5 notes to know about wastewater monitoring stations

1. Automatic wastewater monitoring station

Automatic wastewater monitoring station is an automatic system used to monitor and measure wastewater parameters.

Automatic wastewater monitoring stations are installed to monitor the quality and components contained in wastewater from different sources, such as wastewater treatment plants, industrial facilities, pumping stations, or points receiving wastewater from households and other sources.

2. Monitoring station parameters are automatically provided

Automatic wastewater monitoring stations are often equipped with sensors and measuring equipment to measure the amount and content of substances in wastewater such as:

+ pH: Measures the acidity or base level of wastewater.

+ BOD (Absorbed Oxygen Demand): Measures the amount of oxygen needed to decompose organic matter in wastewater, showing the level of organic pollution.

+ COD (Chemically Absorbed Oxygen Demand): Measures the amount of oxygen needed to oxidize organic substances with strong oxidants.

+ Dissolved solids quality (TSS): Measures the amount of dissolved solids in wastewater.

+ Electrical conductivity (EC): Measures the ability of wastewater to conduct electricity, thereby evaluating the ionization of water.

+ Other pollutants such as nitrates, ammonia, E. coli bacteria, heavy metals and other toxic chemicals.

Data collected from automatic wastewater monitoring stations help businesses, environmental management agencies and researchers to better understand the wastewater quality and pollution, thereby providing management measures. Effective treatment and treatment to protect the water environment and ensure community health.

3. Technology and equipment for installing wastewater monitoring stations

Technology in wastewater monitoring stations plays an important role in collecting and processing data to evaluate wastewater quality and help to make effective water environment management decisions. Below are some common technologies used in wastewater monitoring stations:

- Sensors and measuring equipment: Sensors are used to measure wastewater parameters such as pH, dissolved oxygen concentration (DO), chemical concentration (such as BOD, COD), dissolved solids (TSS) concentration, concentration of other pollutants such as nitrates, ammonia, heavy metals, bacteria, etc. These sensors are often attached to automated equipment and continuously collect data.

+ pH sensor: Measures the acidity or base level of wastewater, this is an important parameter for evaluating the acid-base nature of wastewater

+ Dissolved oxygen (DO) concentration sensor: Measures the amount of oxygen in wastewater, which is directly related to pollution levels and the vitality of the water ecosystem

+ Sensor to measure the concentration of chemicals (BOD, COD): Measures the amount of oxygen needed for organic decomposition (BOD) and the amount of organic matter in wastewater (COD);

+ Dissolved solids concentration sensor (TSS): Measures the amount of dissolved solids in wastewater;

+ Sensors measure concentrations of other pollutants such as nitrates, ammonia, heavy metals, E. coli bacteria, etc.

- Automation system: The wastewater monitoring station uses automation systems to monitor and control the measurement and data collection process. This system enables 24/7 monitoring and minimizes manual intervention, while improving data accuracy and reliability.

- Linked network technology: Wastewater monitoring stations are often connected to a linked network to transmit environmental data quickly and effectively. This may include use of the internet, cellular networks, private networks, or other communications protocols.

- Data storage system: Wastewater monitoring stations use data storage systems to organize, manage and store information collected from sensors and equipment. This data can then be used to analyse and take steps to adjust and improve the wastewater management process.

- Data management software: Use of special data management software to effectively process and analyse data from wastewater monitoring stations. This software helps to monitor, display and analyse data related to wastewater quality accurately and effectively.

4. Regulations on installation of automatic wastewater monitoring stations according to Decree 40 

Pursuant to Clause 2, Article 39, Decree 40/2019/ND-CP - Regulations on installation of automatic wastewater monitoring stations, there are provisions as follows:

Installation object

“Subjects must perform automatic and continuous wastewater monitoring (except for the following cases: facilities connected to a centralized wastewater treatment system, aquaculture equipment and facilities with water treatment systems, periodic tank cleaning waste which is separated from the wastewater treatment system, facilities with cooling water do not use chlorine or disinfectant chemicals to kill microorganisms, and facilities with mine drainage water for mineral exploitation, common building material, limestone), including:

a) Industrial parks and facilities located in industrial parks but exempt from connection to the centralized wastewater treatment system

b) Production, business and service establishments of the type of production at risk of causing environmental pollution specified in Appendix IIa Section I of the Appendix issued with this decree and with a discharge scale of 500 m3/day (24 hours) or more calculated according to the design capacity of the wastewater treatment system

c) Hazardous waste treatment facilities, provincial-level centralized solid waste treatment equipment and facilities using imported scrap as production materials that generate industrial wastewater or leachate environment, subject to preparing an environmental impact assessment report

d) Production, business and service establishments other than those specified in Points a, b and c of this clause, with a discharge scale of 1,000 m3/day (24 hours) or more based on capacity design of wastewater treatment system

d) The facility is administratively sanctioned for discharging wastewater in excess of environmental technical regulations and if the violation is repeated

