Studies on the Process and Facilities of Straw-Excrement Ferment Technology for Biogas and Biological-Organic Compound Fertilizer
|School||Henan Agricultural University|
|Course||Agricultural Biological Environmental and Energy Engineering|
|Keywords||straw and feces biogas biological-organic compound fertilizer process and equipment|
The wastes of the agricultural, the feces of the poultry and animals and the living garbage produced by people are the main resourceof the organic solid wastes.with human society scale unceasingly expands, economic increases and the improvement of people’s living quality and life level , the per capita quantity of organic solid wastes are on riseing around the world. The existence of organic solid wastes not only occupied a lot of land, and for lack of timely and effective treatment, which caused a series of serious environmental problems , such as water pollution, air pollution and so on. These organic solid wastes are the“resource“which were set in the wrong place, No matter regard it from the mineral nutrition of the plants or from the energy and environmental perspective. these resources have great potential value. China is a large agricultural nation, have very rich resources of organic solid wastes, but present big quantity and low-utilization, therefore China is face more severe situation than other countries in treating the organic wastes.China is developping "ecological agriculture" and "a low carbon economy", and Walk on the path of sustainable development. How to scientific, economic and effective dispose the organic solid wastes has been the main parts which restricting it’s development.This article was finished under the help of " the integration and demonstration of the cycling agricultural technology which with Straw energy-oriented into the core" (project Numbers: 2130106-38), which is one project of the China agricultural science and technology plan.this article is based on the following factors , sufficient research the current facts ,such as low- utilization and difficult- utilization of the organic solid wastes from the straw, low comprehensive economic benefits of the methane project . and combine the Biogas anaerobic fermentation technology and Organic fertilizer aerobic heap retting technology basised on the present methane project and fertilizer engineering technology, also include the factory craft, equipments. So as to realize the large-scale and high value-added utilization Of the straw wastes and achieve the purpose of improve profitability of the straw feces biogas project.This thesis mainly include the following content:(1)Research on the factory craft which made Straw feces biogas into fertilizer and biogas.The main part is combined the primary aerobic heap retting and the secondary retting anaerobic fermentation, through the small experiment device , complete the determination of the optimal craft parameters of the Straw rapid fermentation manufacturing fertilizer(such as the best ratio of fertilizer and gas, best ratio of reduce the N,P,K loss. etc.).and complete the determination of after rapid -ferment products of straw organic products, such as the organic products, and the content of nutrient elements (mainly include N, P, K). Experiments prove that when straw is fermented with feces for producing biogas and fertilizer ,its optimum proportion is 7:3 and the best production cycle is 30d;(2)Research on the factory equipment which made straw, feces into fertilizer and biogas. Considering the production scale, operation practicability, cost and so on factors, and consult the relevant engineering design and national standards, mainly complete the design and matching of the hoisting equipment, water pressure pool, discharging area, mixture stirring feeding area, etc, validated it and optimization parameter through the small simulator. Experiments have shown that straw feces fermentation tank should adopt monolithic construction, bottom openings, skull cap and so on. Its best top obligate space is 1/10-1/12 and its diameter is 1.5 m in size, 2.4 m in height; Plant adopts the polycarbonate sunshine board, which can significantly improve the fermentation temperature. In xinzheng city of Henan province, the average environment temperature in october was 18.6℃higher than untapped system.(3)The prospective benefits analysis on the factory equipment which made straw, feces into fertilizer and biogas, from the perspective of ecological benefits , environmental benefits, economic benefits and social benefits. The result shows that the factory can effectively process 183708t straw and 78732t pig feces every year in the surrounding area to realize the large-scale straw using and the environment protection. What’s more ,it can also provide 340200 cubic meters for 1553.4 households,and 178695.4 t primary organic fertilizer products for 595651.3 acres. its biogas and organic fertilizer economic profit are 340200 yuan, 17869.54 yuan. its year-round emission is 680400kg CO2 .