Ammonia Leakage Detection and Application of Ammonia Sensors
With the improvement of people's living standards and the rapid development of industrial economy, ammonia emissions from all walks of life into the atmosphere have been increasing in China in recent years. The rising ammonia concentration has an increasingly obvious impact on the climate. On the one hand, atmospheric ammonia reacts with gaseous pollutants such as sulfur dioxide and nitrogen oxides to form secondary aerosol particles, which absorb and scatter light and reduce atmospheric visibility. On the other hand, ammonia discharged into the atmosphere acts as a greenhouse gas and affects atmospheric temperature. Therefore, the market demand for gas sensors is growing continuously. The research and development of gas sensors, especially ammonia sensors for detecting toxic and harmful gases, have achieved rapid development.
Ammonia is a colorless gas with a strong pungent odor, lighter than air and highly soluble in water. Its aqueous solution is alkaline. In laboratories, ammonia is generally prepared by heating the solid mixture of ammonium chloride and slaked lime, with calcium chloride and water as by-products.
Ammonia has important industrial applications, yet it is extremely harmful to human health in homes and offices. Short-term inhalation of large amounts of ammonia will cause symptoms such as lacrimation, sore throat, hoarseness and cough, accompanied by dizziness and nausea. Severe cases may suffer from pulmonary edema and acute respiratory distress syndrome. Excessive inhalation or long-term exposure to ammonia may lead to skin pigmentation and finger ulcers. After entering the lungs, ammonia easily enters the blood through alveoli, binds with hemoglobin and damages the oxygen transport function of human body. Alkaline substances cause deeper and more serious damage to human tissues than acidic substances. It will also cause excessive ammonia concentration in blood, trigger cardiac arrest and even threaten life safety. So where does ammonia in living and working environments come from?
Relevant experts pointed out that indoor ammonia mainly comes from concrete admixtures used in construction, which are divided into two major sources. The first source is concrete antifreeze agents such as urea added into cement during winter construction. Such substances release ammonia slowly from laminated boards and cement, resulting in long-term ammonia residue indoors, which is common in northern China. The second source is high-alkali concrete expanding agents and early strength agents used to speed up concrete solidification, which is the main cause of ammonia pollution in southern China. In addition, indoor ammonia also derives from interior decoration materials. Most additives and whitening agents used for furniture finishing adopt ammonia water, which has become a common material in the building materials industry.
Ammonia has a strong pungent smell with a density of 0.7710 and a relative density of 0.5971 (air=1.00). It can be easily liquefied into colorless liquid under normal temperature and pressure, with a critical temperature of 132.4℃ and a critical pressure of 11.2 MPa. It can also be solidified into snow-like solid with a melting point of -77.75℃. It is soluble in water, ethanol and ether. It decomposes into nitrogen and hydrogen at high temperature with reducibility, and can be oxidized into nitric oxide with the help of catalysts. It is widely used to produce liquid ammonia, ammonia water, nitric acid, ammonium salts and amines, and can be directly synthesized from nitrogen and hydrogen. Ammonia can burn the mucous membranes of skin, eyes and respiratory organs; excessive inhalation will cause pulmonary swelling and even death.
Since harmful ammonia may exist around our daily life and work, effective improvement measures must be taken. Ammonia sensors are applied to monitor ambient ammonia concentration. Through linkage control, they can realize environmental improvement and safety protection.
At present, ammonia sensor detection is one of the most widely used gas detection technologies. In short, ammonia sensors work on the electrochemical principle, and calculate the actual gas concentration by measuring the induced current.
Shenzhen Wuliang Sensor Technology Co., Ltd. mainly sells British imported DDS electrochemical ammonia sensors. These sensors require no bias voltage, featuring easy operation and high cost performance. They are ideal detection equipment for staff working in harsh environments and trustworthy gas sensors for all users.
Main Features of Ammonia Sensors
Optional measuring ranges: 0-100ppm, 0-300ppm, 0-1000ppm
Corresponding overload resistance: 200ppm, 500ppm, 1500ppm
High stability, 4-series and 7-series available
Strong environmental adaptability
Ammonia sensors are mainly used to detect and display ammonia concentration. Matched ammonia gas alarms adopt microprocessor as the control core and high-performance electrochemical sensing elements, featuring high sensitivity and fast response speed. The alarm will sound timely once ammonia concentration exceeds the safety standard. Consisting of gas alarm controllers and detectors, these products are widely used in metallurgy, petroleum, petrochemical industry, chemical industry, light industry, coking industry, municipal engineering, gas supply, pharmaceutical industry, sewage treatment and other special industries.
In conclusion, ammonia is a substance with both practical value and potential dangers. Although it plays an important role in various fields, its biological toxicity has been fully confirmed by scientific research, becoming a hidden health hazard for human beings. Its adverse environmental impacts also deserve more attention. With the continuous upgrading of gas sensor technology, new application scenarios and market demands will keep emerging, driving the steady development of the gas sensor industry. It will bring users eco-friendly, safe, healthy, convenient and high-value application experiences and benefit the public greatly.
