CN101149144A - Circulating fluidized bed incineration system using wet oil shale semi-coke as fuel - Google Patents

Abstract

Translated fromChinese

本发明涉及一种以湿油页岩半焦为燃料的循环流化床焚烧系统，在循环流化床锅炉尾部烟道末端串连两级半焦干燥器，利用循环流化床锅炉尾部烟气和底灰所携带的热量干燥油页岩干馏装置中排出的湿油页岩半焦，产生的干半焦经破碎、筛分后由给料机送入循环流化床锅炉内燃烧，产生的高温烟气加热循环流化床锅炉内的受热面，产生高温、高压水蒸气进入汽轮机－发电机系统发电、供热。循环流化床底灰经冷却后与飞灰一并送入灰仓内，作为建材储备。本发明为高灰、低热值、高含水量的湿油页岩半焦或类似燃料提供了一条高效、洁净的利用途径。

The invention relates to a circulating fluidized bed incineration system using wet oil shale semi-coke as fuel. A two-stage semi-coke dryer is connected in series at the end of the flue at the tail of the circulating fluidized bed boiler, and the flue gas at the tail of the circulating fluidized bed boiler is used The heat carried by the bottom ash dries the wet oil shale semi-coke discharged from the oil shale carbonization device, and the dry semi-coke produced is sent to the circulating fluidized bed boiler by the feeder for combustion after crushing and screening. The high-temperature flue gas heats the heating surface of the circulating fluidized bed boiler to generate high-temperature and high-pressure steam that enters the turbine-generator system for power generation and heat supply. The circulating fluidized bed bottom ash is sent to the ash bin together with the fly ash after cooling, and is used as a building material reserve. The invention provides an efficient and clean utilization path for wet oil shale semi-coke or similar fuels with high ash, low calorific value and high water content.

Description

With the wet oil shale semicockes is the recirculating fluidized bed CIU of fuel

Technical field

The present invention relates to a kind of recirculating fluidized bed CIU, relating in particular to a kind of wet oil shale semicockes with high ash, low heat value, high-moisture is the recirculating fluidized bed CIU of fuel, realize efficient, the clean combustion utilization of oil shale semi-coke, belong to technical field of fuel combustion.

Background technology

Oil shale is a kind of important potential energy source, and reserves are huge, and its reserves are converted to that caloric value is only second to coal and second of row in fossil fuel.If it is converted to shale oil, the reserves of shale oil are about 4,750 hundred million tons in the world, are equivalent to world's natural crude oil in 1997 and verify 5.4 times of recoverable reserves.The traditional approach of oil shale development and use mainly comprises oil refining (Chinese shale oil industry, petroleum industry publishing house, 1984) and at grate furnace, chamber burner internal combustion heat release (Soviet Union's fuel oil shale station boiler, the electric comment in east, nineteen ninety, the 1st phase, 44～51 pages) two approach.Operation result shows for many years, these two single oil shales utilize mode because have that fuel availability is low, some problems such as environmental pollution, combustion technology are immature and can't effectively being promoted.In view of China's " energy medium-term and long-term development planning outline " and current crude oil, electric power and building supplies intense situation day by day, Chinese invention patent " oil shale comprehensive utilization method " (ZL200510024417.2) and Chinese invention patent " the combined gas, heating, cooling and electricity system application system of oil shale " (ZL200510025253.5), successively proposed oil shale comprehensive utilization new departure from different perspectives: oil shale is at first handled through destructive distillation and is produced shale oil and combustion gas; The oil shale semi-coke waste material that destructive distillation generates with send into the recirculating fluidized bed internal combustion, traditional steam turbine-generator system heat supply, the generating of steam introducing of generation after the thin slag of oil shale mixes by a certain percentage; The shale ashes that recirculating fluidized bed is discharged are used as the raw material of industries such as building, chemical industry after treatment.This method of comprehensive utilization will provide efficient, a clean approach that utilizes for the huge oil shale resources of reserves.

Oil shale semi-coke is the solid waste that the destructive distillation stage produces in the above-mentioned oil shale comprehensive utilization scheme, volatile matter content is low, ash content is high, calorific value is low, be subjected to distillation process condition effect water content higher, these characteristics make it be difficult to burning utilization in the burner of routine, though can be used as the fuel of CFBB, but high water content is very big to boiler thermal output influence, need take effective measures to send into the stove internal combustion again after removing the inner most of moisture of semicoke earlier.There is not correlation technique openly to report at present as yet.

