Membrapor’s application guide presents all applications for which we provide outstanding sensor technology, along with the corresponding sensors.
Biogas and landfill gas
Biogas is a combustible gas mixture that is produced, among other things, by the anaerobic digestion of organic materials such as plant residues, food waste or liquid manure. The mixture consists of 40–70 % CH4, 15–60 % CO2 and traces of other gases such as H2S. The latter gas is undesirable because it has a pungent odor, attacks materials and can damage equipment. It occurs in the ppm range. To use the biogas for electricity generation, H2S is first filtered through activated carbon.
Flue gas and exhaust gas
The combustion of hydrocarbon-based fuels, such as coal or wood, produces flue gas that consists mainly of CO2 and H2O. However, undesirable and toxic gases such as SO2, NO or NO2 also occur as traces. These gases must be monitored to measure the efficiency of the systems and their environmental friendliness.
Air quality monitoring
The monitoring of environmental pollutants in the air has developed considerably since the early 2000s. In urban areas in particular, the aim is to protect the population from constant exposure to pollutants. In addition to particulate matter (PM2.5, PM10), this also includes the gases CO, NO, NO2, O3, SO2 and volatile organic compounds (VOCs).
Odor emissions
Odor emissions are caused by the release of gaseous substances of biological, chemical or industrial nature. Sources of such emissions include landfills, waste incineration plants and sewage treatment plants. Sulphureous substances such as H2S or mercaptans are perceptible and disturbing even in the smallest quantities. Especially in warm areas, there are clear limit values for the measurement of H2S and NH3 (e.g. Chile DS Nº 90/2000 or EU 2010/75). The low limit values are important to protect the population and the climate.
Disinfection and sterilization process
Disinfection reduces the bacterial count to a level where infections no longer occur. Germs are completely removed during sterilization. Both processes can be carried out in different ways. Most chemical disinfection processes use Cl2, ClO2, H2O2 or alcohols (Alc). Ethylene oxide (ETO) or CH2O are frequently used in terilization processes. All these substances are toxic and residual values – especially in closed rooms – must be monitored.
Semiconductor industry
In the semiconductor industry, electronic components are manufactured based on silicon wafers. The properties of the semiconductors are modified through targeted doping. Hydrides such as AsH3, B2H6 or PH3 are used for this purpose. Acids such as HCl or HF are used in etching and cleaning processes. Due to their high toxicity, they must be strictly monitored to ensure personal and equipment safety.
Medical applications
The most important gas in medicine is O2 and is used for ventilation. One of the most important areas for electrochemical sensors is their use in non-invasive diagnostics. The presence of certain gases in the breath is an indication of metabolic diseases. The detection of hydrogen (H2), ammonia (NH3) or hydrogen sulphide (H2S) can be used to detect lactose intolerance, liver dysfunction or intestinal dysbiosis.
Industrial safety and personal protection
Gases are omnipresent in industrial processes, either as a product, by-product or starting material. Monitoring them is particularly important for personal safety. Gases are monitored in various industrial processes. A typical application is the measurement of leaks such as chlorine (Cl2) or ammonia (NH3). In addition to fixed installations, portable devices are also frequently used.
Food and beverage industry
Food is often at risk of spoilage during processing, storage and transportation, which requires the use of fast and effective quality assessment technologies. Food quality control is of paramount importance as it is directly linked to people’s health and well-being as well as to the reduction of food waste. In addition, the food industry uses a variety of gases for different applications that play a crucial role in the production, preservation and safety of food. Gases like C2H4 are used to control ripening process. SO2 for example is widely used as a conservation gas.
Energy industry
In the energy industry, a variety of gases are involved in different areas such as power generation, oil and gas exploration, refining and renewable energy. These gases can be either important fuels, by-products or pollutants. SF6 for example is widely used as insulator gas. Because of its extraordinary high greenhouse potential, leaks need to be detected. Other gases such as O2, NOx or CO are measured in combustion processes to quantify the efficiency of the energy-generating process.
Agricultural industry
In the agricultural industry there are many processes where gases are released or used. NH3 is formed when animal feces and urine are decomposed in farms. It is pivotal to monitor the emissions to maintain animal and environmental safety. Other gases such as PH3 are commonly used as fumigation agents to reduce insect infestation.
Confined spaces
Confined spaces such as garages or tunnels require a ventilation system to maintain exhaust gas levels to a minimum. For garages many countries have legislations in place which determine safety and fire protection measures, constructive topics or maximal allowance values for gases (e.g. Germany: GarVo, USA: OSHA). CO and NO2 are both continuously measured in garages. For well-ventilated places the values are typically below 10 ppm for CO and below 0.1 ppm for NO2.