Disclosure of Invention
Aiming at the problems, the invention aims to provide a process system for preparing pyrolysis oil gas by using waste tires, which is characterized in that: comprises a vertical pyrolysis tower, a feeding system, a discharging system and a pyrolysis oil gas condenser.
The vertical pyrolysis tower comprises a vertical pyrolysis tower body, a rotary rake roller, an upper bearing seat, a lower bearing seat and a supporting foot, wherein the vertical pyrolysis tower body is provided with a jacket through which high-temperature flue gas at 450-500 ℃ flows, a hollow helical blade is designed in the jacket, the high-temperature flue gas rises spirally along a channel formed by the hollow helical blade, the vertical pyrolysis tower body is uniformly heated, the problem that the high-temperature flue gas cannot flow through dead corners of the vertical pyrolysis tower body to cause bulges is solved, a pyrolysis oil gas outlet is designed at the upper part of the vertical pyrolysis tower body, and the upper bearing seat and the lower bearing seat are arranged at the upper end and the lower end of the vertical pyrolysis tower body to ensure the coaxiality of the central axes of the vertical pyrolysis tower body and the rotary rake roller.
The rotary harrow roller comprises a rotary harrow roller body, an air inlet shaft head and an air outlet shaft head, wherein the air inlet shaft head and the air outlet shaft head are respectively designed at the lower end and the upper end of the rotary harrow roller body, and the rotary harrow roller body, the air inlet shaft head and the air outlet shaft head rotate around the same central shaft.
The utility model discloses a steam-water mixing chamber, including the axle head of admitting air, exhaust spindle head hole, the heat insulation tile, labyrinth cooling groove, bearing position are outwards designed in proper order to 450 ~ 500 ℃ high temperature flue gas, follow the hole, labyrinth cooling groove includes spiral coil, soda mixing chamber, buckled plate, and spiral coil fixes at soda mixing chamber inner wall, and the cooling water gets into the vaporization of soda mixing chamber thermal evaporation from spiral coil, and the bubble striking spiral coil that the boiling produced, buckled plate break rapidly for more tiny bubble to make the bubble evenly distributed in the cooling water, in other words just avoid steam coefficient of heat conductivity to differ greatly to lead to the local overheat of locular wall metal to produce the creep.
The outer surface of the rotary rake roller body is spirally distributed with rake nails, the rake nails in quantity are rotated to apply downward thrust to the rubber block along with the rotary rake roller body by adjusting the included angle between the rake nails and the section of the rotary rake roller body, the rake nails in quantity of ¼ are rotated to apply upward thrust to the rubber block along with the rotary rake roller body, the rake nails apply downward thrust to the rubber block to help the asphalt jelly and the steel wire to be smoothly discharged, the resultant force of the two rake nails forms a twisting and cutting effect on the rubber block, the pyrolytic carbon hard shell is twisted and broken to enable the rubber block to be continuously pyrolyzed, meanwhile, a rubber block accumulation layer is stirred to form a gap, pyrolytic oil gas can escape from the gap of the accumulation layer, the pyrolytic oil gas is in mass transfer and heat transfer with the rubber block in the upward flowing process, and the gas-liquid-solid mass transfer and heat transfer efficiency far exceeds the gas-solid transfer and heat transfer efficiency of the rotary rake roller body and the rubber block.
The cross support frame is installed at both ends in the rotary harrow roller body, and the cross support frame is fixed with helical blade through the hollow shaft, and high temperature flue gas rises along the passageway spiral that helical blade formed, and even heating rotary harrow roller body avoids the unable problem that causes the swell of circulation harrow roller body dead angle of flowing through of high temperature flue gas.
The feeding system comprises a bucket lifting trolley mechanism and a three-section type bell jar feeding mechanism, wherein the bucket lifting trolley mechanism comprises a self-weighing trolley, a lifting track and a pulley traction assembly.
The three-section bell jar feeding mechanism comprises an initial-section bell jar storage bin, a middle-section bell jar storage bin and a tail-section bell jar storage bin, wherein the initial-section bell jar storage bin is provided with an initial-section hopper body, an upper bell jar base, a hanging rod and a pin shaft assembly, the upper bell jar base is arranged at the bottom of the initial-section hopper body, the pin shaft assembly is connected with the upper bell jar through the hanging rod to control the upper bell jar to move up and down, and the upper bell jar is matched with a sealing surface of the upper bell jar base to be tightly adhered to form upper sealing of the middle-section bell jar storage bin; the middle section bell jar storage bin is provided with a middle section hopper body, a middle bell jar base, a sling chain, a rotary ball assembly, an inner and outer partition bin assembly and a tail gas recovery buffer tank, wherein the middle bell jar base is arranged at the bottom of the middle section hopper body, the rotary ball assembly is connected with the middle bell jar through the sling chain to control the middle bell jar to move up and down, a sealing surface of the middle bell jar and the middle bell jar base is matched and tightly adhered to form a lower seal of the middle section bell jar storage bin and an upper seal of the tail section bell jar storage bin, the inner and outer partition bin assembly is arranged at the upper part of the middle section hopper body, inert tail gas is output from the tail gas recovery buffer tank, enters the middle section hopper body through an outer annular air passage of the inner and outer partition bin assembly to be swept, and air in gaps between rubber blocks of the waste tires is extruded and discharged; the tail-section bell jar storage bin is provided with a tail-section hopper body, a lower bell jar seat, a suspension wire, a pull rod assembly and a multi-stage steam ejector assembly, wherein the lower bell jar seat is designed at the bottom of the tail-section hopper body, the pull rod assembly is connected with the lower bell jar through the suspension wire to control the lower bell jar to move up and down, the lower bell jar is matched and tightly attached to a sealing surface of the lower bell jar seat to form a lower seal of the tail-section bell jar storage bin, the multi-stage steam ejector assembly comprises a first-stage ejector, a second-stage ejector, a third-stage ejector, a middle condenser and a last-stage ejector, the first-stage ejector, the second-stage ejector, the third-stage ejector, the middle condenser and the last-stage ejector are sequentially connected, and the vacuum degree of the tail-section bell jar storage bin is controlled to be 1000-1300 Pa through continuous multi-stage pressurization.