Summary of the invention

The objective of the invention is at the deficiencies in the prior art, at existing " oil shale comprehensive utilization method " (Chinese invention patent, ZL 200510024417.2) and " the combined gas, heating, cooling and electricity system application system of oil shale " (Chinese invention patent, ZL 200510025253.5) on the basis of two patents, a kind of recirculating fluidized bed CIU that is suitable for the wet oil shale semicockes burning of high ash, low heat value, high-moisture is proposed, realize efficient, the clean utilization of oil shale semi-coke, guarantee the enforcement of oil shale comprehensive utilization scheme.

For realizing this purpose, in recirculating fluidized bed CIU of the present invention, the wet oil shale semicockes enter first successively, secondary semicoke drier, under the effect of smoke evacuation of CFBB afterbody and hot-air, be dried to water content less than 10%, send into the CFBB internal combustion then, heat release, the high temperature that produces, high-pressure water vapor enters acting generating in traditional steam turbine-generator system, after entering the bottom ash cooler from boiler bottom, the heat ash that the boiler internal combustion generates carries out heat exchange with air, the hot-air that produces is sent into second level semicoke drier, the cooling ash is then sent in the grey storehouse in the lump with the flying dust that deduster is caught, as the building materials deposit, thereby realized the efficient of oil shale semi-coke, clean utilization.

The composition of native system and type of attachment are: the outlet of first order semicoke drier semicoke is connected with second level semicoke drier semicoke inlet, second level semicoke drier semicoke outlet is connected with the screen mill inlet, the screen mill outlet is connected with the feed bin inlet, bin outlet is connected with the batcher inlet, the batcher outlet is connected with the circulating fluidized bed boiler fuel inlet, the ash outlet of CFBB bottom is connected with bottom ash cooler heat ash inlet, the CFBB steam (vapor) outlet is connected with steam turbine-generator system steam inlet, the outlet of CFBB back-end ductwork is connected with first order semicoke drier gas side entrance, first order semicoke drier gas side outlet is connected with the deduster inlet, the deduster exhanst gas outlet is connected with the chimney inlet, and the outlet of deduster flying dust is connected with grey storehouse inlet; The outlet of bottom ash heat exchanger cooling ash is connected with grey storehouse inlet, and bottom ash exchanger heat air outlet slit is connected with second level semicoke drier air intake, and second level semicoke drier air outlet slit is connected with the coal spread wind mouth with the CFBB overfiren air port.

This system works principle is: CFBB tail flue gas temperature is bigger between 130～150 ℃ and flow, carries out heat exchange with wet semicoke after entering first order semicoke drier, the inner most of moisture of the semicoke that wets can be taken away; 800～950 ℃ of CFBB bottom ash temperature enter bottom ash cooler and air and carry out heat exchange, and heated air enters second level semicoke drier, and semicoke further is dried to water content less than 10%; Dried semicoke through the screen mill fragmentation, the screening after granularity less than 10mm, be stored in the feed bin, send into the boiler hearth of circulating fluidized bed internal combustion by batcher, 800～950 ℃ of fire box temperatures, heating surface in the high-temperature flue gas heat cycles fluidized-bed combustion boiler that produces, produce high temperature, high-pressure steam enters steam turbine-generator system generating, heat supply, CFBB tail flue gas flow through successively first order semicoke drier, deduster enter atmosphere from chimney; The cold grey temperature that the bottom ash cooler is discharged is not higher than 200 ℃, sends in the lump in the grey storehouse with the flying dust that deduster is caught, as the building materials deposit.

Advantage of the present invention is: (1) has realized the burning utilization of the wet oil shale semicockes of high ash, low heat value, high-moisture, and the scientific utilization resource has high economy, society and environmental benefit; (2) utilize the waste heat of recirculating fluidized bed tail flue gas and bottom ash to carry heated drying wet oil shale semicockes, realized the Waste Heat Recovery utilization, improved the efficient of oil shale utilization system; (3) adopt the direct combusting oil shale semicoke of Combustion technology of circulating fluidized, the efficiency of combustion height, and belong to low-temperature burning, can effectively control NO_XAnd SO₂Generation and discharging, help keeping the activity of lime-ash simultaneously; (4) native system promptly is applicable to oil shale comprehensive utilization scheme, also utilizes approach for other similar fuel provide a mummification-burning integral, has certain engineering using value.

Description of drawings

Fig. 1 is a system architecture schematic diagram of the present invention.

