Biodiesel production status at home and abroad
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Biodiesel production status at home and abroad Biodiesel 1. Characteristics of biodiesel Biodiesel is a clean and safe new fuel made from renewable resources such as vegetable fats or animal fats that can replace petrochemical diesel. The main ingredients are ester compounds formed by long-chain saturated and unsaturated fatty acids such as palmitic acid, stearic acid, oleic acid, and linoleic acid, and methanol or ethanol. Biodiesel is renewable, easily biodegradable, has low combustion pollutant emissions, and low greenhouse gas emissions. Biodiesel has similar properties to petrochemical diesel and has unparalleled advantages: (1) Has excellent environmental protection properties. The main reason is that the low sulfur content in biodiesel results in low sulfur dioxide and sulfide emissions, which can be reduced by about 30% (70% with a catalyst); biodiesel does not contain aromatic alkanes that pollute the environment, so the exhaust gas is less harmful to the human body than oil. Tests show that compared with petrochemical diesel, the use of biodiesel can reduce air toxicity by 90% and reduce cancer rates by 94%; due to the high oxygen content of biodiesel, it emits less smoke when burned, and carbon monoxide emissions are reduced by about 10% compared with diesel (95% with a catalyst); biodiesel is highly biodegradable. (2) Has better low-temperature engine starting performance. Without additives, the cold filter plugging point reaches - 20 ℃. (3) Has good lubrication performance. The fuel injection pump, engine block and connecting rod have low wear rate and long service life. (4) Has good safety performance. Since the flash point is higher than that of petrochemical diesel, biodiesel is not considered a hazardous material. Therefore, the advantages in transportation, storage, and use are obvious. (5) Has good combustion performance. The high cetane number makes it combustible better than diesel, and the slightly acidic combustion residue extends the service life of the catalyst and engine oil. (6) It has renewable properties. As a renewable energy source, unlike oil reserves, its available supply will not be exhausted through the efforts of agricultural and biological scientists. (7) There is no need to modify the diesel engine and it can be added directly for use. At the same time, there is no need to add additional refueling equipment, storage equipment and special technical training for personnel. (8) When biodiesel is blended with petrochemical diesel in a certain proportion, it can reduce fuel consumption, improve power performance, and reduce exhaust pollution. 2. The main production methods, raw materials and quality standards of biodiesel. The preparation methods of biodiesel include direct mixing method, microemulsion method, high temperature pyrolysis method, transesterification method and supercritical methanol method. At present, biodiesel is mainly produced by chemical methods, that is, animal and vegetable oils and low-carbon alcohols such as methanol or ethanol are used to conduct transesterification reactions under acidic or alkaline catalysts and high temperatures (230-250°C) to generate corresponding fatty acid methyl esters or ethyl esters, which is biodiesel. However, this method has the following shortcomings: the process is complex, alcohol must be excessive, and subsequent processes must have corresponding alcohol recovery devices, which consumes high energy; the esterification product is difficult to recover and the cost is high; waste alkali liquid is discharged during the production process. For this reason, people have begun to pay attention to the bioenzymatic synthesis of biodiesel technology, which uses animal and vegetable oils and low-carbon alcohols to perform transesterification reactions through lipases to prepare corresponding fatty acid methyl esters and ethyl esters. Enzymatic synthesis of biodiesel has the advantages of mild conditions, small alcohol consumption, and no pollution emissions. However, there are currently some problems that need to be solved when using biological enzymatic methods to prepare biodiesel: lipase has a good catalytic effect on the esterification or transesterification of long-chain fatty alcohols, but the conversion rate of short-chain methanol and ethanol is low, and short-chain alcohols are toxic to the enzyme, and the service life of the enzyme is short; the by-products glycerol and water are difficult to separate and recover, which not only inhibits the product, but also glycerol is toxic to the immobilized enzyme, making the immobilized enzyme short-lived. However, it is reported that Tsinghua University’s bioenzymatic biodiesel production has been successful in pilot testing, and the biodiesel yield in the pilot plant using the new process has reached more than 90%. The technical indicators of the pilot product meet the biodiesel standards of the United States and Germany, and meet China's No. 0 premium diesel standard. This provides a strong basis for the industrialization of bioenzymatic production of biodiesel. Biodiesel raw materials: (1) Grease: Soybean oil, corn oil, rapeseed oil, cottonseed oil, sunflower seed oil, safflower seed oil, tallow, lard, cooking oil and other vegetable oils or animal fats. (2) Alcohols: methanol, ethanol (alcohol) or isoalcohol, etc. ； catalyst: Sodium hydroxide, potassium hydroxide, etc. The quality standards for biodiesel have not yet been introduced in China. Generally, the quality standards of European and American countries are temporarily adopted.: Table 1 Biodiesel quality standards (Germany and the United States) Index units German DIN 51606 (1997) American ASTM6751 (2001) Density g/cm 3 0.875-0.90 -- Coking value CCR (100%) %Max 0.05 Max 0.050 Ash %Max 0.02 Max 0.020 Total sulfur %Max 0.01 Max 0.05 Cetane number - Min 49 Min 40 Flash point degrees Celsius Min 110 Min 100 Corrosion efficiency against copper 1 No. 3b max Kinematic viscosity, 40 0 C mm 2 /s (cSt) 3.5-5.0 1.9-6.0 Neutralization value mgKOH/g Max 0.5 Max 0.8 Free glycerin %Max 0.02 Max 0.02 Total glycerol%Max 0.25 Max 0.24 Cold filtering point (CFPP) Summer (Celsius) Max 0.0 -- Winter (Celsius) Max -15
