Study On Tracebility Control Technology About Toxic Substances In Urban Sewerage System

Urban sewage is often mixed with industrial wastewater in china, and industrial wastewater usually contains toxic organic compounds, toxic inorganic compounds, heavy metals and other toxic substances. If a wastewater treatment plant without early warning and monitoring, once a certain amount of toxic substances flow into it, the activated sludge system of wastewater treatment plant will be crashed, and the wastewater treatment plant will cause serious economic losses and new environmental pollution. Especially for medium and small factories in the reservoir area, which have relatively low level of management, sewage accidents happen frequently. It is frequently observed that enterprises discharge pollutant without permission or beyond pollution limits to maximize their profits, resulting in the difficulties of wastewater treatment plant operation and maintenance, substantial increase in operating costs, instability of the treatment effect. So, the monitoring and management of sewerage system plays an increasingly prominent position.We choose Chengbei wastewater treatment plant and supporting sewerage system in Yubei District as the research object, combined with GIS software to construct urban sewerage system tracing toxic substances monitoring system, achieving the purpose of sewerage system information management, water quality monitoring, and traceability analysis. The main research contents and conclusions are as follows:â‘ Through the experiment monitoring to water quality of sewage pipes, much data has been collected and the characters of the sewage in pipe networks and Chengbei wastewater plant have been find out. These can be used for establishing and checking the model.â‘¡Setting up a sewerage system one-dimensional water mode for monitoring points on the demonstration area. The one-dimensional hydrodynamic model is based on the Saint-Venant equations. The Preissmann implicit seheme is used to diserete the Saint-Venant equations. The pipe-junction-pipe method is applied to resolve the hydrodynamic model for pipe networks. The one-dimensional water quality model is based on the adcection-diffusion equation, which is discreted by the implicit difference scheme, and solved by"sweeping method".â‘¢At the aspect of working over ArcGIS 9.3.1 which produced by ESRI, using ArcGIS Engine plus the organic integration GIS and model which using C++ language for numerical by the way of module type second development. And use"test method"to determine the enterprise which discharge excessive waste water.â‘£Setting up three monitoring points in sewerage system, and selecting pH and conductivity for on-line monitoring indexes, then building sewage pipe network tracing monitoring system based on GIS. The system could not only has conventional sewage pipe network information management functions, while has the functions of monitoring water quality sewage pipe network. When water quality exceeded the stipulated standards, it can early-warning prompt, and source analysis of the potential enterprises which discharge excessive wastewater.The system of tracing and monitoring toxic substances in urban sewerage system, which has the capable of dynamic monitoring of the sewage pipe network, and could provide decision support safe and reliable operation for urban sewerage system and wastewater treatment plant, and excessive discharge of wastewater potential traceability. It has important practical significance.