As the first batch of pilot units of circular economy in China, Jiangsu has made great efforts to develop rural biogas projects with the development of circular agriculture as the starting point, and achieved remarkable results. Biogas, as a green energy source, provides new opportunities for rural development and farmers' income increase. It will play a greater role in saving resources, developing ecological agriculture, preventing rural environmental pollution and building a new socialist countryside. However, the achievements of biogas project construction in Jiangsu province have just begun to appear, and there are still obstacles such as insufficient publicity, insufficient investment and not new mechanism, which require governments at all levels to take effective measures to vigorously promote.
First, the development status quo
Rural biogas projects organized by Jiangsu include rural household biogas, biogas treatment in large and medium-sized livestock farms and biogas digesters for purifying domestic sewage.
At present, there are nearly 65,438+rural household biogas projects, of which 30,000 were newly built in 2005, mainly distributed in five cities in northern Jiangsu and parts of central Jiangsu, including those built in the 1970s and 1980s. The total number of household biogas digesters in the province reached 447 thousand. There are 28 biogas projects 128 in large and medium-sized livestock and poultry farms, with a total pool capacity of 33,000 cubic meters, and the annual treatment of livestock and poultry manure10.49 million tons, including 55 large biogas projects, with pool capacity exceeding 100 cubic meters, mainly distributed in Suzhou, Wuxi, Nanjing, Xuzhou, Lianyungang and other places. In addition, there are 17900 biogas purification projects for domestic sewage in towns and villages in the province, with a total tank capacity of 549,900 cubic meters, which can treat domestic sewage of nearly 2 million people, mainly distributed in southern Jiangsu, Huai 'an and Taizhou.
Jiangsu biogas construction project conforms to the actual requirements of Jiangsu's development, gives full play to its scientific and technological advantages, and is an important step in developing circular economy, providing clean energy and improving rural environment.
& nbsp1.Biogas is a clean and environmentally friendly energy suitable for rural resources and environment in Jiangsu.
The calorific value of biogas is quite high, generally 20934-25 12 1 kJ/m3, and the highest combustion temperature can reach 1400℃, which is higher than the calorific value of city gas. It is a high-quality fuel. Biogas is a renewable pollution-free energy. As long as the sun and living things exist, biogas can be produced repeatedly. Although trace amounts of carbon monoxide and hydrogen sulfide are toxic, they can be detoxified by oxidative combustion, so the generated biogas will not cause pollution. On the contrary, the pathogens of infectious diseases-human and animal manure and urban organic garbage, can kill germs and parasite eggs through anaerobic fermentation and precipitation in biogas digesters, thus effectively preventing the spread of diseases. Biogas has a wide range of raw materials and can be obtained locally. Human and animal manure, crop straw, plant litter, sludge garbage, industrial waste residue containing organic matter, wastewater, etc. It can be used as fermentation raw material for biogas production, without special production conditions, and biogas can be produced when the pool temperature is stable above 10℃. Jiangsu Province belongs to subtropical and warm temperate zone, with an annual average temperature of 13℃- 16℃. As long as we pay attention to the overwintering management of biogas digesters, we can produce gas all year round. Jiangsu raises about 50 million pigs and 800 million poultry every year, producing tens of thousands of tons of feces every year. At present, most of these feces are not effectively utilized, which not only loses a lot of valuable resources, but also seriously pollutes the rural environment due to direct discharge. Through the construction of biogas project, we can turn waste into treasure, produce a large number of high-quality gas instead of burning straw and coal, and improve the quality of life of farmers. Farmers build an 8 cubic meter biogas digester, which can produce 300 cubic meters of biogas every year, which can basically meet the living energy demand of a family of 4-5, and save fuel and electricity about 300 yuan. Jiangsu has built 654.38 million biogas digesters, which not only improves the quality of life of farmers, but also saves a lot of energy expenditure.
& ampNbsp2。 Biogas engineering is helpful to ecological agriculture and rural environmental construction.
Biogas is not only a high-quality and efficient clean fuel, but also the biogas slurry and biogas residue produced by it have a very wide range of uses. The fertilizer efficiency of biogas residue is more than 3 times that of common farmyard manure, which can effectively promote crop yield and improve product quality. Biogas slurry can be used for fertilization, fish and shrimp culture and seed soaking. By adopting the biological chain model of "pig-biogas-fruit", "pig-biogas-fish" and "pig-biogas-vegetable", the soil hardening caused by long-term use of chemical fertilizers was improved, the composition of organic fertilizer was obviously improved, the water pollution in rural areas was effectively controlled, and the quality of agricultural products was improved. It can be seen that biogas can not only solve rural energy problems, but also increase farmers' income.
