IJSRD - International Journal for Scientific Research & Development| Vol. 2, Issue 03, 2014 | ISSN (online): 2321-0613 All rights reserved by www.ijsrd.com 585 Performance & Emission Analysis of Urea Based Catalytic Convertor in CI Engine Mr. Raj. H. Padhiyar 1 Anup. B. Patel 2 Tushar. M. Patel 3 Gaurav. P. Rathod 4 1 M. E Student 2,3,4 Assistant Professor 1,2 Mechanical Engineering Department, LCIT Bhandu. 3,4 Mechanical Engineering Department, LDRP Gandhinagar. Abstract—Better fuel economy and higher power with lower maintenance cost has increased the popularity of diesel engine vehicles. Diesel engines are used for bulk movement of goods, powering equipment, and to generate electricity more economically than any other device in this size range. The diesel engine is typically more efficient than the gasoline engine due to higher compression ratio. Diesel engines also do not suffer from size and acceleration limitations, which the SI engine is prone to. But now a day’s problems are arise with the energy crisis and air pollution across the world due to the vehicles. Energy crisis increase the demand of fuel economy of vehicles. EGR, WI, WDE, OEC technique displaces oxygen into intake air and lower oxygen concentration in combustion chamber, which lower the flame temperature and increase the specific heat of inlet charge, which control the NO x and improve performance. EGR, WI, WDE, OEC techniques does not give effective result at higher load. It also higher soot deposit on the combustion chamber parts. From the some changes in catalytic convertor it should give some positive result to reduce NO x. There are many work have been done on SI engine using different changes on catalytic convertor. And it gives very positive result on NO x emission and performance.So from analysis of literature survey it concluded that there is good scope of experimental study on CI engine with changes in catalytic convertor. I. HISTORY The catalytic converter was first invented by Eugene Houdry, Who was a French mechanical engineer and expert in catalytic reaction and he was lived in the U.S. around 1950 [1] . When the results of early studies of smog in Los Angeles were published, Houdry became concerned about the role of smoke stack exhaust and automobile exhaust in air pollution and founded a company, Oxy-Catalyst. Houdry first developed catalytic converters for smoke stacks called cats for short [1] .Then he developed catalytic converters for warehouse forklifts that used low grade non-leaded gasoline. Then in the mid-1950s he began research to develop catalytic converters for gasoline engines used on cars. He was awarded United States Patent 2742437 for his work [1] . Widespread adoption of catalytic converters didn't occur until more stringent emission control regulations forced the removal of the anti-knock agent, tetraethyllead, from most gasoline, because lead was a 'catalyst poison' and would inactivate the converter by forming a coating on the catalyst's surface, effectively disabling it [2] . Catalytic converters were further developed by a series of engineers including John J. Mooney and Carl D. Keith at the Engelhard Corporation; created the first production of the catalytic converter in 1973.Dr. William C. Pfefferle developed a catalytic combustor for gas turbines in the early 1970s, allowing combustion without significant formation of nitrogen oxides and carbon monoxide [1] . The first widespread introduction of catalytic converters was in the United States market, where 1975 model year gasoline-powered automobiles were equipped to comply with tightening U.S. Environmental Protection Agency regulations on automobile exhaust emissions. At that time a “two-way” converter is used which combined carbon monoxide (CO) and unburned hydrocarbons (HC) to produce carbon dioxide (CO 2 ) and water (H 2 O). Two-way catalytic converters of this type are now considered obsolete, having been supplanted except on lean burn engines by “three-way” converters which also reduce oxides of nitrogen [2] . II. PROBLEM DESCRIPTION Cars, the dominant source of road transport emissions, are one of the most important contributors to air pollution problems. To reduce the atmospheric emissions from passenger cars, the catalytic converter, and “end-of pipe” solution, was introduced and has become one of the most effective technologies. Since the introduction of cars with three-way catalytic converters, emissions of hydrocarbons, carbon monoxide, nitrogen oxides and other atmospheric pollutants from car exhausts have declined substantially. Catalytic converters(SI engine) are the most effectivemeans of reducing pollutant emissions from internal combustion engines under normal operating conditions. But the future emission requirements cannot be met by three way catalysts (TWC) as they cannot effectively remove hydrocarbon (HC) and carbon monoxide (CO) emissions from the outlet of internal combustion engines in the cold-start behaviour of catalytic convertors [1] .For compression-ignition (i.e., diesel engines), the most commonly used catalytic converter is the Diesel Oxidation Catalyst (DOC). This catalyst uses oxygen in the exhaust gas stream to convert carbon monoxide to carbon dioxide and hydrocarbons to water and CO2. These converters often operate at 90 percent efficiency, virtually eliminating diesel odour and helping to reduce visible particulates. These catalysts are not active for NOx reduction because any reductant present would react first with the high concentration of O2 in diesel exhaust gas. So from the CI engine Nox produce from the emission 350– 1000 ppm [2] . A. Catalytic Convertor In SI Engine [3] There are two types of catalytic convertor which is used in the SI engine. 1) Two Way Catalytic Convertor In two way convertor it was first introduction in the U.S., where 1975 model year automobiles were so equipped to comply with tightening U.S. Environmental Protection Agency regulations on automobile exhaust emissions. The