Odorless composting of the organic waste which served as disposal of waste edible fat and oil

在含有废弃食用油脂的有机物料的高速堆肥过程中，当它们被大力降解时，氨气的排放量大大减少。对堆肥过程中氮素的物质平衡进行了详细的研究，发现氨气排放量的减少不是由于脂肪和油脂的降解中间产物--脂肪酸对氨气的中和作用，而是由于微生物吸收氮气计数其微生物细胞所致。此外，在含有三丁酸甘油酯的LBTR琼脂上计数脂肪和油脂降解菌的细胞密度，这些微生物在堆肥中期后有所增加，这与开始明显减少氨气排放的堆肥时间相对应。在LBTR琼脂平板上分离到两株对三丁酸甘油酯具有高效降解活性的嗜热菌LT1和LT4，并对其进行了鉴定。此外，通过对DOM-1菌株的微生物群落分析，发现DOM-1菌株本身不具有降解脂肪和油脂的能力，但通过与菌株LT1和LT4的协同作用而促进了对脂肪和油脂的降解。将含有高细胞密度脂肪和油脂降解菌的堆肥产物作为下一步堆肥的播种材料，将其与堆肥原料混合，证实播种对减少氨气排放和加速脂肪降解是有效的，而且这些效果在堆肥开始后立即出现。此外，还证实了氨气的减排效果并不局限于使用食用油和油脂的情况，矿物油的代表十六烷也是有效的。

During the high-rate composting of organic materials containing waste edible fat and oil, the emission of ammonia gas was drastically reduced when they were degraded vigorously. The material balance of nitrogen was examined in the composting in detail, and it was found out that the reduction of the ammonia gas emission was not due to the neutralization of ammonia gas by the degradation intermediates of fat and oil, i.e. fatty acid, and owed to the uptake of nitrogen by microorganisms for enumeration of their microbial cells. Moreover, the cell density of fat and oil degrading microorganisms were counted on the LBTR agar medium containing tributyrin, and these microorganisms increased after the middle stages of composting, that corresponded well to the composting time when ammonia gas emission began to be reduced clearly. Two thermophilic bacteria, strains LT1 and LT4, with high degradation activity of tributyrin were isolated on the LBTR agar plate and then identified. In addition, the bacterium DOM-1 which itself does not have the ability to degrade fat and oil, but contributed to the degradation of them by cooperating with the bacterial strains LT1 and LT4 was determined by the microbial community analysis with the PCR-DGGE method. The DOM-1 was identified from DNA sequence of the band excreted from the gel.The compost product which contains high cell density of fat and oil degrading microorganisms were used as a seeding material for the next composting by mixing it to the composting raw material, it was confirmed that the seeding was effective for reduction of ammonia gas emission and the acceleration of fat degradation, moreover these effect appeared immediately after the start of composting. In addition, it was ascertained that the effect of the ammonia gas reduction was not limited to the case using edible fat and oil, but, hexadecane, one representative of mineral oils also was effective.