CN116474674A - Polyurethane recycling method and process system - Google Patents

Abstract

The invention discloses a polyurethane recovery method and a process system, which relate to the technical field of waste polyurethane recovery, in particular to a polyurethane recovery process system. According to the polyurethane recycling method and the process system, the polyether polyol is separated and purified by adopting the secondary separation and secondary filtration method, compared with the traditional primary separation and filtration method, the finished product solid content is lower than 1%, the waste gas and toxic gas content is lower than 0.5%, the product purity is higher, and the reboamed polyurethane foam has stable structure, good weather resistance and good heat resistance stability.

Description

Polyurethane recycling method and process system

Technical Field

The invention relates to the technical field of waste polyurethane recovery, in particular to a polyurethane recovery method and a process system.

Background

The global environment is polluted by a large amount of waste chemical products, and the carbon emission of the waste chemical products is large, so that the global warming process is aggravated. Polyurethane in chemical products is used as a sixth large synthetic material, and is widely applied to the fields of automobiles, refrigerator manufacturing, transportation, civil construction, shoes, synthetic leather, fabrics, aviation, medical treatment, petrochemical industry and the like, and the market of polyurethane products is steadily rising at the moment, wherein the polyurethane is mainly generated by reacting polyisocyanate and polyhydroxy compounds. Polyurethane structures comprise soft and hard segments whose properties are tailored by modifying the chemistry and proportions of the soft and hard segments to suit a particular application, the primary application forms of polyurethane include soft foams, rigid foams, elastomers, coating agents, adhesives and sealants.

However, the polyurethane recycling method includes several methods such as burial, incineration, physical pulverization, heat treatment and chemical treatment: burial can cause soil and water pollution; incineration causes air pollution; the polyurethane after physical crushing can only be used as filling material, and the utilization value is not high; the heat treatment can generate various toxic gases; in comparison, chemical treatment is an ideal recycling method, and known polyurethane chemical degradation methods include hydrolysis, alcoholysis, amination, acidolysis, alkali and thermal degradation. The alcoholysis method is used as a method for chemically recycling polyurethane waste foam which is most widely applied, micromolecular alcohol is used as an alcoholysis agent, and in the temperature range of 150-300 ℃, the urethane bond in polyurethane molecules and dihydric alcohol are subjected to alcohol transesterification reaction, so that the urethane bond is broken to generate long-chain polyol and micromolecular compound, the recycling of the waste polyurethane is still remained in a test stage at present, and the process experience of a related large-scale industrialized waste polyurethane recycling production line is lacked.

Disclosure of Invention

The invention provides a polyurethane recycling method and a process system, which solve the problems of the background technology.

In order to achieve the above purpose, the invention is realized by the following technical scheme: the utility model provides a process system that polyurethane was retrieved, polyurethane recovery line includes raw materials district, reaction zone, finished product district, the reaction zone is by crushing equipment, conveying equipment, screening equipment, reation kettle, condensation equipment, raw materials reserve tank, pre-heat cauldron, sedimentation tank, filter equipment, dealcoholization distillation cauldron, homogeneity cauldron, finished product holding vessel, abandonment spray equipment and constitutes, crushing equipment comprises conical hopper, dustproof airtight cover, broken blade and engine number one, conveying equipment comprises conveyer belt and engine number two, screening equipment includes engine number three, the output shaft of engine number three is by cylindrical mechanism, screening equipment is connected with reation kettle.

Optionally, the output shaft of the first engine is fixedly connected with the crushing blade, the crushing blade is arranged in the center of the conical funnel, and the conical funnel is connected with the transmission device.

Optionally, the conveying device is placed at an inclination of 30 degrees, and the end of the conveyor belt in the conveying device is connected with the screening device.

Optionally, the inside is one deck screen cloth, outside in the cylinder structure, take screw thread form cylinder steel construction.

Optionally, the top of reation kettle is provided with the pay-off mouth, and the pay-off mouth is used for receiving broken old and useless polyurethane powder after the screening and the polyol after preheating, reation kettle's top fixed mounting has condensation equipment, and condensation equipment is used for retrieving polyol steam, reation kettle inside is equipped with electromagnetic heating equipment, oil-out, water inlet and discharge gate, the oil-out is located reation kettle jar body intermediate wall face, the discharge gate is located the reation kettle bottom, hydraulic jetting device is connected to the water inlet, the sedimentation tank is connected to the discharge gate, and the other end and the filter equipment of sedimentation tank are connected.

