Background technology
Semicoke is commonly called as blue charcoal, has very short blue flame to gain the name when burning because of it, and it is the solid product that the bituminous coal of mud coal, brown coal and high volatile obtains through low temperature (500~700 ℃) destructive distillation.The volatile content height is good high heat value smokeless fuel, can substitute and be better than general coke fully in industries such as iron alloy, calcium carbide, chemical fertilizer, in blast furnace blowing, the fields such as carbonized material and gac that produce bigger development potentiality is arranged simultaneously.
Brown coal are China's one of more coals that distribute, and bury shallow, easy exploitation, and the production of lignite semi-coke can be alleviated the in short supply of bituminous coal, coking coal resource greatly with using, and the Sustainable development of China is had far reaching significance.
Conventional semicoke production technique, its major equipment is the internal thermal upright gas retort, single stove annual production majority of gas retort is at 50,000 tons~100,000 tons, and only can use combination techniques such as a stove is multi-door to realize centralization scale operation.There is following problem in present semicoke production technique:
(1) wasting of resources.The burnt consumption of ton coal, electricity, the water yield are big, and the waste heat in the production process, waste gas utilization rate are low, and the tar rate of recovery is not high, the direct emptying of residual gas and comprehensive utilization.
(2) newly-built semicoke enterprise industrial scale starting point is 600,000 tons/year, all is to carry out design improvement on original vertical heater basis, and the mode that makes up side by side by porous forms scale then, and working time is not long.
(3) the semicoke R﹠D and production falls behind, and Technology is single, and the maximization technical equipment is immature.
Summary of the invention
Purpose of the present invention provides a kind of novel fluidized bed semicoke production system and technology thereof exactly for addressing the above problem, and it produces semicoke by brown coal drying and low-temperature pyrolysis two-stage process.
For achieving the above object, the present invention adopts following technical scheme:
A kind of novel fluidized bed semicoke production system, it comprises dehumidification system and distillation system, and wherein the dehumidification system feed end is connected with feeding unit, and dehumidification system tail gas is through reclaiming behind the dry cleaning apparatus of one-level at least, and dehumidification system is connected with thermal source; Dehumidification system discharge end and dry cleaning apparatus discharge end all are connected with the distillation system feed end; The pyrolysis gas of distillation system is behind one-level cleaning apparatus at least, one tunnel fluidizing medium closed cycle as gas retort, another Lu Zaijing is at least behind the one-level condensing works, a part of emptying, another part burning back is as the native system thermal source, and the distillation system discharge end is connected with the finished product district.
Described feeding unit comprises feed bin, and it is connected with worm conveyor, and worm conveyor is connected with the dehumidification system feed end; Dehumidification system is internal heating fluidized bed drying machine, drying source is from built-in heat exchanger, superheated vapour is as fluidizing medium, flue gas from roasting kiln is connected with built-in heat exchanger, built-in heat exchanger also is connected with smoke induced draught fan I, and the tail gas of superheated vapour and recovery is sent into internal heating fluidized bed drying machine by the bottom.
Described dry cleaning apparatus has two-stage, and the first step is tornado dust collector I, and its discharge end is connected with the distillation system feed end, and the tail gas outlet links to each other with second stage cleaning apparatus electric precipitator, and the fine powder that electric precipitator is collected reclaims.Tail gas after the two-stage dedusting is through recirculation blower I pressurization, and one the road sends internal heating fluidized bed drying machine back to as the fluidizing medium closed cycle; Another road vapor recovery is utilized.
Described distillation system is internal heating fluidized bed gas retort, the destructive distillation thermal source is from built-in heat exchanger, the tail gas that is reclaimed by the destructive distillation cleaning apparatus is as fluidizing medium, flue gas from roasting kiln is connected with built-in heat exchanger, built-in heat exchanger is connected with smoke induced draught fan II, reclaims tail gas and sends internal heating fluidized bed gas retort back to through recirculation blower II.
