黄孢原毛平革菌在城市剩余污泥中的培养条件优化研究

城市剩余污泥中含有一定的营养物质,可作为微生物的培养基。以黄孢原毛平革菌为对象,从剩余污泥和马铃薯葡萄糖液体培养基(PDL)配比、接种量、摇床转速、培养温度和时间等方面进行试验研究。结果表明:在100mL培养体系中含30g剩余污泥、40mLPDL或3g葡萄糖(pH=6.5),接种1 mL含107mL-1黄孢原毛平革菌的孢子悬液,温度为28℃,转速为150 r/min,培养84 h,得到黄孢原毛平革菌生物量可达3.3 g,剩余活性污泥的生物学转化率为30%~50%。城市剩余污泥可以作为黄孢原毛平革菌生长的培养基,从而实现污泥的无害化和资源化的最终目标。

Culture condition of Phanerochaete chrysosporium in excess sludge

The present paper is aimed at searching for the optimal culturing conditions of Phanerochaete Chrysosporium in the excessive sludge sewage treatment by taking WULONGKOU sewage Treatment Plant(WWTP) in Zhengzhou,Henan,as a case study.As a matter of fact,the core technology used to treat the average amount of 200 000 t of the domestic sewage each day is the activated sludge process(ASP).And,in turn,the excess activated sludge is the chief by-product of the ASP,which is characteristic of high water content(85%-75%) and high organic ingredient(60%-70%).The said two ingredients can be used to culture P.chrysosporium,a kind of white rot fungi,easily cultured under the limited carbon and nitrogen source.So far we know,it is possible for 10 g of excessive sludge to get sterilized to inoculate 1ml of spore suspension of P.chrysosporium(107 mL-1) when blended with 20-100 mL potato detrose liquid(PDL) in 100 mL volume.The optimal adding dosage of PDL proves to be 40 mL for getting maximum biomass on the condition that the sludge is let to dry a whole day and night at 65 ℃ after 6 days oscillating condition at 28 ℃ 150 r/min.We have also tested and confirmed the other influential factors,such as quantity of the excess sludge,inoculation content(v/v),shaking revolution,cultural temperature combined with the same procedure.The optimized culture system should include a 100 mL liquid(pH=6.5),containing 30 g excess sludge and 40 mL PDL in 250 mL flask, inoculation of 1mL spore suspension(107 mL-1) of P.chrysosporium and cultured 84 h at 28 ℃ 150 r/min.The maximum biomass of P.chrysosporium which had been harvested should be 3.3 g,though still not yet enough analysis has been done about the liquid volume in 250 mL flask.In addition,we have also studied the substitution carbon nutrient source in the process of the glucose,lactose,xylose,fructose,maltose and sucrose.Furthermore,as our investigation shows,the adding dosage of glucose had been after glucose been selected as optimum carbon resource and the optimal addition dosage was 3 g.The extra sludge can be used as culture medium acting as carbon and/or nitrogen source validated by the above said tests though biological conversion rate will be likely to 70%-90% aim(only 30%-50%).Further studies are in progress to realize the harmless and resources of excess sludge.