RU2416053C2 - Device for processing - low temperature pyrolysis - hydrocarbon-containing solid and liquid domestic, industrial and forestry wastes - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: device for processing - low temperature pyrolysis of hydrocarbon-containing solid and liquid wastes consists of two sealed horizontal reactors mounted one above another, also drying reactor is an upper one, while pyrolysis reactor is a lower one. The reactors are equipped with screw feeders, with chambers for collection of processed product, with channels of steam-gas mixtures exhaust, with a screw unloader of solid material from the pyrolysis chamber and with a smoke fumes exhaust. The reactor of pyrolysis is furnished with gas burners for heating to 450-500°C. Blade screws are mounted on fixed hollow axles in the reactors, while a gas burner is installed into the hollow axle of the pyrolysis reactor. The drying reactor is heated to 150-200°C from outside with smoke fumes, temperature of which is controlled by means of network of pipes arranged between the reactors and by pumping cold air and/or process gas through them, also by pumping heated gases through the hollow axle. Semi-tubes are welded on a case of the reactor from beneath. Process gas is pumped via orifices in the case of the reactor and via these semi-tubes into the cavity of the reactor. Rotary blade screws are combined out of two opposite wound and inter-welded bands at a similar pitch; they rotate on the fixed axle. Blades are welded to a vertical band which is wound along an upper band. On ends the blades of the screws have scrapers positioned with a back incline.

EFFECT: prevention of accumulation of crust and scale on working surfaces of device.

1 cl, 1 dwg

Description

The processing device (low-temperature pyrolysis) of hydrocarbon-containing solid and liquid household, industrial, agricultural, forest and other wastes - environmentally friendly, compact, modular type, punched in control, high-performance, with high thermal efficiency capable of processing solid waste, various polymeric materials, rubber products waste from the timber industry, sawdust, shavings, peat, waste from cattle breeding, pig breeding, poultry farming, field cultivation, oil processing, paper mill waste, waste coal sludge collectors and other products, as well as mountains of existing and old landfills, which will further solve the problem of cleaning our land from garbage, reclaim land occupied by landfills, enable nature to clean underground water under landfills and surrounding areas and get a significant amount energy carriers that are constantly replenished due to human activity, and not biofuels due to the withdrawal of sown areas.

Currently, there are many methods of solid waste disposal and so forth. Wastes. An example is the MARINE WASTE FURNACE FURNACE, SU 1315737, the main purpose of which is the occasional (as various types of waste accumulate in the storage bins), the product is burned with the release of combustion products into the atmosphere without receiving and further using the secondary product by heating the product coming sequentially into three heated screw chambers, where the product is warmed up, dried, crushed, wakes up through openings in the chamber housings on the grates for afterburning with partial use diesel fuel.

In (19) RU (11) 96110679 (13) And the applicants describe the retort method, i.e. loading the tank, sealing it with a leak test, loading the tank into the heating chamber, heating, cooling, unloading. The disadvantages of the retort method are cyclicality, low efficiency, difficulty in maintaining the thermal regime.

In (19) RU (11) 2075272 (13) C 1, an attempt was made to implement a continuous processing method combined with drying and deep high-temperature processing in one three-section horizontally located reactor. It is doubtful usefulness and viability of this device, because Valuable product is obtained by pyrolysis and gasification is directed into the furnace (chamber warming). With the trapezoidal section of the heat treatment chamber, it is impossible to create the tightness of the separated drying, pyrolysis and afterburner chambers, the vapor-gas mixture under pressure will find a way out, which will disrupt the process, scale, deposit, coking of the inner surfaces of the chambers due to the lack of a product promotion mechanism and surface cleaning.

The closest in theory to the device I proposed is (19) RU (11) 2202589 (13) С 2. The disadvantages are;

a) it is necessary to have three reactors; drying, pyrolysis, afterburning, the reason is rains, snow, high humidity of the product (in the given example No. 1 moisture 21% of the mass of the processed product, may be much more);

b) the technical impossibility of creating reliable tightness of a rotating reactor heated to a temperature of 600 ° C (claim 5) with a diameter of up to 3000 mm, with t igniting a gas-vapor hydrocarbon-containing medium of the order of 300-360 ° C and having a gas-vapor medium of 600 degrees in the pyrolysis chamber , if the tightness system is broken and gas breaks into the atmosphere, we get a fire torch, when we try to extinguish, we get the reactor cooling, rarefaction in the reactor, a sharp suction of atmospheric air and an explosion - it is explosive;

c) the vapor-gas flow from the collection chambers will pick up solid microscopic particles, which will quickly clog the SR-1 catalysts and disable them;