Table 2 Biodiesel standard EN 14214 (Europe) Property detection method Extreme value unit Minimum value Maximum value Ester content EN 14103 96.5 % (m/m) Density； 15℃ EN ISO 3675 860 900 kg/m3 EN ISO 12185 Viscosity ； 40℃ ENISO 3104 EN 3105 3.5 5.0 mm2/s Flash point EN ISO 3679 120 ℃ Sulfur content EN ISO 20846 EN ISO 20884 10.0 mg/kg Carbon residue (10%, residual) EN ISO 10370 0.30 %(m/m) Cetane number EN ISO 5165 51 Sulfate ash ISO 3987 0.02 % (m/m) Water content EN ISO 12937 500 mg/kg Total pollutants EN 12662 24 mg/kg Copper strip corrosion (3 hr, 50℃) EN ISO 2160 1 Oxidation stability ； 110℃ EN 14112 6.0 hr Acid value EN 14104 0.50 Mg KOH/g Lodine value EN 14111 120 Giodine/100g Linolenic acid content EN 14103 12 % (m/m) FAME content with ≥4 double bonds 1 % (m/m) Methanol content EN 14110 0.20 %(m/m) Monoglyceride content EN 14105 0.80 %(m/m) Diglyceride content EN 14105 0.20 %(m/m) Triglyceride content EN 14105 0.20 %(m/m) Free glycerol EN 14105, EN 14106 0.02 %(m/m) Total glycerol EN 14105 0.25 % (m/m) Alkali metal (Na+K) EN 14108, EN 14109 5.0 mg/kg Alkali metal (Ca+Mg) PrEN 14538 5.0 mg/kg Phosphorus content EN 14107 10.0 mg/kg 1. Foreign biodiesel production and application status 20 In the 1990s, as the two major problems of environmental protection and petroleum resource depletion attracted more and more attention, especially in the United States and Germany, biodiesel has become a hot spot in the research and development of new energy. Western advanced * * Attaching great importance to development and production, biodiesel has quickly become a highlight of the new economic industry. The main raw materials for biodiesel production are soybeans, rape, castor, palm oil, waste oil, etc.; the main application forms are B5, B10~B20, and B100. Currently, there are 4 biodiesel production plants in the United States with a total capacity of 300,000 t/a. American Biofuels (ABF) Co., Ltd. is building the largest biodiesel production facility in the United States in California, with a designed production capacity of 35 million gallons/a (approximately 120,000 t/a). In order to reduce the device's footprint and investment and operating costs, the device adopts a continuous flow process. In the construction of the device, ABF's patented unit reactor/separator is used. The production capacity of each unit reactor/separator is 2.5 million gallons/a. This unit component is very easy to install and can be expanded according to market demand. The plant started producing biodiesel in 2003. The European Union recently issued two new directives to promote the application of biofuels in the automotive fuel market, which will further promote the development of the European biodiesel industry. The sales proportion of EU biodiesel in European automotive fuels will increase from US$504 million in 2000 to US$2.4 billion in 2007, and the annual growth rate is expected to reach 25%. Germany currently has 8 biodiesel production plants and more than 300 biodiesel filling stations. The production of biodiesel in 2003 was 500,000 t/a, and will soon reach 900,000 t/a. And the biodiesel standard DIN V51606 has been formulated, and there is no tax on biodiesel. France has 7 biodiesel production plants with a total capacity of 400,000 t/a. The usage standard is to add 5% biodiesel to ordinary diesel, and the tax rate for biodiesel is zero. Italy has 9 biodiesel production plants with a total capacity of 330,000 t/a, and the tax rate for biodiesel is zero. Austria has three biodiesel production plants with a total capacity of 55,000 t/a, and the tax rate is 4.6% of petroleum diesel. Belgium has 2 biodiesel production plants with a total capacity of 240,000 t/a. British Biofuels will invest 21 million pounds (US$37.8 million) in Sirens, England, to build a biodiesel plant using soybean oil as raw material. The plant has a capacity of 250,000 t/a biodiesel, 19,600 t/a pharmaceutical grade and 2,700 t/a industrial grade glycerol, and 600 t/a potassium sulfate fertilizer. The device is scheduled to be put into production in the first quarter of 2005. The biofuel company also plans to build a second unit locally in 2005 to double the biodiesel capacity to 500,000 t/a. The company also plans to build three more units in the UK or other parts of Europe from 2007 to 2009, with a total capacity of 750,000 t/a. Finnish energy company Fortum will build a processing plant dedicated to the production of biodiesel in the southern Finnish city of Porvoo. The biodiesel processing plant will be put into operation in the summer of 2007. The processing plant extracts high-quality diesel from vegetable oils and animal fats and is expected to produce 170,000 tons of biodiesel per year. Europe Others * * The production volume of biodiesel in the Czech Republic and Slovakia is 100,000 t/a. Belgium 20,000 t/a (2001). Italy 125,000 t/a. Austria 25,000t/a. Asia * * A biodiesel industry is also emerging. Malaysia is 500,000t/a. Japan's biodiesel production capacity reaches 400,000 t/a. Thailand's biodiesel development plan was released in July 2001. Thai Petroleum Company promised to purchase 70,000 tons of palm oil and 20,000 tons of coconut oil each year and implement tax exemptions. Thailand's first biodiesel device has been put into operation. Global Bioenergy Company built the first biodiesel unit for The Gambia, which was put into operation in 2003. The biodiesel device can convert peanut oil into alcohol-based diesel fuel, which can be used directly in diesel engines or blended with hydrocarbon diesel fuel. Biodiesel is attractive in Gambia, peanut oil is cheap, diesel is expensive, Gambia * * Support the development of biodiesel. According to research and analysis by Freedonia Consulting Company in the United States, the demand for biodiesel will grow rapidly, with a growth rate of 30% by 2006, and the market value of biodiesel will increase from US$35 million in 2003 to US$130 million in 2006.