普鲁兰和海藻酸钠包埋微生物用于污水处理的研究

Wastewater Treatment Using Microorganisms Entrapped in Sodium Alginate and Pullulan Immobilization Matrix

摘要:

本研究利用混合固定化微生物技术，结合海藻酸钠（SA）和普鲁兰多糖（Pu）两种生物多糖固定化微生物用于污水处理。本实验发现当普鲁兰多糖添加量为1%，海藻酸钠添加量为7%时固定化颗粒的机械强度、弹性和扩散速率最佳。本研究利用三种能够产淀粉酶、蛋白酶和纤维素酶的微生物作为基础菌种，分别对三种微生物进行固定化；本研究对三种微生物在固定化过程中的种子液添加量进行了优化，发现制备固定化颗粒的种子液添加量为200 mL时，污水处理效果较好，污水经过7天的处理TN去除率达65.94%，水体中COD的去除率达77.88%。三种固定化颗粒经过复配后用于污水处理，当固定化颗粒11008、11009和10004添加量分别为0.75%、0.50%和0.50%时，连续处理污水7 d后水体TN去除率高达90.55%，水质COD的去除率高达91.45%。

Abstract:

The aim of this study was to develop immobilized systems for wastewater treatment by immobilizing microorganisms in mixed matrices. Two bioactive polysaccharides, sodium alginate (SA) and pullulan (Pu), were used to immobilize microorganisms for wastewater treatment. The optimum mechanical strength, elasticity, and diffusion rate of the immobilized beads were obtained upon addition of 1% Pu polysaccharides and 7% SA. Three base strains of bacteria (which produce amylase, protease, and cellulose) were immobilized in SA or Pu matrices for wastewater treatment. The seeding quantity for microbial immobilization was optimized. A seeding quantity of 200 mL during the preparation of immobilized beads helped achieve efficient wastewater treatment. The total nitrogen (TN) and chemical oxygen demand (COD) removal rates observed during the end of a seven-day treatment period were 65.94% and 77.88%, respectively. Three types of immobilized beads were compounded for wastewater treatment. The immobilized beads 11008, 11009, and 10004 were added at concentrations of 0.75%, 0.50%, and 0.50% of the total volume of wastewater, respectively, and wastewater was treated for seven days continuously; the TN and COD removal rates under these conditions were observed to be up to 90.55% and 91.45%, respectively.