Development And Application Of Biosurfactant As A New Type Compost Amendment

With the development of economy and increasing of municipal domestic waste, much research was done with lots of achievements at home and abroad. However, traditional technology was mostly applied in the field of solid waste composting-treatment. This brought series of problem such as low-efficiency treatment, unstable product quality. As far as biological technique, the lack of microorganism with good capability and fortifier in compost field was one big problem. So the attempt to apply biosurfactant in compost for accelerating the degradation of organic matter was beneficial.Biosurfactants as environment acceptable compounds can optimize the distribution of aqueous phase and gaseous phase, facilitate the forming of liquid film on granule that was the location of biogradation, strength the mass transfer of organic matters, and change the way of degradation through biological effect. All these actions were helpful to enhance degradation-efficiency.Based on above theories, our research was focus on the following aspects and received several conclusions.(l)For rhamnolipid biosurfactant production. Pseudomonas aeruginosa was purchased from China Center for Type Culture Collection. The method was shaking fermentation of typical culture under constant temperature. The three main steps for the production included activation of the strain, seed enrichment of the bacteria and biosurfactant excreting in basal culture. The optimal conditions of the culture medium for the rhamnolipid was obtained. Extraction was adopted in the experiment The product was brownish viscous solid. The result validated the existence of glycolipids in the product. Finally HPLC-MS was adopted for the structure identification of the biosurfactant product and proved the sample was the mixture of monorhamnolipid and dirhamnolipid.(2) For the deep reseach on composting technology, a new type compost device was designed. This aerobic-composting equipment was designed according to the characteristics of domestic waste and using mass balance and thermodynamics principle. Moreover a study was done on how to determine the volume of the storehouse and aided equipment. It was concluded that when the diameter of composting system was less than 2.25m heat preservation should be carried out.