Technical requirements when installing wastewater monitoring stations

+ The automatic wastewater monitoring system must provide accurate and reliable data on wastewater quality. Sensors and measurement equipment must be periodically calibrated and maintained to ensure the measurement accuracy. The wastewater monitoring station must ensure equipment accuracy for flow parameters, temperature, color, pH, TSS, COD, NH4+, total Nitrogen, total Phosphorus, TOC, residual chlorine 

+ The wastewater monitoring system must operate automatically and continuously, helping to minimize an annual intervention and ensuring that the measurement and data collection process takes place continuously. The monitoring equipment should automatically store and export the monitoring results and status information

+ Standard substances must be checked periodically, meeting at least 1 concentration point in the measurement range 

+ The requirements for an automatic sample collection and storage equipment should be met.

How to manage and operate the automatic wastewater monitoring system 

The management and operation of the automatic wastewater monitoring system must comply with the following regulations: 

+ It is necessary to set the measuring range for the system, during the operation, the system must transmit data to the receiving unit and the measuring equipment must be installed within the limits prescribed by national technical regulations on the environment. 

+ The system quality must be managed, maintained and operated continuously, without interruption. It is necessary to keep the records of the system operating unit on parameters, the technical characteristics of the equipment, the use instructions, the procedures, the log books of operation, the maintenance, servicing, inspection and calibration of the equipment.  

+ The monitoring units must verify, calibrate, test and periodically inspect the equipment to ensure a stable operation.

5. Steps to operate an automatic wastewater monitoring station

Operating an automatic wastewater monitoring station is an important process to collect wastewater quality information automatically and continuously. Some basic instructions on how to operate an automated wastewater monitoring station are listed in the following:

- Pre-operation check: Before starting operation, all devices, sensors and systems must be checked. Also, the firmware and data management software must be updated and working properly.

- System startup: The system must be turned on in order to check if the sensors and measuring devices are working properly. It must be checked that the measured data is recorded accurately and in the correct format.

- Wastewater sampling: Automatic wastewater monitoring systems often use automatic pumps to take wastewater samples from different sources and put them into measuring devices. The pump should be operating properly and the sampling must be done according to the configured schedule.

- Measure wastewater quality: Sensors will automatically measure parameters such as pH, dissolved oxygen (DO), BOD, COD, TSS and other pollutants. The sensors must be properly calibrated to ensure the accuracy of the measurement data.

- Data collection: The system will automatically collect data on wastewater quality according to configured time intervals. This data will be stored and organized into a data storage system.

- Monitor performance: The performance of the automatic wastewater monitoring system has to be monitored to ensure that the system operates reliably and without problems. If there are any errors or problems, they should be checked and repaired promptly.

- Maintenance and replacement: Sensors and equipment must be maintained and if needed replaced to ensure the accuracy and reliability of collected data.

- Data processing: Data collected from automatic wastewater monitoring stations need to be stored and processed accurately. The data must be recorded and organized properly.

- Reporting and analysis: The data collected from automatic wastewater monitoring stations must be analysed and reports on water quality and the environment must be established which will help to provide useful information to make decisions concerning the management and the protection of the water environment.

- Ensure safety: The safety during the operation of the automatic wastewater monitoring station must always be guaranteed. Accidents should be avoided by taking the necessary safety measures.

By following those steps and implementing them thorough the operating procedures, an automated wastewater monitoring station can operate effectively and provide important information about the water environment to support management and conservation. Therefore, the water resources can be protected in the best way.

Building an automatic wastewater monitoring station is a service in FEC's environmental monitoring and analysis activities in Bac Giang. The quality monitoring plays an important role in protecting the aquatic environment, monitoring wastewater quality and helping to meet legal requirements related to wastewater management. With professional experience in the field of consulting and designing environmental monitoring stations , FEC Bac Giang Environment will bring the best services to the customers.