Among Fig. 1,1 is that CFBB, 2 is that steam turbine-generator system, 3 is that feed bin, 4 is that screen mill, 5 is that batcher, 6 is that second level semicoke heat exchanger, 7 is that bottom ash cooler, 8 is that grey storehouse, 9 is that first order semicoke heat exchanger, 10 is that deduster, 11 is that chimney, 12 is that overfiren air port, 13 is the coal spread wind mouth.

The specific embodiment

Below in conjunction with accompanying drawing technical scheme of the present invention is further described.

As shown in Figure 1, system of the present invention type of attachment is: the outlet of first order semicoke drier 9 semicokes is connected with second level semicoke drier 6 semicokes inlet, second level semicoke drier 6 semicokes outlet is connected with screen mill 4 inlets, screen mill 4 outlets are connected with feed bin 3 inlets, feed bin 3 outlets are connected with batcher 5 inlets, batcher 5 outlets are connected with CFBB 1 fuel inlet, the ash outlet of CFBB 1 bottom is connected with bottom ash cooler 7 heat ash inlets, CFBB 1 steam (vapor) outlet is connected with steam turbine-generator system 2 steam inlets, the outlet of CFBB 1 back-end ductwork is connected with first order semicoke drier 9 gas side entrances, first order semicoke drier 9 gas side outlets are connected with deduster 10 inlets, deduster 10 exhanst gas outlets are connected with chimney 11 inlets, and the outlet of deduster 10 flying dusts is connected with grey storehouse 8 inlets; The 7 cooling ash outlets of bottom ash heat exchanger are connected with grey storehouse 8 inlets, bottom ash heat exchanger 7 hot air outlets are connected with second level semicoke drier 6 air intakes, and second level semicoke drier 6 air outlet slits are connected with coal spread wind mouth 13 with the overfiren air port 12 of CFBB 1.

The native system operation principle is: CFBB 1 tail flue gas temperature is bigger between 130～150 ℃ and flow, enters first order semicoke drier 9 backs and carries out heat exchange with wet semicoke, the inner most of moisture of the semicoke that wets can be taken away; 800～950 ℃ of CFBB 1 bottom ash temperature enter bottom ash cooler 7 and carry out heat exchange with air, and heated air enters second level semicoke drier 6, and semicoke further is dried to water content less than 10%; Dried semicoke through screen mill 4 fragmentations, the screening after granularity less than 10mm, be stored in the feed bin 3, send into CFBB 1 burner hearth internal combustion by batcher 5,800～950 ℃ of fire box temperatures, heating surface in the high-temperature flue gas heat cycles fluidized-bed combustion boiler 1 that produces, produce high temperature, high-pressure steam enters 2 generatings of steam turbine-generator system, heat supply, CFBB 1 tail flue gas flow through successively first order semicoke drier 9, deduster 10 enter atmosphere from chimney 11; The cold grey temperature that bottom ash cooler 7 is discharged is not higher than 200 ℃, sends in the lump in the grey storehouse 8, as the building materials deposit with the flying dust that deduster 10 is caught.

Claims (1)

1. one kind is the recirculating fluidized bed CIU of fuel with the wet oil shale semicockes, it is characterized in that: the semicoke outlet of first order semicoke drier (9) is connected with the semicoke inlet of second level semicoke drier (6), the semicoke outlet of second level semicoke drier (6) is connected with screen mill (4) inlet, screen mill (4) outlet is connected with feed bin (3) inlet, feed bin (3) outlet is connected with batcher (5) inlet, batcher (5) outlet is connected with CFBB (1) fuel inlet, the ash outlet of CFBB (1) bottom is connected with bottom ash cooler (7) heat ash inlet, CFBB (1) steam (vapor) outlet is connected with the steam inlet of steam turbine-generator system (2), the outlet of CFBB (1) back-end ductwork is connected with the gas side entrance of first order semicoke drier (9), the gas side outlet of first order semicoke drier (9) is connected with deduster (10) inlet, the exhanst gas outlet of deduster (10) is connected with chimney (11) inlet, and the flying dust outlet of deduster (10) is connected with grey storehouse (8) inlet; The outlet of bottom ash heat exchanger (7) cooling ash is connected with grey storehouse (8) inlet, the hot air outlet of bottom ash heat exchanger (7) is connected with the air intake of second level semicoke drier (6), and the air outlet slit of second level semicoke drier (6) is connected with coal spread wind mouth (13) with the overfiren air port (12) of CFBB (1).