Optionally, a coil is used for heating in the preheating kettle, heat conduction oil is used in the coil, and the heat source is electrically heated.

Optionally, the filtering device consists of a filter cake and an active carbon filtering device, and the filtering device is connected with the dealcoholization still.

A process for polyurethane recovery comprising the following operative steps;

s1, filling the waste polyurethane material into a conical hopper of crushing equipment in an artificial mode, and crushing the waste polyurethane material by a crushing blade after electrifying, wherein the waste polyurethane material is sourced from a waste refrigerator, a building heat preservation layer, a helmet, a waste motorcycle, a waste automobile, a sofa and industrial equipment.

S2, conveying the crushed waste polyurethane powder to screening equipment through a conveyor belt, separating the large waste polyurethane foam from the small waste polyurethane powder through a screen, taking the large waste polyurethane foam out of the screen, recharging the large waste polyurethane foam into a hopper of the crushing equipment, and crushing again.

S3, conveying the crushed waste polyurethane fine powder into a reaction kettle through a feed inlet at the top end of the reaction kettle for alcoholysis reaction.

S4, firstly sending the polyol raw material into condensing equipment at the top end of the reaction kettle through a feed pump 1 to perform primary preheating to preheat the polyol to 25-50 ℃, simultaneously recovering polyol steam incompletely reacted through the condensing equipment, and re-pumping the condensed and recovered liquid polyol into the reaction kettle.

S5, pumping the first-stage preheated polyol solution into a preheating kettle, and carrying out secondary heating on the polyol in a coil heating mode to 50-80 ℃.

S6, adding crushed waste polyurethane powder and preheated polyol into a reaction kettle, adding an alcoholysis assisting agent, and heating to 100-180 ℃ in an electromagnetic induction heating mode.

S7, opening an oil outlet of the reaction kettle, flowing out unreacted black oil which is completely and partially floating, performing primary separation, introducing polyether polyol after alcoholysis reaction into a sedimentation tank, performing physical sedimentation for 6-8 hours, removing unreacted waste polyurethane powder and fine solids, and performing secondary separation.

And S8, the settled polyether polyol passes through a filtering device, primary filtering is carried out on a filter cake, and then secondary filtering and adsorption are carried out through an active carbon device, so that the finished polyether polyol is obtained.

And S9, feeding the filtered polyether polyol into a dealcoholization distillation kettle through a pipeline, dealcoholizing, and heating to 220 ℃ by using a superaudio heater, wherein the polyol in the solution is changed into steam.

S10, arranging a pipe outlet above the reaction kettle, connecting a secondary condenser, controlling the cooling temperature of the primary condenser to be 100-120 ℃ according to the boiling point of the polyol, enabling part of organic waste gas to become liquid, and controlling the cooling temperature of part of organic waste gas to be about 30-40 ℃ through the secondary condenser.

S11, flowing the condensed organic matter liquid into a recovery tank; after the dealcoholization distillation reaction is finished, the recovered alcohol is recycled to the production of the next batch for use, and the recovered alcohol is directly used as a raw material without treatment.

S12, taking a certain amount of polyether polyol, sequentially adding a foam stabilizer, a catalyst and a foaming agent, uniformly stirring, adding black materials according to a certain proportion, rapidly stirring, standing to naturally foam,

wherein the addition amounts of the foaming agent, the catalyst and the stabilizer are respectively 5-20%, 0.5-10% and 0.1-5% of the mass of the polyether polyol.

The invention has the following beneficial effects:

1. the polyurethane recycling method and the process system adopt a normal pressure condensation circulation reaction device system and are provided with a waste heat recycling device, and the reaction system is safe, energy-saving and consumption-reducing. The condensing device is placed at the upper end of the reaction kettle, the polyol steam is condensed and recycled, the polyol in the raw material storage area is subjected to primary preheating through the absorbed waste heat, the waste heat of the polyol steam is effectively utilized, the energy consumption of integral preheating of the polyol is reduced, the equipment volume of the preheating kettle is reduced, the system operation program is simplified, and the reaction device system is safer and more reliable than the traditional high-pressure heating reaction.

2. The polyurethane recycling method and the process system have the advantages that the advanced electromagnetic heating mode is adopted in the reaction kettle, the heating reaction time is fast, the control is easy, the temperature is fast in lifting during heating, the heating temperature is stable, the operation cost is low, a large amount of carbon dioxide is not discharged during heating by the traditional boiler, the occupied area of heating equipment is small, the electric heating mode is safer, the production efficiency is higher, the efficiency is improved by more than 30 percent compared with that of the traditional heating mode, the energy is saved, the environment is protected, and the heat energy is saved by 35 percent compared with that of the traditional heating mode.