The inert tail gas is the exhaust gas which is obtained by recycling high-temperature flue gas output by the pyrolysis gas combustion kiln and exchanging heat through the vertical pyrolysis tower body and the rotary rake roller, and the oxygen content is reduced to be below 3%.
The discharging system comprises a discharging disc body, a water circulation mechanical seal and a ox-head scraper knife discharging assembly.
The method is characterized in that rake nails on the surface of a rotary rake roller apply downward thrust to a rubber block to help the asphalt jelly and a steel wire cluster move downward, the rake nails form a twisting and cutting effect on the rubber block, a pyrolytic carbon hard shell is twisted and broken to enable the rubber block to fully complete a pyrolysis process to form pyrolytic carbon, in order to enable the pyrolytic carbon and the steel wire cluster to smoothly move downward from an annular reaction chamber between the rotary rake roller and a vertical pyrolysis tower body for discharging, a W-shaped discharging tray body is designed to be matched with the annular reaction chamber to bear the pyrolytic carbon and the steel wire cluster, the cross section of the W-shaped discharging tray body is saddle-shaped, the center of the W-shaped discharging tray body is fixedly connected with the rotary rake roller and rotates together, and an annular deep groove is designed on the outer edge of the W-shaped discharging tray body, so that the pyrolytic carbon and the steel wire cluster uniformly fall into the annular deep groove of the discharging tray body from the annular reaction chamber.
The water circulation mechanical seal comprises a water tank, a moving ring friction pair, a static ring friction pair, a spiral spring pressing device and a water-cooling discharge pipe, wherein the moving ring friction pair is designed on the discharge disc body, the static ring friction pair is designed into a wedge shape, and the spiral spring pressing device can provide axial and radial compensation for the wedge-shaped friction ring. Cooling water in the water tank descends through the water-cooling calandria and is injected into the static ring friction pair and the spiral spring pressing device, the static ring friction pair and the spiral spring pressing device are cooled, a pressure water injection channel and a steam exhaust hole are designed in the wedge-shaped friction ring, cooling water pressure is injected into a sealing surface of the friction pair through a water pump, steam generated when the cooling water pressure is lubricated, forms inert gas protection, water-vapor mixture generated when the cooling water injected through the pressure water injection channel is heated is exhausted to the water tank from the steam exhaust hole through the plate gap of the overlapped blade springs, and the water tank, the water-cooling calandria, the static ring friction pair and the plate gap channel form a natural water circulation loop.
The static ring friction pair comprises a wedge-shaped friction ring and an overlapped blade spring, the wedge-shaped friction ring consists of trisection split rings, the overlapped blade spring comprises an inner ring, an outer ring and plates, 40-200 rectangular plates with the same specification are uniformly distributed around the inner ring in an involute-like manner, each plate is provided with a linking hole, two stacked grid plate curtain belts are formed in series through hinges, the trisection of the inner ring is tightly attached to the outer circular wall of the wedge-shaped friction ring, the outer ring and the inner ring concentrically restrain the grid plate curtain belts consisting of the plates in a circular ring between the two plates, the adjacent two plates are sequentially stacked, the tail end of the front plate is used as a fulcrum of the rear plate, the rear plate generates bending deformation around the fulcrum to play a spring role, the elastic deformation direction of each plate points to the circle center, therefore, the overlapped blade spring can adjust the radial compensation amount of the sealed friction pair by changing the width of the plates and the thickness of the tail end of the plates, the radial compensation quantity is close to the value of the tail end thickness of the deduction plate piece at the distance between the inner ring and the outer ring, and the radial compensation with limited working space is facilitated.
Ox head spiller ejection of compact subassembly includes spiller, shaftless helical blade, ox head discharge gate, because ejection of compact disk body concreties and together gyration with gyration rake roll, and pyrolytic carbon and steel wire group are shoveled by the spiller of slope installation, and the shaftless helical blade rotation with spiller parallel arrangement scrapes into ox head discharge gate with pyrolytic carbon and steel wire group, avoids steel wire group to block up ox head discharge gate.
The pyrolysis oil gas condenser comprises a secondary condenser and a water circulation loop.
The secondary condenser comprises a primary tube sheet type condenser, a secondary tube sheet type condenser, a cyclone separator, a reflux device and a U-shaped liquid seal return pipe, tube bundles in a tube box of the primary tube sheet type condenser and the secondary tube sheet type condenser are also ascending pipes of a water circulation loop, pyrolysis oil gas flows along the primary tube sheet type condenser and the secondary tube sheet type condenser from bottom to top, the primary tube sheet type condenser comprises a primary tube pass upper connecting pipe, a primary shell pass lower connecting pipe, a primary tube pass lower connecting pipe, a liquid distribution disc and a primary condensate outlet, the secondary tube sheet type condenser comprises a secondary tube pass upper connecting pipe, a secondary shell pass lower connecting pipe, a secondary condensate outlet, oil gas pyrolysis sequentially flows from the primary shell pass lower connecting pipe, the primary shell pass upper connecting pipe, the secondary shell pass lower connecting pipe and the secondary shell upper connecting pipe, is condensed and enters the cyclone separator, in order to prevent the flow of pyrolysis gas, a weir plate is designed at the outlet of the primary condensate, a U-shaped liquid seal is designed at the bottom of the cyclone separator, pyrolysis oil separated by primary condensation is collected to the outlet of the primary condensate, pyrolysis oil separated by secondary condensation and pyrolysis oil separated by cyclone are all collected to the reflux device and then are conveyed to a liquid distribution disc through a U-shaped liquid seal reflux pipe, the liquid distribution disc comprises a gas distribution plate and a liquid distribution cover plate, nozzles on the gas distribution plate correspond to air holes of the liquid distribution cover plate one by one, the liquid distribution disc covers an inlet of a lower connecting pipe of a primary shell pass, pyrolysis gas is sprayed out from the nozzles on the gas distribution plate, and the pyrolysis oil reflux liquid is injected to mix and transfer heat when flowing out through the air holes of the liquid distribution cover plate.
