猪场废水生产微生物絮凝剂发酵特性及动力学特征

以猪场废水作为原材料生产微生物絮凝剂,考察了发酵过程中溶解氧(DO)、COD、氨氮、总磷及pH值的变化规律,利用Logistic和Luedeking-Piret模型对絮凝菌生长和代谢产物生成的动力学过程进行了拟合.结果显示,菌体的生长在0~60h是对数生长期,12~36h菌体快速生长,菌体干重、细胞浓度OD600和菌落数分别由0.09g/L,0.26和1.3×107cfu迅速增加到0.76g/L,0.58和3.5×107cfu,稳定期(66h)菌落数达到5×107cfu.絮凝菌代谢产物的主要絮凝活性成分是蛋白质,与菌体生长呈相关型.猪场废水中磷源含量充足,作为缓冲液,基本维持了絮凝菌发酵过程中pH值的恒定.此外,Logistic和Luedeking-Piret模型的拟合结果能够较好地描述絮凝菌生长和代谢产物生成的动力学过程.

Fermentation and kinetics characteristics of bioflocculant production using swine wastes as raw material

Swine wastewater was used as raw material to produce bioflocculant. Concentration of dissolved oxygen (DO), COD, ammonium, total phosphorus (TP) and solution pH values in the fermentation process were examined. Growth and producing kinetics models of the bacteria were described by Logistic and Luedeking-Piret equations. During the logarithm phase (0~60h), especially in 12~36h, cells grew rapidly. Cell dry weight, cell density OD600, and the number of colonies increased from 0.09g/L, 0.26 to 1.3×107cfu to 0.76g/L, 0.58 and 3.5×107cfu, respectively. The number of colonies reached its maximum value of 5×107cfu at 66h. Protein, the main active ingredient of the metabolite, was produced in parallel with cell growth. Phosphorus in the swine wastewater was essential for adjusting pH values during the flocculation process, and its content was adequate. Furthermore, the cell growth and bioflocculant production simulated very well with both the Logistic and Luedeking-Piret equations.