3. According to the polyurethane recycling method and the process system, the polyether polyol is separated and purified by adopting the secondary separation and secondary filtration method, compared with the traditional primary separation and filtration method, the finished product solid content is lower than 1%, the waste gas and toxic gas content is lower than 0.5%, the product purity is higher, and the reboamed polyurethane foam has stable structure, good weather resistance and good heat resistance stability.

Drawings

FIG. 1 is a flow chart of the present invention;

FIG. 2 is a flow chart of the recovery treatment of waste polyurethane in the invention.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

Referring to fig. 1 and 2, the present invention provides a technical solution: the polyurethane recycling production line comprises a raw material area, a reaction area and a finished product area, wherein the reaction area consists of crushing equipment, conveying equipment, screening equipment, a reaction kettle, condensing equipment, a raw material storage tank, a preheating kettle, a sedimentation tank, a filtering device, a dealcoholization distilling kettle, a homogenizing kettle, a finished product storage tank and waste spraying equipment, the raw material storage tank is used for storing preheated polyol, the polyol in the polyol storage tank of the raw material storage area is pumped to the preheating kettle through a feed pump 1, the preheated polyol is pumped from the bottom of the preheating kettle through a feed pump 2 and is subjected to combined screening, waste polyurethane powder is pumped into the reaction kettle, the crushing equipment consists of a conical hopper, a dustproof closed cover, crushing blades and a first engine, the conveying equipment consists of a conveying belt and a second engine, the screening equipment comprises a third engine, an output shaft of the third engine is connected with the reaction kettle, the screening equipment is free of three wastes in the preparation process, the polyurethane recycling rate reaches 95%, degradation products can be directly utilized without subsequent treatment, and the cost of the polyurethane foam products is greatly reduced. Therefore, the invention has strong practicability on the comprehensive utilization of wastes in the whole polyurethane industry, and has higher economic and environmental protection values and good social benefits.

An output shaft of the first engine is fixedly connected with the crushing blade, the crushing blade is arranged in the center of the conical funnel, and the conical funnel is connected with the transmission equipment.

The conveyor is placed at an inclination of 30 degrees, and the conveyor belt ends in the conveyor are connected to the screening device.

The inside of the cylindrical structure is provided with a layer of screen, the outside of the cylindrical structure is provided with a threaded roller steel structure, and the screen can adopt a screen with 10 meshes to 100 meshes according to the subsequent reaction requirements.

The top of reation kettle is provided with the pay-off mouth, and the pay-off mouth is used for receiving broken old and useless polyurethane powder after the screening and the polyol after preheating, and reation kettle's top fixed mounting has condensation equipment, and condensation equipment is used for retrieving polyol steam, and reation kettle is inside to be equipped with electromagnetic heating equipment, oil-out, water inlet and discharge gate, and the oil-out is located reation kettle jar body interwall face, and the discharge gate is located the reation kettle bottom, and hydraulic jetting device is connected to the water inlet, and the sedimentation tank is connected to the discharge gate, and the other end and the filter equipment of sedimentation tank are connected.

The preheating kettle is internally heated by adopting a coil pipe, the coil pipe is internally heated by adopting heat conduction oil, and the heat source form is electric heating.

The filter device consists of a filter cake and an active carbon filter device, and the filter device is connected with the dealcoholization distillation kettle.

A process for polyurethane recovery comprising the following operative steps;

s1, filling the waste polyurethane material into a conical hopper of crushing equipment in an artificial mode, and crushing the waste polyurethane material by a crushing blade after electrifying, wherein the waste polyurethane material is sourced from a waste refrigerator, a building heat preservation layer, a helmet, a waste motorcycle, a waste automobile, a sofa and industrial equipment.

S2, conveying the crushed waste polyurethane powder to screening equipment through a conveyor belt, separating the large waste polyurethane foam from the small waste polyurethane powder through a screen, taking the large waste polyurethane foam out of the screen, recharging the large waste polyurethane foam into a hopper of the crushing equipment, and crushing again.

S3, conveying the crushed waste polyurethane fine powder into a reaction kettle through a feed inlet at the top end of the reaction kettle for alcoholysis reaction.

