2007 Biodiesel Industry Research Report (for those without gold coins)

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2007 Biofuel Industry Research Report: China’s oil reserves are also very limited, and heavy imports of oil pose a threat to China’s energy security. Therefore, increasing oil reserves is even more meaningful for China. Biodiesel boasts three advantages: it is renewable, clean, and safe. Experts believe that biodiesel holds great strategic significance for China’s agricultural structure adjustment, energy security, and comprehensive environmental management. 　　I. Current Status of the Industry 　　1. Overview of Biodiesel 　　Biodiesel is a clean renewable energy source. It is a liquid fuel produced from oilseeds such as soybeans and rapeseed, fruits of oil-bearing trees like oil palms and carob trees, oil-rich aquatic plants such as engineered microalgae, as well as animal fats and waste cooking oil. It serves as an excellent substitute for petroleum diesel. Biodiesel is a typical \"green energy\" source. Vigorously developing biodiesel holds significant strategic importance for the sustainable economic development, the advancement of energy substitution, the reduction of environmental pressure, and the control of urban air pollution. 　　The common methods for biodiesel production are mainly chemical and physical methods. Among them, the physical methods include direct mixing method and microemulsification method ； The chemical methods include high-temperature pyrolysis and transesterification. Currently, biodiesel is primarily produced by chemical methods; that is, animal and vegetable fats are reacted with low-carbon alcohols such as methanol or ethanol in the presence of acidic or basic catalysts and at high temperatures (230–250°C) to undergo transesterification, resulting in the formation of corresponding fatty acid methyl esters or fatty acid ethyl esters. After washing and drying, biodiesel is obtained. Methanol or ethanol can be reused in the production process; the production equipment is the same as that used in conventional oil production, and about 10% glycerin is produced as a by-product during this process. 　　Biodiesel has a wide range of applications, with the main areas including its use directly as high-quality diesel for vehicles, that is, 100% biodiesel (B100) ； Used in combination with petroleum diesel, the grades available are 2%, 5%, 10% and 20%, namely B2, B5, B10, B20 diesel ； Alternatives to diesel not for use in vehicles, such as for heating, marine use, agriculture, power generation, etc ； Used as a machining lubricant and release agent ； High-quality solvents, such as those used as paint removers (as a substitute for dichloromethane), in printing inks, and as cleaning agents. 　　Compared to conventional diesel, biodiesel has many advantages, as shown in Figure 8.1. Table 8.1 compares biodiesel with conventional diesel. Column: Differences; Conventional diesel has a calorific value of 35.5 MJ/L and a cetane number of 50 (standard) ； The calorific value of biodiesel is 32.4–36.7 MJ/L, and its cetane number is 52–70. Although biodiesel has a slightly lower calorific value, it has a high cetane number. Moreover, the oxygen-containing components in biodiesel ensure more complete combustion when mixed with conventional diesel, resulting in higher thermal efficiency. Therefore, using them together yields good performance, allows for maximum utilization of the diesel’s power, and provides excellent overload characteristics. 　　Environmental pollution: Compared to conventional diesel, vehicles using biodiesel emit only 10% of the toxic organic compounds found in diesel engine exhausts, and only 20% of particulate matter. Carbon monoxide emissions can be reduced by 95% when a catalyst is used, and there is no emission of toxic substances such as sulfur dioxide and lead. 　　Properties: The properties of biodiesel are very similar to those of conventional diesel. The kinematic viscosity of conventional diesel is 3–8, while that of biodiesel is 5–10. It can be used alone or blended with diesel in any proportion, without requiring any modifications to the engine or fuel system. Apart from a slight reduction in power when used alone, blends at less than 50% show no difference from conventional diesel. There is no mechanical damage; it does not cause corrosion to the engine or fuel system, no coking of the injectors, and no buildup of carbon deposits in the combustion chamber. It has excellent lubricating properties, which reduces the wear rate of the fuel injection pump, engine cylinder block, and connecting rods. 　　Safety: Due to its high flash point, biodiesel is not considered a hazardous material, making it relatively safe to store, transport, and use. 　　2. Overview of the Development of Biodiesel Abroad 　　With global energy shortages and rising prices, as well as increasingly stringent environmental regulations in various countries, biofuels that are readily available, inexpensive, and of high quality have emerged as attractive options. There is a growing enthusiasm for their development, and continuous breakthroughs are being achieved in related technologies. As an important petroleum refining product, diesel’s share in the fuel mix across various countries is increasing year by year. As the trend toward using diesel in vehicles accelerates worldwide, demand for diesel is expected to increase further in the future. Meanwhile, the dwindling availability of oil resources and rising environmental awareness have **spurred countries around the world to accelerate the development of alternative fuels to diesel. Especially since the 1990s, biodiesel has attracted attention from various countries due to its excellent environmental benefits. The global total production of biodiesel in 2006 reached 5 million tons, and it is expected to exceed 30 million tons by 2010. 　　(1) Europe Biodeiesel is most widely used in Europe, with rapeseed oil being the main raw material for its production. The European Parliament has exempted biodiesel from 90% of taxes. In Europe, legislative support for alternative fuels, differential taxation, and subsidies for the cultivation of rapeseed have all contributed to the rapid development of the biodiesel industry. Biodiesel’s share in Europe already accounts for over 5% of the refined oil market. According to the European Union Oilseed Industry Association (Fedio1), by mid-2006, biofuel production in the EU had exceeded 4 million tons. (Table 8.2) Table 8.2: Biofuel production in the 25 EU countries in 2005 and production capacity in 2006. Biofuel Chemicals Forum: Production in 2005 (thousands of tons), Production in 2006 (thousands of tons). Germany: 167, 268; France: 49.2, 77.5; Italy: 39.6, 85.7. Biofuel Chemicals Forum: http://forum.cbbf.cn. Austria: 8.5, 13.4; Czech Republic: 13.3, 20.3; Poland: 10, 15. Biofuel Chemicals Forum: http://forum.cbbf.cn. Slovakia: 7.8, 8.9. Biofuel Chemicals Forum: http://forum.cbbf.cn. Spain: 7.3, 22.4; Denmark: 7.1, 8.1; United Kingdom: 5.1, 44.5; Slovenia: 0.8, 1.7. Biofuel Chemicals Forum: http://forum.cbbf.cn. Estonia: 0.7, 2; Lithuania: 0.7, 1; Latvia: 0.5, 0.8; Greece: 0.3, 7.5; Malta: 0.2, 0.3; Belgium: 0.1, 8.5; Cyprus: 0.1, 0.2; Portugal: 0.1, 14.6. Biofuel Chemicals Forum: http://forum.cbbf.cn. Sweden: 0.1, 5.2. Biofuel Chemicals Forum: http://forum.cbbf.cn. (2) United States The United States was one of the first countries to conduct research on biofuels; commercial use began in the early 1990s. Federal agencies, Congress, and relevant state governments supported the production and consumption of biofuels through regulations and laws, as well as by providing subsidies and other incentives. It led to the rapid development of the biodiesel industry. 　　Currently. The United States already has several biodiesel manufacturers and suppliers, with soybean oil being the main raw material used in production. The annual production of biodiesel exceeds 300,000 tons, with a zero tax rate. While producing soybean biodiesel, the United States is also actively exploring other ways to produce biodiesel. U.S. renewable resources **laboratories produce “engineered microalgae” using modern biotechnology. Under laboratory conditions, its lipid content can be increased to 40%–60%. It is estimated that each acre of \"engine microalgae\" can produce 6,400 liters to 16,000 liters of biodiesel per year. It opens up a new pathway for the production of biodiesel. 　　In 2002, the American Society for Testing and Materials (ASTM) adopted standards for biodiesel, while also establishing stricter standards for petroleum diesel that were set to take effect in 2006, in order to promote a continuous increase in biodiesel production capacity. Biodiesel development in the United States is progressing rapidly, with plans to increase U.S. biodiesel consumption to 462 million liters by 2012. (Figure 8.1) Figure 8.1: biodiesel production in the United States from 1999 to 2004 (gallons) (3) Canada In Canada, diesel to which biodiesel has been added is called green diesel. Emission and engine tests show. The performance of green diesel is the same as that of conventional diesel with commercial nitrates added. At present, biodiesel and green diesel have not yet been put into commercial use in Canada, but vehicle tests on green diesel are underway. 　　(4) Japan and Brazil 　Japan began researching biodiesel in 1995; due to a shortage of plant oil resources, it uses frying oils as raw materials. In 1999, an industrial-scale experimental facility with a capacity of 259 liters per day was established, and currently Japan’s annual biodiesel production capacity amounts to 400,000 tons. Brazil produces biodiesel using castor oil as the main raw material; it is currently in the experimental phase. In 2004, the production of biodiesel was 4 tons, and it is expected to increase to 25,000 tons by 2007. 　　(5) Others ** South Korea currently has biodiesel production plants with an annual production capacity of 200,000 tons ； Thailand’s biodiesel development plan was released in July 2001. And implement tax reduction policies. The first biodiesel production facility has been put into operation ； The Gambia began operating its first biodiesel production facility, using peanut oil as raw material, in the first half of 2003. and received **support ； Countries such as Bulgaria, Canada, and Australia have also begun to promote the use of biodiesel in recent years. 　　The development of biodiesel in various countries is shown in Table 8.3:
Table 8.3 Overview of Biodiesel Development in Different Countries
**Biodiesel Percentage, Raw Materials, Current Status**
United States: B10–B20, soybeans; being promoted for use.
