Combined system of oil shale bubble column dry distillation and semicoke circulating fluidized bed combustion

Abstract

The invention relates to a combined system of oil shale bubble column dry distillation and semicoke circulating fluidized bed combustion; a bubble column is used as an oil shale dry distillation furnace; a circulating fluidized bed is used as a semicoke combustion utilization device; both hot ash and generated by combustion of the circulating fluidized bed and circulating hot gas are used as a heat carrier of the dry distillation furnace; oil shale particles are heated and decomposed in the bubble column; the generated gaseous substance is separated into gas, shale oil, water and oily sludge through a gas-liquid separator, and a oil-water separator; semicoke discharged from the bottom of the bubble column is directly delivered into the circulating fluidized bed for combustion; the generated high-temperature flue gas is mixed with the high-temperature flue gas discharged from a gas combustor, and then is introduced into a gas-solid separator; the separated fly ash is delivered respectively to the bubble column, a material-returning valve, and an external gas-solid heat exchanger; the flue gas after dedusting passes through a tail heating surface, and finally is discharged into atmosphere; steam generated by the tail heating surface is used for power generation and heat supply. Compared with the prior art, the invention can increase the quality of shale oil and gas, and can effectively reduce the energy loss and environment pollution of the system.

Description

technical field [0001] The invention belongs to the technical field of oil shale resource utilization, and relates to a combination system of oil shale dry distillation and semi-coke combustion, in particular to a system using a bubbling bed as an oil shale dry distillation furnace and a circulating fluidized bed as a semi-coke combustion utilization The device, the hot ash generated by the combustion of the circulating fluidized bed and the circulating hot gas are used as the heat carrier of the retort furnace for the oil shale combined utilization system, which is used for oil refining, gas production and heat supply, etc., to realize the comprehensive utilization of oil shale. Background technique [0002] Oil shale is a solid combustible organic mineral body with high ash content and low calorific value. Low temperature dry distillation can obtain shale oil similar to natural petroleum. Among fossil fuels, its reserves are converted into calorific value and rank second o...

AI Technical Summary

Problems solved by technology

At present, China's oil shale dry distillation technology is mainly based on Fushun furnace, because it uses the heat generated by burning semi-coke and non-condensable gas to dry oil shale, resulting in low shale oil yield and poor gas quality, which seriously restricts The popularization and large-scale development of this technology; the bottom of the carbonization furnace is sealed with water and the semi-coke is cooled by water, so that the semi-coke with a certain calorific value cannot be sent into the circulating fluidized bed for further utilization due to its high water content, resulting in Waste of resources and pollution of water resources; affected by particle distribution characteristics, temperature distribution and resistance characteristics inside the retort furnace, oil shale with small particles smaller than 12mm cannot be retorted and treated as tailings, resulting in about 20% of shale oil waste of resources

However, foreign oil shale utilization technologies cannot achieve efficient, clean and comprehensive utilization of oil shale due to the shortcomings of complex equipment, low resource utilization, single product form, or poor oil quality.

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