S4, firstly sending the polyol raw material into condensing equipment at the top end of the reaction kettle through a feed pump 1 to perform primary preheating to preheat the polyol to 25-50 ℃, simultaneously recovering polyol steam incompletely reacted through the condensing equipment, and re-pumping the condensed and recovered liquid polyol into the reaction kettle.

S5, pumping the first-stage preheated polyol solution into a preheating kettle, and carrying out secondary heating on the polyol in a coil heating mode to 50-80 ℃.

S6, adding crushed waste polyurethane powder and preheated polyol into a reaction kettle, adding an alcoholysis assisting agent, and heating to 100-180 ℃ in an electromagnetic induction heating mode.

S7, opening an oil outlet of the reaction kettle, flowing out unreacted black oil which is completely and partially floating, performing primary separation, introducing polyether polyol after alcoholysis reaction into a sedimentation tank, performing physical sedimentation for 6-8 hours, removing unreacted waste polyurethane powder and fine solids, and performing secondary separation.

And S8, the settled polyether polyol passes through a filtering device, primary filtering is carried out on a filter cake, and then secondary filtering and adsorption are carried out through an active carbon device, so that the finished polyether polyol is obtained.

And S9, feeding the filtered polyether polyol into a dealcoholization distillation kettle through a pipeline, dealcoholizing, and heating to 220 ℃ by using a superaudio heater, wherein the polyol in the solution is changed into steam.

S10, a pipe outlet is arranged above the reaction kettle and is connected with a secondary condenser, the cooling temperature of the primary condenser is controlled to be 100-120 ℃ according to the boiling point of polyol, part of organic waste gas becomes liquid, and part of organic waste gas passes through the secondary condenser, the cooling temperature is controlled to be about 30-40 ℃, polyol components in the finished polyether polyol are recovered by adopting secondary condensation, and compared with the traditional primary condensation equipment, the secondary condensation is recovered according to the characteristic that the boiling points of various polyols in the product are different, the product purity can be further improved, and meanwhile, the condensation efficiency of the secondary condenser can reach more than 99%.

S11, flowing the condensed organic matter liquid into a recovery tank; after the dealcoholization distillation reaction is finished, the recovered alcohol is recycled to the production of the next batch for use, and the recovered alcohol is directly used as a raw material without treatment.

S12, taking a certain amount of polyether polyol, sequentially adding a foam stabilizer, a catalyst and a foaming agent, stirring uniformly, adding black materials according to a certain proportion, stirring rapidly, standing to naturally foam the obtained regenerated polyurethane foam, ensuring safety and environmental protection, avoiding three wastes discharge in the use process, preparing end products such as heat insulation materials, automotive interiors and the like, having extremely high ecological grades,

wherein the addition amounts of the foaming agent, the catalyst and the stabilizer are respectively 5-20%, 0.5-10% and 0.1-5% of the mass of the polyether polyol.

Example 1

S1, after the polyurethane hard foam on the waste refrigerator is disassembled, cleaning and drying are carried out, and surface metal attachments are removed. 50 parts of cleaned waste polyurethane hard foam is put into crushing equipment, crushed waste polyurethane hard foam powder is sent into screening equipment through a conveyor belt, 1-2mm of powder is screened out, and other waste polyurethane hard foam powder with larger particles is put into the crushing equipment again for secondary crushing.

S2, cleaning the preheating kettle and the reaction kettle by using nitrogen. 25 parts of alcoholysis agent glycol is first preheated to 35 ℃ by a heated end of a condensing device, and then is second preheated to 78 ℃ by a preheating kettle. Placing the preheated alcoholysis agent and crushed waste polyurethane hard foam powder into a reaction kettle, adding 1 part of catalyst NaOH, opening electromagnetic heating equipment, heating to 130 ℃, stirring and dissolving for 1.5 hours, raising the temperature to 200 ℃ for reaction for 2 hours, standing for 2 hours, opening an oil outlet, discharging black oil, introducing the black oil into a sedimentation tank, standing for 2 hours, and obtaining pure degraded recovery products after a filtering device.

S3, feeding the filtered polyether polyol into a dealcoholization distillation kettle through a pipeline, dealcoholizing, and heating to 220 ℃ by using a supersonic frequency heater, wherein the polyol in the solution is changed into steam. The upper part of the reaction kettle is provided with a pipe outlet which is connected with a secondary condenser, the cooling temperature of the primary condenser is controlled to be 100 ℃ according to the boiling point of the polyol, part of organic waste gas becomes liquid, and the cooling temperature of the organic waste gas is controlled to be about 30 ℃ through the secondary condenser. The condensed organic liquid flows into a recovery tank; after the dealcoholization distillation reaction is finished, the recovered alcohol is recycled to the production of the next batch for use, and the recovered alcohol is directly used as a raw material without treatment.

