DE2132537A1 - Solid waste treatment process - Google Patents

Description

DIPL.-INQ. GÜNTHER EISENführer

DIPL.-ING. DIETER K. SPEISER 2132537

PATE NTAN CHOICES

File number: New registration 28 BREMENI

BORQERMEISTER-SMIDT-STR. Registration name: OCCIDENTAL PETROLEUM CORPORATION (Trinidad House)

TELEPHONE: «M21) J13t77 TELEGRAMS: FEHROPAT

BREMER BANK 100 9072 POST CHECK HAMBURG 255767 US. CHARACTER: 0 11

Date: June 29, 1971

OCCIDENTAL PETROLEUM CORPORATION, incorporated under the laws of the State of California, Los Angeles . California (V. St. A.)

Solid waste treatment process

The invention relates to a method for processing solid waste, in particular a method for comminuting and separating the organic components from the metallic - inorganic components of the waste, as well as their processing for recovery.

Every day, steadily growing considerable amounts of solid waste are generated, their removal, disposal and Harassment is a significant problem. The costs of waste disposal are in third place expenses for schools, highways and general municipal expenses. The amount of garbage that accumulates in large cities every day really surpasses anyone's imagination. It is estimated that about 2 to 3 kg of garbage accumulate daily. The industrial waste corresponds to an additional 3 to 5 kg per person and Day. The average cost of waste disposal is around 20 to 40 DM / t.

109884/1174

Conventional methods of waste disposal, such as; dumping garbage in garbage pits or incineration are becoming more and more expensive or create serious ones Pollution problems. Purely garbage dumps suitable areas e.g. are becoming increasingly rare and are further away from the communities in which the waste is generated.

Waste incineration is growing in places where it is not already banned because of air pollution Viewed with skepticism. Furthermore, solid residues are still produced in the incineration process, which on some Kind of need to be eliminated.

Another aspect of waste disposal is that conventional waste disposal processes are an ongoing process Result in loss of raw materials. Every nation is consuming its raw materials to an ever increasing extent. Many reserves of rare minerals and metals have a finite lifespan. Inexhaustible itself Apparent consumer goods, such as paper, are unlikely to be in demand in the coming years produce satisfactory quantities. And yet, through garbage disposal, the raw material sources become continued through garbage disposal, constantly exhausted.

The object of the invention is to propose a method by means of which the solid waste is processed in this way let their valuable constituents economically recovered and their organic residues transformed into usable chemicals and fuel products.

This object is achieved by a method that results in a crushing of the solid waste in an easier way processable mass, a separation of the crushed mass into an organic component and a metal

109884/1174

lisch-inorganic component through air and / or water precipitation, a processing of the organic component for the recovery of paper pulp and a pyrolysis of organic residues to generate a gas stream containing chemicals and solid as fuel suitable coke.

Magnetic ferrous materials become magnetic either from the unseparated crushed waste or from the metal-inorganic constituents according to Separation separated. The metal-inorganic components free from ferrous materials are then broken down into fractions of the same density by a controlled separation of heavy materials. The factions the same Density is then achieved through heavy material separations, floating separations and particle size separations as well as other mineral processing techniques into their usable Components disassembled.

This process turns most of the constituent parts of the waste into resalable and recyclable ones Scrap metal groups, glass and paper pulp are separated and the residues are converted into usable chemicals and fuel reshaped. The sale of these recyclable materials largely covers the cost of the process or leads to a profit. In addition, however, it is far more important that scarce raw materials are recovered.

The invention is described in detail below with reference to the embodiments shown in the drawings. It shows:

1 shows a basic circuit diagram of an embodiment of a a method according to the invention for processing solid waste;

109884/1174

Pig. 2 shows a basic circuit diagram of a further embodiment of a processing method according to the invention solid waste;

3 shows a detailed circuit diagram of the method according to the invention for processing metallic-inorganic components of solid waste;

Pig. 4 shows a detailed circuit diagram of the method according to the invention for pyrolysis of organic constituents solid waste.