The water circulation loop comprises a drum, a header, a downcomer and an ascending pipe, cooling water is infused from the header, a steam and water mixture is generated by the pyrolysis oil gas heat exchange of the ascending pipe and the shell pass through the primary pipe pass lower connecting pipe and the secondary pipe pass lower connecting pipe, then the steam and the water are separated by the drum through the primary pipe pass upper connecting pipe and the secondary pipe pass upper connecting pipe, the water returns to the header from the downcomer, and the working steam is produced for standby while the natural circulation of the water is completed.
The inventor finds that the tire consists of an outer tire, an inner tire and a cushion belt, the outer tire consists of three main parts, namely a tire body, a tire tread and a tire bead, the tire body is formed by attaching a plurality of layers of rubberized cord fabrics according to a certain angle, and the cord fabrics are usually made of high-strength steel wires and synthetic fiber rubberized fabrics; the tread contacts with the ground and is made of heat-resistant and shear-resistant rubber materials; the tyre bead is used for tightly fixing the tyre on a wheel rim, and mainly comprises a steel wire ring, triangular filling rubber and steel wire ring wrapping cloth. The pneumatic tire can be classified into a car tire, a truck tire, an agricultural tire, an engineering tire, a special vehicle tire, an aircraft tire, a motorcycle tire and a bicycle tire according to the application of the pneumatic tire, and the recycled waste tire is generally a car tire, a truck tire, an agricultural tire, a motorcycle tire and a bicycle tire, and the structure of the waste tire is generally an oblique tire and a radial tire. The recovered waste tires are used for building fillers, highway fillers, regenerated rubber preparation, fuel oil and carbon black preparation by pyrolysis and the like.
The inventor finds that the process for preparing fuel oil and carbon black by pyrolyzing waste tires requires the processes to be carried out in a vacuum, inert gas protection and anaerobic closed environment, and the process is currently put into industrial production methods such as reaction kettle pyrolysis, rotary reaction furnace pyrolysis, vertical tower pyrolysis and the like. Although the pyrolysis method of the reaction kettle has the advantage that the whole material is fed without being crushed, the pyrolysis method has high energy consumption and low finished product yield and is difficult to popularize due to the reason that continuous production cannot be realized; the rotary reaction furnace pyrolysis method is difficult to popularize due to the reasons that feeding and discharging are difficult, pollutants are easy to leak through high-temperature dynamic sealing and the like; the vertical tower pyrolysis method has the advantages from the thermodynamic point of view undoubtedly compared with the first two methods, the power of the material from top to bottom is provided by gravity, the hot air completes heat exchange with the material from bottom to top, the feeding and discharging and the heat exchange are easy to implement, the vertical tower is static equipment, and the high-temperature sealing problem is easy to solve, but the technical problem that a discharge channel is blocked by a rubber jelly and a steel wire ball which are reformed after long chain breakage of rubber exists in the pyrolysis process of the waste tires, the surface of the waste tires is further pyrolyzed to generate pyrolytic carbon crust and the interior of the waste tires is prevented from being pyrolyzed continuously, and the technical problem that the pyrolysis efficiency is low due to the low thermal conductivity of the waste tires is solved.
The inventor finds that the waste tires are pyrolyzed to recover pyrolysis oil and pyrolytic carbon as main purposes to further prepare the pyrolysis oil and the pyrolytic carbonThe pyrolysis gas is uneconomical if being used as a main product, because the yield of the pyrolysis gas is improved and a higher pyrolysis temperature (550-600 ℃) is needed to break the pyrolysis oil chain hydrocarbon with a higher molecular weight to generate the pyrolysis gas mainly containing methane, ethane, ethylene, propylene and other components with a smaller molecular weight, a part of energy is wasted on damaging the molecular chain due to the higher pyrolysis temperature, and the pyrolysis gas generated by degrading the pyrolysis oil is flammable and explosive and is not easy to store and transport; in order to reduce the manufacturing cost of the pyrolysis reaction furnace and meet the requirements of mechanical processing, Q345R steel is selected as a furnace body material, the allowable stress requirement of the Q345R steel at high temperature is considered, namely the steel is used at the temperature of not more than 475 ℃, the comprehensive consideration of the factors is taken, the pyrolysis process temperature of the waste tires is designed to be 350-400 ℃, the heat source for pyrolyzing the waste tires is high-temperature flue gas generated by recycling pyrolysis gas, the pyrolysis gas is non-condensable combustible gas after pyrolysis oil is condensed at normal temperature, and the low-grade heat value is 17-54 MJ/Nm3. Due to the requirements of heat transfer efficiency and heat transfer temperature difference, the temperature of flue gas from the outlet of the waste tire pyrolysis gas combustion kiln to the jacket of the vertical pyrolysis tower body and the inlet of the rotary rake roller is controlled to be 550-560 ℃, the temperature of flue gas after heat exchange of the vertical pyrolysis tower body and the rotary rake roller is 410-420 ℃, and the average temperature difference of heat transfer is 140 ℃, so that the pyrolysis gas combustion kiln can regulate and control the temperature of high-temperature flue gas generated by pyrolysis gas combustion, a cold source is required to be introduced to be mixed with the high-temperature flue gas, and the temperature required by a pyrolysis process is achieved by regulating the component ratio of the waste tire pyrolysis gas combustion kiln to the jacket of the vertical pyrolysis tower body and the rotary rake roller.