S4, taking 20 parts of polyether polyol, sequentially adding foam stabilizer silicone oil L-6007.5 parts, catalyst organotin catalyst 0.5 parts and foaming agent HCFC-142b (dichlorofluoroethane) 15 parts, uniformly stirring, adding black diphenylmethane diisocyanate (MDI) 40 parts, rapidly stirring, and standing to naturally foam.

Example 2

S1, after the polyurethane soft foam on the waste sofa is disassembled, cleaning and drying are carried out, and surface metal attachments are removed. 50 parts of cleaned waste polyurethane soft foam is put into crushing equipment, crushed waste polyurethane soft foam powder is sent into screening equipment through a conveyor belt, 1-2mm of powder is screened out, and other waste polyurethane soft foam powder with larger particles is put into the crushing equipment again for secondary crushing.

S2, cleaning the preheating kettle and the reaction kettle by using nitrogen. 25 parts of alcoholysis agent 1, 3-butanediol is preheated to 40 ℃ for the first time through a heated end of a condensing device, and then preheated to 80 ℃ for the second time through a preheating kettle. Placing preheated alcoholysis agent and crushed waste polyurethane soft foam powder into a reaction kettle, adding 20 parts of auxiliary alcoholysis agent cyclohexylamine and 1 part of catalyst KOH, opening electromagnetic heating equipment, heating to 150 ℃, stirring and dissolving for 2 hours, heating to 180 ℃ for reacting for 2.5 hours, standing for 2.5 hours, opening an oil outlet, discharging black oil, introducing into a sedimentation tank, standing for 2 hours, and obtaining pure degraded recovered products through a filtering device.

S3, feeding the filtered polyether polyol into a dealcoholization distillation kettle through a pipeline, dealcoholizing, and heating to 220 ℃ by using a supersonic frequency heater, wherein the polyol in the solution is changed into steam. The upper part of the reaction kettle is provided with a pipe outlet which is connected with a secondary condenser, the cooling temperature of the primary condenser is controlled to be 110 ℃ according to the boiling point of the polyol, part of organic waste gas becomes liquid, and the cooling temperature of the organic waste gas is controlled to be about 35 ℃ through the secondary condenser. The condensed organic liquid flows into a recovery tank; after the dealcoholization distillation reaction is finished, the recovered alcohol is recycled to the production of the next batch for use, and the recovered alcohol is directly used as a raw material without treatment.

S4, taking 20 parts of polyether polyol, sequentially adding foam stabilizer silicone oil L-6007.5 parts, catalyst organotin catalyst 0.5 parts and foaming agent HCFC-142b (dichlorofluoroethane) 15 parts, uniformly stirring, adding black diphenylmethane diisocyanate (MDI) 40 parts, rapidly stirring, and standing to naturally foam.

Example 3

S1, after the polyurethane hard foam on the waste automobile is disassembled, cleaning and drying are carried out, and surface metal attachments are removed. 50 parts of cleaned waste polyurethane hard foam is put into crushing equipment, crushed waste polyurethane hard foam powder is sent into screening equipment through a conveyor belt, 1-2mm of powder is screened out, and other waste polyurethane hard foam powder with larger particles is put into the crushing equipment again for secondary crushing.

S2, cleaning the preheating kettle and the reaction kettle by using nitrogen. 25 parts of alcoholysis agent glycerin are first preheated to 38 ℃ by a heated end of a condensing device, and then are second preheated to 75 ℃ by a preheating kettle. Placing preheated alcoholysis agent and crushed waste polyurethane hard foam powder into a reaction kettle, adding 20 parts of alcoholysis assisting agent N, N-diethyl ethanolamine and 1 part of catalyst KOH, opening electromagnetic heating equipment, heating to 145 ℃, stirring and dissolving for 2 hours, heating to 185 ℃ for reaction for 3 hours, standing for 2.5 hours, opening an oil outlet, discharging black oil, introducing into a sedimentation tank, standing for 2 hours, and obtaining pure degraded recovered products through a filtering device.