Germany: B5–B20, rapeseed oil, soybean oil, animal fats; widely used.
France: B5–B30, various vegetable oils; under research and promotion.
Italy: B20–B100, various vegetable oils; widely used.
Austria: B100, rapeseed oil, used waste oils; widely used.
Bulgaria: B100, sunflower oil, soybeans; being promoted for use.
Brazil: castor oil; in the testing phase for use in vehicles.
Australia: B100, animal fats; under research and promotion.
Sweden: B2–B100, various vegetable oils; widely used.
Chile: B5–B20, various vegetable oils; widely used.
Argentina: B20, soybeans; being promoted for use.
Canada: B2–B100, tung oil, animal fats; being promoted for use.
South Korea: B5–B20, used cooking oil, recycled edible oils, soybean oil; being promoted for use.
Malaysia: palm oil; under research and promotion.

3. Overview of Biodiesel Development in China
Although research and development of biodiesel in China started relatively late, it has progressed at a rapid pace, with some of the research results reaching international advanced levels. The research covers the distribution, selection, cultivation, genetic improvement of oil plants, as well as their processing techniques and equipment. Current research in various fields has achieved phased results, which will undoubtedly contribute to the further research and development of biodiesel in China. China’s 10th Five-Year Plan outline calls for the development of various oil substitutes, designating the development of bio-liquid fuels as a **key direction for industrial development. 　　Faced with the dual pressures of rapid economic development and environmental protection, it has become even more urgent to accelerate the industrialization of efficient and clean biodiesel. In recent years, China** and some enterprises have paid increasing attention to biodiesel. In 2004, the Department of High-Tech and Industrialization under the Ministry of Science and Technology launched the \"10th Five-Year Plan\" **scientific research program\" project titled \"Development of Biofuel Technologies\", which included aspects related to biodiesel ； In 2005, a **special project on agricultural and forestry biomass engineering**, led by Academician Shi Yuanchun, was launched. The plan was to achieve a biodiesel production volume of 2 million tons by 2010 and 12 million tons by 2020 ； In 2005, research on a development strategy for alternative fuels, led by Academician Hou Xianglin, was initiated; biofuel was included among these alternative fuels ； In April 2005, the Industrial Department of the **Commission for Development and Reform organized a seminar on strategies for the scientific and technological development as well as industrial growth of bioenergy and biochemical products, including biodiesel ； In May 2005, the **863 Program’s Biotechnology and Modern Agriculture sector decided to launch ahead of schedule the “Biological Energy Technology Development and Industrialization” project; guidelines were issued, which included a topic titled “Research and Industrialization of Key Technologies for Biodiesel Production”. In recent years, China has achieved phased results in research related to biodiesel in various aspects, and has been the first to carry out production through private enterprises; this will undoubtedly contribute to further research and development of biodiesel in China. 　　In China, biodiesel is increasingly favored by private enterprises. Companies such as Hainan Zhenghe Bioenergy Company, Sichuan Gushan Oil and Chemical Company, and Fujian Zhuoyue New Energy Development Company have built production facilities with an annual capacity of 10,000 to 20,000 tons. At present, waste oil from the food service industry is the cheapest raw material for biodiesel; private enterprises mainly use this waste oil along with by-products from saponification processes as raw materials, and they also produce some high-value-added products to increase their profits. Other private enterprises such as Xi’an Lantian Bioengineering Company are also producing or planning to produce biodiesel. Since 2004, the College of Life Sciences at Sichuan University has announced its intention to use the fruits of the jatropha plant to produce oil, in order to build a biodiesel refinery with an annual production capacity of 10,000 tons. Xinjiang plans to construct a biodiesel refinery with an annual output of 100,000 tons, using cottonseed oil as raw material. Hebei Shijiazhuang Refining and Chemical Co., Ltd. intends to build a bio-refinery with an annual production capacity of 50,000 tons, utilizing various types of crude oils. In 2005, another company was established in China: Weihai BILU Bioenergy Co., Ltd., founded solely by the Austrian company BIO-LUX. With an investment of 75 million euros, this company built a bio-refinery in Weihai, Shandong, with an annual production capacity of 250,000 tons; all of the products produced there were exported to the EU. In December 2005, the British SunTech Group signed a cooperation agreement on a biomass energy project with the people of Liangshan Prefecture; it planned to invest 4 billion yuan to plant 1 million mu of jatropha plants in the Panxi region for the production of biodiesel. In 2005, the American company Baker Biofuels planted 20,000 acres of jatropha trees in Panzhihua, and plans to invest $2 billion over the next few years to establish the world’s largest bioenergy facility, capable of producing nearly 400,000 tons of biodiesel per year. On December 4, 2006, the biodiesel project of Minghui Biofuel Co., Ltd. in Liuzhou, Guangxi, achieved successful trial production, with 15 tons of biodiesel produced in the first batch. The 15 tons of biodiesel produced in the initial trial run were made from woody oil crops that can be widely grown in Guangxi, such as jatropha, tung trees, and camellia trees, using the company’s proprietary \"fatty acid methyl ester purification molecular distillation technology\". The company is also planning to build a biodiesel production line with a capacity of 100,000 tons, aiming to reach an annual production volume of 300,000 tons by the end of 2008. The total investment required for this project is 130 million yuan. The biodiesel production project with an annual capacity of 100,000 tons, funded by Beijing Qingyan Lihua Petrochemical Technology Co., Ltd., was established on December 28, 2006, in the Gu’an Development Zone in Hebei Province. The investment in this project amounted to 50 million yuan, and it is primarily used for producing B100, B50, and B30 biodiesel. As planned, the project was completed on November 18, 2006, and put into operation on December 18. The project utilizes the “one-step biodiesel production technology” independently developed by Qingyan Lihua Company, which holds independent intellectual property rights. (Table 8.4) Table 8.4 Overview of Some Existing and Planned Biodiesel Manufacturers in China Company Name Location Capacity Raw Materials Technology Hainan Zhenghe Bioenergy Company Wu’an, Hebei 10,000 tons/year Grease from kitchens, waste residues from oil extraction, and oils from forest trees Chemical continuous process with pre-esterification using resin catalysts Sichuan Gushan Oil Chemistry Co., Ltd. Santai County High-Tech Zone, Mianyang 140,000 tons/year Rapeseed oil with high erucic acid content, soybean oil residues, waste animal and plant oils, and grease from kitchens Self-developed medium-pressure continuous catalytic esterification process and high-pressure continuous catalytic esterification process Fujian Longyan Zhuoyue New Energy Development Co., Ltd. Longyan, Fujian 20,000 tons/year Grease from kitchens and other waste animal and plant oils Chemical continuous process (with independent research and development in oil separation, purification, and catalysis) Wuxi Huahong Biofuel Co., Ltd. Fangqian Town Industrial Zone, Wuxi New Area 100,000 tons/year Grease from kitchens and waste animal and plant oils (waste palm oil) Technology imported from Japanese company HAVE, with additional independent research and development Fujian Yuanhua Energy Technology Co., Ltd. Qiaoshan District, Hangzhou 50,000 tons/year Grease from kitchens, residues from animal and plant oils, and industrial waste oils Technology imported from Fujian Longyan Zhuoyue Company Fujian Yuanhua Energy Technology Co., Ltd. Yuanhong Investment Zone, Fuqing, Fujian 30,000 tons/year Grease from kitchens, residues from animal and plant oils, and industrial waste oils Technology imported from Fujian Longyan Zhuoyue Company Lianmei Industry (USA) Wenrende Environmental