磷酸铵镁法回收厌氧消化液中氨磷的模型研究及优化  

Model Study and Optimization of Recovery of Ammonia and Phosphorus from Biogas Slurry by Magnesium Ammonium Phosphate Method

作　　者：陈哲 周亶 梁家伟 蒋东云[1] 刘志男 康厚智 CHEN Zhe;ZHOU Dan;LIANG Jiawei;JIANG Dongyun;LIU Zhinan;KANG Houzhi(Guilin University of Electronic Technology,School of Life and Environmental Sciences,Guilin 541000,China)

机构地区：[1]桂林电子科技大学生命与环境科学学院,广西桂林541000

出　　处：《中国沼气》2023年第6期18-25,共8页China Biogas

基　　金：2018年广西重点研发计划项目:畜禽养殖废弃物厌氧共发酵反应器及其在线监测系统研发与示范(桂科AB18221104)。

摘　　要：基于磷酸铵镁(MAP)法回收厌氧消化液中氮磷的反应构建MAP-MINTEQ模型并优化。利用化学平衡模型Visual MINTEQ 3.1结合实验进行建模,取得拟合度较高的模型参数。首先,研究了碳酸盐对磷酸铵镁反应的影响,对比了两种活度系数方程中活度系数γ的影响因素和校正因子,扩展的德拜-休克尔方程更适用于本模型。其次,研究厌氧消化液中复杂缓冲体系对副产物MgCO_(3)沉淀溶解平衡的影响,利用其k_(sp)校正MAP-MINTEQ模型,优化其拟合结果。基于优化的模型,调整厌氧消化液氮磷回收的MAP实验配比,反应后残留的氨氮浓度最低降至41.2 mg·L^(-1),氮回收率达到98.0%;总磷最低降至5.5 mg·L^(-1),磷回收率达到99.2%,实现了氮磷的高效回收。MAP-MINTEQ model was constructed and optimized based on the recovery of nitrogen and phosphorus from biogas slurry by MAP method.Chemical equilibrium model Visual MINTEQ 3.1 was used for modeling combined with experiments,and model parameters with high fitting degrees were obtained.Firstly,the influence of carbonate on the reaction of magnesium ammonium phosphate was studied,and the influencing factors and correction factors of activity coefficientγin the two activity coefficient equations were compared.The extended Debye-Hückel equation were more suitable for MAP-MINTEQ model.Secondly,the influence of the complex buffer system in the biogas slurry on the precipitation and dissolution equilibrium of the by-product MgCO_(3)was studied,and the MAP-MINTEQ model applied calibrated k sp to optimize the fitting results.Based on the optimized model,the experimental ratio of MAP reaction was adjusted to achieve improved nitrogen and phosphorus recovery.According to the calibrated model,the concentration of residual ammonia nitrogen was reduced to 41.2 mg·L^(-1),and the nitrogen recovery reached 98.0%.The lowest total phosphorus is 5.5 mg·L-1,and the phosphorus recovery rate is 99.2%.Thus the efficient synchronous recovery of nitrogen and phosphorus was fulfilled.

关 键 词：磷酸铵镁 氮磷同步回收 厌氧消化液 MINTEQ模型 碳酸盐 

分 类 号：S216.4[农业科学—农业机械化工程] X703[农业科学—农业工程]