Fuel Gas Heaters
If you are a company that deals with gas turbines, then you know how important it is to use fuel gas heaters as a part of your fuel gas conditioning system. Turbine and combustion turbine fuel gas requires proper treatment in order for it to perform up to standards and also in order to increase its longevity. You may also need fuel gas heaters as part of a fuel gas conditioning system in order to meet specific requirements to maintain the warranty of the gas turbine.
The way the conditioning system works is that it removes contamination at three different levels before the gas is superheated by the fuel gas heaters. Contaminants removed are solids, liquids and gas. Some of the solids that are removed are sand, rust, and scale. If these contaminants are allowed to remain in the gas, they can make deposits and cause erosion in the hot section of the turbine.
Liquid contaminants can also cause a hot spot in the combustor and leave deposits on the injector as well as causing missed emissions. Some of these contaminants can be water, heavy hydrocarbon, condensed gas, and even lube oil from an upstream reciprocating compressor. These must be removed by the fuel treatment system before superheating.
Even some gas must be removed as it can cause deposits and corrosion of the hot section of the turbine. Some of the offending gasses include hydrogen sulfide and siloxane. These must be removed prior to combustion.
Both solid and liquid contamination can be removed by a system that will utilize extremely efficient coalescing filters. Once these contaminants have been removed, the gas will be superheated by the fuel gas heaters. Often, the gas is heated above the dew point, and then it may be superheated based on the requirements. For instance, a gas turbine may need 50 degrees of superheat, so the heater will provide that additional heating before the gas enters the turbine.
It is important for the gas to be heated above the dew point so that the water vapor won't condense out and become liquid before the gas gets to combustion. This is another reason that water is removed during the cleaning and contaminant removal phases of the fuel gas conditioning system.
Most fuel gas heaters are designed to use low wattage for longevity. They may also have digital temperature controls so that they can maintain the required tight temperature, and they should be insulated well against heat loss. You also want to find heaters that are designed to be extremely efficient and to produce no emissions.