A method according to the invention for processing solid waste essentially consists of the following steps: Shredding of solid waste into sizes suitable for further processing, dismantling of solid waste by air and / or water precipitation into an organic fraction and a metallic-inorganic fraction, recovery of paper pulp from the organic fraction and pyrolysis of the organic residues for production a gas stream, reusable chemicals, and solids that can be used as fuel or carbon Contains coke. The metal-inorganic fraction is then used to recover its various Metal and glass components dismantled.

In this basic framework, the invention can Processing of solid waste depending on the device used and the type of waste to be processed solid waste vary in manifold ways.

The "crushing" can be done e.g. in any technique for Reduction in physical size exist; it can e.g., but not exclusively, in one chopping, breaking, tearing, chopping or grinding by suitable machines.

109884 / 117A

According to FIG. 1, in a preferred method according to the invention, solid waste is fed to a first shredder 10 supplied, which is shown as a cross beater mill and a first loosening or slight size reduction of the garbage. The outflow of the shredder 10 is then brought into contact with a gas flow, preferably a hot flue gas flow supplied by another part of the process, which dries the shredded waste so that most of the paper present is collected in a collecting chamber 12 by gas flow separation leaves. In this procedure the degree of comminution of the cross beater mill 10 is generally kept as small as possible, so that as possible a lot of paper can collect in the collecting chamber 12. The paper gathered in this way is relatively free from pollution; it can therefore be easily dissolved in a paper stock tank 14. Those materials that does not expand to the size of the paper in the paper tank 14 can be solved by a cyclone or a sieve 16 or the like. removed from the paper pulp and fed to a second paper pulp tank 18 or other equipment, e.g. an apparatus for separating plastics by density differences. The dissolved pulp then becomes one Cleaning container 20 supplied, in which it is washed and cleaned. Then it goes through a dewatering stage 22, which it as a sellable paper pulp or for bleaching known from conventional waste paper processing techniques. Impurities separated from the cleaning tank 20 become the second Paper stock tank 10 supplied.

Solid constituents that the hot gas stream does not get into the Paper collecting chamber 12 are carried, become a «Wide shredder 24 shown as a cross beater mill for further size reduction are fed and passed then in a centrifugal force separator 26, in which a

109884/1174

Separation takes place according to density differences.

The particles then pass through a flood separator 28 or the like, in which the organic tractions are excreted, their effective density less than or equal to the density of the upstream water or which is light enough are to be carried up by the current. The rest of the pulp or pulp-like materials containing organic fraction is together with the impure pulp fractions from the sieve 16 and ) from the cleaning container 20 for further dissolution Paper stock tank 18 supplied. After the dissolution, the pulp is centrifuged and passed through a sieve machine 30 supplied for the separation of coarse particles. The paper pulp is then fed to a second cleaning container 32, which it is for sale or for further use Processing or for return to the paper stock tank 14 for renewed separation and processing with leaves the dry separated paper pulp.

The organic residues including all unwanted paper pulp are dewatered in a dewatering unit 34 and fed, with or without prior drying, to a multistage pyrolysis furnace 36 by converting them into a gas stream containing recyclable chemicals and solid carbon Use a rotary kiln or another carbonating device If, with this alternative, the majority of the waste paper is blown out of the envelope by the hot gas separation , the organic fraction can be fed from the separator 28 via the sieve 34 to the pyrolysis furnace 36, or the dry, solid waste are fed directly to the pyrolysis furnace 36.

The elutriation of the separator 28 runs over a sieve 38, thus fine and muddy materials of the waste

10 9 8 8 4/1174

separated from the metal-inorganic fraction. This fraction then passes through a magnetic separator 40, the magnetic iron material for further processing removed as scrap iron from the metallic-inorganic fraction.