Energy Co., Ltd. Jinshan Industrial Zone, Shanghai 100,000 tons/year Low-quality rapeseed oil and waste animal and plant oils Uses core technologies and complete sets of equipment from European biodiesel equipment suppliers BIOLUX Bioenergy Co., Ltd. Weihai 250,000 tons/year Local rapeseed oil Uses core technologies and complete sets of equipment from European equipment suppliers Hunan Tianyuan Bioclean Energy Co., Ltd. Hanshou County, Changde, Hunan 20,000 tons/year Plant oils and waste oils from restaurants Uses independently developed production technology (“A method for producing bioclean energy fuel” has been patented) Hunan Hainaibachuan Bioengineering Co., Ltd. Yiyang City, Hunan 10,000 tons/year Uses a process developed by Tsinghua University for converting renewable oils into biodiesel using lipases in organic media Rongli (**) New Energy Co., Ltd. Taicang, Jiangsu 200,000 tons/year Rapeseed oil Uses two-stage continuous alcoholysis technology from a German company Meeting the raw material needs of the biodiesel industry will be a huge challenge on a global scale. Oil-producing plants in China such as Jatropha and Melia azedarach can meet the raw material needs of a biodiesel plant with an annual capacity of 5 million tons. To address the raw material issue, some foreign companies have chosen to build biodiesel plants in China, with the products being sold abroad. Some experts believe that if foreign investors invest in biodiesel production by using China merely as a source of raw materials, it is likely to lead to shortages of such materials, which will hinder China’s efforts to develop biodiesel and address its energy shortages. II. Market Analysis of Biodiesel 　　1. Cost Analysis of Biodiesel 　　Currently, raw material prices and supply are the key factors restricting the development of biodiesel in China. The price of biodiesel should be calculated using two methods: one is the price at the net production level, and the other is a comprehensive price that takes into account factors related to consumption and the environment. 　　Calculated at the net production price, the biodiesel available in countries such as Europe and the United States costs several times more than petroleum diesel, making it uncompetitive. Taking the FRY as an example, about 360 kilograms of biodiesel can be produced from 1 ton of rapeseed, with 16 kilograms of glycerin generated as a by-product. The price of biodiesel varies depending on its grade and purity, ranging from $250 to $750 per ton, with an average price of $500 per ton. This price is not competitive compared to petroleum diesel. However, glycerin with a purity of 99.7% costs $2,000 per ton. Yugoslavia could produce approximately 3 tons of rapeseed per hectare of rapeseed fields, with a gross output value of $336 per hectare, thus maintaining a certain level of economic competitiveness. Hainan Zhenghe Bioenergy Company in China uses the waste oil from edible oil factories as raw material; 1 ton of biodiesel is produced from every 1.2 tons of such waste oil, with 50–80 kilograms of glycerin obtained as a by-product. The price of the biodiesel produced is between 2,300 and 2,500 yuan per ton. The profit per ton of biodiesel produced is 300–500 yuan, giving it a certain level of market competitiveness. Considering environmental factors and the comprehensive price of biodiesel calculated including facility investment, it is highly competitive. Due to the excellent environmental benefits of biodiesel, its production in Europe currently enjoys **tax incentives, resulting in a retail price that is lower than that of conventional diesel. If Germany implements a tax-free policy for biodiesel, its retail price at gas stations is around 1.45 marks per liter, compared to 1.60 marks per liter for diesel; thus, biodiesel is more competitive than conventional diesel. 　　Meeting the raw material demands of the biodiesel industry will be a huge challenge for the world. The amount of soybeans used will be constrained by an oversupply of soybean meal. Soybeans are seeds with low oil content; therefore, an increase in the amount of soybeans processed leads to an oversupply of soybean meal, which is difficult to store. Therefore, in comparison, other oilseeds, such as rapeseed with a high oil content, have greater potential to meet the demands of the biodiesel industry. Currently, the main raw material used for producing biodiesel worldwide is canola oil, accounting for around 84% of the total; sunflower oil comes next, while other raw materials account for a very small proportion. In China, waste oils are the main raw materials for biodiesel, while the use of large-scale vegetable oil as a raw material still needs further development. (Figure 8.2) Figure 8.2: Composition of raw materials used for biodiesel production worldwide. Due to limitations in raw material supply, China should, in the short term, utilize various existing waste oils and oily residues to produce biodiesel, such as waste oils from the food service industry, as well as industrial waste oils and residues from industries like leather and rubber manufacturing. There is little room for development in this raw material route. According to statistics, in 2005, the total supply of edible oil in China was 20.959 million tons, of which 10.14 million tons came from domestic production, accounting for only 48.4% of the total supply. Based on the assumption that 20% of edible oil is waste oil, the amount of waste oil generated is 4 million tons. Based on 15% of the amount of edible oil as the residue generated during the oil extraction process, the amount of such residue is 1.5 million tons; from this, around 10% can be recovered as waste oil, amounting to 150,000 tons. The Chinese leather industry processes an amount of leather equivalent to that of cattle skins each year, and the waste oil generated during production amounts to 40,000 to 60,000 tons. If these waste oils are used for biodiesel production on a small scale, with 50% of them converted into biodiesel, the theoretical output could reach 2 million tons. 　　Based on the current situation, raw material supply and prices have become the most challenging issues. Firstly, raw material prices have soared, taking palm oil recycled from fast-food restaurants as an example. It has risen from 2,800 yuan per ton in March 2006 to 3,500 yuan per ton, approaching the price of imported diesel; the price of B10 biodiesel is around 5,000 yuan per ton, resulting in very limited profits. Compared with the standard petrochemical diesel priced at 5,700 yuan, biodiesel is also losing its cost advantage. Another issue is the source of raw materials; existing biodiesel projects have already faced significant pressure regarding raw material availability. At present, the few projects available in the country use waste oils as raw materials, with a large proportion coming from waste kitchen grease; the amount available is very limited. Fujian Longyan Zhuoyue New Energy Development Co., Ltd. is one of the largest biodiesel production facilities in China that are already in operation; it uses waste cooking oil as raw material and has an annual production capacity of 20,000 tons, with the raw materials needing to be sourced from across the country. 　　Generally, the price of vegetable oil accounts for 70% to 80% of the cost of biodiesel, and the properties and composition of vegetable oil determine the processing procedures and product options. In the long term, China should use vegetable oils as raw materials for biodiesel production and strive to reduce their costs. Firstly, the selected oil-containing plants should, as much as possible, not conflict with the sources of edible oils ； Secondly, its production volume must be high, and the production cycle must be short. Min Enze, an academician of the Chinese Academy of Engineering and a researcher at the Research Institute of Petrochemical Science of Sinopec Corporation, suggests addressing the issue of raw material supply through the following approaches in order to reduce the cost of biodiesel: building biodiesel refineries with a capacity of 50,000 to 200,000 tons per year using rapeseed oil as the raw material. According to statistics, there are approximately 135 million mu of unused farmland in China during winter, which has the potential to produce 3 million tons of rapeseed oil; this unused land could be utilized for growing rapeseed. The drawback of using rapeseed oil to produce diesel is its high cost, around 5,000 yuan per ton. 　　