Biodiesel refers to a renewable diesel fuel that can replace petrochemical diesel oil by using oil crops, wild oil plants, engineering microalgae and other aquatic plant oils, as well as animal oils and restaurant garbage oils as raw materials. Biodiesel is a kind of biomass energy, which is a monoalkyl ester of long-chain fatty acids obtained by pyrolysis of biomass and other technologies. Biodiesel is a mixture of complex organic components with extremely high oxygen content. These mixtures are mainly some organic compounds with high molecular weight, including almost all kinds of oxygen-containing organic compounds, such as ethers, esters, aldehydes, ketones, phenols, organic acids and alcohols. Biodiesel is a kind of high-quality clean diesel oil, which can be extracted from various biomass, so it can be said to be an inexhaustible energy source, and it is expected to replace oil as an alternative fuel in today's increasingly exhausted resources.
[ Edit this paragraph] Features:
1) The water content is high, up to 31%-45%. Moisture is beneficial to reduce the viscosity and improve the stability of oil, but it reduces the calorific value of oil;
2) The pH value is low, so the storage device is preferably made of acid-resistant materials;
3) The density is higher than that of water, and the ratio with water is about 1.2;
4) It has the tendency of "aging", and the heating temperature should not exceed 81℃, so it should be kept away from light and air.
5) Good lubrication performance.
6) Excellent environmental protection characteristics: low sulfur content, low emission of sulfur dioxide and sulfide, 98% biodegradability of biodiesel, and the degradation rate is twice that of ordinary diesel, which can greatly reduce the environmental pollution caused by accidental leakage;
7) Good low-temperature engine starting performance;
8) Good safety performance: high flash point and safe transportation, storage and use;
[ Edit this paragraph] The status quo of biodiesel industry
Biodiesel is a clean and renewable energy. It is a liquid fuel made from oil crops such as soybean and rapeseed, oil palm and Pistacia chinensis, oil aquatic plants such as engineering microalgae, animal fat, waste catering oil, etc. It is a high-quality substitute for petroleum diesel. Biodiesel is a typical "green energy", and vigorously developing biodiesel has important strategic significance for sustainable economic development, promoting energy substitution, reducing environmental pressure and controlling urban air pollution.
Looking at the developed countries in the world, such as the United States, Germany and Japan, to the less developed South Africa, Brazil and South Korea, and to the developing India and Thailand, they have provided good references in the aspects of international policy system, technical perfection, equipment construction and vehicle manufacturing, paving the way for China to take the road of oil substitution with China characteristics. Especially Brazil's experience, has more practical significance.
Biodiesel is a new industry in China, showing many market characteristics that the new industry had in the early stage of industrialization. Many enterprises are attracted by the business opportunities highlighted by the dual "concepts" of green energy and agriculture-supporting industries, and have entered the industry one after another. Some people describe the current state of biodiesel as "like mushrooms after rain". By the end of 2117, there were more than 2,111 large and small biodiesel production plants in China, and the establishment and approval of similar projects in various places continued. There is a bigger threat from abroad. Some foreign companies have strong financial strength, mature production technology and high degree of industrialization, so they can take advantage of economies of scale to gain cost advantages and have stronger comprehensive ability to seize raw material bases and market share
From the perspective of future development, the buyers of biodiesel mainly include oil refineries, power plants, shipping companies and middlemen in the circulation field. The demand for biodiesel is increasing constantly. It is predicted that by the year 2111, the demand for biodiesel in China will reach 21 million tons/year. According to the national long-term plan for renewable energy, the production capacity at that time will be 211,111 tons/year. The contrast between demand and output will lead to the situation that the supply of products is in short supply. When people know more about the excellent performance of biodiesel, their acceptance will be greater, and the market demand will continue to increase. Strong market demand and limited production capacity reduce the bargaining power of buyers. At the same time, it also puts forward higher requirements for biodiesel production enterprises, and should increase investment in technological innovation and continuously improve the quality of oil products in order to maintain a good quality image of biodiesel.
With the deepening of reform and opening up, China's economic level will be further improved in the process of global economic integration, and its demand for energy will increase. As long as the research results on biodiesel are transformed into productivity and industrialized, its application prospects in diesel engines, diesel power plants, air-conditioning equipment and rural fuels are very broad.