S3, feeding the filtered polyether polyol into a dealcoholization distillation kettle through a pipeline, dealcoholizing, and heating to 220 ℃ by using a supersonic frequency heater, wherein the polyol in the solution is changed into steam. The upper part of the reaction kettle is provided with a pipe outlet which is connected with a secondary condenser, the cooling temperature of the primary condenser is controlled to be 105 ℃ according to the boiling point of the polyol, part of organic waste gas becomes liquid, and the cooling temperature of the organic waste gas is controlled to be about 33 ℃ through the secondary condenser. The condensed organic liquid flows into a recovery tank; after the dealcoholization distillation reaction is finished, the recovered alcohol is recycled to the production of the next batch for use, and the recovered alcohol is directly used as a raw material without treatment.

S4, taking 20 parts of polyether polyol, sequentially adding foam stabilizer silicone oil L-6007.5 parts, catalyst organotin catalyst 0.5 parts and foaming agent HCFC-22 (chlorodifluoromethane) 15 parts, uniformly stirring, adding black polyphenyl polymethylene polyisocyanate (PAPI) 40 parts, rapidly stirring, and standing to naturally foam.

Example 4

S1, after the polyurethane hard foam on the waste building is disassembled, cleaning and drying are carried out, and surface metal attachments are removed. 50 parts of cleaned waste polyurethane hard foam is put into crushing equipment, crushed waste polyurethane hard foam powder is sent into screening equipment through a conveyor belt, 1-2mm of powder is screened out, and other waste polyurethane hard foam powder with larger particles is put into the crushing equipment again for secondary crushing.

S2, cleaning the preheating kettle and the reaction kettle by using nitrogen. 25 parts of alcoholysis agent glycol is first preheated to 35 ℃ by a heated end of a condensing device, and then is second preheated to 70 ℃ by a preheating kettle. Placing preheated alcoholysis agent and crushed waste polyurethane hard foam powder into a reaction kettle, adding 20 parts of alcoholysis assisting agent diisopropanolamine and 1 part of catalyst KOH, opening electromagnetic heating equipment, heating to 120 ℃, stirring and dissolving for 2 hours, heating to 190 ℃ for reaction for 3 hours, standing for 2.5 hours, opening an oil outlet, discharging black oil, introducing into a sedimentation tank, standing for 2 hours, and obtaining pure degraded recovered products through a filtering device.

S3, feeding the filtered polyether polyol into a dealcoholization distillation kettle through a pipeline, dealcoholizing, and heating to 220 ℃ by using a supersonic frequency heater, wherein the polyol in the solution is changed into steam. The upper part of the reaction kettle is provided with a pipe outlet which is connected with a secondary condenser, the cooling temperature of the primary condenser is controlled to be 120 ℃ according to the boiling point of the polyol, part of organic waste gas becomes liquid, and the cooling temperature of the organic waste gas is controlled to be about 38 ℃ through the secondary condenser. The condensed organic liquid flows into a recovery tank; after the dealcoholization distillation reaction is finished, the recovered alcohol is recycled to the production of the next batch for use, and the recovered alcohol is directly used as a raw material without treatment.

S4, taking 20 parts of polyether polyol, sequentially adding foam stabilizer silicone oil L-6007.5 parts, catalyst organotin catalyst 0.5 parts and foaming agent HCFC-142b (dichlorofluoroethane) 15 parts, uniformly stirring, adding black diphenylmethane diisocyanate (MDI) 40 parts, rapidly stirring, and standing to naturally foam.

Example 5

S1, after the polyurethane hard foam on the waste pipeline is disassembled, cleaning and drying are carried out, and surface metal attachments are removed. 50 parts of cleaned waste polyurethane hard foam is put into crushing equipment, crushed waste polyurethane hard foam powder is sent into screening equipment through a conveyor belt, 1-2mm of powder is screened out, and other waste polyurethane hard foam powder with larger particles is put into the crushing equipment again for secondary crushing.

S2, cleaning the preheating kettle and the reaction kettle by using nitrogen. 25 parts of alcoholysis agent glycol is first preheated to 35 ℃ by a heated end of a condensing device, and then is second preheated to 80 ℃ by a preheating kettle. Placing preheated alcoholysis agent and crushed waste polyurethane hard foam powder into a reaction kettle, adding 20 parts of alcoholysis assisting agent diisopropanolamine and 1 part of catalyst NaOH, opening electromagnetic heating equipment, heating to 125 ℃, stirring and dissolving for 2 hours, heating to 195 ℃ for reaction for 3 hours, standing for 2.5 hours, opening an oil outlet, discharging black oil, introducing into a sedimentation tank, standing for 2 hours, and obtaining pure degraded recovered products after a filtering device.