Described destructive distillation cleaning apparatus comprises tornado dust collector II, and its discharge port is connected with the finished product district, and tail gas is sent into condensing works, and condensing works is a condenser, and the condenser discharge port is got rid of tar and fragrant base polymer, the emptying of a tail gas part, and a part is sent into roasting kiln.
A kind of production technique of novel fluidized bed semicoke production system, its step be,
1) the wet brown coal of water content 30%~50% are delivered in the internal heating fluidized bed drying machine;
2) superheated vapour enters internal heating fluidized bed drying machine, makes an interior material keep stable fluidization; The heat heat drying that brown coal are provided by built-in heat exchanger, by the control residence time of brown coal in bed, be dried to the moisture of requirement after, brown coal are discharged by the fluid bed dryer discharge port, and the dry powder of collecting after cyclone dust removal is delivered to the destructive distillation operation; Drying separates out moisture and partial material is carried by superheated vapour, behind whirlwind and electrostatic precipitation, is recycled blower fan I and takes out and draw, and a part is returned internal heating fluidized bed drying machine as fluidizing medium closed cycle in system, and another part can all be recycled its heat energy; The heat of built-in heat exchanger is provided by the flue gas of roasting kiln, and the flue gas after the heat exchange is extracted emptying out by smoke induced draught fan I;
3) dried material enters the low-temperature pyrolysis operation, the volatile matter that destructive distillation is separated out in internal heating fluidized bed gas retort is after cyclone dust removal, a part is aspirated by recirculation blower II, fluidized wind closed cycle in system as internal heating fluidized bed gas retort, another part is separated out tar and fragrant base polymer through condenser condenses; From the effusive inflammable gas of condenser, emptying behind the part incendivity, the overwhelming majority enters the roasting kiln burning, the flue gas that produces is divided into two-way, one the tunnel enters the thermal source of internal heating fluidized bed drying machine as built-in heat exchanger, and a part enters the thermal source of internal heating fluidized bed gas retort as built-in heat exchanger; Flue gas after the built-in heat exchanger heat exchange of internal heating fluidized bed gas retort is extracted emptying out by smoke induced draught fan II.
Logical 500 ℃ flue gas in the built-in heat exchanger of internal heating fluidized bed gas retort in the described step 3).
Novel fluidized bed semicoke production technique of the present invention can be directly carried out drying, destructive distillation with moisture 30%~50% brown coal, produces semicoke.Dehumidification system is internal heating fluidized bed by feeding unit, superheated vapour, tornado dust collector, electric precipitator, finished product material conveying device, recirculation blower, smoke induced draught fan etc. are formed.Technical process is: moisture 30%~50% wet brown coal, are fallen in the bed to internal heating fluidized bed opening for feed by conveyor delivery.Superheated vapour enters fluidized-bed by internal heating fluidized bed bottom air compartment, through entering bed behind the equal wind of air-distributing device, makes an interior material keep stable fluidization.The heat heat drying that brown coal are provided by built-in heat exchanger in fluidized-bed, by the control residence time of brown coal in bed, after being dried to the moisture of requirement, discharged by the fluid bed dryer discharge port, the dry powder of collecting with tornado dust collector is delivered to the destructive distillation operation.Drying separates out moisture and partial material is carried by the superheated vapour in the bed, behind tornado dust collector dedusting and electrostatic precipitation, is recycled blower fan and takes out and draw, and a part is returned fluidized-bed as drying medium, and another part can all be recycled its heat energy.The heat of built-in heat exchanger is provided by flue gas, and the flue gas after the heat exchange is extracted emptying out by smoke induced draught fan.Dried brown coal enter the low-temperature pyrolysis section, and this section is made up of internal heating fluidized bed gas retort, tornado dust collector, condenser, roasting kiln, recirculation blower, smoke induced draught fan, finished product material handling equipment etc.The volatile matter that destructive distillation is separated out in internal heating fluidized bed gas retort is after dedusting, and a part is by the recirculation blower suction, and as fluidized wind closed cycle in system of fluidized-bed, another part is separated out tar and fragrant base polymer through condenser condenses.From the effusive inflammable gas of condenser, emptying behind a part of incendivity, the overwhelming majority enters the roasting kiln burning, and the flue gas of generation is divided into two-way, and one the tunnel enters the thermal source of dryer section as built-in heat exchanger, and a part enters the thermal source of retort section as built-in heat exchanger.Flue gas after the heat exchange is extracted emptying out by smoke induced draught fan.
