Urea Solution Diesel Exhaust Gas Treatment Fluid Adblue Catalyst
Diesel exhaust fluid (DEF) is an aqueous urea solution made with 32.5% urea and 67.5% deionized water. DEF is used as a consumable in selective catalytic reduction (SCR) in order to lower NOx concentration in the diesel exhaust emissions from diesel engines.
CR systems are sensitive to potential chemical impurities in the urea solution, therefore the solvent is demineralized water. The urea solution is clear, non-toxic and safe to handle. However, it can corrode some metals and so must be stored and transported carefully.
DEF is stored in a tank on board the vehicle, and injected into the exhaust stream by a metering system. The injection rate depends on the specific after-treatment system, but is typically 2-6% of diesel consumption volume. This low dosing rate ensures long fluid refill intervals and minimises the tank’s size (and subsequent obtrusion into vehicle packaging space). An electronic control unit adjusts the addition of fluid in accordance with such parameters as engine operating temperature and speed.
Diesel engines can be run with a lean burn air-to-fuel ratio (overstoichiometric ratio), to ensure the full combustion of soot and to prevent them exhausting unburnt fuel. The excess of air necessarily leads to generation of nitrogen oxides (NOx), which are harmful pollutants, from the nitrogen in the air. Selective catalytic reduction is used to reduce the amount of NOx released into the atmosphere. Diesel exhaust fluid (DEF) from a separate tank is injected into the exhaust pipeline, where the aqueous urea vaporizes and decomposes to form ammonia and carbon dioxide. Within the SCR catalyst, the NOx are catalytically reduced by the ammonia (NH3) into water (H2O) and nitrogen (N2), which are both harmless; and these are then released through the exhaust.
DEF is a 32.5% solution of urea, (NH2)2CO. When it is injected into the hot exhaust gas stream, the water evaporates and the urea thermally decomposes to form ammonia and isocyanic acid.
The overall reduction of NOx by urea is:
2 (NH2)2CO + 4 NO + O2 → 4 N2 + 4 H2O + 2 CO2 and
2 (NH2)2CO + 3 NO2 → 2 1⁄2 N2 + 4 H2O + 2 CO2
Executive Standard: GB 29518-2013
With a registered capital of CNY 88 million, Mingshuo Environment Technology Group Co., Ltd. is founded in 2004. It is a high-tech enterprise dedicated to purifying sulfur-containing gases and realizing high-value utilization of organic wastes.
Adhering to the corporate spirit of integrity, innovation and mutual benefit, Mingshuo has gradually developed into a high-tech enterprise integrating R&D, consulting, design, manufacturing, construction and operation. It can provide comprehensive and sustainable ”one-stop” environmental services and overall solutions. The Group has passed ISO quality control, environmental management, occupational health and safety management system certifications, has professional construction qualifications for environmental engineering, D type pressure vessel manufacturing qualifications. It is also “Weifang Enterprise Technology Center”, “Weifang City Desulfurization and Denitrification Engineering Laboratory”, “Weifang City Biogas Equipment Engineering Technology Research Center”. The products have won the honorary titles of “China Green Products” and “China Famous Brand”. The chairman of the Group won the honorary title of “Shandong Province Circular Economy Person of the Year”.
Mingshuo’s products are divided into three series: desulfurizer and desulfurization equipment, biogas equipment, titanium, nickel and the like pressure vessel equipment. The desulfurizer and desulfurization equipment are mainly used for the treatment of biogas, natural gas, oilfield associated gas, shale gas, and other sulfur-containing gases for users in the fertilizer, coking, steel plant, and petroleum refining industries. The biogas equipment is mainly used for the treatment of organic waste such as livestock and poultry manure, kitchen waste, organic waste, straw and sewage. It realizes high-value utilization and turns waste into treasure. Titanium, nickel and the like pressure vessel is mainly used in oil refining, pharmaceutical, fertilizer, desalination, chemical and other industries. The Group has long-term cooperation with large domestic enterprises such as CNPC, Sinopec, COFCO, CSSC, Energy China, Beijing Drainage Group, INFORE ENVIRO, China Huadian Corporation Ltd., and Weichai Group. The Group has independent import and export rights, and has provided complete system services for lots of customers in the United States, Japan, Malaysia, the Philippines and other countries along the Belt and Road.
Mingshuo Environmental Group is committed to the development of environmental undertakings, always adhering to the development concept of “Cherish the Limited, and Create the Infinite”, and wish to go hand in hand with you to create a better future!