Build a biodiesel refinery with an annual capacity of 50,000 to 100,000 tons using cottonseed oil as raw material. China is the world’s largest producer of cotton and cottonseed. In 2004, the cottonseed production was 8 million tons; it is estimated that this should have resulted in 1.8 million tons of cottonseed oil, whereas the consumption was only 880,000 tons. Due to its inferior quality compared to soybean oil and canola oil, the proportion of cottonseed oil used as a cooking oil is continuously declining. Therefore. Using cottonseed oil as a raw material for biodiesel production is appropriate. Currently, the price of cottonseed oil is around 4,000 yuan per ton for the crude oil, which is cheaper than rapeseed oil. If cotton seeds are processed using modern large-scale production methods, the price of cottonseed oil can be reduced to below 3,600 yuan per ton. 　　Develop plants with a capacity of less than 10,000 tons per year, tailored to the characteristics of oil-seed crops in woody plants. Developing bio-refining plants using woody plant oils as raw materials has Chinese characteristics and advantages. China possesses rich resources of woody oil-bearing plants, including Jatropha, Carapa, Terminalia, Phellodendron, Castanopsis, and Elaeocarpus, which are of wild origin. Durable in cold weather and poor soil. China currently has about 1,000 species of wild oil-bearing plants with an oil content of over 15%. About 300 species with an oil content of over 20%. Taking Sophora japonica as an example, China currently needs to afforest an area of 60 million hectares. If 5% of this area is planted with Sophora japonica, at 3,330 trees per hectare, and assuming each tree produces 20 kilograms of seeds with an oil yield of 20% to 30%, then if 50% of the oil produced is used for biodiesel production, 20 million tons of biodiesel can be manufactured from the oil generated by these trees after 4 years. Therefore, with the support and guidance of **, efforts should be made to expand the cultivation and production of wild woody oil plants; it is only after 10 years that a substantial supply of biodiesel raw materials can be expected. Persistent effort over the long term is necessary to achieve success. 　　The costs of producing biodiesel from different raw materials are shown in Table 8.5: Table 8.5 Comparison of Costs for Producing Biodiesel from Different Raw Materials (Unit: yuan) Raw Material, Raw material price, Total cost, Diesel price, Profit margin, Notes Cottonseed oil 4800 5100 4450 -650 Except for animal fats and waste oils which yield a profit, the use of other raw materials results in slight losses when producing biodiesel; however, with **subsidies, it is possible to achieve break-even or even a small profit. Rapeseed oil: 5100, 5200, 4450; -750. Animal fat: 2791, 3798, 4450; 652. Gutter oil: 2200, 3650, 4450; 800. Palm oil: 3175, 4650, 4450; -200. By-products: 600–800, 4750, 4450; -300. 2. Competitiveness analysis of biodiesel: Compared to gasoline-powered vehicles, diesel vehicles are undoubtedly more economical; they are much cheaper than hybrid vehicles in the same category, consume less fuel than gasoline vehicles of the same class, and also produce fewer greenhouse gas emissions. In Europe, diesel vehicles are very popular due to their high efficiency and energy savings; in many places, they even account for half of the total fleet. 　　On June 4, 1998, in order to improve the performance of vehicles and reduce the emission of harmful substances in vehicle exhaust, the automotive industry associations of the United States, Europe, and Japan introduced an international standard for vehicle fuel quality, namely the \"World Fuel Standard\" Category III standard. Diesel \"World Fuel Specification\" Classes II and III standards (see Tables 2 and 3). As can be seen from the table, Standard Class II sets limits on the aromatic content based on the current standards, while imposing higher requirements on sulfur content, cetane number, etc. Standard Class III has even stricter regulations for all these parameters compared to Standard Class II. (Tables 8.6 and 8.7) Table 8.6: Diesel – World Fuel Specification Class II Standards. Quality indicators: Cetane number ≥53; Sulfur content (by mass), % ≤0.03; Total aromatic hydrocarbon content (by mass), % ≤25; Polycyclic aromatic hydrocarbon content (by volume), % ≤5; 95% distillation temperature/°C ≤355. Table 8.7: Diesel – World Fuel Specification Class III Standards. Quality indicators: Cetane number ≥55; Sulfur content (by mass), % ≤0.003; Total aromatic hydrocarbon content (by mass), % ≤15; Polycyclic aromatic hydrocarbon content (by volume), % ≤2; 95% distillation temperature/°C ≤340. To meet these diesel fuel standards, refineries must adopt the following three measures using traditional processes: First, they need high-performance catalysts for deep hydrodesulfurization in order to remove aromatic sulfur compounds such as 4,6-bis**thiophene, which are difficult to remove through hydrodesulfurization ； Secondly, there is a need for sulfur-resistant precious metal aromatic saturation catalysts, which enable the hydrogenation saturation of aromatics to take place at lower pressures, thereby saving on investment costs ； Third, there must be a process to improve the cetane number. 　　Globally, crude oils with sulfur content of 0.5%–2.0% and those with a higher sulfur content (above 2.0%) account for over 75% of the world’s total crude oil production. Among them, crude oils with a sulfur content of over 1% make up more than 55% of the total global crude oil production, while those with a sulfur content of over 2.0% account for more than 30%. 　　Currently, the average relative density of crude oil processed by refineries worldwide is 0.8514, with an average sulfur content of 0.9% ； Since 2000, the average relative density will rise to 0.8633, and the sulfur content will rise to 1.6%. To reduce the sulfur content in diesel, ensure good stability and lubricity, achieve a higher cetane number, and provide excellent cleaning properties, refineries need to invest heavily in adjusting their equipment; this leads to increased costs of oil production. In this regard, refineries in developed countries have invested substantial amounts of money. 　　Looking at the situation in the United States, it began efforts to clean up its petroleum products in the early 1990s, having invested over 30 billion dollars to date. The resulting increase in oil costs means that current gross profits per ton for U.S. refineries are only around $1 per barrel, resulting in slim profits; some companies even incur losses ； In the case of Europe, European refineries are estimated to need investments of $20 billion to $30 billion in order to meet the EU fuel specifications by the year 2000. The European Petroleum Industry Association estimates higher investment amounts; it believes that 44 billion to 50 billion dollars are required to meet the diesel specifications for the years 2000 and 2005. 　　As analyzed earlier, the sulfur content in biodiesel is much lower than that in petrochemical diesel; its sulfur content as a mass fraction is only 0.5‰ of that in conventional diesel, thus eliminating the need for desulfurization processes. Thanks to its excellent environmental properties, the sulfur content of biodiesel can easily meet the requirements of diesel grades II and III under the \"World Fuel Specifications\". 　　Regarding automotive emission standards, the excellent properties of biodiesel ensure that the exhaust emission levels of engines using biodiesel not only meet the current European Standard II, but also satisfy the even stricter European Standard III. Moreover, since the carbon dioxide emitted when biodiesel is burned is much lower than the carbon dioxide absorbed during the growth of these plants, it helps to address global warming, a serious environmental problem harmful to humanity caused by carbon dioxide emissions. Therefore, biodiesel is a true green diesel. 3. Risk Analysis of Biodiesel Investment (1) Risk of Fluctuations in Product Prices As is well known, crude oil prices have been fluctuating continuously on the international stage, and diesel, which uses crude oil as its main raw material, is greatly affected by these price changes. The figure below shows a comparison between international diesel prices and crude oil prices, indicating that there is a strong correlation between these two prices; as a result, biodiesel is subject to price fluctuations. (Figure 8.3) Figure 8.3: Comparison of crude oil and diesel prices (2) Risks associated with product sales channels Biodiesel needs to enter the refined oil market through CNPC and Sinopec; therefore, biodiesel manufacturers are highly dependent on these two companies for their sales channels. There are certain risks associated with the enthusiasm for cooperation between CNPC and Sinopec. 　　