Process Studies On Co-composting Treatment For Pencillin Fermentation Dregs And Municipal Sewage Sludge

Antibiotics fermentation dregs are the solid waste produced in the manufacturingprocess of Ferment Antibiotics. With high protein content, they are supposed to be akind of potential resources. But they also have the environment risk due to the antibioticresidue inside. In the past, fermentation dregs were made as animal protein feed,however, it was prohibited by the country. The efficient treatment of fermentation dregsis now becoming a restricting factor that impact the development of pharmaceuticalindustries. The purpose of this study was to evaluate the feasibility of using aerobiccomposting to treat penicillin fermentation dregs. The dregs were composted togetherwith municipal sludge, saw dust and rice straw. The physicochemical parameters andthe degradation of penicillin during the process were investigated during process. Themanurial effect and environmental risks were also appraised for the compost.The mixed materials were composted in five glass containers each with the volumeof6L, located in the water baths, two tin trunks, each with the volume of0.4m3, werealso applied as control. The experiment designs are divided into4parts, including theexperiment to detect the hydrolysis of penicillin, the study of the municipal sewagesludge aerobic composting process with the addition of penicillin, the experiment ofco-composting of penicillin fermentation dregs and municipal sewage sludge and thestudy of the nitrogen element during the composting process.The hydrolysis rate of penicillin differed a lot in water under20℃,30℃,40℃,55℃. Under20℃, the loss of penicillin was62%after5days while no penicillin couldbe detected after12hours under55℃. Penicillin with concentrations ranging from30mg/kgTS to150mg/kgTS was added to the composting materials consisted of sludgeand sawdust, no obvious influence was investigated. By the end of the experiment, nopenicillin residue could be detected all of the systems. During the co-compostingprocess of penicillin fermentation dregs and municipal sewage sludge, the best ratio ofdregs:slugde was proved to be between2:1~1:1. The loss of penicillin was over98.9%after the whole treatment in the control systems, in which the maximum temperaturecould achieved as high as64℃. The loss of TN was30%during the composting processwhich meant that the nitrogen element was well maintained during the compostingprocess. The aminoacid-N in the final compost was4.83g/kg which took20.37%of TN,it just declined26%after the whole process, showed that the nitrogen was beneficial forplant to use. The final content of aminosugar-N was241%compared with the initialcontent representing an increase in the number of microorganisms. Penicilloic acid andpenillic acid were detected by LC-MS in the composting product sample which means penicillin was degradated during the composting process. The organic content was highin the final composting product and the N，P，K contents were much higher than theNY525-2011guideline values. The contents of all kinds of heavy metals were quite lowand thus the final composting product was supposed to be a kind of safe organicfertilizer.On the basis of the results obtained in this study, the aerobic composting processwas an efficient way to treat penicillin fermentation dregs, the pencillin residue could beefficiently removed, the nutrient components could be maintained.