预处理+UASB+A/O组合工艺处理肝素钠生产废水

Treatment of Heparin Sodium Production Wastewater by Combined Process of Pretreatment,UASB and A/O

为了满足现阶段环保排放标准对全盐量及TN、TP等指标的更高要求,基于肝素钠生产废水有机污染物、氨氮、无机盐浓度高的特点,采用预处理+UASB+A/O组合工艺实施了处理规模为300 m^(3)/d的废水处理工程。预处理单元以壳聚糖为絮凝剂回收蛋白质,投加MgCl_(2)与废水中的氨氮、磷酸盐反应生成鸟粪石沉淀用作肥料,通过机械蒸汽再压缩(MVR)实现无机盐结晶分离,减轻了氨氮、无机盐对后续生化系统的抑制作用。UASB配有回流系统,对COD去除率可达75%。分段进水三级A/O工艺在外回流比为50%且不需要内回流的情况下,对TN去除率为75%。经该组合工艺处理后,对COD、NH_(3)-N、TN、TP、全盐量等指标的去除率分别为99.7%、99.2%、98.8%、99.8%、99.2%,同时实现了蛋白质、氮、磷、沼气等的资源化利用。

In order to meet the higher requirements of current environmental discharge standards for total salt content,TN,TP and other indicators,based on the characteristics of high organic pollutant concentration,high ammonia nitrogen concentration and high inorganic salt concentration in heparin sodium production wastewater,the combined process of pretreatment,UASB and A/O is implemented in a wastewater treatment project with treatment capacity of 300 m^(3)/d.In the pretreatment unit,chitosan is used as flocculant to recover protein,MgCl_(2)is added to react with ammonia nitrogen and phosphate in the wastewater to generate struvite precipitation for fertilizer,inorganic salts are crystallized and separated by mechanical vapor recompression(MVR),reducing the inhibitory effect of ammonia nitrogen and inorganic salts on the subsequent biochemical system.UASB is equipped with reflux system,and the COD removal rate can reach 75%.Under the condition that R is 50% and no internal reflux is required,the TN removal rate of segmented influent three-stage A/O process is 75%.The removal rates of COD,NH_(3)-N,TN,TP and total salt of the effluent treated by the combined process are 99.7%,99.2%,98.8%,99.8% and 99.2%respectively.At the same time,the resource utilization of protein,nitrogen,phosphorus fertilizer and biogas is realized.