When burning fossil fuel or wood, there would always be pollutant. But some technology claims that it could redece pollution by decreasing the burning temperature. Is that true? And can any one give me a source that detailed why it happen or not happen?
generally NOT true. Chemically speaking, higher temperature combustion of a fuel in oxygen tends to go more thoroughly to completion compared to lower temperature combustion.
However, higher temperature combustion tends to produce more oxides of nitrogen, which are considered pollutants.
Therefore, minimization of pollutants in the exhaust stream of a combustion process is a compromise between minimization of unburned or partially-combusted fuel and minimization of NOx creation.
Combustion of hydrocarbons in presence of air (mixture of Oxygen and Nitrogen) at high temperature (and pressure) will lead to the production of nitrous oxides, which are a group of pollutants. As you lower the combustion temperature by some means, even though the nitrous emissions would decrease, the fossil fuel combustion would tend to produce more unburned hydrocarbons, soot particles and carbon monoxide, which are another group of pollutants. Pollutants are produced as you move along both sides of temperature axis.
The claim of pollutant reduction by decreasing temperature must be seen in this context.