The dryer section of this technology can be directly extremely moisture below 5% with moisture 30%~50% brown coal drying with internal heating fluidized bed and superheat steam drying technology grafting.Dry required heat is all provided by built-in heat exchanger, and required fluidisation air quantity is little, and the area of fluidized-bed is little, and floor space is little, a less investment.Under the fluidized state, Dual-Phrase Distribution of Gas olid has the higher gradation of moisture, and can fully contact, the heat transfer efficiency height, and system energy consumption is low.As fluidizing medium, whole drying process is an oxygen-free environment with superheated vapour, does not have the danger of burning and blast, and security of system is reliable.
With the primary device of internal heating fluidized bed gas retort as retort section.Internal heating fluidized bed gas retort is to use as gas retort internal heating fluidized bed, and the required heat major part of destructive distillation is provided by built-in heat exchanger, and logical 500 ℃ flue gas carries out low-temperature pyrolysis with brown coal in the built-in heat exchanger.The volatile matter that destructive distillation is separated out is a part of fluidized wind as fluidized-bed after dedusting.The fluidization destructive distillation has guaranteed the material homogeneous heating, dry distillation efficiency height, the carbon content height of semicoke.The material bed thickness and the residence time all can be adjusted within the specific limits simultaneously, by adjusting the structure and the decoration form of heat exchange element in the drying machine, carbon content and the output that can regulate semicoke, unit throughput is big, turndown ratio is big, and equipment is reliable, and product quality is more stable.
The steam that the dry materials process is separated out, after dedusting, its heat energy that carries can all be recycled, system's energy utilization rate height.
The volatile matter that retort section is separated out can all be recycled.Volatile matter is separated out tar and fragrant base polymer through condenser condenses, can do to be used after the further fine processing.But inflammable gas part emptying burn processing wherein, the overwhelming majority can enter roasting kiln burning, and the flue gas of generation is then respectively as the thermal source of dryer section and retort section built-in heat exchanger, the energy saving of system environmental protection.
After adopting this technology that brown coal are processed upgrading, can produce the solid fuel low temperature semicoke and the derivative coalite tar of good stability, low sulfur-bearing, high heating value.While heat utilization efficiency height, non-environmental-pollution, comprehensive utilization of resources level height, but the continous-stable operation realizes scale operation.
The invention has the beneficial effects as follows: produce semicoke by brown coal drying and low-temperature pyrolysis two-stage process.This system process is simple, flow process short, can realize operate continuously, and energy-saving effect is remarkable, is environmentally friendly, water resources saving type clean coal technological project.
Embodiment
The present invention will be further described below in conjunction with accompanying drawing and embodiment.
Among Fig. 1, it comprises dehumidification system and distillation system, wherein dehumidification system is internal heating fluidized bed drying machine 4, the feed end of internal heating fluidized bed drying machine 4 is connected with feeding unit, feeding unit comprises feed bin 1, it is connected with worm conveyor 2, and worm conveyor 2 is connected with internal heating fluidized bed drying machine 4 feed ends through discharge valve I3.The tail gas of internal heating fluidized bed drying machine 4 reclaims after tornado dust collector I6 and electric precipitator 9 two-stage dedustings.The discharge port of tornado dust collector I6 is sent into internal heating fluidized bed gas retort 12 feed ends through discharge valve III7; Tail gas after the two-stage dedusting is through recirculation blower I8 pressurization, and a part is sent into internal heating fluidized bed drying machine 4 as fluidizing medium, and another part can all reclaim its heat energy.The fine powder that electric precipitator 9 is collected is recyclable.The built-in heat exchanger of internal heating fluidized bed drying machine 4 is connected as thermal source with the flue gas of roasting kiln 19, and built-in heat exchanger is connected with smoke induced draught fan I10, with the flue gas emptying after the heat exchange.The discharge end of internal heating fluidized bed drying machine 4 is connected with the internal heating fluidized bed gas retort 12 of distillation system through discharge valve II5.
