| There are three aspects of clean technologies in cleaner production including in this paper. (1) The scenario analysis and LCA methodology were combined to conduct a systematic environmental evaluation on three typical pork production scenarios in Sichuan province. The arithmetic about LCA applied to estimate datum of environmental impact categories in current pork production was put forward and all kinds of profiles of environmental friendly aspects and disadvantage and resource efficiency were also discovered. (2) A practical technique called flue heating static windrow of composting (FHSC) was designed, then its working condition and the effect of composting were examined. Another experiment about diversity of microorganism and succession of microorganism community in the composting process was determined by PCR-SSCP and the relationship between the composting indictors and microorganism community was analyzed. (3) The transfer flow of nutrients and energy in the system of rearing housefly larvae with pig manure was explored.In the first project, the main research conclusion was summarized as follows:(1) When the concept of life cycle was introduced, the pork production process was stretched to the processes of the feed production, agricultural materials extracting as well as the recycling process of the pig waste. This kind of environmental analysis could help us profoundly understand the environment issues underlying the system which is limited in pig breeding farm. (2) The concept of "Arable Land Resources Consumption Equivalent Unit (ALRU)" was brought forward and the mathematics model was founded. It could be favorable to compute the agricultural materials consumption under different production background which was based on existing statistics datum and it was also helpful to develop related database in the future. (3) The result showed that the priority order of environmental impact potential of pork production in Sichuan was Land Use, Eutrophication Potential, Acidification Potential, Water Use, Climate Warming and Unrenewable Resources Depletion. (4) The climate warming potential was maximum in scenario A (focusing on farmer family),but Land use and unrenewable resources depletion, eutrophication potential and acidification potential were maximum in scenario B (focusing on 100-head size farm), otherwise water use was maximum in scenario C (intensive farm). (5) The analysis of environment impact contribution at different stage revealed that the water use, land occupation and unrenewable energy consumption was maximum at feed production stage, but climate warming potential, acidification and eutrophication potential were maximum at waste disposal stage. However, resources depletion was not only at the stage of feed production, but also due to the lower efficiency of feed transfer in pig breeding. (6) The measures of improving environment were given as follows:First of all, the production system should be integrated, manure be returned to field as much as possible, feed production technique improved, and feed transportation energy should be saved. The second, the pig breeding, the feed processing, animal environment and waste management need to be improved to minimize the nutrients emission. The third, the organic fertilizer and methane produced from manure treatment and storage facilities should be utilized.The conclusion of study on pig waste treatment system of FHSC was as follows:(1) the temperature inside the FHSC piles, which reached at high temperature phase within 3 hours, increased quicker than that of the conventional composting pile for 40 hours. (2)The process of nitrification was accelerated through adding microorganism agent, so the time of reaching at a stable stage was advanced for 18 days in treat group piles compared to the control group. (3) The runoff was stored in the space at the bottom of piles and then recycled in the system so that the pollution of sewage was avoided and water was also saved. (4) The compost could be dried at the end stage and the pathogens were also killed through the flue heating system. It made the post treatment process be simplified and cost decreased.In the study on the interaction between the main physical or chemical indicators of composting and the succession of microorganism community determined with molecular biological technology of PCR-SSCP, the conclusion was drawn as follows:(1) The change of parameters, such as aeration, temperature and carbon to nitrogen ratio et al., influenced the bacteria and fungi species significantly. The average numbers of bacteria and fungi in the pile of aeration were higher than those in passive aeration pile (2.436 versus 1.54 to bacteria species and 3.128 versus 2.641 to fungi species). The main reason should be caused by the difference of oxygen supply and heat loss leading to different temperature (average temperature in aeration pile and passive aeration pile was 51.6 celsius degree and 56.3 celsius degree respectively during 1-20d).The change of temperature directly influenced the specie number of bacteria and fungi. The specie number of bacteria decreased acutely when temperature was above 68 celsius degree, but the similar situation occurred in fungi community at temperature above 50 celsius degree. The most flourishing phase was during 4-20d or 48-65 celsius degree for bacteria community but 15-24d or 42.5—50 celsius degree for fungi community.(2) The number of bacteria and fungi species decreased quickly to a very low level after 24d. The main impact factors were lower temperature, carbon to nitrogen ratio and organic content. It should benefit the composting ferment process if some microorganism agent was added into the pile and the parameters were regulated on the 24th day.(3) The variance of fungi species was significantly bigger than that of bacteria species. This result proved that fungi species should be more sensitive to composting conditions than bacteria species. The composting microorganism community was thrifty before 27d. An idea situation of bacteria and fungi species being both active could be realized by regulating temperature, C/N, and OC et al.(4) The concentration of CO2 at vent of pile decreased suddenly on the day 27 or 28, it should be a good indicator to show the first phase of composting is over.(5) The more fungi species OTUs were amplified by PCR-SSCP than bacteria species in this research due to the length of fungi primer being shorter than bacteria primer. It proved that the longer the fragment amplified by PCR is, the lesser the species OTUs will be gotten.The conclusion on pig manure treat with housefly larvae was summarized as following:The results showed that the odor intensity of manure was decreased quickly, and content of gross energy was reduced by 41.58%. The total quantity of manure was reduced by 53.04%, which included 31.14%DM (Dry material), and the part of housefly body deposition accounted for 2.85%. The nutrient EE (ether extract) of manure, which consumed the most by housefly, was accounted for 77.81% of total EE, secondly, KN (kjeldahl nitrogen) was 62.81%. However, CF (crude fiber) or NFE (nitrogen-free extract) were both used less and accounted only for 9.28% and 22.03% respectively. Furthermore, the physical and chemical characteristics of manure were significantly changed in the activity of larvae, which benefited the consequent process of biological decomposition so that the residual manure could be directly used as the original material of composting after the larvae were separated. |
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