S3, feeding the filtered polyether polyol into a dealcoholization distillation kettle through a pipeline, dealcoholizing, and heating to 220 ℃ by using a supersonic frequency heater, wherein the polyol in the solution is changed into steam. The upper part of the reaction kettle is provided with a pipe outlet which is connected with a secondary condenser, the cooling temperature of the primary condenser is controlled to be 120 ℃ according to the boiling point of the polyol, part of organic waste gas becomes liquid, and the cooling temperature of the organic waste gas is controlled to be about 40 ℃ through the secondary condenser. The condensed organic liquid flows into a recovery tank; after the dealcoholization distillation reaction is finished, the recovered alcohol is recycled to the production of the next batch for use, and the recovered alcohol is directly used as a raw material without treatment.

S4, taking 20 parts of polyether polyol, sequentially adding foam stabilizer silicone oil L-6007.5 parts, catalyst organotin catalyst 0.5 parts and foaming agent HCFC-142b (dichlorofluoroethane) 15 parts, uniformly stirring, adding black diphenylmethane diisocyanate (MDI) 40 parts, rapidly stirring, and standing to naturally foam.

The polyol storage tank is connected with the heated end of the condensing equipment through a feed pump 1 and a pipeline, and is used for carrying out primary preheating on the polyol raw material, and then enters a preheating kettle for carrying out secondary preheating. Meanwhile, the waste polyurethane hard foam/soft foam is added into a funnel in a manual mode, dust is prevented from being diffused when the dust-proof airtight cover is covered, crushed waste polyurethane powder is sent into screening equipment through a conveyor belt, and the screen mesh is utilized to screen the waste polyurethane foam which is not crushed completely. Meanwhile, adding the polyol and the waste polyurethane powder which are subjected to waste heat into a reaction kettle, adding an alcoholysis assisting agent, and heating to 100-180 ℃ through electromagnetic induction, wherein the following transesterification reaction occurs in the reaction kettle, and taking example 3 as an example, the degradation reaction mechanism is as follows:

after the reaction is carried out for 6 to 10 hours, standing is carried out for 2 to 3 hours, a rotating blade is opened for stirring, the stirring is carried out for fully stirring materials in a reaction kettle, an oil outlet is opened, unreacted and complete waste polyurethane powder and byproduct black oil floating on the upper layer are discharged for primary separation, a discharge port is opened, the rest polyether polyol is put into a sedimentation tank, standing is carried out for 2 to 3 hours, solids in the solution are subjected to secondary separation, and the separated polyether polyol solution is pumped into a filtering device to remove redundant waste gas and waste residues. And (3) pumping the finished polyether polyol into a dealcoholization still through a pipeline, purifying the product and recycling the polyol in the product. And adding a foaming agent, a catalyst and a stabilizer into the finished polyether polyol, uniformly stirring, adding black materials according to a certain proportion, rapidly stirring, and standing to naturally foam. The following reactions occur during foaming:

in the description of the present invention, it should be noted that, for convenience of description and simplification of the description, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. refer to the azimuth or the positional relationship based on the azimuth or the positional relationship shown in the drawings, and do not indicate or imply that the apparatus or element referred to must have a specific azimuth, be configured and operated in a specific azimuth, and therefore should not be construed as limiting the present invention; the terms "first," "second," "third," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance, and furthermore, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "coupled," and the like are to be construed broadly, and may be fixedly coupled, detachably coupled, or integrally coupled, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims (8)

1. A process system for polyurethane recovery, characterized by: the polyurethane recycling production line comprises a raw material area, a reaction area and a finished product area, wherein the reaction area is composed of crushing equipment, conveying equipment, screening equipment, a reaction kettle, condensing equipment, a raw material storage tank, a preheating kettle, a sedimentation tank, a filtering device and a dealcoholization distillation kettle, the crushing equipment is composed of a conical hopper, a dustproof sealing cover, crushing blades and a first engine, the conveying equipment is composed of a conveying belt and a second engine, the screening equipment comprises a third engine, an output shaft of the third engine is connected with the reaction kettle by a cylindrical mechanism.

2. A polyurethane recycling process system according to claim 1, wherein: the output shaft of the first engine is fixedly connected with the crushing blade, the crushing blade is arranged in the center of the conical funnel, and the conical funnel is connected with the transmission equipment.

3. A polyurethane recycling process system according to claim 1, wherein: the conveying equipment is placed at an inclination angle of 30 degrees, and the tail end of a conveying belt in the conveying equipment is connected with the screening equipment.