The inventor finds that in the waste tire pyrolysis process, the requirements of material balance, water (steam) balance and energy balance and the total targets of saving energy, reducing emission and recycling, the oxygen content of the exhaust gas after the high-temperature flue gas output by the pyrolysis gas combustion kiln is subjected to heat exchange through the vertical pyrolysis tower body and the rotary rake roller is reduced to be less than 3%, the temperature is 410-420 ℃, the pressure bearing of the rotary rake roller under the dynamic seal high-temperature working condition is limited, and the designed absolute pressure is not more than 105kPa, so that the pressure index of the exhaust gas is lower than the pressure requirements of a secondary air inlet of a combustor and a cold source at an inlet of the pyrolysis gas combustion kiln of 112-118 kPa, and the exhaust gas cannot be directly recycled. According to the operating principle of turbocharging, considering that the pressure of the discharged waste gas is low, selecting an axial air inlet and vertical upward exhaust mode with small pressure loss at the air inlet end, and using a cantilever type rotor structure, the discharged waste gas is expanded through a static blade grid and a movable blade wheel to do work, the heat energy is converted into mechanical energy for rotating the movable blade wheel, the movable blade wheel drives a planetary speed increaser to drive the air turbine, the air turbine pumps the air to pressurize and enter a combustor, a blower required by premixed air conveyed by the combustor is replaced, but the absolute pressure of an inlet of the discharged waste gas is 105kPa, an outlet of the discharged waste gas is directly communicated with a chimney, namely, the backpressure of a waste gas turbine is 101 kPa, the pressure difference of the inlet and the outlet is not enough to overcome the pressure loss of a flow passage of the static blade grid and the movable blade wheel to cause the rotation stop of the movable blade wheel, so that a set of a steam jet pump is required to jet the discharged waste gas through high-pressure steam, the outlet pressure of the discharged waste gas is reduced to 50-55 kPa, the pressure difference between the inlet and the outlet of the waste gas turbine reaches 52-57 kPa, and the movable impeller can work reliably. The steam source of the steam jet pump is saturated steam generated by condensation of pyrolysis oil, the pressure is 0.35-0.4 MPa, the exhaust gas and steam mixed gas at the outlet of the steam jet pump are sent to an expansion tank, non-condensable gas in the expansion tank is inert tail gas, the inert tail gas has three purposes, one of the inert tail gas serves as a cold source for adjusting the temperature of the pyrolysis gas combustion kiln, the other inert tail gas serves as an air source for adjusting the coefficient of excess air of a pyrolysis gas combustor, and the third inert tail gas serves as inert protective gas required by purging of a middle-section bell jar storage bin.
The inventor finds that the temperature of pyrolysis oil produced by a waste tire pyrolysis reaction furnace is 350-400 ℃, the pyrolysis oil needs to be condensed and fractionated and then is utilized, the condensation is generally realized through a dividing wall type heat exchanger, a cold source generally selects cooling water, the cooling water absorbs heat energy and converts the heat energy into steam, the steam with different qualities generated by multistage condensation is utilized, the steam can be used as a working fluid source with different pressure levels in a multistage steam ejector (pump) and can also be used as cooling steam of an exhaust turbine, and the total targets of material balance, water (steam) balance and energy balance in the waste tire pyrolysis process are achieved, and the total targets of energy conservation, emission reduction and cyclic utilization are achieved.
The inventor finds, to above-mentioned technological problem, this application has designed gyration harrow roller, gyration harrow roller includes gyration harrow roll body, the axle head that admits air, exhaust axle head, and the axle head that admits air designs respectively at the lower extreme and the upper end of gyration harrow roll body with the exhaust axle head, and gyration harrow roll body, the axle head that admits air, exhaust axle head revolve around same center pin. The utility model discloses a steam-water mixing chamber, including the axle head of admitting air, exhaust spindle head hole, the heat insulation tile, labyrinth cooling groove, bearing position are outwards designed in proper order to 450 ~ 500 ℃ high temperature flue gas, follow the hole, labyrinth cooling groove includes spiral coil, soda mixing chamber, buckled plate, and spiral coil fixes at soda mixing chamber inner wall, and the cooling water gets into the vaporization of soda mixing chamber thermal evaporation from spiral coil, and the bubble striking spiral coil that the boiling produced, buckled plate break rapidly for more tiny bubble to make the bubble evenly distributed in the cooling water, in other words just avoid steam coefficient of heat conductivity to differ greatly to lead to the local overheat of locular wall metal to produce the creep. The outer surface of the rotary rake roller body is spirally distributed with rake nails, the rake nails in quantity are rotated to apply downward thrust to the rubber block along with the rotary rake roller body by adjusting the included angle between the rake nails and the section of the rotary rake roller body, the rake nails in quantity of ¼ are rotated to apply upward thrust to the rubber block along with the rotary rake roller body, the rake nails apply downward thrust to the rubber block to help the asphalt jelly and the steel wire to be smoothly discharged, the resultant force of the two rake nails forms a twisting and cutting effect on the rubber block, the pyrolytic carbon hard shell is twisted and broken to enable the rubber block to be continuously pyrolyzed, meanwhile, a rubber block accumulation layer is stirred to form a gap, pyrolytic oil gas can escape from the gap of the accumulation layer, the pyrolytic oil gas is in mass transfer and heat transfer with the rubber block in the upward flowing process, and the gas-liquid-solid mass transfer and heat transfer efficiency far exceeds the gas-solid transfer and heat transfer efficiency of the rotary rake roller body and the rubber block. The cross support frame is installed at both ends in the rotary harrow roller body, and the cross support frame is fixed with helical blade through the hollow shaft, and high temperature flue gas rises along the passageway spiral that helical blade formed, and even heating rotary harrow roller body avoids the unable problem that causes the swell of circulation harrow roller body dead angle of flowing through of high temperature flue gas.
