Production of granular fertilizer from pig wastes by mixing with calcium oxide, 1: Production method and quality of the product
1997
Miyazaki, N. (Tochigi-ken. Agricultural Experiment Station, Utsunomiya (Japan)) | Omura, H.
Pig wastes could be formed into granules by rotating them with calcium oxide after adjusting the water content to 40-49%. By drying these granules, we could get granular fertilizer without bad smell. The amount of calcium oxide needed to be added varied according to the water content of pig wastes. When the water content of pig wastes was 75%, the optimum amount of calcium oxide was 35 kg per 100 kg of wastes. 85 kg of granular fertilizer was produced from 100 kg of pig wastes with water content of 75%. It takes one hour for the reaction of pig wastes with calcium oxide, three to four hours for granulation, two to five days for drying by solar heat in a greenhouse. If we use a dryer, all process takes only one day. The content of nitrogen, phosphoric acid and potassium was about 1, 2 and 1% respectively. Alkali content was about 50%. This means that it is classified into calcium treated fertilizer under Fertilizer Control Law. Although the nutrient content of this granular fertilizer varies, we can estimate it by the amount of calcium oxide added. The granular fertilizer could be kept for long time at the normal temperature without moisture absorption and quality changes. It could be applied by machine effectively. A large quantity of ammonia gas generated by the reaction of pig wastes with calcium oxide could be caught by acid solution using a dust collector. This method is more economical than the usual composting method
Показать больше [+] Меньше [-]