(3) Risk of raw material supply The viability of a biodiesel project depends on the ability to establish a raw material supply system. Given the current situation, the few projects existing in the country use waste oils as raw materials, with a large proportion coming from kitchen waste; therefore, the amount of available raw material is very limited. Although oil crops can also be used as raw materials for biodiesel, their large-scale cultivation raises issues regarding competition with agriculture for land. 　　Fujian Zhuoyue is one of the larger biodiesel production facilities in China that is already in operation; it uses waste cooking oil as raw material to produce diesel, and its annual output of 20,000 tons still requires raw materials to be sourced from other parts of the country. Currently, 1 ton of palm oil is being sold for 3,500 yuan, leaving little profit margin at a market price of 5,000 yuan for biodiesel. And at a standard petrochemical diesel price of 5,700 yuan, the cost of biodiesel also loses its advantage. It is understood that in most areas, the only source of raw materials for biodiesel is waste grease, primarily gutter oil. Currently, existing biodiesel projects are already facing significant pressure regarding raw materials, with the supply and price of these materials representing the most challenging issues for biodiesel production. 　　III. Key factors in the operation of biodiesel 1. Raw materials for biodiesel – “fuel oil plants” Fuel oil plants, also known as “petroleum plants,” refer to plants that can directly produce industrial \"fuel oil\" or that can be processed to produce such fuel oil. Clearly, making significant efforts to introduce, discover, and cultivate \"oil plants\" so that, just as crops are sown in spring and harvested in autumn, green grass can be sown in spring and \"oil\" harvested in autumn holds great significance for an energy revolution. 　　In 1986, Dr. Calvin in the United States discovered that the chemical components in the sap of a tall evergreen tree called the rubber tree are very similar to those of diesel, and it can be used as diesel without any need for processing or refinement. This discovery prompted scientists around the world to actively search for more plants suitable for producing diesel. Over the past 20 years, through the joint efforts of scientists around the world, significant progress has been made in the search for \"fuel oil\" plants. 　　In addition to the ‘three-leaf rubber tree’, scientists have also discovered that more than 300 types of shrubs and over 400 types of flowering plants contain a certain proportion of ‘petroleum’. “\"Oil-producing plants\" are mainly found in the families Apocynaceae, Euphorbiaceae, Rubiaceae, Asteraceae, Myrtaceae, and Fabaceae. When the stems and leaves of these plants are broken, a milky white or yellow-brown liquid can be seen flowing from the wounds; this liquid contains hydrocarbons similar to those found in petroleum. It is worth emphasizing that the seed oils of these plants can be converted into biodiesel through processing. 　　China currently has over 6 million hectares of woody oilseed forests, and the annual yield of fruits from the main oilseed species exceeds 2 million tons; many of these can be used as raw materials for biodiesel production. The following are the most important species: (1) Soybean. Soybeans are grown throughout China, with the largest planting areas in the Northeast region. Soybeans are a major oil crop and a primary source of plant protein. Globally, soybeans are mainly used for oil extraction, and data from recent years show that about 85% of soybeans are used for this purpose. Nearly half of China’s domestically produced soybeans are used for food. From 1994 to 2006, the world’s main soybean-consuming countries and regions were: China, Indonesia, Japan, South Korea, and Taiwan, China. 　　The United States uses excess soybeans as a raw material to produce biodiesel, and in 2002 it proposed that over the next 20 years, biofuels would replace 25% of fossil fuels ； France has also begun to use biomass energy as a substitute for oil, which by 2007 helped reduce oil imports by about 11 million tons. The EU’s current annual biodiesel production has reached 3 million tons. The experimental results show that using a mixture of soybean oil and diesel as fuel yields the same good results as regular diesel, and it is much cleaner than regular diesel. 　　(2) Rapeseed China is a major producer of rapeseed in the world, with an annual output of 10 million tons, ranking first globally. In China, rapeseed is mainly grown in the provinces along the Yangtze River Basin; provinces such as Hubei, Hunan, Jiangsu, Anhui, and Sichuan have an annual production of over 1 million tons. China’s annual import volume of rapeseed is around 2.5 million tons. 　　The Yangtze River basin is a major production area for rapeseed in China, with the annual planting area accounting for over 80% of the country’s total rapeseed cultivation area. It is one of the three main regions in the world where brassica rapeseed is grown on a large scale. Canola oil, extracted from rapeseed, is the traditional cooking oil most favored by urban and rural residents in China. In the year 2000, China’s consumption of canola oil reached 4.19 million tons, accounting for 32.4% of the country’s annual consumption of vegetable oils, making it the most consumed type. 　　Since the 1980s, with the implementation of the **\"high-yield, high-quality, and efficient\" agriculture strategy and the adjustment of the agricultural planting structure, rapeseed has become one of the key elements in the development of winter agriculture. It has received considerable attention from the provinces and cities along the Yangtze River basin; in particular, provinces such as Hubei, Jiangxi, and Hunan have made developing rapeseed cultivation a top priority in their winter agriculture efforts for several years in a row, resulting in significant increases in both the area planted and the yields produced. 　　According to statistics, before 1980, the area devoted to rapeseed cultivation in China remained between 30 and 40 million mu; it increased to over 80 million mu by 1990, and by 2000 the area had expanded to 110 million mu. Rapeseed production increased from 2.384 million tons in 1980 to 11.381 million tons in 2000. The yield per hectare of rapeseed also increased, from 1128.8 kg per hectare in 1980 to 1518.6 kg per hectare in 2000. The growth rate of rapeseed is the highest among all oil crops in the country. Starting in 1980, China’s total rapeseed production has generally ranked first in the world. By the 1990s, China’s yield per unit area of rapeseed reached or slightly exceeded the world average. 　　(3) Kapok Kapok is one of China’s most important cash crops, mainly grown in the plains along the middle and lower reaches of the Yellow River and Yangtze River. It is also cultivated in areas with suitable conditions, such as the South Xinjiang Basin and Sichuan. 　　The cottonseed oil obtained through pressing of cottonseeds belongs to the semi-dry oil category. Biofuel can be produced by esterifying cottonseed oil. The following table shows the physical and chemical properties of the biofuel resulting from the esterification of cottonseed oil: (Table 8.8) Table 8.8: Physical and Chemical Properties of Biofuel Produced from Esterified Cottonseed Oil Parameters Values Relative density (d20℃/4℃) 0.873 Kinematic viscosity (E0 at 20℃) 6.8 Flow point (℃) -4 Flash point (℃) 234 Heat value MJ/kg NCV: 37.0–38.8 GCV: 40.58 Octane number CN: 45–52 Average molecular weight 289 It is entirely feasible to use cottonseed oil as biofuel. Through relevant experiments, Chinese researchers have reached the following conclusion: Due to its physical and chemical properties being similar to those of diesel, cottonseed oil can be used as a substitute for diesel. The lower calorific value of cottonseed oil is 87% that of diesel, and its fuel consumption rate is 13.48% higher than that of diesel; therefore, on an energy basis, their fuel consumption rates are equivalent. When cottonseed oil is used in combination with other fuels or used exclusively, the fuel supply amount does not need to be increased significantly to achieve the same power and torque. 　　