice bran oil; the electricity source for the production and processing stage is clean energy, including hydropower, nuclear power, wind power and photovoltaic power, and the carbon emissions of the four clean energy sources are calculated separately; (2) Inventory analysis: Collect data on materials, resources, and energy consumption at each stage of the process of raw material acquisition, transportation, production and processing, and finished oil packaging; (3) Carbon emission accounting: Based on the inventory data, the carbon emission factor method is used for calculation. Four clean energy use scenarios are set in the production and processing stage, namely hydropower generation, wind power generation, nuclear power generation and photovoltaic power generation. The carbon emissions of the four clean energy sources are calculated and compared; (4) Result analysis: Evaluate the results of carbon emission accounting, analyze the carbon emissions of the four stages of rice bran oil production, and compare the carbon emissions of the four clean energy sources, analyze which clean energy can better reduce carbon emissions, and put forward corresponding suggestions.

Images