[ Edit this paragraph] Production method
The method of synthesizing biodiesel from oil raw materials; Biodiesel prepared from animal oil and its preparation method; Additives for biodiesel and biofuel oil; Emulsifier for light diesel oil produced from waste animal and vegetable oils and its application; Low-cost and pollution-free biomass liquefaction process and device; Low-energy-consumption biomass pyrolysis process and device; A method for preparing biodiesel by rapid pyrolysis of microalgae; Depolymerization kettle for extracting gasoline and diesel oil from waste plastics, waste oil and waste vegetable oil residues, method for preparing fuel gas by biomass gasification and gasification reaction device; Process for extracting petroleum products from vegetable oil residues; A method for preparing synthetic gas by plasma pyrolysis of gasified biomass, and a method for preparing biodiesel by hydrolyzing heterotrophic algae with amylase; A method for producing liquid fuel from biomass; The technological method of producing fuel oil from vegetable oil leftovers, the method of preparing bio-oil from biomass hydrolysis residues, and the production method of extracting gasoline and diesel oil from vegetable oil residues; Device and method for regenerating fuel oil from waste oil; The method of removing colloid from FCC diesel oil; A new environmentally-friendly process for refining fuel oil from waste rubber (waste plastics and waste engine oil), and a chemical refining method for removing total oxidized insoluble matter and colloid from diesel oil; Additives to prevent discoloration and gelation of diesel oil and gasoline; Flocculation separation treatment method of waste lubricating oil.
Simple technological process:
Biodiesel is an alternative diesel fuel composed of fatty acid alkyl monoesters from vegetable oil or animal fat. At present, most biodiesel is produced by soybean oil, methanol and an alkaline catalyst. However, most cheap oils that are not easily digested by human body can be converted into biodiesel.
Brief description of process flow:
(1) Physical refining: firstly, oil is hydrated or treated with phosphoric acid to remove phospholipids, colloid and other substances). Preheat, dehydrate and degas the oil into the deacidification tower, maintain the residual pressure, and introduce excessive steam. At the steam temperature, the free acid and steam are distilled out together, and after condensation and precipitation, the net loss except free fatty acid can be removed, and the free acid in the oil can be reduced to a very low amount, and the pigment can also be decomposed to make the color lighter. Crude fatty acid methyl ester was produced by simultaneous esterification and alcoholysis of various waste animal and vegetable oils under the action of self-developed DYD catalyst. (2) Pre-esterification of methanol: firstly, the oil is hydrated and degummed, and floccules formed during hydration such as phospholipids and gums are removed by a centrifuge, and then the oil is dehydrated. Excess methanol is added to raw oil, and pre-esterification is carried out in the presence of acidic catalyst to convert free acid into methyl ester. Methanol water is distilled off, and after fractionation, C12-16 methyl palmitate and C18 methyl oleate are separated without free acid.
(3) ester exchange reaction: the pretreated oil and methanol, together with a small amount of NaOH as catalyst, are subjected to ester exchange reaction at a certain temperature and atmospheric pressure, that is, methyl ester can be generated, and a two-step reaction is adopted to continuously remove glycerol generated in the initial reaction through a specially designed separator, so that the ester exchange reaction can be continued.
(4) gravity precipitation, water washing and stratification.
(5) Separation of glycerol and acquisition of crude methyl ester.
(6) Dehydration of water, release of methanol, removal of catalyst and acquisition of refined biodiesel.
the whole technological process is closed-loop, and all raw materials are comprehensively utilized to realize clean production. Roughly described as follows: raw material pretreatment (dehydration, deodorization and purification)-reaction kettle (adding alcohol+catalyst+71℃)-stirring for 1 hours-precipitation, separation and impurity removal-alcohol recovery-filtration.
Biodiesel is a kind of high-quality clean diesel oil, which can be extracted from various biomass, so it can be said to be an inexhaustible energy source, and it is expected to replace petroleum as an alternative fuel in today's increasingly exhausted resources.
diesel is the main power fuel for many large vehicles, such as trucks, diesel locomotives and generators. It has the advantages of great power and low price. There is a great demand for diesel in China, and the main problem of diesel application is "black smoke". We often see black smoke trucks on the road. The main cause of black smoke is incomplete combustion, which causes serious air pollution, such as a large amount of particulate dust and high CO2 emission. According to the American Fuel Institute, air pollution caused by engine fuel combustion has become the main problem of air pollution. For example, nitrogen oxides account for half of emissions from other industries, carbon monoxide accounts for two-thirds of emissions from other industries, and toxic hydrocarbons account for half of emissions from other industries. Nitrogen oxides and sulfides discharged from the tail gas can combine with water in the air to form acid rain. Too much carbon dioxide and carbon monoxide in the tail gas will raise the atmospheric temperature, which is often called the "greenhouse effect". In order to solve the problem of tail gas pollution of fuel and the worsening environmental pressure, people began to study the use of other fuels such as fuel alcohol instead of gasoline. At present, fuel alcohol has occupied a considerable proportion in North America such as the United States and Canada and South American countries such as Brazil and Argentina, and cars equipped with fuel alcohol engines have been put on the market. Fuel alcohol is not suitable for most high-powered vehicles that need diesel fuel, such as buses, diesel locomotives and agricultural vehicles such as tractors. Moreover, the tail gas pollution caused by diesel is much greater than that caused by gasoline, so people have developed a substitute for diesel-biodiesel.
