Cogeneration is a simultaneous production of electrical and thermal energy resulting from maximum use of primary energy (natural gas or biogas) by use of systems that ensure maximum energy efficiency and do not release to the environment, but recover and enhance heat produced by an endothermic engine (or turbine).
Producing electrical energy by a cogeneration system is very advantageous compared to simply purchasing energy; furthermore, it allows to make maximum use of heat generated by engine cooling processes: hot water can be released directly into the production cycle and used to warm up work areas, while the high heat generated by exhaust fumes can be used to generate steam or heated water, to warm up the diathermic oil, or for other needs.
Cogeneration reduces energy costs up to 30% and improves the public image of companies and factories. Furthermore, it contributes to creating an environmentally sustainable system that is in synch with European and national directives, as well as global objectives aimed at safeguarding the environment.
There are gas naturally present in oil wells. Gas is predominantly composed by methane which is in liquid form when mixed with oil, and become gaseous as it approaches the surface. Presence of gas is a problem during mining and oil extraction because any leak may saturate the entire work area.
This is, essentially, a “waste gas” which is present in the underground where is it subject to strong pressure; gas is mixed with oil producing a hydrocarbon slurry, which also include other gases like butane and propane. Deep in the ground, it is in liquid form, but as it approaches the surface and pressure decreases, methane is turned into gas. If a system is not fitted for treatment and therefore, for enhancement of this waste, the latter is released to the atmosphere, where it must be burned to prevent air saturation around the well, therefore, preventing the risk of uncontrolled explosions.
This gas is subject to massive waste, not to mention how great are environmental and financial damages it can cause: flare gas also causes a negative impact on the ecosystem, if you think that burning in the air only 5% of methane gas extracted from oil wells in a year,releases to the atmosphere the same amounts of carbon dioxide produced by more than 80 million mid-size vehicles.
Flare gas can also present many opportunities if properly controlled and managed; in particular, it can be used to power cogeneration systems.
Cogeneration is the ideal technology to transform flare gas from a problem into a resource it is possible to transform flare gas in electricity to be used during extraction and mining processes (in particular, for pumping stations, both for gas and oil), while any excess amount can be released to national electricity distribution systems, used for oil separation processes on site, and to keep oil fluid during pumping operations.
Coal mining produces gas methane which, for safety reasons, as well as for the advantageous financial opportunities it offers, can be put to good use via cogeneration. For this reason, mining companies are now more than ever looking at cogeneration systems.