4. A polyurethane recycling process system according to claim 1, wherein: the inside is one deck screen cloth, outside in the cylinder structure is threaded form cylinder steel construction.

5. A polyurethane recycling process system according to claim 1, wherein: the reactor is characterized in that a feeding port is arranged at the top end of the reactor and is used for receiving broken and screened waste polyurethane powder and preheated polyol, condensing equipment is fixedly arranged at the top end of the reactor and is used for recycling polyol steam, electromagnetic heating equipment, an oil outlet, a water inlet and a discharging port are arranged in the reactor, the oil outlet is located on the middle wall surface of the reactor tank body, the discharging port is located at the bottom end of the reactor, the water inlet is connected with a hydraulic spraying device, the discharging port is connected with a sedimentation tank, and the other end of the sedimentation tank is connected with a filtering device.

6. A polyurethane recycling process system according to claim 1, wherein: the preheating kettle is internally heated by adopting a coil pipe, the coil pipe is internally heated by adopting heat conduction oil, and the heat source is electrically heated.

7. A polyurethane recycling process system according to claim 1, wherein: the filter device consists of a filter cake and an active carbon filter device, and the filter device is connected with the dealcoholization still.

8. A process for the recovery of a polyurethane as claimed in any one of claims 1 to 7, comprising the following operative steps;

s1, filling the waste polyurethane material into a conical hopper of crushing equipment in an artificial mode, and crushing the waste polyurethane material by a crushing blade after electrifying, wherein the waste polyurethane material is sourced from a waste refrigerator, a building heat preservation layer, a helmet, a waste motorcycle, a waste automobile, a sofa and industrial equipment.

S2, conveying the crushed waste polyurethane powder to screening equipment through a conveyor belt, separating the large waste polyurethane foam from the small waste polyurethane powder through a screen, taking the large waste polyurethane foam out of the screen, recharging the large waste polyurethane foam into a hopper of the crushing equipment, and crushing again.

S3, conveying the crushed waste polyurethane fine powder into a reaction kettle through a feed inlet at the top end of the reaction kettle for alcoholysis reaction.

S4, firstly sending the polyol raw material into condensing equipment at the top end of the reaction kettle through a feed pump 1 to perform primary preheating to preheat the polyol to 25-50 ℃, simultaneously recovering polyol steam incompletely reacted through the condensing equipment, and re-pumping the condensed and recovered liquid polyol into the reaction kettle.

S5, pumping the first-stage preheated polyol solution into a preheating kettle, and carrying out secondary heating on the polyol in a coil heating mode to 50-80 ℃.

S6, adding crushed waste polyurethane powder and preheated polyol into a reaction kettle, adding an alcoholysis assisting agent, and heating to 100-180 ℃ in an electromagnetic induction heating mode.

S7, opening an oil outlet of the reaction kettle, flowing out unreacted black oil which is completely and partially floating, performing primary separation, introducing polyether polyol after alcoholysis reaction into a sedimentation tank, performing physical sedimentation for 6-8 hours, removing unreacted waste polyurethane powder and fine solids, and performing secondary separation.

And S8, the settled polyether polyol passes through a filtering device, primary filtering is carried out on a filter cake, and then secondary filtering and adsorption are carried out through an active carbon device, so that the finished polyether polyol is obtained.

And S9, feeding the filtered polyether polyol into a dealcoholization distillation kettle through a pipeline, dealcoholizing, and heating to 220 ℃ by using a superaudio heater, wherein the polyol in the solution is changed into steam.

S10, arranging a pipe outlet above the reaction kettle, connecting a secondary condenser, controlling the cooling temperature of the primary condenser to be 100-120 ℃ according to the boiling point of the polyol, enabling part of organic waste gas to become liquid, and controlling the cooling temperature of part of organic waste gas to be about 30-40 ℃ through the secondary condenser.

S11, flowing the condensed organic matter liquid into a recovery tank; after the dealcoholization distillation reaction is finished, the recovered alcohol is recycled to the production of the next batch for use, and the recovered alcohol is directly used as a raw material without treatment.

S12, taking a certain amount of polyether polyol, sequentially adding a foam stabilizer, a catalyst and a foaming agent, uniformly stirring, adding black materials according to a certain proportion, rapidly stirring, standing to naturally foam,

wherein the addition amounts of the foaming agent, the catalyst and the stabilizer are respectively 5-20%, 0.5-10% and 0.1-5% of the mass of the polyether polyol.