Associated gas is considered a by-product from oil production. It is a mixture of inorganic and hydrocarbon compounds that produces "black gold". The main difficulties with its use are caused by the absence in the mining areas of the processing and transport infrastructure, of large local consumers. In this regard, until recently, associated gas, as a rule, was burned, polluting the environment.
Moreover, due to the fact that it contains ethane, propane, methane, butane, isobutane and non-hydrocarbon gases, hydrogen, helium, nitrogen, argon, hydrogen sulfide, dust of solid rocks, its combustion products cause a number of serious illnesses. However, toughening laws in the countries of the former USSR put the extractive industry in an almost uncontested situation - associated gas should be utilized with the obligatory generation of electricity or with additional treatment and supply to the main networks. From the point of view of the economy, the first option is most acceptable, the second makes sense if consumers are located at a relatively short distance.
Associated gas can also be used as fuel for internal combustion engines. True, in this case, there are certain limiting factors. In particular, associated gas requires some preparation for use, since it contains hydrocarbons with a low methane number, which are the cause of detonation. In addition, it contains aggressive sulfur-containing substances that cause corrosion and rapid oxidation of the oil.
Natural and associated gas today are competitors, but not in terms of consumer demand, but in terms of access to a single gas transmission system. Due to its heavy workload and monopoly on infrastructure, access to it by oil companies is limited. All this practically nullifies all the economic advantages that associated gas has, which, in particular, include the established zero mineral extraction tax rate and the cost of production. With all this, the price of this gas is low, it depends mainly on its composition. When determining it, the costs of storage and transportation are practically not taken into account.
The use of gas as a fuel for generating heat and electricity at the production site in this situation becomes almost the only way to use it. For this purpose, the following equipment package is required:
- gas treatment unit (there may be one stationary unit for the entire facility, consisting of modules, the number of which will depend on the number of power units);
- gas piston electrical installation;
- a unit for utilization of thermal energy of the engine and exhaust gases ;
- terminal for liquid fraction.
The design of gas treatment equipment is carried out depending on its specific composition. The electric generator and auxiliary installations can be made both in block (container) execution, and in open. Equipment can also be located on
trailed devices for use as backup mobile or permanent sources of electrical power.