g) if necessary drying created reactor will operate with impaired environmental requirements, since heating and drying of the product is carried out directly by flue gases of elevated temperature, the effect of which on polymeric materials will cause a violent fusion reaction, a change in the chemical state with the release of harmful poisonous gases and their release (according to the patent) together with steam into the atmosphere;

e) how and what to separate from each other - thermal insulation from the heating layer or the heating layer from the reactor vessel for the implementation of the rotation of the reactor, with the initial structural laying of temperature deformations;

f) causes great concern the viability of the afterburner reactor at t 1200 ° C (indicated several times in the description) and even t at 850 ° C, indicated in two examples, especially the cantilever version of the screw (according to the drawing);

g) according to example No. 1; pyrolysis of 400-500 ° C (when the reactor is heated by pipes located inside the reactor), when the reactor is rotated by strips, the product will be picked up and thrown onto pipes heated to 400-500 ° C, forming scale, soot, coking, loss of a rather low efficiency, failure in all due to lack of cleaning devices from carbon and okoksovaniya.

An attempt was made to continuously conduct the processing of solid waste into SU 1548601, but questions regarding the operability and quality of the resulting secondary product are questionable;

a) in the example given - paper, cardboard, wood, etc. Who can guarantee that in the back of a garbage truck there will not be two, three, or eleven sectional heating batteries, pipe cuts for heating and water pipes, gas and electric water heaters replaced in apartments, but there are still some items that can be in the garbage truck, including concrete, reinforced concrete and other pieces, wire, then what kind of power should be a chopper, because the metal extraction according to the patent is carried out after pyrolysis from the solid component, and if all this does not get stuck in the grinder feeder;

b) how the product of pyrolysis will pass through the airlock and the bell, having a bend of 90 °, in the absence of a mechanism for this promotion;

c) drying, heating and pyrolysis of the product are carried out in one reactor, then why separate the heating chambers of the product into sections, because all the same, the vapor-gas mixture is unloaded from the reactor together with moisture (water) after drying the product, and its humidity can be up to 50% and higher of the weight of the whole product (waste water residues);

d) H ₂ O can be decomposed into H and O by the electrolytic method or by heating to 2000 ° at high pressures, but this is difficult to implement, because they immediately enter the oxidation reaction, so when drying a very wet product, you need a device for separating water from the rest of the product, otherwise there will be big problems when burning gas;

d) an important factor in this device is that all the resulting secondary product is used directly for the operation of the turboelectric generator without the accumulation of liquid fraction;

f) spiral winding inside the conveying pipe will promote the product only when the conveying pipe itself rotates, in this case when pieces of metal, concrete, stone get into the reactor up to 10 cm (according to the patent), it will contribute to the formation of dead zones, scale, soot, coking in the lower part of the reactor in the spaces between the holes at low gas pressures, which will subsequently lead to a gradual decrease and overlap of the lower holes, redirecting the gas flow to the upper holes, where it is less tion product, as heavy pieces of rock will settle down below. Installation (as an option) in the conveying pipe of the screw with a continuous spiral and holes in the axis and only (in FIG. 3), not according to the size of the inner diameter of the conveying pipe, taking into account some technological clearances in the manufacture and temperature deformations, namely according to the specified drawing , will not interfere with the processes of formation, scale, carbonization and coking at low gas pressures in the spaces between the holes with a gradual decrease and corking them, starting from loading with progress to unloading, which will lead to a fall Device efficiency. And what kind of power - capacity should there be compressors in order to provide the outlet pressure of the directed gas jets through many holes in the reactor vessel and hollow axis (according to the drawing) with t 500 ° C and a pressure of 20 kg / cm ² , especially on pages 21-28 / 12 / descriptions (pyrolysis at elevated temperatures 800-1000 ° C) and, accordingly, blowers. Implementation of tedding and promotion of the product at low pressures is impossible, only purging to warm the product.

The disadvantage of a screw feeder in RU 2100402 is that changing the pitch of the tape winding to seal the product in the middle part of the screw will lead to the fact that. having a multi-faceted profile of the screw housing or a longitudinal finning inside the housing at the place of the changed screw pitch and further, to prevent product scrolling with the screw, will create the prerequisites for the product to be ejected through the feeder in the absence of the product in the vertical supply shaft, which is fraught with the passage of the vapor-gas mixture under excessive pressure in a reactor at a temperature of 500 and above degrees, at a flash point of a steam-gas mixture of the order of 360-380 degrees.

