Industrial waste gas online monitoring system

System Overview:

Nitrogen oxides include various compounds, such as nitrous oxide (N)₂O）、 Nitric oxide (N0), nitrogen dioxide (NO)₂）Nitrogen trioxide (N₂0₃）Nitrogen tetroxide (N₂0₄）And nitrogen pentoxide (N₂0₅）Wait. Except for nitrogen dioxide, other nitrogen oxides are extremely unstable and turn into nitrogen dioxide and nitric oxide when exposed to light, moisture, or heat. Nitric oxide then turns into nitrogen dioxide. Therefore, the industrial environment is exposed to a mixture of several gases commonly known as nitrate (gas), mainly nitrogen oxide and nitrogen dioxide, with nitrogen dioxide being the main component.nitrogen oxidesWhen combined with water in the air, it will eventually transform intonitric acidandnitrateNitric acid is one of the causes of acid rain, and it can produce other pollutants under certain conditionsphotochemical smogPollution.
In the environmental protection indicators of the national 12th Five Year Plan, it is explicitly required that the total emissions of nitrogen oxides in 2015 be reduced by 10% compared to 2010. Key industries such as electricity will be regulated, and efforts will be made to accelerate the treatment of nitrogen oxides in industries such as steel, cement, petroleum and petrochemical, and coal chemical.
At present, there are characteristics of high dust, high temperature, and high corrosion in the field of nitrogen oxide monitoring in China. In response to these special working conditions, Hangzhou Shanghang has launched the SH-CEMS2001 series industrial waste gas online continuous monitoring system specifically for the denitrification industry, based on years of experience in flue gas monitoring and industrial process gas analysis. This system is an online monitoring system independently developed by the company, providing a good solution for continuous monitoring of harmful flue gas and accurate basis for denitrification process control.

Scheme composition:
In this scheme, the data collection, data processing, and system monitoring units are designed in layers, and the network topology principle is shown in Figure 1.


The top-level data monitoring layer is the data monitoring center, which consists of one or more industrial control computers, realizing real-time display, storage, printing and other functions of data, and sharing data through the network. The middle layer is the data processing layer, which is composed of multiple programmable controllers according to the system requirements. CLK (or PC-LINK) data communication is used according to the operating conditions. The bottom layer is the data collection layer, and the data collection terminal is directly attached to the data collection point. Through fieldbus, the entire system can form a distributed tree network data acquisition system, and the bus transmission distance connected to each node can reach 1200m.
The monitoring data mainly includes the concentration monitoring of gaseous pollutant emissions (SO)₂、 NO_x、 CO、 CO₂There are two main categories of monitoring: temperature, pressure, flow rate/flow rate, oxygen content, humidity, etc. The monitoring scenario is shown in Figure 2.


System performance:
1) Key indicators can be automatically monitored and alarmed online;
2) Using waterproof aviation joints, easy installation and maintenance, good waterproof and dustproof performance;
3) Powerful software processing capabilities: Real time display, storage, over limit alarm, SMS alarm, data analysis, and print output of various monitoring data have been achieved;
4) Single bus real-time data transmission, simple wiring, low maintenance cost, and high system stability;
5) Fault self check, dual machine hot backup, and backup power supply ensure the stability and reliability of system operation;
6) Distributed network structure, some instrument failures do not affect system operation, and the system has good scalability.
(Editor in charge: admin)