In the production environment of chemical plants, all kinds of chemical reactions occur frequently, toxic and harmful gas leakage, abnormal equipment operation and so on. The stability of oxygen concentration is directly related to production safety and personnel health. As the core equipment for accurate monitoring of oxygen concentration, oxygen sensor plays an irreplaceable role in the safety production system of chemical plants.

The production workshop of a chemical plant is an important area for oxygen sensor applications. The equipment here is dense and the personnel are concentrated. A large amount of oxygen may be consumed during the chemical reaction, or the oxygen space may be occupied by the leaked ammonia, chlorine and other toxic gases, resulting in a sudden drop in local oxygen concentration. For example, in the synthetic ammonia workshop, ammonia will spread rapidly after leakage. If it is not monitored in time, when the oxygen concentration is lower than 19.5, the on-site operators will have symptoms of hypoxia such as dizziness and nausea, and even coma in severe cases. The oxygen sensors installed in different positions of the workshop can capture the change of oxygen concentration in real time. Once the value is lower than the safety threshold, the sensor will immediately trigger the sound and light alarm, and transmit the signal to the central control room to remind the staff to evacuate and take ventilation measures.

The storage tank area is also a key point for the oxygen sensor. A large number of flammable, explosive or toxic chemicals, such as methanol, ethanol and sulfuric acid, are stored in the tank farm. Some chemicals may volatilize during storage to produce gases that can change the oxygen concentration in the surrounding environment if the tank is not tightly sealed. Taking a methanol storage tank as an example, methanol is volatilized and mixed with air, which may not only form an explosive mixture, but also reduce the surrounding oxygen content. The oxygen sensor is installed at the monitoring point around the storage tank and can be monitored 24 hours a day. When an abnormal oxygen concentration is detected, in addition to issuing an alarm, it can also link the explosion-proof ventilation equipment in the tank area to automatically open the fan to accelerate air circulation and reduce safety risks.

In the limited space of the chemical plant, such as the reactor, underground pipeline, cellar, etc., the role of oxygen sensor is more prominent. These spaces are poorly ventilated, prone to the accumulation of harmful gases, and the oxygen concentration is often in an unstable state. Before working in the confined space, the personnel shall carry a portable oxygen sensor for inspection. Make sure that the oxygen concentration is within the safe range of 19.5-23.5%. During the operation, the sensor continuously monitors, and once the concentration is abnormal, the operator can be reminded to evacuate in time. Once, when a chemical factory employee was cleaning the reactor, he did not detect the oxygen concentration in the reactor and suffocated due to lack of oxygen after entering. Fortunately, the oxygen sensor he carried with him gave an alarm and was rescued by external personnel in time, thus avoiding the tragedy.

The oxygen sensor can also realize intelligent linkage with the safety control system of the chemical plant. When the sensor detects that the oxygen concentration is too high and is in an oxygen-rich state, the system will automatically shut down the nearby open fire equipment to prevent fire caused by sufficient oxygen; if the concentration is too low, in addition to starting the ventilation equipment, it will also shut down the relevant chemical reaction device. Avoid the hypoxia environment to affect the reaction process and even cause danger. This linkage mechanism forms a complete safety closed loop, which greatly improves the emergency response capacity of the chemical plant.

In terms of selection, chemical plants need to select appropriate oxygen sensors according to different scenarios. The production workshop and storage tank area are suitable for installing fixed sensors, which have the characteristics of high protection level and strong stability, and can adapt to the complex environment of chemical plants; portable sensors are convenient for staff to carry, and are suitable for limited space detection and inspection work. At the same time, the sensor needs to have anti-interference ability, can work accurately in the environment of dust and high humidity, and ensure the reliability of monitoring data.

Regular calibration and maintenance of the oxygen sensor is the key to ensure its normal operation. Due to the harsh environment of the chemical plant, the detection accuracy of the sensor may be affected. A monthly calibration can ensure the accuracy of the data. In daily maintenance, it is necessary to clean up the dust and stains on the surface of the sensor so that the sensor is always in the best working condition.

With the development of intelligent chemical industry, oxygen sensors are constantly upgrading. The new oxygen sensor combines the Internet of Things technology, which can upload the monitoring data to the cloud platform in real time. Managers can remotely view the oxygen concentration in each area through mobile phones or computers, realizing more efficient safety management. In the future, oxygen sensors with higher accuracy, longer service life and stronger environmental adaptability will provide a more solid guarantee for the safe production of chemical plants.

Here, Shenzhen recommend a lead-free oxygen sensor. The sensor is the exclusive agent of the British brand Alphasense's latest LFO2 lead-free oxygen series. It has reliable performance and has set a new benchmark in innovation and environmental responsibility.

The following are Alphasense long life lead free oxygen sensor LFO2-A1The main parameters:

Model: LFO2-A1(Can directly replace the existing long-life electrochemical oxygen sensor (includingAlphasense LFO2-A4), more durable, better performance)

Range: 0 - 30% VOL

Response time: <10s

Output: 80-130uA (in air)

Lifetime: 5 years

Please consult for details.