Today oil refineries in Russia have accumulated large amounts of petroleum coke (petcoke). High content of sulphur, vanadium, nickel and other metals, poor free-running properties, low volatile content in this fuel make its burning via conventional methods rather complicated, and thus, limit its application in the energy sector. To ensure efficient use of petroleum coke in the energy sector, a special technology has been developed for efficient combustion of petroleum coke in a fluidized bed in the form of cavitation coal-water slurry (CCWS). Specific character of petroleum coke as a fuel, namely its low reactivity, significant levels of sulphur and vanadium, high corrosion and slagging properties, define methods and devices for its use in the energy sector. The most common methods used throughout the world for petroleum coke combustion are those for combustion in fluidized bed boilers when sorbent agent is injected into the furnace to fix sulphur and mixed with coal in coal-fired boilers equipped with an efficient desulfurization system. A promising, though a very expensive method, is the application of petroleum coke in an integrated gasification combined cycle (IGCC). It is possible to burn "pure" petroleum coke in conventional coal-fired furnaces of dedicated design suitable for firing low-reactivity coals, this method being not widely spread, though. Typically, these furnaces may be blanketed high-forced combustion chambers, down-shot furnaces or slag-tap furnaces with intermediate bins, with increased height of furnace chamber, high-temperature (up to 400oС) hot air heating and finely ground coal dust in bowl or ball-and-tube mills. Russia has not seen a wide application of petcoke in the energy sector. Some power plants carried out pilot combustion of petroleum coke mixed with coal. These tests, however, have not resulted in a permanent application of petcoke by these power plants. Pilot combustion and studies when petroleum coke was burned in a fluidized bed as CCWS showed the possibility to ensure its stable combustion and good environmental performance. This result matches with global experience aimed at combustion of petcoke in FB boilers, including CFB boilers. In order to study the possibility to introduce the technology of combustion of petcoke as a cavitation coal-water slurry (CCWS) in the furnace of utility oil-and-gas-fired boiler Е-500-140ГМН (ТГМЕ-464), there were computational and analytical studies carried out and boiler modification design developed in one of the Russian power plants. The application of fluidized bed technology allows involving in the balance 750-850 thousand t/year of petroleum coke for modification of 3 boilers.
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