Cottonseed oil and diesel are completely miscible in any proportion, so it is very convenient to mix cottonseed oil into diesel. Moreover, cottonseed oil burns in a oxygenated manner; once it catches fire, it burns rapidly and completely. Therefore, when operating at loads over 10%, the diesel engine runs more easily compared to when using diesel, and no black smoke is produced. 　　At low temperatures, the viscosity of cottonseed oil is higher than that of diesel, and its viscosity curve is steep ； At high temperatures, the viscosity decreases rapidly and the specific gravity is high; as a result, volatility is lower, leading to a longer afterburning period, which requires an appropriate increase in the fuel injection advance angle. 　　Under optimal fuel supply conditions, the use of cottonseed oil results in a decrease in both the exhaust temperature and smoke density of the diesel engine. 　　(4) Palms Palms are tropical and subtropical tree species that prefer warm and humid climates; they are relatively tolerant of cold and shade. It is cultivated south of the Qinling Mountains in China, in the middle and lower reaches of the Yangtze River, and along the coasts of South China. 　　The main component of palm oil is triglycerides, whose properties depend on the structure and number of carbon atoms in the fatty acid chains of those triglycerides. The melting point of palm oil is 30.8°C to 37.6°C, its iodine value is 50.6 to 55.1, its relative density is 0.888 to 0.889, and its refractive index is 1.455 to 1.456. Saturated and unsaturated fatty acids each account for 50% in palm oil. This average state gives palm oil better oxidation stability compared to other vegetable oils. 　　Currently, biofuel producers pay special attention to palm oil produced in Malaysia and Indonesia. Palm oil derived from oil palm ranks second only to soybean oil in the global edible oil market. It is highly competitive due to the ease of growing oil palm trees and its lower price compared to oils such as soybean oil. Currently, countries in Asia and many researchers have begun exploring ways to convert palm oil into biofuels. 　　Biodiesel can be obtained from palm oil through esterification. The table below (Table 8.9) shows the properties of the diesel produced from palm oil esterified with methanol:

Table 8.9 Physical and chemical properties of palm oil after esterification
Parameter | Value
Relative density (d20°C/4°C) | 0.869
Kinematic viscosity (E020°C) | 2.99
Flow point (°C) | -3
Flash point (°C) | 122
Calorific value MJ/kg | NCV: 35.5
Residue | 0.01
Average molecular weight | 226

(5) Jatropha
Jatropha is a deciduous shrub or small tree; in China it is mainly found in provinces and regions such as Guangdong, Guangxi, Yunnan, Sichuan, Guizhou, Taiwan, Fujian, and Hainan. It is found in areas ranging from dry and hot subtropics to humid tropical rainforests, and it can survive in environments with annual precipitation of 4.8–23.8 mm and an average annual temperature of 18.0°C–28.5°C. Jatropha is commonly found in flat areas, hills, slopes, river valleys, and barren mountains at altitudes of 700–1600 meters; it is often planted along garden edges as hedges ； There is also a semi-wild form, which commonly grows in shrubs along roads in flat areas. 　　The chemical composition of Jatropha is as follows: 6.2% water, 8% protein, 38% lipids, 17% carbohydrates, 15.5% cellulose, and 5.3% ash ； Jatropha seeds contain 35%–40% oil, with the oil content in the kernels reaching 50%–60%. The oil consists of 21% saturated fatty acids and 79% unsaturated fatty acids. 　　In tropical regions such as India and Nicaragua, jatropha seed oil is used as biodiesel. Due to its high oil content and good fluidity, it mixes well with diesel, gasoline, and ethanol; after being blended, these substances do not separate over time. Therefore, utilizing it as the most suitable renewable biofuel resource in tropical regions holds good prospects for development. (Table 8.10) The future planting area of Jatropha in China could reach at least 30 million mu. Assuming that each mu can produce 650 kg of dried fruit per year, and that 0.3 kg of diesel can be extracted from each kg of fruit, it is estimated that over 5.8 million tons of biodiesel can be produced, thus indicating good prospects for its development and utilization. 　　Table 8.10 Comparison of Diesel and Jatropha Seed Oil Properties Parameter Diesel Jatropha Seed Oil Relative density (d20°C/4°C) 0.84–0.85 0.91–0.92 Condensation point (°C) 14.0 2.0 Flash point (°C) 80 110–240 Octane number 47.8 51.0 Sulfur content/% 1.0–1.2 0.13 2. Biofuel Production Methods and Processes (1) Direct mixing method In the early stages of biofuel research, researchers proposed mixing natural oils with diesel, solvents, or alcohols in order to reduce their viscosity and increase their volatility. Adans et al. (1983) mixed degummed soybean oil with diesel No. 2 in ratios of 1:1 and 1:2 respectively, and conducted tests for 600 hours in a direct-injection turbine engine. When the two types of oil are mixed in a 1:1 ratio, the lubricant becomes cloudy and gels; this phenomenon does not occur at a 1:2 ratio, allowing it to be used as a substitute fuel for agricultural machinery. Ziejewski et al. (1983) mixed sunflower oil with diesel in a volume ratio of 1:3, and found that the viscosity of this mixture at 40°C was 4.88×10-6 m2/s. The maximum viscosity specified by ASTM (American Society for Testing and Materials) is below 4.0×10-6 m2/s; therefore, this mixed fuel is not suitable for long-term use in direct-injection diesel engines. Tests on a mixture of safflower oil and diesel yielded satisfactory results. However, over time, this mixture can still cause the lubricant to become cloudy. 　　(2) Microemulsion method Mixing vegetable and animal oils with a solvent to form microemulsions is also one of the ways to address the high viscosity of such oils. A microemulsion is a transparent, thermodynamically stable colloidal dispersion, which is a colloidal equilibrium system with a diameter of 1–150 nm formed by mixing two immiscible liquids with ionic or non-ionic amphoteric molecules. In 1982, Georing et al. prepared microemulsions using an ethanol-water solution and soybean oil; aside from a lower cetane number, these microemulsions had properties similar to those of No. 2 diesel. Ziejewski et al. (1983) prepared an emulsion using 53.3% winterized sunflower oil, 13.3% methanol, and 33.4% 1-butanol; no significant deterioration was observed during a 200-hour laboratory durability test, but issues such as carbon deposition and an increase in the viscosity of the lubricant did occur. 　　Neuma et al. (2001) developed new microemulsion systems as alternatives to diesel using surfactants, co-surfactants, water, refined diesel, and soybean oil. Among these, the microemulsion system with a composition of 63% diesel, 15.8% soybean oil, 0.9% water, 6.7% isopentanol, and 13.48% sodium dodecyl carbonate had properties most similar to those of diesel. 　　(3) High-temperature pyrolysis The initial purpose of subjecting vegetable oils to pyrolysis was to synthesize petroleum. Schwab and others analyzed the products of soybean oil pyrolysis and found that alkanes and alkenes accounted for a high proportion, making up 60% of the total mass. It was also found that the viscosity of the pyrolysis products is 1/3 that of ordinary soybeans, but this viscosity is still much higher than that of ordinary diesel. In terms of cetane number and calorific value, the pyrolysis products of soybean oil are similar to conventional diesel. 　　In 1993, Pioch et al. studied the production of biodiesel from vegetable oils through catalytic cracking. Coco oil and palm oil were pyrolyzed at 450°C using SiO2/Al2O3 as a catalyst. The products obtained from pyrolysis are divided into three phases: gas, liquid, and solid, among which the liquid phase consists of biogasoline and biodiesel. Analysis shows that the properties of this biodiesel are very similar to those of conventional diesel. (4) Transesterification method 　① Alkali-catalyzed transesterification reaction 　Acids and bases are the catalysts commonly used in the production of biodiesel, and various processes exist depending on the raw materials used. The production process using refined oils as raw materials is a batch or continuous reaction catalyzed by an alkaline catalyst at 60–70°C and 0.1 Mpa, with an alcohol-to-oil ratio of generally 6:1. After standing, the mixed product separates into an upper layer and a lower layer; the lower layer is the glycerol layer, while the upper layer is the methyl ester layer. The methyl ester from the upper layer is removed, the glycerol carried along is washed away, and further reaction yields the final product. Excess methanol is sent to a distillation tower for purification via condensation before being recycled. 　　