What is COD online water quality detector?
Release time:2025.11.27
What is a COD online water quality detector?
The following is a detailed introduction to the COD online water quality detector, combined with its principles, functions, application scenarios and technical features:
I. Definition and function of COD online water quality detector
COD (chemical oxygen demand) is the core indicator for measuring the degree of organic pollution in water bodies. It refers to the amount of oxygen consumed when reducing substances (mainly organic matter) in water are oxidized by strong oxidants under certain conditions (unit: mg/L).
The COD online water quality detector can monitor the COD value in water bodies in real time and continuously, and quickly reflect water quality changes through automated analysis. It is suitable for pollution control and early warning in industrial wastewater, domestic sewage, surface water and other scenarios.
II. Core working principle
The mainstream COD online detector adopts potassium dichromate oxidation-spectrophotometry:
1. Sampling and pretreatment: extract water samples through self-priming pumps or peristaltic pumps, and filter to remove impurities.
2. Oxidation reaction: Under high temperature (165℃) and strong acidic conditions, organic matter in the water sample reacts with potassium dichromate to reduce Cr⁶⁺ to Cr³⁺.
3. Photometric detection: Use a spectrophotometer to measure the color change of the solution after the reaction (the concentration of Cr³⁺ is proportional to the COD value) and calculate the COD concentration.
4. Anti-interference design: Add mercuric sulfate to complex chloride ions to eliminate the interference of high-chlorine wastewater.
III. Functions and technical parameters
1. Core functions
- Real-time monitoring: Supports 24-hour continuous detection, and the measurement interval can be set (such as 10 minutes to several hours).
- Automated operation: Automatically complete sampling, digestion, colorimetry, cleaning and data storage.
- Alarm and control: When the standard is exceeded, the sound and light alarm is triggered, and the equipment (such as valves, pumps) can be linked to adjust the processing flow.
- Data management: Built-in storage (≥5 years of historical data), support RS485 remote transmission, compatible with SCADA system.
2. Key technical indicators (UVsense-COD)
Parameter Typical Range Accuracy Response time
COD measurement range 10-20000 mg/L (optional in steps) Within ±2.5% 20-30 minutes
IV. Application scenarios
- 1. Industrial wastewater treatment: chemical, pharmaceutical, papermaking and other high-pollution industries, real-time monitoring of whether the COD at the discharge port meets the standard.
- 2. Sewage treatment plant: optimize the treatment process (such as adjusting the aeration time) to ensure that the effluent meets the discharge standard.
- 3. Environmental monitoring: long-term monitoring of surface water such as rivers and lakes to promptly detect pollution events (such as blue algae outbreaks).
- 4. Emergency response: rapid assessment of water quality impact in sudden pollution accidents (such as oil spills).
V. Advantages
- · Timeliness: 10s to get the result, more timely than laboratory testing (several hours).
- · Economical: reduce the cost of manual sampling, no chemical reagents required.
- · Stability: resistant to harsh environments (such as high temperature and high salt), suitable for long-term unattended operation. The sensor has its own cleaning function
VI. selection suggestions
- 1. Measurement range: select low range (such as 0-100 mg/L) or high range (such as 0-20000 mg/L) according to needs.
- 2. Intelligent function: give priority to models that support remote control and automatic calibration.
- 3. Compliance: confirm that the instrument complies with national or industry standards (such as HJ/T 377-2018).
VII. Typical cases
- ·Case 1: A chemical plant monitors the pretreatment tank in real time through an online COD detector. When the COD exceeds 500 mg/L, the amount of flocculant is automatically increased to ensure the stability of subsequent biochemical treatment.
- ·Case 2: The environmental protection department deployed an online COD meter on the main stream of the Yangtze River. In 2024, it successfully warned of an abnormal increase in COD in a tributary to avoid the spread of pollution.
Real-time monitoring of COD water quality online detectors can significantly improve the efficiency of water quality management and provide data support for pollution prevention and control.
Latest news
Catalogue
Application
About Us
Contact Us
Bebur Beijing China(Marketing &Sales)
sales@bebur-tech.com
Bebur Sichuan China
( Factory&After sales Service)
technology@bebur-tech.com
Bebur UK
info@bebur-tech.com
Tel：
E-mail：
Whatsapp：
skype：
在线客服添加返回顶部
右侧在线客服样式 1,2,3 1
图片alt标题设置： Bebur
表单验证提示文本： Content cannot be empty!
循环体没有内容时： Sorry,no matching items were found.
CSS / JS 文件放置地