KR20100061788A - Selective multistage catalytic pyrolysis process for the recycled oil recovery from polymers - Google Patents

Abstract

PURPOSE: A selective multi-stage catalytic pyrolysis method is provided, which can collect a high-boiling point waxes as reconstituted oil by re-decomposing the high-boiling point waxes in the final step of stationary phase disassemble again. CONSTITUTION: A selective multi-stage catalytic pyrolysis method of a continuous system of polymer compound includes the steps: a step of collecting heat with pyrolysis heating source after the resin which has the low decomposition temperature is selectively pyrolyzed under 300 deg.C, and then the hydrochloride which is formed is washed in the washing tower to be neutralized, after that, the decomposition gas is burnt in the gas burner; a step of collecting continuously the refined reconstituted oil through the collection side of the column side after the thermoplastic resin is pyrolyzed by using the melted residue polymer, and then, the carbide production is minimized; and a step of collecting the reconstituted oil of the high quality by using the high-boiling point waxes.

Description

Selective multistage catalytic pyrolysis process for recovering regenerated oil from high molecular compounds. {Selective Multistage Catalytic Pyrolysis Process for the Recycled Oil Recovery from Polymers}

The technical field of the present invention is a thermal decomposition method of a polymer compound, the thermal decomposition method is an aliphatic high molecular compound such as vinyl chloride resin (PVC), polyether (PE), polypropylene (PP), and polyether terephthalate ( PET), polystyrene (PS), and a mixture of aromatic polymer compounds such as acryronitrile butadiene styrene (ABS) resins are heated to high temperature without contact with oxygen, without being screened, and decomposed into low molecular hydrocarbons. It is an economical and high value-added process that can be recovered.

Patent application No. 116586 of the present invention is an unstirred thin film pyrolysis device in which a fixed bed pyrolysis catalyst is filled in a tube. As a result, only the liquid thermoplastic resin can be reacted, and the solid matter may be deposited on the surface of the catalyst and the fixed phase may be blocked. Thereby, there is a limitation that the thermosetting resin cannot be treated by filtration.

        Patent application 40640 has developed a method suitable for the thermal decomposition of waste synthetic resin by improving the air flow transfer pyrolysis technique, which is a known pyrolysis method, for catalytic pyrolysis of solids that cannot be treated in the present invention. The reaction stage is divided into one-stage falling pyrolysis and two-stage falling pyrolysis, and in the first-stage falling pyrolysis step, firstly pyrolyzes the thermoplastic resin melted by high heat in the mixed waste synthetic resin input to produce fuel oil mainly composed of kerosene. In the fall-fall pyrolysis step, a high-temperature catalyst is added to the reactor to increase the temperature, and thermally decompose the powdery thermosetting resin, which has not reacted in the previous stage, to generate cracked gas, which is a low molecular hydrocarbon, to form a liquid and powdery waste synthetic resin in a single reaction system. It is effective pyrolysis within.

    Conventionally known air flow pyrolysis methods continuously inject liquid or powdered waste synthetic resin into a vertical tubular air flow pyrolysis reactor which circulates the regenerated high temperature regenerated catalyst together with the reaction gas or the inert gas, thereby regenerating the high temperature regeneration catalyst and the raw material resin. Is a reaction apparatus that promotes catalytic pyrolysis by direct contact with heat transfer, and there are two methods of air transfer pyrolysis reactors, a rising type and a falling type, but the reaction time is very short as several seconds, so that the pyrolysis temperature and conditions vary. It is difficult to pyrolyze the mixed synthetic resin as a single reaction step. U.S. Patent No. 6,534,689 intends to complete the reaction by performing fluidized bed pyrolysis again in the bottom water of the falling air stream pyrolysis unit as a complementary solution. However, in order to form a fluidized bed, a reaction gas or an inert gas needs to be blown to the lower part of the fluidized bed, which impedes practicality by impeding the recovery of generated hydrocarbons or removing hydrogen chloride gas.

Pyrolysis is a sensitive catalytic reaction in which high-temperature flammable vapors are generated. In addition, the pyrolysis reaction temperature exceeds the ignition point of low molecular hydrocarbons, and the pyrolysis reaction apparatus has a high risk of ignition and ignition. Due to the deterioration of the activity due to excessive generation of cracked gas and tar phase carbide, mechanical fragility of the device and a high degree of difficulty operation technique was not practical. In addition, vinyl chloride resin (PVC) is contained in the life-cycle mixed synthetic resin, which accounts for half of the amount of plastics produced, and this material contaminates the decomposition gas generated by releasing a large amount of corrosive gas, hydrogen chloride, during decomposition. As a result, it is a factor that hinders the recycling of recovered recycled oil. In addition, due to the inability to recycle cracked gas, energy efficiency was low, falling short of the break-even point, resulting in economic deterioration.