& ampNbsp3。 Biogas is a reliable energy source with mature technology.
After more than 20 years of exploration, rural biogas technology has matured. In order to ensure the construction of one household and protect the interests of farmers, Jiangsu stipulates that the construction of rural biogas projects must implement relevant national or industry standards. The unified adoption of the "one pool and three reforms" model requires all localities to strictly follow these regulations and standards, study village by village, design house by house, and unify construction, so as to achieve one construction and one use, and effectively play an effective role in improving farmers' lives and promoting agricultural production.
Second, the current difficulties encountered in the development of biogas in Jiangsu
Developing biogas project can not only provide clean energy, but also contribute to ecological agriculture and rural environmental construction. Therefore, the development momentum of biogas in Jiangsu is good, but it is still in its infancy. Some of the 65438+ 10,000 biogas digesters that have been built are no longer used because of disrepair, and tens of thousands of biogas digesters that are still in use are just a spark for tens of millions of farmers, and have not become a prairie fire. At present, most of the biogas in Jiangsu is still limited to self-use and in the internal treatment stage, and biogas projects have not become one of the rural infrastructure. The development of biogas in Jiangsu mainly faces the following difficulties.
& nbsp1,farmers lack understanding of biogas technology.
In 1970s and 1980s, China also set off an upsurge of building biogas in rural areas. At that time, the main purpose was to solve the problem of fuel shortage. Due to the backward technology, the biogas produced has low purity and poor combustion effect, which can not effectively meet the needs of farmers' lives and achieve the ideal effect. Moreover, when the biogas slurry came out, due to lack of oxygen, farmers' safety awareness was not strong, and some poisoning deaths occurred. After the climax, a large number of biogas digesters were abandoned, resulting in a waste of manpower, financial resources and material resources. Now that the biogas digester has been rebuilt, most rural residents' understanding of the new biogas digester is still at the original level, and they are not familiar with the new construction technology and have concerns. In addition, we don't know much about the advantages of comprehensive utilization of biogas resources. Based on past experience, we are naturally not interested in new biogas construction projects, and some even have resistance and mistakenly think that they are new image projects.
& nbsp 2, lack of funds makes it difficult to fully promote it.
Biogas engineering construction is one of the important contents of new rural construction, and it is a popular project and a project to enrich the people. One of the important reasons is that it has not been fully promoted at present, and the lack of construction funds is one of the important reasons. Building a biogas digester is about 2000 yuan, which is not a small expense for rural residents in northern Jiangsu. Biogas construction projects, as rural infrastructure projects, need the support of the government. In 2004, Jiangsu won 8 million yuan for five cities in northern Jiangsu through the rural biogas national debt project, and at the same time, Jiangsu also spent 8 million yuan through the rural energy project of small public welfare facilities to support the construction of biogas digesters in pilot counties. However, the funds allocated to each pilot county are only 654.38 million yuan. According to the standard of 1 household subsidy 1000 yuan, a county can only build 100 biogas digesters at most. At the same time, farmers in poverty-stricken areas have low self-financing ability, few local supporting funds, and it is difficult to implement "one pool and three reforms" because of tight funds. For example, according to the current capital investment in Yancheng, it will take 20 years for the rural biogas penetration rate to reach 20%.
There is a shortage of construction funds, and special training funds are even more stretched. The shortage of funds has affected the popularization of technology. For example, the feed and discharge of the simplest biogas digester have certain requirements. If the fermentation raw materials contain antibiotics, insect repellents, pesticides and other substances, it will cause microbial poisoning of biogas and stop gas production. At the same time, if the fermentation broth is acidified (below PH 6.5), gas production will also stop. Insufficient training affects the efficiency of biogas use.
For example, in the next five years, household biogas digesters will be built 1 10,000, and about 2,000 large, medium and small biogas digesters will be treated, which requires a huge construction fund of 2.7 billion yuan. Such a huge capital demand, if the government can't invest, will seriously restrict the biogas industry in Jiangsu.
& nbsp 3, the post-service can't keep up.