The inventor finds that the rotary rake roller body, the air inlet shaft head and the air outlet shaft head are all made of Q345R steel, and the rotary rake roller body, the air inlet shaft head and the air outlet shaft head respectively achieve the level II welding seam standard after being made; the spiral blades are welded and fixed on the pipe shaft, the whole body and the cross-shaped support frame are assembled and sent into the rotary rake roller body to be rolled into the barrel body, in order to prevent the barrel body from being locally deformed due to welding, the cross-shaped support frame is fixed in the rotary rake roller body by adopting spot welding positioning and back section welding, and finally, the two ends of the rotary rake roller body are blocked by using end sockets; the air inlet shaft head and the air exhaust shaft head are coiled into the barrel, the heat insulation tile is embedded in the barrel, the spiral coil pipe is fixed outside the barrel, then an outer cover plate of the steam-water mixing chamber is welded, a water pressure test is carried out after the corrugated plates are installed, and the labyrinth cooling tank is guaranteed to have no leakage under the pressure of 1.0 MPa. Connecting the air inlet shaft head and the air exhaust shaft head with the rotary harrow roller body, tempering, and then using the cylinder body of the rotary harrow roller body as a processing reference, and lathing the bearing positions of the air inlet shaft head and the air exhaust shaft head by using a floor lathe so as to ensure the coaxiality of the rotary harrow roller body, the air inlet shaft head and the air exhaust shaft head; and finally, fixing the braks on the outer surface of the rotary harrow roller body one by one, wherein the braks are arranged on the outer surface of the rotary harrow roller body according to the spiral line-like arrangement requirement, and adjusting the included angles between the braks and the section of the rotary harrow roller body, the included angles of the braks in the number of microspheres are 9-16 degrees, the directions of the braks are inclined upwards, the included angles of the braks in the number of ¼ are 9-20 degrees, and the directions of the braks are inclined downwards.
The inventor finds that the waste tire pyrolysis oil gas is separated into pyrolysis oil which is easy to store and transport at normal temperature and non-condensable combustible gas at normal temperature, namely pyrolysis gas, by adopting a condensation process, and meanwhile, waste heat steam generated by cooling water is recycled at high quality, and the waste heat steam also needs to meet the requirements of working fluids of devices such as a steam jet pump. The secondary condenser comprises a primary tube sheet type condenser, a secondary tube sheet type condenser, a cyclone separator, a reflux device and a U-shaped liquid seal return pipe, tube bundles in a tube box of the primary tube sheet type condenser and the secondary tube sheet type condenser are also ascending pipes of the natural water circulation loop, pyrolysis oil gas flows along the primary tube sheet type condenser and the secondary tube sheet type condenser from bottom to top, the primary tube sheet type condenser comprises a primary tube pass upper connecting pipe, a primary shell pass lower connecting pipe, a primary tube pass lower connecting pipe, a liquid distribution disc and a primary condensate outlet, the secondary tube sheet type condenser comprises a secondary tube pass upper connecting pipe, a secondary shell pass lower connecting pipe, a secondary tube pass lower connecting pipe and a secondary condensate outlet, and pyrolysis oil gas flows from the primary shell pass lower connecting pipe, the primary shell pass upper connecting pipe, the secondary shell pass lower connecting pipe and the secondary condensate outlet, The secondary shell pass lower connecting pipe and the secondary shell pass upper connecting pipe sequentially flow and are condensed to enter the cyclone separator, in order to prevent the cross flow of pyrolysis gas, a weir plate is designed at a primary condensate outlet, a U-shaped liquid seal is designed at the bottom of the cyclone separator, pyrolysis oil separated by primary condensation is collected at the primary condensate outlet, pyrolysis oil separated by secondary condensation and pyrolysis oil separated by cyclone are all collected to a reflux device and then are conveyed to a liquid distribution disc through a U-shaped liquid seal reflux pipe, the liquid distribution disc comprises a gas distribution plate and a liquid separation cover plate, nozzles on the gas distribution plate correspond to air holes of the liquid separation cover plate one by one, the liquid distribution disc covers the inlet of the primary shell pass lower connecting pipe, pyrolysis gas is sprayed from the nozzles on the gas distribution plate, the pyrolysis oil reflux liquid is injected to be mixed and transfer heat when flowing out through the air holes of the liquid separation cover plate, and the pyrolysis oil condensate refluxed by the secondary shell pass plate type condenser and the cyclone separator is used as a cooling medium, so that the heat exchange area of the condenser is reduced, The equipment investment is reduced, and the full-reflux mode is favorable for recovering pyrolysis gas carrying oil particles and improving the yield of pyrolysis oil. The natural water circulation loop comprises a drum, a header, a downcomer and an ascending pipe, cooling water is infused from the header, a steam and water mixture is generated by the heat exchange of pyrolysis oil gas flowing through the ascending pipe and a shell pass through a primary tube pass lower connecting pipe and a secondary tube pass lower connecting pipe, then the steam and water are separated by injecting the mixture into the drum through a primary tube pass upper connecting pipe and a secondary tube pass upper connecting pipe, and the water returns to the header from the downcomer to complete the natural circulation of the water and simultaneously produce working steam for standby.
