Integral process for oil shale retorting oil refining and coal-char combustion power generation

Abstract

The present invention discloses an oil shale carbonization oil refining, carbocoal burning electricity generating integrated technology. The present invention is characterized in that green ore oil shale is crushed into 0 to 15mm grains by a crusher, through that circulating fluid bed boiler circulating ash is used as a solid heat carrier, the mixture of the oil shale and the circulating ash is fed into a roller retort to form oil shale oil refining, carbocoal and the oil shale are mixed, fluidized and burned to generate electricity as a whole, separated non-condensation carbonization coal gas is fed into the circulating fluid bed boiler and the both are burned with the carbocoal and the oil shale together or is fed into a gas engine for direct-fired power generation; the carbon content of the clinker after burned on the circulating fluid bed is less than 2 percent, thus no further roasting is necessary, and the present invention can be directly used as building raw material; the thermal value of produced carbonization coal gas which can be directly used as fuel to feed into the boiler for burning is high, the quantity of heat released through burning can be transferred to the water through the heated surface of the boiler, the water is heated into a overheat steam to be used as out-supplied working substance and / or to be fed into a steam turbine for power and electricity generating. The present invention has the advantages that the comprehensive utilization degree is high, the cost is low, the technology is scientific and reasonable, etc.

Description

technical field [0001] The invention relates to the technical field of comprehensive utilization of oil shale resources, and is an integrated process of oil shale dry distillation, refining, and semi-coke combustion for power generation. The integrated process can also be used for coal and biomass. Background technique [0002] Oil shale is an important energy resource. Using oil shale as an energy source, it can be converted into shale oil and electricity at the same time; it can also be used as a resource to convert ash residue into building materials, and finally achieve no solid waste discharge. The best way to comprehensively utilize shale. [0003] The existing process routes for the development and utilization of oil shale: one is to adopt the process route based on retort furnace for dry distillation and refining; the other is to adopt the process route based on circulating fluidized bed boiler combustion power generation. The disadvantages of the existing carboniz...

AI Technical Summary

Problems solved by technology

The disadvantages of the existing carbonization furnace-based process route for carbonization and refining are: ① Usually, about 20% of the total clastic shale below 8 mm is discarded; ② The refining yield is 63-90%, and 10- 37% of shale oil loss; ③The calorific value of the semi-coke of the solid residue after dry distillation is still 2500-5000kJ / kg, and the heat loss of the solid is large; ④The environmental pollution of slag discharge, waste gas and sewage exceeds the standard

This brings about three major problems: First, due to the use of massive shale, the retort time is quite long, generally 12 to 24 hours, and due to the large size of the particles, many large particles cannot be completely retorted. There are black cores, so the shale carbonization efficiency is low, the oil yield rate is low, and the utilization rate is low; the second is to use hot gas as the heat carrier for carbonization, which requires an external heat source to heat the gas. Usually, a regenerative heating furnace is used, that is, the regenerative heating furnace is first used The gas is burned in the heating furnace to heat the furnace body, and then the cold gas is sent into the heating furnace to transfer the heat of the furnace body to the cold gas. After heating, it is sent to the carbonization furnace to heat the oil shale carbonization, so it not only consumes a lot of gas , a waste of energy, and the temperature of the dry distillation hot gas is always changing, resulting in periodic temperature changes in the dry distillation furnace, unstable oil output, and low oil yield; third, if the semi-coke after carbonization in the vertical cylindrical furnace continues to be used as boiler fuel , must be cooled first and then further crushed to meet the requirements of boiler combustion. If it is a wet desiccator, it must be cooled with water first, then dried, and then crushed. Therefore, the energy consumption is relatively large.

However, the purpose of this type of carbonization furnace is single at present, and an additional combustion furnace is required to burn shale semi-coke into high-temperature shale ash to provide a solid heat carrier, and the remaining semi-coke and ash are discarded in large quantities

Since the combustion furnace is only used to generate solid heat carrier, it cannot achieve the purpose of power generation and heat supply

[0006] The process route based on circulating fluidized bed boilers for combustion power generation and heat supply can achieve higher combustion efficiency and thermal efficiency. Staged combustion reduces the emission of nitrogen oxides, so it is a clean combustion, but the biggest problem with using a circulating fluidized bed boiler to burn oil shale for power generation is that it burns the oil resources in the oil shale

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