They will be residual metals and inorganics then fed to a heavy material separator 42, in which inorganic substances and metals of the same density or metals, e.g. magnesium, the density of which is lower than those of the inorganics accumulate at the top while the heavier metals settle to the bottom. In the Heavy material separation can be the effective specific Medium density exactly through the addition of iron oxide or the like. to adjust to water. At a given effective specific gravity, substances swim with a lower specific density, while substances decrease with a higher specific density.

The fraction that is on the heavy material separator 42 collects, is then fed to a sifter 44 in which crushed glass and aluminum are differentiated separated in particle size from sand, dirt, etc.

In a separate grinding and sieving unit 46, glass can then be separated from aluminum through different particle sizes separate. If the particles are largely of the same size, the size required for a sieve separation can be used Difference in size of the particles using a ball mill or the like. generate in the aluminum and magnesium particles further rolled out and glass particles further crushed. The reclaimed glass can be then for the production of bottles or the like. Selling.

Alternatively, if magnesium is present, it can be 109884 / 1m

by a heavy material separation from the inorganic Separate fabrics and / or aluminum.

The heavy metal fraction, which is obtained as a set in the heavy material separator 42, can be in one or more Divide heavy material separators 48 further, in which the heavier metals through a sink-swim separation separated from the lighter metals. In the process shown, the light metals pass through k after their separation from the heavy metals, a sieving machine 50, which removes light metal dust.

Alternatively, melt, dissolve or flood techniques can be used used to further separate the individual parts of the heavy metal fraction into groups of relatively pure metals To subject processing and cleaning to a Peinseparation.

The sludge from the various separation operations is fed to a thickener 52 in which the process water is recovered while the remaining solids are fed to a cyclone 54. The cyclone 54 separates inorganic materials in order to return them to the heavy material separation system.

If the process water becomes enriched with soluble impurities in the course of time, it must either be discarded or recycled by evaporation for reuse.

Pig. Figure 2 shows an alternative solid waste recycling process that has certain regional advantages owns. For example, there is a good market for tinned cans in some areas of the United States. It it is important to keep the tinned bushings as undamaged as possible.

109884/1174

Digt to regain, so that all organic deposits are effectively removed and the cans are tinned and used Use in the copper industry can be cut up. Furthermore, due to the premature separation removes large amounts of ferrous materials from solid waste that would otherwise pollute the mills and would increase the cost of materials.

In the preparation process according to Pig. 2, the solid waste is poured into a funnel 56 and then conveyed by a conveyor belt 58 to a loosener or crusher 60, which acts as a cross beater mill is shown and performs a first loosening of the waste. After that, the garbage is put in a magnetic separator 62, e.g. fed to a magnetic belt that separates tin cans and other ferrous materials from the non-magnetic materials. The non-magnetic Materials are fed to a dry or wet separator and possibly also to some shredders. The tin cans and other ferrous materials are then fed to a processing system, largely without being crushed, which effectively removes the organic components removed, tinned the cans and cut up for processing in the copper industry. In the separator 64 the inorganic materials and the non-ferrous metals settle on the ground, while the organic materials withdrawn at the top and fed to a chopping machine 66.

Since only a coarse comminution has taken place in the cross beater mill 60, there is a further comminution required, i.e. the waste paper must be shredded, thus a good fiber separation and a good paper recovery from the solid organic matter in the fiber separator 68 is achieved. After the separation of the paper pulp, the remaining organic matter

109884/1 174

materials including coarse fibers from the fiber separator 68 supplied from the pyrolysis furnace 56.

The inorganic non-ferrous metal fraction is then fed to a heavy material separator 70, in which a separation of inorganic substances and light metals, e.g. magnesium and aluminum of the heavier metals, e.g. copper and stainless steel. The inorganic substances and the light metals are then put in a heavy material separator 72 supplied, in which the inorganic substances and aluminum are separated from magnesium, -das is deducted at the top. Then the inorganic substances are separated from the aluminum by floating or sieving, e.g. in a sieving machine 74, in the size differences the article can be used for separation instead.

Figure 3 shows a particularly for the separation of the iron-free metallic-inorganic fraction particularly suitable system. The of ferrous substances by a magnetic Separation and heavy fraction of the waste freed from organic substances by flood separation is fed to a coarse screening machine. Since only a slight size reduction, e.g. in the cross beater mill 2, the particles of the metals and the inorganic substances are still relatively large, so that a first segregation can be carried out due to differences in size. The screening machine 76 has a screen of relatively large hole size of about 25 mm, through which smaller objects normally fall, e.g. Jewelery, precious stones or the like. These items pass a Fettisch 78 on which all gemstones including their gold frames stick to a hand selection. Those materials that are not through the The sieve of the sieving machine 76 will fall into a

10 9 8 8 4/1174

Schnitzel machine 80 and together with the Materials running off from the fat table 78 are fed to a Peinsiebmaschine 82 with a sieve hole size of less than 25 mm. The fine material running off the screening machine 82 is fed to a settling container 84. The coarse material will a heavy material separator 86 fed, in which the heavy metals, which settle on the bottom, from the inorganic Materials and light metals are separated.

All f-erritic residues in the light fraction are deposited in a magnetic separator 88. Of the The remainder is fed to a ball mill 90. In the ball mill 90 is between the inorganic substances and the aluminum and magnesium alloys created a difference in particle size, since the soft aluminum and magnesium alloys are rolled out, so that their particle size increases, while glass or the like. is crushed so that its particle size decreases.

The rolled metals and crushed inorganics are then fed to a screening machine 92. The aluminum and magnesium metals stay on the sieve, while the inorganic substances pass through the Sieve in a flushing unit 94 or the like. fall. In the flushing unit 94 are glass and sand, which are for the Glass making are usable, from bricks, ceramic materials and concrete residues that are discarded be separated. Glass and sand are then fed to a high intensity magnetic separator 96 in which due to Because of its iron content, colored glass is separated from clear glass.

Those settling on the bottom of the heavy material separator 86 Heavy metals are a fine sieve machine 98 (with

109884/1174

a sieve hole size of approximately 65 mesh), in which a separation of the metal is carried out from the separation medium, which is separated again into the heavy material or 86 is returned. The metals separated in the screening machine 98 are subjected to a coin separation system 100 supplied, in which coins or the like in a type case. accumulate. Then the coins are made by hand separated from metal objects of the same size.

The heavy metals are then fed to a suitable processing system. For example, you can initially pass an ammonia liquor tank 102 in which metals such as copper, nickel, cobalt and zinc are separated from stainless steel and all iron residues. The stainless steel and the iron residues are then mixed with the iron alloys separated earlier in the process merged. The leached metals are then fed to a solution separator 104, in the primary and / or secondary amines can be used to separate copper from the remainder of the leached metals. That Copper is then used in a stripper 106 and an electrolysis unit 108 recovered. Zinc, nickel and cobaite that have been separated from the copper Then precipitation separators 110 are supplied, in which they are converted into carbonate salts by the addition of carbon dioxide will. The remaining liquid is returned to the ammonia liquor tank 102.

The 'running off the screening machine 98 liquid together with the heavy medium particles contained in it fed to the heavy material separator 84, in which it continues is used. The dirty drainage water is an evaporator (not shown) to recover the water and separate the solid residues from Settling container 84 supplied.

109884/1174

The set of the set container 84 can be various Materials such as molybdenum, thungsten, silver or the like, contain; If desired, these can be filtered out in a filter 112 and the residual sludge either in the pyrolysis oven fed or discarded.

Pig. 4 shows in detail a pyrolysis system for forming the organic fraction in chemicals and fuels. Pyrolysis are comminution, Separation, kneading and preliminary dewatering operations are upstream in order to create one for the Feeding into the pyrolysis system to obtain suitable organic fraction. While the organic fraction can be fed directly into a pyrolysis furnace with or without the addition of fuel, e.g. Kphle, it becomes preferably in a dryer 114 in cocurrent or countercurrent with hot flue gases from a pyrolysis furnace 116 brought into contact. Water and organic matter evaporated during drying deposited in a condenser 120 and fed to a phase separator 122, the oil and other organic Separates components of low density from the condensate. Uncondensed organic matter and all hydrates are fed to a hydrogenation column 124 for conversion into a high quality oil. Alternatively can flue gas can also be used for direct or indirect drying. With dry pulp or with small systems no drying is required.

The dryer 114 leaving organics are a first Hochgeschwindigkelts pyrolysis furnace supplied 126 with low particle density in which they are mixed with a carbonaceous fuel, such as coal dust or hot coke and under non-oxidizing conditions at temperatures between 370-700 ⁰ C in an oil-rich gas, and Coke are mined. The Ab-

109884/1174

The pyrolysis furnace 126 gas is generally rich in oil Gas fed to a condenser 128 in which oils and water formed during pyrolysis are precipitated will. The condensate is fed to a plasma separator 130 which separates the oil from the water. The oil, together with the oil obtained in the phase separator 122, becomes a high quality in the hydrogenation column 124 Hydrogenated synthetic oil. The resulting oil has a relatively low molecular weight and a high one Content of aromatic substances.

The coke of the pyrolysis furnace 126 is fed to the pyrolysis furnace, in which it is converted at temperatures between approximately 680 to 1300 ⁰ C in one or two stages into a hydrogen-rich gas and a coke with a high heat content and a low sulfur content suitable as fuel for power stations. After the gas has passed through condensers 120 and 128, it is fed to a gas purifier 132 in which the condensable chemicals are condensed while the remaining high methane gas is subjected to purification operations (not shown) to recover HCl, Hi ¹ and HpS (which will eventually be converted to sulfur). As already mentioned, the hydrogen-containing gases are used for hydrogenation operations.

The condensed chemicals and water from the gas cleaner 132 are fed to a phase separator 134, in which oxidized and aromatic chemicals arise as a liquid fraction. The rest of the condensed organic Substances are fed to the hydrogenation column 124 for conversion into oil. All occurring after stripper 136 Residual gases are mixed with the gas flow from the gas cleaner 132. That from the bubble separators 122, 130 and 134 draining water is shared with a water treatment 138 for the recovery of all water-soluble Chemicals supplied.

109884/1174

The one created by pyrolysis and degassing Coke can contain valuable minerals, e.g. gold, Silver, phosphates, aluminum or the like. In these cases gold and silver are cyanite treated with the coke recovered while phosphates, soluble salts, aluminum and other metals by acid treatment or an etching treatment or the like. of the coke can be recovered.

The most varied of organic residues can be used for the enrichment of the organic residues fed into the pyrolysis furnace Use types of fuel; a particularly suitable fuel however, it is coal. This leaves the pyrolysis products of the coal together with the pyrolysis products of the Obtain organic residues in one surgical step. The presence of coal also causes the The pyrolysis process is stabilized, a more even and steady operation is guaranteed and a relatively high one The calorific value of the resulting coke is ensured. As mentioned earlier, coal provides a broader base for improvement the economy of the recovery process and allows the placement of one of the coke products consuming power plant next to the processing plant for solid waste.

The coal can either be fed directly into the furnace or at an earlier stage in the process can be used, e.g. as a filter bed for waste water or as a filter with an acidic coating. When the coal is used up, it can be put in the pyrolysis oven to treat the organic residues. However, it is Note that for many modes of operation, coal or other carbonaceous materials are not required are.

The inventive method is for processing the

109884/1174

suitable for a wide variety of solid waste; household waste, industrial waste, animal waste, Processing waste from the food industry, vehicle tires and hospital waste. If the solid garbage Contains a high proportion of plastics, these can be removed by flooding, electrostatic or particle size separation or the like. separate from the organic fraction. Alternatively, the plastics can be appropriately crushed and fed to the pyrolysis zone for conversion to coke and chemical by-products.

The invention essentially consists in the following: solid waste is crushed and converted into an organic fraction and a metal-inorganic fraction is separated. The organic fraction is used for pulp recovery processed and the rest pyrolyzed. The organometallic fraction is used to recover the main metal and inorganic components processed.

109884/1

Claims (18)

Expectations 1. Process for the recovery of valuable components from solid waste characterized in that the solid waste is crushed (10, 24, 60, 80); that the crushed solid waste through a flood separation (12, 28, 64) are broken down into an organic fraction and an inorganic-metallic fraction; that the organic fraction in a pulp is reformed (14, 20) from which the paper pulp is separated so that an organic residue remains; and that the organic residue is converted by pyrolysis (36) into coke and a gas stream containing condensable hydrocarbons and gases. 2. The method according to claim 1, characterized in that magnetic-ferritic materials before the separation (64) into an organic fraction and an inorganic metallic fraction magnetically from the crushed solid waste is separated (62). 3. The method according to claim 1, characterized in that magnetic-ferritic materials after the separation into an organic fraction and an inorganic-metallic fraction (28) are magnetically separated from the inorganic-metallic fraction (40). 4. The method according to any one of claims 1 to 3, characterized in that tinned iron parts of the magnetically ferritic materials of organic residues freed, de-tinned and further crushed. 109884/1174 5. The method according to any one of claims 1 to 4, characterized in that that at least one! Dell of the waste paper before the separation ia an organic fraction and a Inorganic-metallic fraction (28, 64) separated from the shredded waste by a gas stream (12) and is formed into paper pulp (14). 6. The method according to claim 5, characterized in that the gas flow is a hot gas flow. 7. The method according to any one of claims 1 to 6, characterized in that that the organic residues are pyrolyzed in the presence of carbonaceous materials become (36). 8. The method according to claim 7, characterized in that the carbonaceous material is coal. 9 * Process according to one of Claims 1 to 7, characterized in that the pyrolysis is carried out at a temperature of approximately 400 to 1000 ^° C. 10.Verfahren according to claim 9, characterized in that the resulting coke is ^{degassed at a temperature of about 650 to 1100 0} C to generate a hydrogen-rich gas. 11.Verfahren according to any one of claims 1 to 10 characterized characterized in that the inorganic-metallic fraction by means of a heavy material separation (70) in a Heavy metal fraction and a fraction containing inorganics and aluminum is divided. 12.Verfahren according to claim 11, characterized in that those containing inorganic substances and aluminum 109884/1174 Fraction through a separation based on differences in particle size into an inorganic fraction and an aluminum fraction is broken down. 13. The method according to claim 11, characterized in that Copper and zinc are leached from the heavy metal fraction with the help of ammonia; that copper from the resulting solution is stripped; and that copper is recovered by electrolysis. 14. The method according to claim 13, characterized in that the zirconate-containing carbonate salts according to the Copper strips are precipitated from the solution by adding carbonate. 15. The method according to any one of claims 1 to 14, characterized in that that the inorganic-metallic fraction for gemstone separation a Fettisch (78) and for Separation of coins and valuable metals is fed to a set board (100). 16. The method according to claim 12, characterized in that glass by a flood separation from the inorganic Fraction is separated. 17. The method according to claim 16, characterized in that glass containing magnetic-ferritic components through a high-intensity magnetic separation of from Ferritic components free glass is separated. 18. The method according to any one of claims 1 to 17, characterized in that plastics by density unterohiede or separated from the organic fraction by suspension. 1 0 9 0 0 U! 1 .1 7 U