② Biological enzyme-catalyzed transesterification reactions New research findings indicate that lipases are excellent catalysts for the transesterification of alcohols with fatty acid glycerides. As a biological catalyst, enzymes are attracting increasing attention due to their high catalytic efficiency and cost-effectiveness. Currently, the catalysts used in the chemical production of biodiesel face issues such as difficulty in separation and high energy requirements, all of which can be resolved by using enzyme catalysts. For example, fixed enzyme catalysts using porous kaolinite as a carrier not only have a longer lifespan and do not require frequent replacement compared to other catalysts, but also exhibit high activity and are easy to separate; they represent a new type of catalyst that is competitive both in terms of performance and cost. Ban et al. (2001) carried out an enzymatic reaction using olive oil and oleic acid as raw materials, achieving a methyl ester content of 90% in the product. How to increase enzyme activity and prevent enzyme poisoning is the key to this method. 　　③ Production of biodiesel without a catalyst To address issues such as high costs, long reaction times, and the difficulty in separating reactants from the catalyst in transesterification reactions, researchers have developed new processes that do not use a catalyst. M. Diasakou et al. studied the transesterification reaction between soybean oil and methanol under heating conditions, conducted kinetic studies, and determined the characteristics of the reaction in the absence of a catalyst. With an alcohol-to-oil ratio of 21:1 and a reaction time of 10 hours at 235°C, the methyl ester content exceeded 85% by mass ； With an alcohol-to-oil ratio of 27:1, the mass fraction of the methyl ester reached 67% after 8 hours of reaction at 220°C. It was also found that the conversion rates of diglycerides and triglycerides were significantly higher than that of monoglycerides; that is, in the absence of a catalyst, the first two steps of the three-step reaction proceeded rapidly, while the last step proceeded very slowly. Saka and Kusdiana (2001) proposed a critical method for producing biodiesel. The reaction takes place in a preheated batch reactor at a temperature of 350–400°C and a pressure of 45–65 Mpa, with a feed ratio of rapeseed oil to methanol of 1:42. Studies have found that methanol treated under supercritical conditions can undergo transesterification with rapeseed oil in the absence of a catalyst, yielding higher yields compared to conventional catalytic processes. The reaction takes place at lower temperatures, and it eliminates the separation and purification steps required when using a catalyst, thereby making the transesterification process simpler, safer, and more efficient. 　　The advantages and disadvantages of producing biodiesel using different processes are shown in the table below (Table 8.11). Table 8.11: Comparison of advantages and disadvantages of biodiesel production methods. Production method, Raw materials, Advantages and disadvantages: Direct mixing method – Plant oils; renewable, high calorific value, but high viscosity, prone to spoilage, and incomplete combustion. Microemulsion method – Animal and plant oils; facilitates complete combustion, can be used in combination with other methods. High-temperature pyrolysis method – Plant oils; carried out at high temperatures, requires conventional chemical catalysts, difficult to control reactants, expensive equipment. Ester exchange reaction method – Alkali-catalyzed method – Animal and plant oils as well as waste oils from the food industry; its advantages are short reaction time and lower costs. Disadvantage: Uses a large amount of methanol ； The reactants contain free fatty acids and water, which interfere with the transesterification reaction ； When residual alkali is present, soaps are formed in diesel, which can easily cause pipe blockages. The products of the transesterification reaction must be washed, and the waste liquid resulting from this washing process, containing alkaline catalysts, glycerol, and methanol, must be treated. Acid-catalyzed method: Used for animal and plant oils as well as waste oils from the food industry; the catalytic effect is better when the levels of free fatty acids and water in the oils are high. Enzyme-catalyzed method: Also used for animal and plant oils and waste oils from the food industry; the levels of free fatty acids and water have no impact on the reaction, making this method relatively cleaner ； Disadvantage: A high transesterification rate cannot be achieved without using organic solvents ； When a certain amount of methanol is present in the reaction system, the lipase becomes inactive ； Enzymes are expensive and the reaction time is long; no catalytic method is used. Plant and animal oils as well as waste oils from the food industry are utilized. The yield is higher than that of the catalytic process, the reaction temperature is low, and the process is simple, safe, and efficient ； Methanol requires supercritical treatment, is used in large quantities, and the process takes a relatively long time. IV. Analysis of the development prospects for biodiesel 1. The industrialization prospects of biodiesel in China **The development plan for the 10th Five-Year Plan calls for the development of various alternatives to petroleum, and it designates the development of bio-liquid fuels as a key direction for industrial growth.** The biodiesel industry has received support from the leaders of the State Council as well as various departments such as the Planning Commission, the Economic and Trade Commission, and the Ministry of Science and Technology, and it has been included in relevant plans. 　　With the accelerating trend toward diesel-powered vehicles, demand for diesel will continue to rise in the future, and this demand is set to maintain a long-term upward trajectory. Meanwhile, the global supply of diesel is severely insufficient, leaving ample room for the development of biodiesel. Experts predict that by 2010, the share of diesel in global automotive fuel consumption will rise from 38% to 45%, leading to a severe shortage of diesel supply; this creates ample opportunities for the development of biodiesel. Developing the biodiesel industry can also promote the economic and social development of rural areas in China. Developing the production of biodiesel from oilseed plants can pave the way for transforming agricultural products into industrial goods, thereby helping to enrich and strengthen farmers; it is also conducive to adjusting the agricultural structure and increasing farmers’ incomes. 　　The issue of supply and demand balance for diesel will also remain a key focus in the development of China’s oil market for a long time to come. It is estimated that by 2010, China’s demand for diesel will exceed 100 million tons, representing a 20% increase compared to 2006 ； By 2015, market demand is expected to reach around 130 million tons. In recent years, despite continuous technological upgrades by refining and chemical enterprises that have led to an increasing production ratio of diesel to gasoline, this still fails to meet the required consumption ratio of diesel to gasoline. Currently, the ratio of diesel to gasoline in production is around 1.8, while the market consumption ratio is above 2.0; in provinces and regions such as Yunnan, Guangxi, and Guizhou, this consumption ratio is even above 2.5. With the acceleration of western development and the successive launch of major infrastructure projects for the national economy, the contradiction between diesel and gasoline consumption has become more pronounced than ever before. Therefore, the development of biodiesel not only aligns with the current trend in the petrochemical industry to adjust the oil product structure and increase the ratio of diesel to gasoline, but it also holds great significance. 　　