Alternative fuels have been getting more attention as concerns escalate over exhaust pollutant emissions produced by internal combustion engines, higher fuel costs, and the depletion of crude oil. Various solutions have been proposed, including utilizing alternative fuels as a dedicated fuel in spark ignited engines, diesel pilot ignition engines, gas turbines, and dual fuel and bi-fuel engines. Among these applications, one of the most promising options is the diesel derivative dual fuel engine with Alternate fuel as the supplement fuel. In present study we are using Ethanol as alternate fuel with Diesel to investigate the Dual fuel model with non-premixed & premixed combustion and compare on the basic of combustion efficiency and pollutant emissions rate like carbonic oxides and nitric oxides. Ethanol is taking as an Alternate fuel which is cheaper in cost and easily available as compare to the conventional fuels. CFD Results shows a excellent flow phenomenon which is stable in nature and due to this the accuracy of the simulation results are higher for layer formation system in combustion. The pollutant emissions (Carbonic oxides) are decreasing in non premixed combustion as compare to the premixed combustion that shows the complete combustion rate is increased. NOx emissions are also decreasing in Non-premixed dual fuel (Diesel + Ethanol) model as compare to premixed combustion. In second part of the study we are using Chemkin (Chemical kinetic) mechanism for evaluating the NOx pollutant which is responsible for thermal NOx . CFD Simulation results inTable no. 2 are clearly shows that mass fraction of NO, NO2 and N2O is decreasing in Non premixed type of combustion. In current work we are taking Ethanol as a Alternate fuel which is cheaper in cost and easily available as compare to the conventional fuels.