一株污泥减量菌喷雾干燥条件的优化

使用摇瓶发酵制备解淀粉芽孢杆菌，喷雾干燥将其制备成菌粉。采用单因子实验首先对影响摇瓶发酵制备解淀粉芽孢杆菌的条件因素进行优化，然后采用单因子实验和正交实验，对影响喷雾干燥产物指标的因素进行优化。优化后的摇瓶发酵条件为：5g/L可溶性淀粉、10g/L氮源（酵母粉与蛋白胨体积比为2：1）、接种量7%、摇瓶装液量40%，摇床200r/min、30℃条件下摇瓶发酵48h，菌液活菌数为8.3×10⁸CFU/mL，优于优化前的3.8×10⁸CFU/mL。优化后的操作条件为：进风温度180℃、热风流量315m³/h、进样速度500mL/h、麦芽糊精质量分数5%。各因素对其喷雾干燥工艺的影响程度为：麦芽糊精浓度 > 进料速度 > 进风温度 > 空气流量。在此条件下，解淀粉芽孢杆菌菌粉活菌数可达1.28×10¹⁰CFU/g。

Spray drying technology of a sludge reduction bacteria

Fermentation broth of amyloliquefaciens was granulated by spray-drying technology to develop new formulation. Single factor test was used to improve the viable cells number of amyloliquefaciens. Single factor test and experiment with four-factor and three-level orthogonal were carried out to optimize spray-drying condition. The optimization of cultural condition were obtained as follow, 5g/L soluble starch, 10g/L yeast powder and tryptone mix (2:1, V/V), shaking speed 200r/min, temperature 30℃, inoculation rate 7%. The optimum conditions were inlet air temperature 180℃, hot air flow 315m³/h, feed flow rate 500mL/h, maltodextrin concentration 5%. The most leading influence factor on the production of viable cells was the maltodextrin concentration, followed by feeding speed, inlet temperature and air flow. The number of viable cells of products reached to 1.28×10¹⁰CFU/g under the optimal conditions. These data helps development of new formulation of amyloliquefaciens.