subject: Why Detecting Gas Is So Important To The Processing Industries [print this page] The processing environment employs various types of sensors for the detection of gas leaks. Some of the common types are ultrasonic detectors, semiconductor detectors, and infrared point detectors, in addition to electrochemical detectors.
After gas leak detection started making headlines, people started learning about the harmful effects that some gases have on human health. Before the use of electronic sensor, people utilized less precise ways of measurement. One way consisted of miners using canaries as a warning system and for early detection of harmful gases, such as carbon monoxide.
This method entailed taking the normally chirpy bird down within the mines where they worked. If the bird stopped chirping and eventually died, this alerted them to exit.
Another detection system used before electronic sensors, involved using a chemically infused paper to detect carbon monoxide. When the gas was present, the paper would turn brown. This method was common within the eighties and nineties. However, advancements in technology have contributed to increases in the options available for monitors and detection systems.
Infrared point detectors
Infrared point detectors are a type of CO2 detector, used for detecting the presence of carbon dioxide. The detector works by using radiation, which passes through a volume of gases in order to detect leaks. Any energy that passes through the radiation is absorbed at certain wavelengths. The amounts of wavelengths absorbed depend on the chemical properties.
Detection of this type of gas within process environments is vital, due to how it becomes toxic in high concentrations. CO2 levels higher than 1% can cause some people to start feeling drowsy.
Levels of CO2 detected within 7% to 10% can cause symptoms, such as headache, unconsciousness, as well as dizziness, along with hearing and visual dysfunction. Some people can become unconscious within the first few minutes, while for some it may take an hour.
Various Uses
Often, CO2 utilised within the oil, chemical, as well as food industries. In most cases, it is used in areas that require pressurized gas. In general, CO2 has the advantage of being nonflammable, as well as having a low cost. Additionally, it has the advantage of allowing for the use of more CO2 in areas that usually would not allow for if any other gas.
Mainly, this has to do with how it goes from a gas to a liquid at room temperature. One example of its use is within aluminum capsules for things as paintball guns. Additional uses include killing pests, as well as for blasting purposes within coalmines and within pneumatic systems.
Electrochemical Detectors
These types of detector work by allowing the gases o diffuse through a porous membrane to an electrode, which it is either reduced or oxidized. How much of the gas that is oxidized at the electrode determines how much of a current is produced. This current enables the sensor to detect the amount of concentration that is present as a gas. Often, they work well for the detection of carbon monoxide and other types of toxic gases.
Some key advantages with electrochemical detectors have to do with the customization offered. However, electrochemical detectors are only useful with electrochemically active gases. In any case, this type of detector tends to offer more stability, in addition to reliability over time in comparison to others.
However, they are subject to corrosive elements that are within the environment, which may lead to them lasting only one or two years.
Types of uses
Often, an electrochemical detector is used within a wide variety of environments. More specifically, they are used within places such as gas turbines, refineries, chemical plants as well as underground gas storage facilities, in addition to many other types of places.
Hydrogen Sulfide Detector
H2S detectors are imperative within the processing environment. One of the main reasons for this has to do with the corrosive and toxic nature of hydrogen sulfide. Therefore, this type of detector is constantly under development. This type of detector uses a solid-state semiconductor in order to detect the presence of this type of gas.
Types of uses
Often, this type of gas is used within oil refineries, sulfur recovery plants, as well as chemical plants, compressor stations, and LNG plants. Some of the other areas this type of gas detection is needed is such places such as gas turbines, in addition to sewage and water treatment plants.
