Cogeneration technology for greenhouses based on combustion of natural gas in internal combustion engines is truly green technology. The engines generate heat to allow vegetables to grow in cooler climates, they provide electricity to power the greenhouse and they enhance the concentration of CO2 required by plants to grow. However, the exhaust gas of the engines also contains small quantities of nitrogen oxides (NOx) and traces of ethylene.
By law, NOx must be reduced to 10 ppm and less than 400 ppb ethylene can be tolerated by the crops so installation of emission control equipment is necessary. Johnson Matthey has developed specific SCR systems for greenhouse applications. These emission control systems contain SINOx® SCR catalysts as well as oxidation catalysts. The SINOx® SCR catalysts reduce the nitrogen oxides in the exhaust gases to nitrogen and water and the oxidation catalysts control CO and ethylene (C2H4) to the acceptable levels.