The feed end of internal heating fluidized bed gas retort 12 is provided with discharge valve IV11, and its tail gas is divided into two-way after tornado dust collector II14 dedusting, and one the tunnel sends into condenser 16 condensations, and the recirculation blower II17 of leading up to sends internal heating fluidized bed gas retort 12 back to as thermal source.The tail gas part emptying of condenser 16, another part is sent roasting kiln 19 back to.The flue gas of roasting kiln 19 is sent into the built-in heat exchanger of internal heating fluidized bed gas retort 12 as thermal source, and the flue gas after the heat exchange is through smoke induced draught fan II18 emptying.Internal heating fluidized bed gas retort 12 discharge ends are provided with discharge valve V13, and material is sent into the finished product district through discharge valve V13, and the discharge port of tornado dust collector II14 is provided with discharge valve IV15 simultaneously, and the material of its collection is also sent into the finished product district.
Technological process of the present invention is:
The wet brown coal of moisture 30%-50% are fallen in the bed by the opening for feed that worm conveyor 2, discharge valve I3 are delivered to internal heating fluidized bed drying machine 4.Superheated vapour enters fluidized-bed by internal heating fluidized bed drying machine 4 bottom air compartments, through entering bed behind the equal wind of air-distributing device.The superheated vapour that enters bed in this process is controlled effectively, thereby makes an interior material keep stable fluidization.The heat heat drying that brown coal are provided by built-in heat exchanger in fluidized-bed, by the control residence time of brown coal in bed, after being dried to the moisture of requirement, discharge port discharge valve II5 by internal heating fluidized bed drying machine discharges, and moisture 5% of discharge valve III7 collection dry powder is delivered to retort section under tornado dust collector I6.Drying separates out moisture and partial material is carried by the superheated vapour in the bed, flow out internal heating fluidized bed drying machine 4, after tornado dust collector I6 and electric precipitator 9 two-stage dedustings, pressurize by recirculation blower I8, a part is sent into the air compartment of internal heating fluidized bed drying machine 4, as fluidizing medium, recyclable its heat energy of another part.The thermal source of built-in heat exchanger is the flue gas of roasting kiln 19, and the flue tail gas after the heat exchange is extracted emptying out by smoke induced draught fan I10.
The technical process of retort section is: moisture 5% dried brown coal are fallen in the stove by the opening for feed discharge valve IV11 of internal heating fluidized bed gas retort 12, by the heat low-temperature pyrolysis that built-in heat exchanger provides, separate out volatile matter after, obtain the semicoke product.The volatile matter that contains compositions such as coalite tar and coal gas is after tornado dust collector II14 dedusting, and a part is pumped in system's internal recycle by recirculation blower II17 and flows as fluidizing medium.This part fluidizing medium enters internal heating fluidized bed gas retort 12 by the bottom air compartment, through entering bed behind the equal wind of air-distributing device.The fluidizing medium that enters bed in this process is controlled effectively, thereby makes an interior material keep certain fluidization.Another part is separated out tar and fragrant base polymer through condenser 16 condensations.From condenser 16 effusive inflammable gass, emptying behind the part incendivity, the overwhelming majority enters roasting kiln 19 burnings, the flue gas that produces is divided into two-way, one the tunnel enters the thermal source of dryer section as internal heating fluidized bed drying machine 4 built-in heat exchangers, and a part enters the thermal source of retort section as internal heating fluidized bed gas retort 12 built-in heat exchangers.Flue gas after the heat exchange is extracted emptying out by smoke induced draught fan I10, smoke induced draught fan II18 respectively.Semicoke product after the destructive distillation is discharged by internal heating fluidized bed gas retort 12 bottom discharge valve V13 and tornado dust collector II14 bottom discharge valve IV15.