典型城镇污水处理厂碳源智能投加控制生产性试验

FULL-SCALE STUDY OF AN INTELLIGENT CARBON DOSING CONTROL SYSTEM IN A TYPICAL URBAN WASTEWATER TREATMENT PLANT

乙酸钠、甲醇等药剂是污水处理厂为保障反硝化脱氮效果所投加的外碳源,然而污水处理厂存在碳源实际投加量与反硝化碳源需求量不匹配的问题。针对污水生物处理过程反硝化碳源的动态需求,研究提出了基于在线实时监测的碳源投加智能控制算法,开发了污水处理碳源智能投加控制系统,以克服人工调控碳源投加存在的过量加药、调控滞后、碳排放量高以及工艺稳定性问题。在污水处理厂进行了4个月的生产性试验,结果表明:控制系统正式运行以来出水水质稳定达标,日均乙酸钠投加量与2020年同期相比降低了21.2%,月均节省乙酸钠药剂费用4.72万元。该项技术可在保障污水处理工艺稳定的前提下实现对碳源投加的精准控制,为污水处理厂自动化运行和减污降碳提供技术和装备支撑。

Sodium acetate and methanol are widely used as an external carbon source to enhance denitrification for nitrogen removal in wastewater treatment plants. However, the carbon dosage hardly matches the carbon requirement for denitrification properly in practice. To satisfy the dynamic requirements of carbon for denitrification in wastewater biological treatment processes, a real-time online surveillance based intelligent carbon dosing control algorithm was proposed and an intelligent carbon dosing control system was therefore developed to solve the problems caused by manual control of carbon dosing, e.g. over-dosing, time delay, extra carbon dioxide emission, and process stability. Full-scale tests were carried out at a wastewater treatment plant for four months, and the results indicated that the effluent achieved the discharging proposal constantly, meanwhile the sodium acetate consumption was reduced by 21.2% and the chemical cost for acetate acid was reduced by RMB 47200 per month. This work showed an approach to control carbon dosing accurately as well as stabilize the process, which provided technical and equipment support for WWTP automation and carbon emission reduction.