The device I offer is the most progressive, because makes it possible during the spring-summer and autumn period to accumulate in sufficient quantities energy sources in the form of a liquid and solid component for use in winter, sowing and harvesting straddles, providing heat and electricity to sewage treatment plants in cities and agricultural enterprises. The solid component can be used in the heating season, because it is equal in calorific value to anthracite, both in the desired form and in gaseous, passing it through a gas generator furnace, has long been used in industrial and domestic needs. The gas component can be directly used to meet the needs of environmentally friendly production of heat and energy supply.

This device provides for the elimination of the above disadvantages. Recycling product entering bunker 11, which has passed through a technological line for sorting and preparing solid waste for pyrolysis, which provides for the removal of ferrous and non-ferrous metals, concrete, stones, glass, etc., non-recyclable waste with a maximum particle size of 50 mm (textolite, ebonite, etc. polymer and wood material) is heated by the exhaust flue gases in the hopper 11, then it is compacted by a screw feeder 10 and fed to the drying reactor 22, where it is intensively mixed by the blades 16 of the screw 9 with the already heated product and, and due to the pumped, heated process gas through the fixed axis of the screw 9 with openings 12, in the literal sense, the product will be susceptible to shock heating to 150-200 ° C, transferring moisture to the exhaust gas through chimney B. The feeder auger has a constant tape winding step and at the end , one third of the length, has a cone with an outlet 4-5 times smaller than the cross-sectional area to the cone, with a pipe of the same section extending 250-300 mm in length. The sealed product in this pipe will be a shut-off device for the vapor-gas mixture to exit the drying and pyrolysis reactor, as well as for the suction in atmospheric air reactors, even if there is no product in the receiving hopper 11, 7 and 14. The greater the pumped gas and its temperature is higher, the greater the need to apply the product to dry, i.e. higher will be performance. The half-pipes welded to the reactor vessels are used for heating and pumping process gas through them, balancing jumps and stabilizing the temperature conditions of the process, as well as for increasing the rigidity of the reactor vessel structure in order to reduce, as far as possible, the effects of temperature deformations. Bladed augers, with a small angle of attack of the blades, mix the product along the entire length of the reactors and propel it forward, the product warms up as moisture returns, decreasing in weight and volume. At the end, the screws have 2 turns of blades with reverse winding and an opposite angle of attack, so that a delay is accumulated of the processed product for more complete processing and its delivery to the receiving hopper 7, 14. The blades 16 are made according to figure 1, the scrapers 19 are welded to the end of the blade with a slope back so that adhering or catching products can be discharged from the blades and scrapers, which are designed to remove scale and carbon from the inner wall of the reactor. At small angles of attack of the blades, an increase in the number of revolutions of the screws is possible to create better conditions for the drying and pyrolysis reactions. The screw itself is subject to self-cleaning due to rolling of the product along the blades, axis and screw. Collisions coarse product particles among themselves contribute to the destruction of major parts of the product. Due to the fact that the base of the blade screws is not continuous, it is possible to let the heated gases through the holes in the axes, thereby contributing to the removal of dead zones of the screws and better heating of the mixed product. When the product touches the fixed axes, it warms up and, accordingly, the prerequisites for the formation of scale, carbon deposits and coking appear on the surface of the axes. Together with the captured small particles of the product, when rotating the screw, scale, carbon deposits and coking are used as a lubricant. Rotation of the auger with large surface voids along a fixed axis with holes will help to clean the holes and prevent the formation of scale, carbon deposits and coking both on the axes and on the inner surface of the reactors. It is precisely according to the above conditions that such a design of a blade auger with a fixed axis is selected that allows you to get away from the cantilever design of the screw, increase the rigidity of the screw for working at high temperatures, allows you to get away, as far as possible, from increased temperature deformations, reduce the specific loads of heated parts, reduce the possibility of scale formation, carbonization, blockage of the gas purge holes, ease of manufacture, increase the reliability and maintainability of the device. According to environmental conditions, the gas-vapor mixture from the drying reactor 22 and the collector 7 through outlet A is fed through a purification cyclone to a water collection condenser, and gas is supplied to the compressor and / or immediately to be heated and again to the drying reactor, and so on, in a circle, excess enriched gas from receivers are fed to a gas burner. Condensed liquid is collected in a tank, subjected to physico-chemical treatment, purification - filtration through a filter filled with a solid component obtained as a result of pyrolysis, and is recycled, when replacing the filler, the old one is sent for recycling.

The product, dried and warmed up to 200 ° C, from the receiving chamber 7 is fed by the feeder 5 to the pyrolysis chamber of the reactor 23, where it is intensively mixed with the product already warmed up, propelled forward into the collection chamber 14 and heated up to 450-500 ° С by gas burners 1 outside the reactor through the hollow axis of the reactor with a burner 6 and pumped heated gas through half pipes 2 and holes welded to the body 4. The gas-vapor mixture from the reactor 23 is fed for further processing — a cyclone, with or without a catalyst, a liquid fraction cooler-separator of temperature and gas (not shown, because there are many proven and inventive distillation and cracking devices). Overpressure in reactors of 5-10 mm Hg is achieved by supplying the reactor with heated process gas and suction of the gas mixture with fans or compressors.