Compared with the prior art, the invention at least has the following advantages: firstly, in order to ensure that a waste tire feeding device is in a vacuum, inert gas protection and oxygen-lacking closed environment, a solution of a three-section bell jar feeding mechanism is designed, as the name suggests, the feeding mechanism is isolated into a first-section bell jar storage bin, a middle-section bell jar storage bin and a last-section bell jar storage bin through bell jar sealing, waste tires are crushed into rubber blocks with the size of 3-4 cm, the rubber blocks are conveyed to the first-section bell jar storage bin through a bucket lifting trolley mechanism for temporary storage, the rubber blocks are blown out by inert tail gas through the middle-section bell jar storage bin to extrude carried air, and then the inert tail gas is pumped out through the last-section bell jar storage bin to be in a vacuum state; secondly, the temperature of pyrolysis oil produced by the waste tire pyrolysis reaction furnace is 350-400 ℃, the pyrolysis oil needs to be condensed and fractionated and then is utilized, the condensation is usually realized through a dividing wall type heat exchanger, a cold source generally selects cooling water, the cooling water absorbs heat energy and is converted into steam, the steam with different qualities generated by multi-stage condensation is utilized, the steam can be used as a working fluid source with different pressure levels in a multi-stage steam ejector (pump) and can also be used as cooling steam of an exhaust gas turbine, and the total targets of material balance, water (steam) balance and energy balance in the waste tire pyrolysis process are achieved, and energy sources are saved, emission is reduced, and recycling is achieved; thirdly, in order to ensure that the pyrolytic carbon discharging device after pyrolysis of the waste tire is in a vacuum, inert gas protection and anoxic closed environment, the dynamic seal of the discharging device can solve the technical problems of high-temperature thermal expansion axial deformation, uneven radial movement when heated and friction loss of sealing materials of the discharging disc body, the dynamic seal adopts a mechanical seal structure form, a dynamic ring friction pair is designed on the discharging disc body, a static ring friction pair is designed into a wedge shape, the problem of axial deformation is solved through axial compensation of a spiral spring by a wedge-shaped friction ring, and radial compensation is realized through the design of the friction pair into the wedge shape and elastic deformation of an overlapped blade spring; fourthly, the waste tire pyrolysis oil gas is separated into pyrolysis oil which is easy to store and transport at normal temperature and non-condensable combustible gas which is pyrolysis gas at normal temperature by adopting a condensation process, and simultaneously, waste heat steam generated by cooling water is recycled at high quality, and the waste heat steam also needs to meet the requirements of working fluids of devices such as a steam jet pump and the like; fourthly, as the pyrolysis oil condensate which flows back from the secondary tube plate type condenser and the cyclone separator is used as a cooling medium, the heat exchange area of the condenser is reduced, the equipment investment is reduced, and the full-return mode is favorable for recovering pyrolysis gas carrying oil particles and improving the yield of the pyrolysis oil.
Detailed Description
The invention is further described with reference to the following detailed description of embodiments and drawings.
As shown in fig. 1, fig. 2, fig. 3, fig. 4, fig. 5, fig. 6, fig. 7, fig. 8, fig. 9, fig. 10 and fig. 11, the process system for preparing pyrolysis oil gas by waste tires is characterized in that: the device comprises a vertical pyrolysis tower II, a feeding system I, a discharging system III and a pyrolysis oil gas condenser IV.
The vertical pyrolysis tower II comprises a vertical pyrolysis tower body 33, a rotary rake roller 35, an upper bearing seat 32, a lower bearing seat 36 and a support foot 34, the vertical pyrolysis tower body 33 is provided with a jacket through which high-temperature flue gas at 450-500 ℃ flows, hollow helical blades are designed in the jacket, the high-temperature flue gas spirally rises along a channel formed by the hollow helical blades, the vertical pyrolysis tower body 33 is uniformly heated, the problem that the high-temperature flue gas cannot flow through dead corners of the vertical pyrolysis tower body 33 to cause bulging is solved, a pyrolysis oil gas outlet is designed at the upper part of the vertical pyrolysis tower body 33, and the upper bearing seat 32 and the lower bearing seat 36 are installed at the upper end and the lower end of the vertical pyrolysis tower body 33, so that the coaxiality of the central axes of the vertical pyrolysis tower body 33 and the rotary rake roller 35 is guaranteed.
The rotary harrow roller 35 comprises a rotary harrow roller body 37, an air inlet shaft head 38 and an air outlet shaft head 39, the air inlet shaft head 38 and the air outlet shaft head 39 are respectively designed at the lower end and the upper end of the rotary harrow roller body 35, and the rotary harrow roller body 35, the air inlet shaft head 37 and the air outlet shaft head 38 rotate around the same central shaft.
The inner holes of the air inlet shaft head 37 and the air outlet shaft head 38 are filled with high-temperature smoke of 450-500 ℃, the inner holes are sequentially provided with a heat insulation tile 400, a labyrinth cooling groove 42 and a bearing position 41 from outside, the labyrinth cooling groove 42 comprises a spiral coil 43, a steam-water mixing chamber 44 and a corrugated plate 45, the spiral coil 43 is fixed on the inner wall of the steam-water mixing chamber 44, cooling water enters the steam-water mixing chamber 44 from the spiral coil 43 and is heated, evaporated and vaporized, bubbles generated by boiling collide with the spiral coil 43 and the corrugated plate 45 and are rapidly broken into finer bubbles, so that the bubbles are uniformly distributed in the cooling water, and in other words, the phenomenon that the steam heat conductivity coefficient is too large to cause local overheating of metal on the chamber wall to generate creep deformation is avoided.
