The project aimed to investigate the descriptive information of the animal husbandry in Yunlin County, including the distribution of animal husbandry, the percentage of pollution contributed, and the relative position between affected critical monitoring stations nearby. The objects of the project are the animal husbandry business with registered certificates for breeding livestock or poultry. The range of the survey covered Beigang, Xinhuwei, Zhuoshui River basin, and Dayilun, Bajiaoting, Shicuoliao, Youcailiao, Magongcuo, as well as Niutiaowan Drain. The crucial water quality monitoring stations of Tokooda, Hifon, and Fon Bridge were also included.
Based on the distribution of animal husbandry and pollution load condition, the project proposed a list with 331 livestock farms suggested further consultation for the policy of “biogas and fermented residue as farmland fertilizer”. Listed livestock farms were visited to check whether the facilities are compliant for regulations, such as the current conditions of wastewater treatment facilities in farms, days of anaerobic fermentation, conditions of biogas collection and utilization, and farmlands for biogas and fermented residue irrigation. The application procedures for biogas and fermented residue as fertilizer, as well as related water pollution regulation were also introduced to the farm owners.
In order to raise farm owners’ interest in application of “biogas and fermented residue as farmland fertilizer”, 2,000 fine printed guidance brochures were handed out during on-site counseling and promotional meetings. 1 short films about the biogas and fermented residue irrigation were made to promote the effectiveness. 20 meetings were held by the date of November 30, 868 participants joining, and 85 willingness questionnaires collected. There are a total of 10 animal husbandry industries that are willing to apply, of which 3 have assisted in making applications and approved. In addition, the usage of the biogas fermentation residue farmland fertilizers was observed on September 25. The number of participants on the day reached 36. During the observation meeting, the livestock farmers learned how to transport by tanker transports, and how to build the biogas power generation equipment. Meanwhile, it can communicate with the visitors through the field to reduce the doubts of the livestock farmers.
As the performance tracking for the livestock farms which were approved to implement the “biogas and fermented residue as farmland fertilizer” project, 70 farms have underwent groundwater and soil examination. The results along with the upcoming examination during high-water period will compare to the background level before implementation in 2016-2017 to understand the potential impacts of the irrigation to groundwater and soil nearby. The project will also assist other 4 qualified farmlands for the administration of application.
In regards to assisting the application of “biogas and fermented residue as farmland fertilizer” for potential farmers. 77 farmlands have conducted examination on biogas and fermented residue, 78 farmlands have already been examined in soil and groundwater level, and 234 Farmlands expected to be irrigated have underwent precision analysis by the date of November 30. Compilations and submissions of 78 applications were completed. There are 52 applications have been approved, and 10 reports keep modifying according to the opinions from committee members, and the remaining 15 meetings are expected to be held in December. From a total of 133 animal husbandry operators located at the key stations, 31 livestock farms have been approved, the area of farmland for irrigation is 91.09 hectares, and the amount of irrigation is 31,617.89 (metric tons/year). The total reduction of BOD is approximately 552.76 (kg/day), the reduction of SS is 735.81 (kg/day), and the reduction of NH3-N is 33.35 (kg/day). As for the second aspect economic benefit, it can save about 4,161,358 water pollution fees in one year. From 2016 to 2019, the total amount of BOD reduction in irrigation is equivalent to 27.2 times of the average BOD reduction in the Douliu Water Recycling Center in the past five years. The third aspect in the use of chemical fertilizers can save 34,250 bags of No. 5 Fertilizer, equivalent to 11,302,500 NT dollars expenses.
The most common problems in the implementation of the project include insufficient anaerobic days, no biogas bags and no irrigation land can be used for match. Besides, it is unclear how to carry out the irrigation of biogas fermentation residue, and there is no irrigation vehicle to use, or not able to match the carrying time of the livestock farm. The problem solving-method can be determined by the competent agricultural authority according to individual plans, and the number of days for anaerobic fermentation is also approved. It can be applied as a biogas reheating lamp for boilers, hot water for boilers, and so on, and can be applied to the red mud biogas bag subsidy of the Council of Agriculture, Executive Yuan. If there is no farmland, the farmers can be the main target of the promotional meeting. By contacting the fruit and vegetable production cooperatives, production and marketing teams or farmers' associations in each township, it can help farmers and make them understand the current government policies, and thus willing to engage with animal husbandry. By film-making, brochure-making, and cooperating with experienced farmers, the county government may help farmers know how to apply irrigation. If there is no irrigation vehicle for carrying, or it is unable to match the carrying time of the livestock farm, the person in charge of the animal farm, the industrial group and the township office can help apply for the biogas fermentation residue purchased from Yunlin County Government. The subsidy for the vehicles and biogas fermentation residue farm storage tanks may increase convenience for implementation and enhance willingness.