Turning waste into green energy, making environment and economy win-win.

The picture shows the application of biodiesel refining exhibited at the 2023 Shanghai International Low-carbon Smart Travel Exhibition (data picture). According to our database

● Li He

Recently, the State Council issued the Action Plan for Promoting Large-scale Equipment Renewal and Trade-in of Consumer Goods (hereinafter referred to as the Plan). The "Proposal" proposes to actively and orderly develop biomass liquid fuel with waste oil and non-grain biomass as the main raw materials.

Driven by the goal of "double carbon", biomass liquid fuel with good "carbon reduction" properties has attracted much attention. The "Blue Book of 3060 Zero-carbon Biomass Energy Development Potential" jointly issued by the Biomass Energy Industry Branch of China Industry Development Promotion Association and the Environmental Engineering Evaluation Center of the Ministry of Ecology and Environment predicts that from 2021 to 2030, the application of fuel ethanol and biodiesel will be one of the important ways to reduce emissions in road transportation, and bio-aviation fuel will be gradually applied to the aviation field. From 2021 to 2030, it is estimated that the use of biomass liquid fuel will exceed 25 million tons, reducing carbon emissions by about 180 million tons in the transportation field.

Zhang Dayong, Deputy Secretary-General of China Industrial Development Promotion Association and Secretary-General of Biomass Energy Industry Branch, said that the promulgation of "Program" released a positive signal for the resource utilization of organic wastes such as agricultural and forestry biomass and kitchen.

Iteration of biofuel ethanol to non-grain raw materials

Biomass liquid fuel refers to liquid fuel such as ethanol or oil made from biomass through fermentation purification or biochemical synthesis. At present, biomass liquid fuels mainly include biofuel ethanol, biodiesel, green methanol and sustainable aviation fuel.

Among them, biofuel ethanol refers to the anhydrous ethanol with water volume less than 0.5% obtained by fermenting and distilling plants to obtain ethanol with a concentration of about 95% and then dehydrating and denaturing it.

According to different raw materials, biofuel ethanol can be divided into the first generation, the first generation, the second generation and the third generation. The raw materials of the first generation biofuel ethanol are mainly corn, wheat and other food crops. The raw materials of the first and fifth generation biofuel ethanol are mainly non-food crops such as cassava, sweet potato and sweet sorghum. The raw materials of the second generation biofuel ethanol mainly come from agricultural and forestry wastes. The raw materials of the third generation biofuel ethanol are green plants such as algae.

Large-scale production of green methanol needs to be improved

Green methanol is also favored and is constantly setting off an investment boom. For example, Jixi City, Heilongjiang Province, wind power coupled biomass green methanol integration (Phase I) project was put on record, and the project plans to build a 300,000-ton green methanol plant with a total investment of 5.2 billion yuan; CGNPC Xing ‘an League signed an integrated project of 2 million kilowatts of wind power to produce hydrogen and methanol, with an annual output of about 800,000 tons of green methanol and a total investment of 16 billion yuan …

"Biomass-to-methanol, carbon dioxide hydrogenation driven by hydrogen production from renewable energy, and biomass coupling with hydrogen production from renewable energy to synthesize methanol are the main technical paths for green methanol production. Among them, biomass gasification technology, large-scale hydrogen production technology adapted to the law of wind and light power generation, and carbon dioxide hydrogenation to methanol technology have completed several industrial pilot projects, but there are no operating cases of green methanol synthesis devices with a scale of over 100,000 tons, and large-scale production technology needs to be demonstrated and improved. " Wang Jijie, a researcher at Dalian Institute of Chemical Physics, Chinese Academy of Sciences, said.

Biodiesel technology continues to develop.

On April 3 this year, the General Department of the National Energy Administration issued the Notice on Publicity of Biodiesel Popularization and Application Pilots, and publicized 22 pilot projects of biodiesel popularization and application in Haidian District, Shijiazhuang and Guangzhou.

Biodiesel is a renewable energy source produced from waste oil and other biomass, which can directly replace petrochemical diesel as the fuel of existing engine systems. Compared with ordinary petrochemical diesel, biodiesel has more advantages in fuel performance, lubricity and renewability, and can also significantly reduce the emissions of toxic substances such as greenhouse gases, sulfur and aromatic hydrocarbons.

Biodiesel has experienced three generations of development. Zhang Dayong said that the raw materials of the first and second generation biodiesel came from vegetable oil, animal oil and waste cooking oil. The technology of the first generation biodiesel is mature, accounting for more than 85%, but it has some shortcomings, such as poor fluidity at low temperature and unsuitable for long-term storage, which affects the blending ratio. The second generation biodiesel has excellent performance, good engine compatibility and environmental friendliness, and is gradually being commercialized. The raw materials of the third generation biodiesel come from non-oil biomass such as sawdust and crop straw and microbial oil. At present, there are two main preparation methods: gasification of non-oil biomass and preparation of biodiesel from microbial oil. Although the extraction and separation are difficult and the production cost is high, it has a higher carbon emission reduction effect, and the raw materials do not occupy cultivated land and have no scale restrictions, so it is a preparation process with long-term development potential.

Sustainable aviation fuel for commercial aircraft.

Sustainable aviation fuel (SAF) refers to aviation fuel made from biological wastes or renewable resources, which has passed safety certification and sustainable certification.

Recently, China Petrochemical Co., Ltd. (hereinafter referred to as China Petrochemical Company) and Total Energy Company signed a cooperation framework agreement in Beijing, which will jointly produce SAF from waste oils and fats in a refinery of China Petrochemical Company, with an annual production capacity of 230,000 tons.

Bio-jet fuel is one of SAF. China Petrochemical Company developed the bio-jet fuel production technology with independent intellectual property rights in 2009, and produced qualified bio-jet fuel for the first time in December 2011. In April 2013, the aircraft fueled with China Petrochemical Bio-jet fuel successfully made a test flight at Shanghai Hongqiao Airport. In 2015, it made a commercial flight from Shanghai to Beijing on domestic routes, and in 2017, it made an transoceanic flight from Beijing to Chicago on international routes. China has also become the first country in Asia and the fourth country in the world with independent research and development of bio-jet fuel technology.

In May, 2022, China’s first 100,000-ton/year bio-jet fuel industrial plant was put into trial production in Zhenhai Refining and Chemical Company. The raw material was waste oil from restaurants, and it won the first global RSB (Sustainable Biomass Roundtable) certification for biomass sustainable aviation fuel in Asia. In September of the same year, China’s first batch of large-scale production of bio-jet fuel obtained airworthiness certificates.

Mo Dingge, former chairman of China Petrochemical Ningbo Zhenhai Refining & Chemical Co., Ltd., said that compared with the traditional petroleum-based aviation kerosene, the bio-jet fuel produced by Zhenhai Refining & Chemical Co., Ltd. with waste oil as the main raw material can reduce the carbon dioxide emission by more than 70% in the whole life cycle.

How to promote the development of biomass liquid fuel? Zhang Dayong suggested: "We can increase technology research and development, encourage production enterprises to cooperate with universities and research institutes in the United Nations, strengthen research and development and popularization of key technologies and equipment for biomass liquid fuel, achieve technological breakthroughs as soon as possible, and reduce production and operation costs." He believes that the technologies related to the preparation of biomass liquid fuel from cellulose and microalgae can be included in the Catalogue of Low-carbon Technologies for National Key Promotion, and promoted and applied. Accelerate the construction of green certification system, encourage biomass liquid fuel production enterprises to actively access the voluntary certification platform for zero-carbon energy certificates, conduct green certification and trading, and promote international mutual recognition of green certification mechanisms.

According to Science and Technology Daily