"Three points to build a pool, seven points to manage", but most cities and counties tend to focus on construction rather than management, and technical services are not in place. The construction workers who build biogas digesters are highly mobile, and most young people in rural areas work in other places. The old people who stayed behind mastered the new technology slowly, and basically managed by feeling. They don't know how to deal with abnormal gas production or gas stop, and the risk factor is greatly improved when the displacement is large. At the same time, there are still few spare parts supply points for biogas digesters, which can not meet the needs of the masses to replace spare parts in time.
Third, suggestions for the further development of biogas
& nbsp1.Increase the propaganda of rural biogas work and popularize rural biogas knowledge.
It is difficult to carry out biogas in pilot cities and counties. Farmers lack understanding of the current biogas technology, and their thoughts are still in the 1970s and 1980s. It is extremely difficult to mobilize for large-scale promotion. To promote biogas construction in a large area, we should learn from the practices of pilot cities and counties and increase publicity. Make full use of radio, television, wall charts, books, slides and theatrical performances. Popularize biogas knowledge to farmers and convey the message of getting rich green. Leading farmers to visit and study biogas digesters, allowing farmers who have built biogas digesters to show their views, and letting farmers who have not built biogas digesters deepen their understanding of biogas digesters, naturally there is an inherent demand for building biogas digesters. Make full use of the demonstration role of biogas pilot counties and cities to achieve the effect of point to area,
& nbsp 2, it is no longer limited to solving energy problems, but we should vigorously develop rural circular economy by using biogas.
With the development of agricultural production and the improvement of farmers' income level, the problem of household energy shortage has been alleviated to a certain extent, and solving the energy problem should not be the single goal of developing rural biogas. Make use of rural biogas, comprehensively utilize biogas slurry and biogas residue according to local conditions, develop circular economy, maximize the allocation efficiency of resources and environment, organically combine the adjustment of agricultural production structure, increase farmers' income with the prevention and control of agricultural non-point source pollution and improvement of ecological environment, gradually realize the rationalization of agricultural industrial structure, ecological technology, clean production and high-quality products, promote the sustainable development of agriculture and rural economy, and make greater contributions to the construction of new countryside.
& ampNbsp3。 Increase financial input and coordinate fund management.
Rural biogas is a public welfare undertaking that benefits the people. In view of the current shortage of funds, it is obviously not enough to rely solely on the input of farmers who have not yet become rich. It is necessary for the government to reform and optimize the agricultural investment system, increase financial input and coordinate fund management. In 2004, the government's financial funds for supporting agriculture reached11300 million yuan, but the investment in agricultural projects was concentrated in different departments and the policies were not unified. For example, farmers invest money from many departments to build biogas, so that some places are adjacent to two villages, one village has subsidies for building biogas, and the other village does not, which affects farmers' enthusiasm for developing biogas resources in developing circular economy. On the basis of unified planning, biogas construction should be managed and supported by a department, with unified policies and comprehensive promotion.
& ampNbsp4。 Strengthen basic management and provide follow-up services.
Popularizing rural biogas on a large scale requires a stable technical service team. The government should further strengthen team building and training, strengthen vocational skills training and appraisal, promote the vocational qualification certificate system, and implement construction technicians with certificates. Relevant departments should follow up the pilot projects in a timely manner and study and solve existing problems in a timely manner; It is necessary to strengthen equipment management and daily maintenance, help farmers to enhance their safety awareness, provide timely and thoughtful services for farmers to build and use biogas, and ensure that biogas digesters play their due role. Effectively improve the quality of life of farmers and avoid affecting the quality of daily life of farmers due to lack of services.
& nbsp 5, government-led, changing government-led to farmers' consciousness.
Biogas engineering construction is to do practical things and do good deeds for farmers, but to be truly welcomed by farmers, it is necessary to change the situation of government-led, government-built and farmers watching. "Three changes to one pool" should conform to the actual life and production of farmers. For example, farmers who don't keep livestock or keep too few livestock are not suitable for building biogas digesters because they don't have stable manure resources, and farmers who lack labor resources in rural areas are not suitable for building biogas digesters. If we arbitrarily approve and subsidize the application for biogas digesters for the purpose of increasing the proportion of farmers, it will inevitably lead to the abandonment of biogas digesters. In the process of developing rural biogas industry, the government can only play the role of leading, supporting and serving, but cannot act as a substitute. Only when the rural biogas industry in Jiangsu becomes the conscious demand of farmers can it flourish and make practical contributions to building a new socialist countryside.