With the rapid development of industrial production and enterprises, pollution from industrial waste gas emissions has become a prominent environmental issue in China. At present, waste gas is a major source of air pollutants. Large volumes of industrial waste gas discharged into the atmosphere degrade ambient air quality, pose severe threats to human health, and cause substantial losses to the national economy.
In recent years, factories have attached growing importance to the monitoring of toxic gases during chemical production processes. Nitrogen dioxide (NO₂) is an important industrial gas. It can be used as an industrial water treatment agent, as well as for bleaching pulp and fibres, refining flour, oils and sugar, and depilating leather. Meanwhile, nitrogen dioxide is a toxic gas. It is reddish-brown, paramagnetic, pungent-smelling and readily soluble in water. Low concentrations (4 ppm) of nitrogen dioxide can numb the nasal tract and may lead to excessive inhalation. Long-term exposure to NO₂ at concentrations of 40 to 100 mg/m³ will cause serious health damage. Therefore, real-time monitoring of nitrogen dioxide in factories is essential to protect the health of staff and ensure smooth production.
Instruments for NO₂ monitoring mainly include analytical devices based on optical methods such as the Saltzman method and chemiluminescence. Although these instruments can deliver accurate analytical data, most of them are large-scale analytical equipment with high operating costs and routine maintenance requirements, making them unsuitable for indoor monitoring in factories. Electrochemical NO₂ gas sensors are widely adopted nowadays. Nitrogen dioxide sensors feature small size and low cost. They can simply and rapidly detect nitrogen dioxide concentrations in the environment, enabling the automation and miniaturization of monitoring equipment.
Industrialized society has brought rapid technological advances, yet it has also triggered serious environmental problems such as air pollution. Humans breathe air every moment, and air quality exerts a profound impact on our health. However, emissions from vehicle exhaust and industrial waste gas are directly released into the air, causing air pollution and triggering a variety of health problems. This makes it particularly urgent to develop low-cost, high-efficiency and high-sensitivity sensors to detect pollutant gases in the air.
Industrial waste gas refers to the general term for various pollutant-containing gases discharged into the air during fuel combustion and production processes within factory premises. Such waste gas includes carbides, sulphides, fluorides, nitrogen oxides, smoke and dust. These harmful gases enter the human body through the respiratory tract in different ways. Some cause direct harm to humans, while others have cumulative effects that inflict more severe damage to human health, with different substances producing distinct impacts.
Industrial waste gas purification refers to the pretreatment of waste gas generated at industrial sites such as factories and workshops, so that discharged gas meets national waste gas emission standards. Purified waste gas usually requires testing to verify compliance with emission limits.
Currently, most online industrial waste gas monitoring systems on the market adopt a one-to-one measurement approach for industrial waste gas containing multiple gas components. Nevertheless, industrial waste gas comprises numerous gas species, and a single meter in online waste gas monitoring systems can only detect one type of gas. To monitor various gases within complex gas mixtures, multiple types of meters must be installed for simultaneous measurement. This one-to-one meter monitoring solution not only wastes cost and space but also increases the workload of maintenance personnel for each instrument.
Shenzhen Wuliang Sensor Technology Co., Ltd. supplies British DDS nitrogen dioxide sensors. The standard Series 4 / Series 7 models are designed for industrial leakage detection, while Series 3 and Series 5 products are applied to emission monitoring, delivering reliable protection for users and industrial applications.