In fact, Diesel, the inventor of the engine, said in the report of the Missouri Engineering Conference in the United States in 1912 that "using rapeseed oil as engine fuel does not seem to have much significance today, but it will become as important as oil and coal in the future". In 1983, American scientists first used rapeseed oil methyl ester in engines and burned it for 1111 hours. The renewable fatty acid monoester is defined as biodiesel. In 1984, scientists in the United States and Germany studied the use of fatty acid methyl ester or ethyl ester instead of diesel oil as fuel, that is, using fatty acid monoesters from animals or plants, including fatty acid methyl ester, fatty acid ethyl ester and fatty acid propyl ester, to replace diesel oil for combustion. Compared with traditional petroleum diesel, biodiesel has the following advantages: < P > Using renewable animal and plant fatty acid monoesters as raw materials can reduce the demand and import of petrochemical fuel oil; Environment-friendly, the emission of toxic organic matter in the tail gas of biodiesel is only one tenth, the particulate matter is 21% of that of ordinary diesel, the emission of carbon monoxide and carbon dioxide is only 11% of that of petroleum diesel, and there is no emission of sulfide, lead and toxic substances; Blending biodiesel can reduce the sulfur concentration from 511PPM(PPM to 5PPM.
there is no need to replace the engine, and the engine is protected.
[ Edit this paragraph] Application of biodiesel in various countries in the world
At present, all countries in the world, especially developed countries, are committed to developing efficient and pollution-free biomass energy utilization technologies. Europe has become the main producer of biodiesel in the world. The United States, Italy and France have successively built dozens of biodiesel production devices.
the United States is the first country to study biodiesel. The total production capacity is 1.3 million tons. The tax rate for biodiesel is 1%. The 611,111-kilometer driving test conducted by the United States in Yellowstone National Park showed no coking phenomenon, and the air pollutant emission was reduced by more than 81%. Moreover, the use of biodiesel also attracted brown bears from 311 kilometers away to the park. B21 in the United States uses 21% biodiesel, and the emission of exhaust pollutants can be reduced by more than 51%. In 1992, both the US Energy Department and the Environmental Protection Agency proposed biodiesel as a clean fuel. In 1999, US President Bill Clinton signed a decree to develop biomass energy, among which biodiesel was listed as one of the key clean energy sources, and the state did not levy taxes on biodiesel. In 1995, Japan began to study the production of biodiesel from the leftover frying oil in restaurants. In 1999, an industrial experimental device with 259 liters/day of frying oil was established to produce biodiesel, which can reduce the raw material cost. At present, the annual output of biodiesel in Japan can reach 411,111 tons.
At present, Germany has eight biodiesel factories, more than 311 biodiesel gas stations, and has set standards for biodiesel, which is tax-free. In 2116, the output of biodiesel reached 1 million tons.
France, Italy and other European countries have established biodiesel enterprises. The French Citroen Group has carried out the experiment of biodiesel, and through the combustion test of 11111 kilometers, it is proved that biodiesel can be used in ordinary diesel engines. Its standard is to add 5% biodiesel to ordinary petroleum diesel.
It can be predicted that biodiesel, as an important clean fuel, will play an important role in the driving of large vehicles.
[ Edit this paragraph] ■ Analysis of the development status and industrialization prospect of biodiesel in China
The development status of biodiesel in China:
The Chinese government has formulated some policies and measures to solve the problems of energy conservation, substitution and environmental protection, and some scholars and experts have already devoted themselves to the research and advocacy of biodiesel. Although the research and development of biodiesel in China started late, it developed rapidly, and some scientific research achievements have reached the international advanced level. The research content involves the distribution, selection, cultivation, genetic improvement, processing technology and equipment of oil plants. At present, all aspects of research have achieved phased results, which will undoubtedly contribute to the further research and development of biodiesel in China. It can be predicted that in 2-3 years, China's research in this field will make a breakthrough and reach the practical level.
Academician Min Enze, a famous scholar, first clearly put forward the topic of developing clean fuel biodiesel in his book Green Chemistry and Chemical Industry: the former Ministry of Machinery Industry and the former China Petrochemical Corporation set aside special funds for the project in the 1981s, and the project was undertaken by Shanghai Internal Combustion Engine Research Institute and Guiwai I Mountain Agricultural Machinery Co., Ltd. for 11 years, and invited Zhan Yonghou, an expert from China Petrochemical Academy, to do a lot of basic experiments and explorations; Mr. Shi Delu of China Agricultural Engineering Research and Design Institute also carried out the experiment of biodiesel in 1985. China-Europe cooperative research project undertaken by Liaoning Energy Research Institute also involves biodiesel; The University of Science and Technology of China, Henan Institute of Science and Army Chemistry and other units have also made different degrees of research on biodiesel.
The systematic research began with the key scientific research project of the Eighth Five-Year Plan of China Academy of Sciences: "Research and application technology of fuel oil plants", and completed the investigation of fuel oil plant resources and the research on cultivation technology in Jinsha River basin.