The outer surface of the rotary rake roller body 37 is provided with the nails 46 in a spiral line arrangement manner, the included angles between the nails 46 and the section of the rotary rake roller body 37 are adjusted, the nails 46 in the number of nails apply downward thrust to the rubber block along with the rotation of the rotary rake roller body 37, the nails 46 in the number of ¼ apply upward thrust to the rubber block along with the rotation of the rotary rake roller body 37, the nails 46 apply downward thrust to the rubber block to help the asphalt jelly and the steel wire cluster to be smoothly discharged, the resultant force of the two kinds of nails 46 forms a twisting and cutting effect on the rubber block, the pyrolytic carbon hard shell is rubbed to continuously pyrolyze the rubber block, meanwhile, the rubber block accumulation layer is stirred to form gaps, pyrolytic oil gas can escape from the gaps of the accumulation layer, the pyrolytic oil gas flows upwards to transfer heat with the rubber block in the process, and the gas-liquid-solid heat transfer efficiency far exceeds the gas-solid heat transfer efficiency of the rotary rake roller body 37 and the rubber block-solid heat transfer efficiency.
Cross support frames 49 are installed at two ends in the rotary rake roller body 37, the cross support frames 49 fix the helical blades 48 through the tubular shafts 47, high-temperature flue gas rises spirally along a channel formed by the helical blades 48, the rotary rake roller body 37 is heated uniformly, and the problem that the high-temperature flue gas cannot flow through dead corners of the rotary rake roller body 37 to cause bulges is solved.
The feeding system I comprises a bucket lifting trolley mechanism 1 and a three-section type bell jar feeding mechanism 2, wherein the bucket lifting trolley mechanism 1 comprises a self-weighing trolley 3, a lifting track 5 and a pulley traction assembly 4.
The three-section bell jar feeding mechanism 2 comprises an initial-section bell jar storage bin 6, a middle-section bell jar storage bin 7 and a final-section bell jar storage bin 8, wherein the initial-section bell jar storage bin 6 is provided with an initial-section hopper body 9, an upper bell jar 10, an upper bell jar base 11, a hanging rod 12 and a pin shaft assembly 13, the upper bell jar base 11 is arranged at the bottom of the initial-section hopper body 9, the pin shaft assembly 13 is connected with the upper bell jar 11 through the hanging rod 12 to control the upper bell jar 11 to move up and down, and the upper bell jar 10 is matched with a sealing surface of the upper bell jar base 11 to be tightly attached to form upper sealing of the middle-section bell jar storage bin 7; the middle section bell jar storage bin 7 is provided with a middle section hopper body 14, a middle bell jar 15, a middle bell jar base 16, a sling chain 17, a rotary ball assembly 18, an inner and outer compartment assembly 19 and a tail gas recovery buffer tank 20, wherein the middle bell jar base 16 is arranged at the bottom of the middle section hopper body 14, the rotary ball assembly 18 is connected with the middle bell jar 15 through the sling chain 17 to control the middle bell jar 15 to move up and down, the sealing surface of the middle bell jar 15 and the sealing surface of the middle bell jar base 16 are matched and tightly adhered to form a lower seal of the middle section bell jar storage bin 7 and an upper seal of the tail section bell jar storage bin 8, the inner and outer compartment assembly 19 is arranged at the upper part of the middle section hopper body 14, inert tail gas is output from the tail gas recovery buffer tank 20 and enters the middle section hopper body 14 through an outer annular air passage of the inner and outer compartment assembly 19 to be purged, and air in a rubber block gap of a waste tire is extruded and discharged; the tail-section bell jar storage bin 8 is provided with a tail-section hopper body 21, a lower bell jar 22, a lower bell jar seat 23, a suspension wire 24, a pull rod assembly 25 and a multi-stage steam ejector assembly 26, wherein the lower bell jar seat 23 is designed at the bottom of the tail-section hopper body 21, the pull rod assembly 25 is connected with the lower bell jar 22 through the suspension wire 24 to control the lower bell jar 22 to move up and down, a sealing surface of the lower bell jar 22 and the lower bell jar seat 23 is matched and tightly attached to form a lower seal of the tail-section bell jar storage bin 8, the multi-stage steam ejector assembly 26 comprises a first-stage ejector 27, a second-stage ejector 28, a third-stage ejector 29, a middle condenser 30, a last-stage ejector 31, the first-stage ejector 27, the second-stage ejector 28, the third-stage ejector 29, the middle condenser 30 and the last-stage ejector 31 are sequentially connected, and the vacuum degree of the tail-section bell jar storage bin 8 is controlled to be 1000-1300 Pa through continuous multi-stage pressurization.
The inert tail gas is exhaust gas which is obtained by recycling high-temperature flue gas output by the pyrolysis gas combustion kiln and exchanging heat through the vertical pyrolysis tower body 33 and the rotary rake roller 35, and the oxygen content is reduced to be below 3%.
The discharging system III comprises a discharging disc body 55, a water circulation mechanical seal 65 and a ox-head scraper knife discharging assembly 66.
The harrow nails 46 on the roller surface of the rotary harrow roller 35 apply downward thrust to the rubber block to help the asphalt jelly and the steel wire cluster move downward, the harrow nails 46 form a twisting and cutting effect on the rubber block, the pyrolytic carbon hard shell is twisted and broken to enable the rubber block to fully finish the pyrolysis process to form pyrolytic carbon, in order to enable the pyrolytic carbon and the steel wire cluster to smoothly move downward for discharging from the annular reaction chamber between the rotary harrow roller 35 and the vertical pyrolysis tower body 33, the W-shaped discharging tray body 55 is designed to be matched with the annular reaction chamber to receive the pyrolytic carbon and the steel wire cluster, the section of the W-shaped discharging tray body 55 is saddle-shaped, the center of the W-shaped discharging tray body is fixedly connected with the rotary harrow roller 35 and rotates together, and the outer edge of the W-shaped discharging tray body is designed with an annular deep groove, so that the pyrolytic carbon and the steel wire cluster uniformly fall into the annular deep groove of the discharging tray body 55 from the annular reaction chamber.