The development and utilization of biodiesel in China are still in their initial stages. To reduce the cost of biodiesel overall and enable it to play a greater role in the transformation of China’s energy structure, it is necessary to move toward a model based on large-scale production, to adopt intensive management practices, and to develop an industrialized sector – only in this way can a development path for biodiesel that suits China’s national conditions be pursued. As reform and opening up progress further, within the context of global economic integration and China’s accession to the WTO, China’s economic level will continue to rise, leading to an increasing demand for energy. Once the research findings related to biodiesel are transformed into practical applications and industrialized, its uses in diesel engines, diesel power plants, air conditioning systems, and as fuel in rural areas will be extremely broad. 　　Biodiesel has advantages such as high efficiency and low pollution. It can be extracted from food waste oils (waste animal and plant fats). This type of diesel contains virtually no sulfur or aromatic compounds, and it has a high oxygen content, which facilitates proper combustion in internal combustion engines and thus reduces the emission of harmful substances in exhaust gases. Compared to conventional diesel, biodiesel is biodegradable, reducing air toxicity by 90% and the risk of cancer by 94%. It also does not release sulfur, which helps to minimize the occurrence of acid rain. China will also vigorously promote the use of biodiesel during the 11th Five-Year Plan period. In Shandong and Anhui, there is already experience in adding 10% biodiesel to diesel fuel. 　　Energy is related to the field of **security; environmental protection is an issue of concern to all of humanity. Agriculture is an industry that China must never neglect, and high-tech is a powerful driving force for societal development. Energy, environmental protection, agriculture, and high technology are the advantages and unique aspects of biodiesel projects. Broad prospects for industrial development, a strong policy and legal support framework, unique production processes and technologies, as well as stable growth in profits, all provide guarantees for the bio-oil industry. 　　As the production technologies for biodiesel continue to develop, along with the introduction of various supportive policies, the investment environment for biodiesel will improve further. There will be more and more biodiesel manufacturers, and as a result, the demand for biodiesel production equipment will also increase. It is understood that some well-known biodiesel manufacturers in regions such as Sichuan and Fujian build production lines with an annual output of tens of thousands of tons for their clients; the cost of equipment alone amounts to seven or eight million yuan, and an additional two million yuan is charged as a technical service fee. This results in extremely high profits. Therefore, operating in the biodiesel industry while also engaging in the production, sales, and technical services related to biodiesel production equipment can generate substantial profits for businesses. V. Hot Topic: How to overcome the cost barrier of biodiesel? 　　The main problem with the current extensive development of biodiesel is its high production cost, which renders it uncompetitive. Taking into account the current development trends in biodiesel production as well as China’s national conditions, cost reduction can be achieved through the following approaches. 　　1. Reducing production costs 　 Compared to edible animal and plant oil raw materials, the prices of the following biodiesel raw materials are significantly lower. (Table 8.12) Table 8.12 Sources of biodiesel raw materials and explanations. Source of raw material: Explanations: By-products from the refining of animal and plant oils. These are by-products resulting from the degumming and deacidification processes of plant oils such as rapeseed oil, soybean oil, cottonseed oil, and palm oil, which are used in large quantities for food purposes. Biodiesel is produced through processes such as hydrolysis and distillation, and its price is similar to that of conventional diesel. Waste oil recovered from the food service industry includes various oils that have deteriorated due to oxidation after being used for frying. Waste oil recovered from residues left after dining also includes oil recovered from washing wastewater. Animal and vegetable oils recovered from other industries: some industries recover oil during the degreasing process, while waste oil is collected from landfills; after appropriate treatment, it becomes harmless recycled oil. 　　2. Improve technical levels 　　(1) Adopt processes suitable for different raw materials to increase product recovery rates 　　Different processes should be chosen for various raw materials in order to enhance the yield and production of biodiesel. For example, in the case of oxidized and degraded waste oil recovered from frying, where the content of free fatty acids is low and the main components are triglycerides, the following processing sequence should be chosen: pretreatment ； Methanol pre-esterification ； Methanolysis, distillation. If the traditional fatty acid production process is used, involving hydrolysis followed by esterification, it not only increases energy consumption but also generates a large amount of wastewater, resulting in a lower yield. For the residues resulting from the alkaline refining of vegetable oils, saponification is first carried out to convert the triglycerides in these residues into sodium soaps ； Then dehydrate ； Finally, direct esterification and separation using sulfuric acid and methanol are carried out, followed by washing and dehydration to obtain biodiesel. 　　(2) Comprehensive utilization For most waste animal and vegetable oil raw materials, the metholysis reaction can be used to convert the triglycerides contained in them into methanol and glycerin. The aqueous layer at the bottom after this reaction is rich in glycerin, and industrial glycerin can be obtained through appropriate separation and purification techniques. Furthermore, crude methyl esters often require vacuum distillation to produce high-quality biodiesel; the distillate is the main product – biodiesel – while the residue, known as \"vegetable pitch,\" can be further used to make casting binders and building waterproof coatings. For crude oils rich in phytosterols, this distillation residue is also rich in phytosterols and can be used as a raw material for producing sterols, which find wide applications in industries such as pharmaceuticals, cosmetics, and food. 　　(3) Using enzyme-catalyzed technology to improve biodiesel yield. Compared with traditional chemical catalytic methods, enzyme-catalyzed esterification is milder and more efficient in its reaction with methanol; it allows for the use of less methanol and simplifies the process. It significantly reduces energy consumption and wastewater generation, facilitates the recovery of glycerol, and increases the yield of biodiesel. Currently, enzyme catalysis is developing rapidly, with an increasing number of methods to reduce the production costs of enzymes. For example, catalytic enzymes that are resistant to methanol and highly active can be selected through genetic engineering; they are easy to immobilize and can be reused repeatedly. Another approach is to use cellular enzymes, which are easy to produce, cost-effective, and have high catalytic efficiency; they hold promise for industrial trial operation in the near future. 　　3. **Policy support** 　　The government should provide strong support for the biodiesel industry by offering appropriate financial subsidies and tax incentives, so as to make biodiesel production more competitive and to pursue a development model based on the partnership between **, enterprises, farmers, banks, and technology ； At the same time, **the relevant authorities should formulate development plans for biodiesel as soon as possible, promote its entry into the automotive fuel market, actively develop the consumer market for biodiesel, and create a ‘aircraft carrier’ for the biodiesel industry so as to take advantage of scale advantages and supply the market with large quantities of inexpensive biodiesel. 　　In summary, replacing petroleum with biomass feedstocks to produce fuels and chemical products represents a significant shift in the feedstock strategy. From a long-term development perspective, developing the bio-refining industry is also a way to implement China’s scientific development concept of putting people first and pursuing comprehensive, coordinated, and sustainable development. Let us join hands to contribute to the development of China’s biodiesel industry, enabling this emerging sector to thrive and play its vital role in the country’s economic growth.