The solid fraction is unloaded from the receiver 14 by the discharge screw 15. A set of pipes with inlets C installed between the reactors designed to heat the process gases and atmospheric air and reduce the temperature of the heating of the drying reactor.

Sealing of reactors is achieved due to the compacted product in the nozzles of the loading and unloading feeders, as well as due to seals with stuffing box packing (not shown in the drawing) from an asbestos cord impregnated with graphite or molybdenum high-temperature grease in the bearing area between the fixed end of the reactors protected against overheating in the area of the bearing with a water jacket (not shown in the drawing) - a rotating neck of the screw and a fixed axis.

Reactor shells, fixed axes, screws, welded half tubes and gas burner designs are made of heat-resistant, highly alloyed metal from the conditions of the lowest temperature deformations at temperatures of 450-600 ° C with a length of reactors, depending on the size, 3-6 m.

The reactors are located inside a metal lined with refractory material, with external thermal insulation protection 3 with gas burners 1 mounted in it and gas inlets F.

The diameter of the drying reactor depends on the size of the designed module for productivity (availability and renewability of the product), taking into account the fact that the product yield from the drying reactor is 20-50% less than the weight of the loaded product, depending on the humidity and composition of the product.

The diameter of the pyrolysis reactor is designed taking into account the output of the steam-gas mixture of about 60-65% of the weight loaded into the reactor of the dried product, i.e. pyrolysis reactor sectional area should be 40-50% less than the sectional area of the drying reactor.

The duration of the pyrolysis reaction in the reactor of a product already warmed up to 200 ° С with rapid (shock) heating up to 450-500 ° С is about 25-45 minutes, depending on the supported temperature conditions, the allowed size of the product pieces, taking into account this, we can calculate the diameters, length reactors and module performance.

DESCRIPTION OF THE DRAWING

1. Gas burners and air supply pipes.

2. The half-tube welded to the reactor, for heating the process gas.

3. Refractory lining and thermal insulation.

4, 12. The openings for the passage of the hot process gas in the reactor.

5, 10. Screw loaders with gear.

6. E. Gas burner in the hollow axis of the screw.

7. Collection of dry product.

C. Process gas and air outputs.

8. Fireproof jumper.

9, 13. Paddle auger.

A. The output of the gas mixture from the drying reactor.

11. Heated loading hopper.

B. Exhaust flue gas output.

D. The output of the gas mixture from the pyrolysis reactor.

14. The collection of solid fractions.

16. Auger unloading.

17. Transverse winding, welded onto a planar winding 20 with a pitch of 350-500 mm strip 100 * 10 mm.

18. Flat winding strip 100 * 10 along the pipe axis of the screw with a diameter of 250-300 mm for the length of the reactor opposite winding 20.

19. Scraper cleaning.

20. Plane winding over winding 18 in the opposite direction and welded to strip 18.

21. Torches of gas burners.

22, 23. Reactor shells.

F. Gas and air inlets for gas burners.

Claims (1)

A processing device for low-temperature pyrolysis of hydrocarbon-containing solid and liquid wastes, containing 2 sealed horizontal reactors installed one above the other, one of which is a drying reactor top, the other a pyrolysis reactor bottom, equipped with screw feeders, processed product collection chambers, vapor-gas mixture exit channels, screw unloader of a solid component from the pyrolysis chamber, a flue gas exit channel, gas burners for heating the pyrolysis reactor to 450-500 ° C, characterized in so that fixed hollow axes are installed in the reactors, on which rotary screws are mounted, a gas burner is inserted into the hollow axis of the pyrolysis reactor, the drying reactor is heated to 150-200 ° C from the outside by flue gases, the temperature of which is regulated by a network of pipes installed between the reactors and pumping cold air therethrough and / or process gas and the injection of heated gases through the hollow spindle; half pipes are welded to the bottom of the reactor vessel for pumping process gas through them into the reactor cavity through openings in the reactor vessel; rotating paddle screws are assembled from two strips opposite to each other and welded together with the same pitch with the possibility of rotation on a fixed axis, a vertical strip is wound along the upper strip and everything is welded into one working unit, and the blades are already welded to the vertical strip; the auger blades at the ends have scrapers mounted with a slope back in such a way as to ensure that scale, coke and coking formed on the augers and axes are used as a lubricant.