The water circulation mechanical seal 65 comprises a water tank 50, a moving ring friction pair 51, a static ring friction pair 52, a spiral spring pressing device 53 and a water-cooling discharge pipe 54, wherein the moving ring friction pair 51 is designed on a discharge disc body 55, the static ring friction pair 52 is designed into a wedge shape, the spiral spring pressing device 53 can provide axial and radial compensation for the wedge-shaped friction ring 59, cooling water in the water tank 50 descends through the water-cooling discharge pipe 54 and is injected into the static ring friction pair 52 and the spiral spring pressing device 53, so that the static ring friction pair 52 and the spiral spring pressing device 53 are cooled, a pressure water injection channel 61 and a steam exhaust hole 60 are designed in the wedge-shaped friction ring 59, steam generated when cooling water pressure is injected onto a sealing surface of the friction pair through a water pump for lubrication forms inert gas protection, steam mixture generated when the cooling water injected into the pressure water injection channel 61 is heated rises from the steam exhaust hole 60 to the water tank 50 through a gap of a plate 56 of an overlapped blade spring 64, a natural water circulation loop is formed by a water tank 50, a water cooling discharge pipe 54, a static ring friction pair 52 and a plate 56 clearance channel.
The static ring friction pair 52 comprises a wedge-shaped friction ring 59 and an overlapped blade spring 64, the wedge-shaped friction ring 59 is composed of trisection divided valve rings, the overlapped blade spring 64 comprises an inner ring 58, an outer ring 57 and plates 56, the rectangular plates 56 with the same specification are uniformly distributed around the inner ring 58 in an involute-like manner, each plate 56 is provided with a connecting hole 63, the connecting holes are connected in series through hinges 62 to form two overlapped grid plate curtain belts, the inner ring 58 trisection is tightly attached to the outer circular wall of the wedge-shaped friction ring 59 in an abutting mode, the outer ring 57 and the inner ring 58 are concentric to restrain the grid plate curtain belts composed of the plates 56 in the circular ring between the two, the adjacent two plates 56 are overlapped in sequence, the tail end portion of the front plate 56 serves as a fulcrum of the rear plate 56, the rear plate 56 generates bending deformation around the fulcrum to play a spring role, the elastic deformation direction of each plate points to the circle center, and therefore, the overlapped blade spring 64 can change the width and the width of the plates 56, The thickness of the tail end of the plate 56 adjusts the radial compensation amount of the sealing friction pair, and the radial compensation amount is close to the value of the distance between the inner ring 58 and the outer ring 57 and the thickness of the tail end of the plate 56, so that the radial compensation with limited working space is facilitated.
Ox head spiller ejection of compact subassembly 66 includes spiller 68, shaftless helical blade 67, ox head discharge gate 69, because ejection of compact disk body 55 concreties and together revolves with gyration rake roll 35, and pyrolytic carbon and steel wire group are shoveled by the spiller 68 of slope installation, and the shaftless helical blade 67 of installing with spiller 68 parallel is rotatory scrapes into ox head discharge gate 69 with pyrolytic carbon and steel wire group, avoids steel wire group jam ox head discharge gate 69.
The pyrolysis oil gas condenser IV comprises a secondary condenser 70 and a water circulation loop 71.
The secondary condenser comprises a primary tube plate type condenser 72, a secondary tube plate type condenser 73, a cyclone separator 74, a reflux device 75 and a U-shaped liquid seal reflux pipe 76, tube bundles in tube boxes of the primary tube plate type condenser 72 and the secondary tube plate type condenser 73 are also ascending pipes 80 of a water circulation loop, pyrolysis oil gas flows along the primary tube plate type condenser 72 and the secondary tube plate type condenser 73 from bottom to top, the primary tube plate type condenser 72 comprises a primary tube pass upper connecting pipe, a primary shell pass lower connecting pipe, a primary tube pass lower connecting pipe, a liquid distribution disc and a primary condensate outlet, the secondary tube plate type condenser comprises a secondary tube pass upper connecting pipe, a secondary shell pass lower connecting pipe and a secondary condensate outlet, the pyrolysis oil gas flows from the primary shell pass lower connecting pipe, the primary shell pass upper connecting pipe, the secondary shell pass lower connecting pipe and the secondary shell pass upper connecting pipe in sequence, is condensed and enters the cyclone separator 74, in order to prevent the flow of pyrolysis gas, a weir plate is designed at the outlet of the primary condensate, a U-shaped liquid seal is designed at the bottom of the cyclone separator 74, pyrolysis oil separated by primary condensation is collected to the outlet of the primary condensate, pyrolysis oil separated by secondary condensation and pyrolysis oil separated by cyclone are all collected to the reflux device 75 and then are conveyed to a liquid distribution disc through a U-shaped liquid seal reflux pipe 76, the liquid distribution disc comprises a gas distribution plate and a liquid distribution cover plate, nozzles on the gas distribution plate correspond to air holes of the liquid distribution cover plate one by one, the liquid distribution disc covers the inlet of the lower connecting pipe of the primary shell side, pyrolysis gas is sprayed out from the nozzles on the gas distribution plate, and the pyrolysis oil reflux is injected to mix and transfer heat when flowing out through the air holes of the liquid distribution cover plate.
The water circulation loop 71 comprises a drum 77, a header 78, a downcomer 79 and an ascending pipe 80, cooling water is infused from the header 78, flows through the ascending pipe 80 through a primary tube side lower connecting pipe and a secondary tube side lower connecting pipe to exchange heat with pyrolysis oil gas of a shell side to generate a steam and water mixture, then is injected into the drum 77 through a primary tube side upper connecting pipe and a secondary tube side upper connecting pipe to realize steam and water separation, water returns to the header 78 from the downcomer 79, and working steam is produced for standby while natural circulation of the water is completed.
Variations and modifications to the above-described embodiments may occur to those skilled in the art, which fall within the scope and spirit of the above description. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and variations of the present invention should fall within the scope of the claims of the present invention. Furthermore, although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.