The vast majority of rural sewage in my country is directly discharged into water bodies without treatment. Rural domestic sewage accounts for a large proportion of the sources of lake pollution in my country. With the increasing level of urbanization, rural urbanization and urban-rural integration in my country, and the improvement of farmers' living standards, the discharge of domestic sewage in towns and villages will continue to grow rapidly. This will undoubtedly bring more pressure on water source protection. In order to protect urban water sources and gradually improve the quality of the water environment, it is necessary to increase sewage treatment. In order to effectively promote the construction of a new socialist countryside, improve the rural environment in an all-round way, and effectively solve the outstanding problems of the current rural garbage garbage, rural sewage sewage disposal, and lagging governance, accelerate the construction of a new socialist countryside and further improve the rural area Production and living conditions of the masses. The quality of the rural ecological environment must be continuously improved. Therefore, the treatment of small domestic sewage in towns and villages is particularly important.

Rural sewage has the following characteristics:

(1) The sources of pollution are relatively dispersed, the amount of water is small, the concentration of organic matter is high, and the coefficient of daily change is high.

(2) Most rural areas are relatively backward in economy and cannot afford high-input processing facilities, while land resources are relatively abundant.

(3) Lack of corresponding professional management personnel.

Existing technologies mainly use biological methods for domestic sewage treatment: A2O, oxidation ditch and other activated sludge methods commonly used in urban sewage treatment plants. The characteristics of these methods are: the sewage pipe network is required to collect the sewage, the operation of the structure is complicated, the construction and operation cost are high, and the management of professionals is required. Therefore, these methods are difficult to apply to the treatment of rural scattered domestic sewage.

Project Overview

The sewage treatment project of XX Village, XX City, Shanxi Province is a daily sewage treatment capacity of 150T. It passes through various treatment steps such as grille pool (separating floating matter in sewage), regulating tank, anaerobic tank, pre-out-of-stock tank, anoxic tank, aerobic tank The clean water after treatment and separation will be discharged to the constructed wetland, and then ultraviolet disinfection will eventually reach the discharge standard and be discharged to the river.

Project implementation plan

• One mechanical grill is used to control the separation of floating matter and sewage in sewage.
• Sewage flows into the regulating tank through pipeline self-flow, and is sent to the anaerobic tank through the lift pump, and the flow data is monitored.
• It flows to the pre-out-of-stock pool, anoxic pool, and aerobic pool in a self-flowing way.
• The reflux pump in the aerobic tank will transport the sewage to the pre-out-of-stock tank, and the supernatant will flow to the sedimentation tank and sludge tank.
• The supernatant in the sludge tank flows to the clear water tank and the first and second artificial wetlands, and the sludge is discharged through the sludge pump.
• The supernatant is further processed in the constructed wetland and discharged to the river after reaching the discharge standard through ultraviolet disinfection equipment.
• All devices must implement local and remote (touch screen and cloud) control functions.

 

Implementation Plan

 

Fully consider the design requirements and implementation characteristics of the project. In the overall implementation plan, PLC (NA2000) is used for on-site acquisition and control, which realizes the acquisition and display of the status of sensors and equipment, and controls the start-stop switching of on-site equipment according to process requirements. Through the wireless gateway 4G, the video signal, device status and sensors are transmitted to the information management center, which will lay the foundation for later centralized management.

 

The structure diagram of the automatic control system is as follows: