Selective Catalytic Reduction For Flower Plants
The process that is used to lessen NOx emissions and control air pollution is called Selective Catalytic Reduction. The harmful emissions are converted into nitrogen and water. This process involves catalytic reactions of either ammonia steam or air injected into exhaust pipes holding the NOx gases. The gases then mix thoroughly reducing the NOx once they pass through the catalytic bed. The catalyst main function is to promote the reduction of the NOx and this does not affect it. In general, the by-product produced when urea acts as a reducing agent is referred to as Carbon Dioxide. This technology reduces the emissions of NOx by 70 to 95 %.
Power plants usually discharge huge volumes of the NOx gases as the power that is used is acquired from ignition of fuels. With this technique, these emissions have been reduced considerably. The process is made up of the reactor chamber, the catalyst bed, which holds the catalyst modules as well as an Ammonia injection grid system.
During the process, an ammonia steam or even air is injected into the exhaust pipes, which contain the NOx gases. The ammonia passes through the catalytic bed helping in the reduction of nitrogen oxides as well as non-malignant nitrogen gas. The technique uses different agents including aqueous ammonia, urea and anhydrous ammonia. Apart from urea, the other agents are known to have certain disadvantages.
The disadvantage in this technique arises when there is ammonia slip. This is when ammonia that has not been used finds its way into the air. This can occur when the required temperatures not maintained or if more that the required ammonia is released into the system. An additional disadvantage comes by when ammonium bisulphate or sulfate are emitted. These result from the excess ammonia combining with the sulfates contained in the air. These sulfates have been proven to cause inflammations and coughs.
Proper use of selective catalytic reduction has various benefits. For instance, coal fired boilers fitted with the system have been able to reduce 60% to 65% of NOx emissions. Gas fired utilities on the other hand have achieved more than 90% reductions.
This system originally began in the United States with the Engelbert Corporation in 1957, by then it was not tested. This system then continued with developments in Japan and United States in the early ’60s, where the research mainly focused on catalyst agents that were more durable and cost friendly. In 1978, the IHI Corporation installed the first system.
Various ceramic materials can be used to produce the catalysts. They include, Titanium Oxide. These catalytic components are basically oxides that are obtained from the base metals zeolites and precious metals. Base metal catalysts are the cheapest but least durable.
Best content writer in association with Cormetech Inc., the leading producer of titania-based ceramic honeycomb catalyst for NOx emissions control and NOx reduction used in Selective Catalytic Reduction (SCR) systems for air pollution control.
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