| 英文摘要 |
This project seeks to first understand the current status of domestic pig farms, then proposes the best approach to promote the optimal animal feces reuse technology, through survey of types of pig barns and collection methods of feces, as well as studying the current regulations on animal farms’ pollution source reduction. Moreover, this project also collected information on operating conditions for pig toilet demonstration projects, analyzed the differences in relevant indicators before and after the installation of pig toilets and assessed the effectiveness of pig toilets in promoting cleaner pig farm practices. The completed work items and results achieved through implementation of this project are summarized as follows:
1. Analyzed the advantages and disadvantages of various domestic pig barn designs and completed the survey of barn types and feces collection methods for 601 pig farms (through field visits (214), questionnaires (10), and data collection (377)). The survey results show that the majority of pig barns are the conventional planar cleanup type (89.5%); and pig feces and urine are collected mostly through flushing with water (94.7%). This information is used to determine the pollution hot spots for the pig farming industry. .
2. Offered consultation services to 50 pig farms. In addition to providing recommendations on proper collection of pig feces and urine, this project also helped detect deficiencies in operations of three-stage wastewater treatment facilities, such as anaerobic pond mostly without or with damaged red mud bags, insufficient aeration in aeration tank, and no sludge return facility in the final settling tank. Specific improvement recommendations are also provided to correct for these deficiencies.
3. Conducted on-site visits of 50 farms’ demonstration pig toilets, and compiled data on the differences in farming operating conditions before and after installation of the toilets, including water consumption, manpower loading, smell, mature rate and influent/effluent water quality, and used these data for the analysis of demonstration sites’ environmental and economic benefits. The results showed that the average utilization rate of pig toilets is 70%, and an average of 40% water saving, electricity saving and barn washing time can be achieved. Moreover, the farms’ pig mature rate can be increased about 2.6% in average, with pollutant reduction averaging 40% (SS = 43.5%, COD = 46.4%, ammonia = 27.2%).
4. Collected information on domestic and foreign technologies for reuse of pig urine and feces (including reuse of biogas from anaerobic digestion, composting, as fertilizer for mushroom cultivation, and as feed for breeding of maggots, etc.), and successful case studies; as well as analyzing the development status, economic benefits, environmental benefits and competitiveness (SWOT analysis) of these technologies. The results from the analysis showed that reuse of biogas from anaerobic digestion is the best option for domestic application, followed by composting. These conclusions are subsequently used in developing the draft promotion strategies for reuse of domestic pig feces and urine from pig farms, as well as in proposing different types and scale of pig barns, and strategies and programs for promoting composting technology.
5. Collected domestic and foreign laws and regulations regarding animal farming, and analyzed relevant domestic regulations governing cleaner pig farming practices. Results from this analysis are used to propose revisions for relevant regulations, including revisions of measure on collecting water pollution fee, and addition of a dedicated chapter on resource recycling; as well as creating an incentive program for pig farmers’ adoption of reuse practice for pig feces and urine and practicing pollution source reduction measures.
6. Organized seven cleaner pig farming consultation seminars, and invited all interested parties to study and discuss the issues regarding revisions of regulations governing resource reuse of pig feces and urine, promotion of pollution source reduction as well as master plan for optimal promotion program for cleaner pig farming practice.
Finally, results from the above tasks are compiled and used in developing master plan for optimal promotion program for cleaner pig farming practice, promotion plan for pig feces and urine recycling and reuse, and manual for operations of animal barns, in order to implement the policy of cleaner pig farming.
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