The present invention prevents the influx of fire by fundamentally preventing the inflow of oxygen by passing the nitrogen sealing chamber when the raw material is fed into the automatic feeder, and to prevent contamination of the regenerated oil, the vinyl chloride resin and the polystyrene in the first stage melter. It selectively decomposes resins with low decomposition temperature such as resins, discharges hydrogen chloride as a product, neutralizes them in the washing tower, burns the purified decomposition gas with a gas burner, and uses it as a heat source for pyrolysis to improve energy efficiency. The thermoplastic resins, such as polyolefins melted in the melter and undigested polyolefin, are continuously introduced into the two-stage fluidized bed cracker to rapidly pyrolyze on the preheated catalyst, thereby minimizing the generation of tar and carbides, and producing the cracked steam in a consistent process. Continuously introduced into the fractionation column, the packed bed in the tower As the vapor rises, low boiling point and wax are separated continuously, and purified high-quality recycled oil without chlorine contamination is continuously recovered through the side of the distillation column, and finally falls to the top of the fixed bed cracker under the distillation column. The high boiling point waxes are re-decomposed on the catalyst to raise the regenerated oil converted into the low molecular weight through the packed bed to recover the high quality regenerated oil through the recovery valve in high yield.

 1) By practically recovering recycled oil from mixed synthetic resin containing vinyl chloride resin, it is possible to recycle waste synthetic resin of about 3 million tons / year as alternative energy without end-processing to achieve environmental protection and crude oil import substitution effect. ..

2) Vinyl chloride resin is one of the four general-purpose resins, so that hydrogen chloride and recycled oil are separated and recovered economically by selective multi-stage catalytic pyrolysis method, thereby achieving practical use of waste vinyl chloride resin.

 1 is a process diagram of a continuous selective multistage catalytic pyrolysis method for recovering regenerated oil from a polymer compound.

If described in detail by the accompanying drawings;

 (101) Compression-packed mixed synthetic resin fed into an automatic feeder is continuously supplied to a melter through a sealed chamber filled with nitrogen (102) and melted, and hydrogen chloride produced by thermal decomposition of partially pyrolyzed decomposition gas and vinyl chloride resin is steamed. It is quenched by the circulating washing water and neutralized with caustic soda through (108) through the washing tower, and unresolved molten resin remaining in the melter is continuously introduced into the (103) fluidized-phase cracker and contacted with the preheated catalyst. The resulting cracked steam, which is not contaminated with chlorine, is introduced into the (104) fractionation column continuously in a consistent process and ascends to the column through the packed bed and is repeatedly fractionated by condensation and vaporization by reflux from the column. Distillation causes cracked gas and low boiling point to rise to the top and high boiling wax drops to the bottom of the column. Cooling through the outlet was 106 cooler through the waterside is stored is introduced into 107 oil bath playback. Wax descending to the bottom of the fractional distillation column is introduced into the (105) stationary bed cracker, re-decomposes on a catalyst, is converted into low molecules, and is raised through a packed bed to be recovered through a reclaimed oil recovery valve. The decomposed residues remaining in the fluidized bed cracker are mixed with the deactivated waste catalyst and continuously discharged to the side outlet. The cracked gas and the low boiling fraction are discharged to the tower top, condensed and refluxed through the condenser, and the uncondensed cracked gas is purified through the washing tower (108), flowed into the gas storage tank (109) and supplied to the gas combustor, and burned. It is used as a pyrolysis heat source to heat recovery to improve energy efficiency.

The code | symbol of each apparatus of the process diagram of FIG. 1 is as follows;
(101) Automatic Input Machine (106) Cooler
(102) Melter (107) Regeneration Tank
(103) Fluidized Bed Crackers (108) Cleaning Towers
(104) Fractionation distillation tower (109) Gas tank
(105) Stationary phase crackers (110) Gas burners

Claims (1)

In order to completely prevent the influx of oxygen through the nitrogen sealing chamber and to inject the polymer compound through the automatic feeding machine continuously, it is possible to fundamentally prevent fire factors, and to selectively catalytically decompose vinyl chloride resin, thermoplastic resin and wax at each stage. ,
A) In one step, hydrogen chloride produced by selectively pyrolyzing resins with low decomposition temperatures such as vinyl chloride resin and polystyrene resin at less than 300 degrees Celsius is neutralized and cleaned in a washing tower, and the decomposition gas is pyrolyzed by burning in a gas combustor. Heat recovery with heat source,
B) Minimize the formation of carbides by rapid thermal decomposition of thermoplastic resins such as polyolefins through direct contact with catalyst preheated below 700 degrees Celsius by continuously injecting residual polymer compound which is not decomposed in the melter into the fluidized bed decomposer. And continuously introduced into the fractionation tower by a consistent process to recover the high-quality refined regenerated oil with chlorine contamination, low boiling point and wax removed through the top side recovery valve,
C) High boiling point waxes falling into the fixed bed cracker at the bottom of the fractional distillation column in three stages are continuously re-decomposed on the catalyst at below 500 degrees Celsius, converted to low molecular weight, raised through the packed bed, and recycled with high yield through high recovery yield. To recover oil,
Continuous selective multistage catalytic pyrolysis of polymer compounds characterized by selective pyrolysis and nitrogen sealing and cracked gas heat recovery as described above.

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