DE2426641B2 - WASTE DETOXIFICATION METHOD - Google Patents

Description

The invention is based on the object of detoxifying the Aofall occurring in any production.

The solution to this problem is based on the discovery that a poison contained in a waste is in a rock-like mass can be embedded in such a way that it does not come out of the mass even after prolonged washing leach more. The solution to this problem results from the claims.

The slurry resulting from the process of the invention cures at ordinary temperatures and printing into a rock-like mass. The time required for the slurry to harden is one Function of the temperature of the slurry, the amounts of aluminum contained in the slurry - or aluminosilicate and portland cement -. The time required for curing can therefore by increasing the amount of Portland cement or by decreasing the amount of water or by Lowering the amount of hazardous waste can be shortened. By doing any of these If parameters change, slurries can be prepared lasting an hour to several weeks Require formation of a hard rock. The formation of the sludge immediately improves the dangerous ones Leaching characteristic of degradation. Samples of the sludge taken just minutes after its formation removed and subjected to leaching

ίο were found that the leaching was at 5% of the value falls, which was derived from the water washes of the hazardous waste. In the description are all Quantities based on parts by weight.

The formation of the rock from the mud occurs due to crystallization, and the finished crystal structure contains all components from the implementation. Atoms, molecules or ions of the reaction participants form bonds with each other and the water molecules present. The rock is a hydrated one Crystal whose compressive strength increases over time and probably its highest strength after about six months, although after about 28 days there is only a slight increase in strength takes place. The atoms, molecules, or ions of the waste matter are crystalline within the Basic mass connected by chemical bonding or by inclusion, what is hereinafter referred to as crystalline Capture is called.

The crystalline rock-like mass in which hazardous waste is encapsulated obtained according to the invention has a permeability of less than 1 x 10- "cm see- 'and a compressive strength of 7.03 to 70.3 kg / cm ^{2 at} 28 days Preparation: In general, the permeability is 1 x 10 ^{5 cmsec -1} to 1 x 10- ⁸ cmsec ~ '.

The permeability is measured according to the method of E. Meldgwick, which in Phil. Mag. S. 7, Vol. 13, No 85, 1932, page 632. The compressive strength is according to the British Standard 1610 measured in a Model A 14 Clockhouse triaxial testing machine, which is manufactured by Clockhouse Ltd., New Barnet, Hertfordshire, England.

The hazardous waste can contain: aluminum, boron, cadmium, chromium, copper, iron, lead, manganese, Nickel, tin, zinc, arsenic, antimony, barium, cobalt, gallium, hafnium, mercury, molybdenum, niobium, strontium, Tantalum, thorium, titanium, vanadium, zirconium, selenium or silver or a compound of any of these elements. It can contain anions, such as fluoride, sulphate, phosphate, nitrate, nitrite, sulphite, cyanide, Sulphide, thiocyanate, thiosulphate, ferricyanide or ferrocyanide, and it can also contain an acid, Alkali, protein, carbohydrate, fat, drugs, Prussian blue or Turnbull blue, cleaning agent, mineral oil, Tar or lubricant.

According to the present invention, for example, the following wastes can be treated: Waste from the Mining and metallurgical operations, for example ore waste from mines and slag, especially those containing As, Cd, Cr, Cu, CN, Pb, Hg, Se, Zn or Sb;

Paint waste;

Solvent-free paint waste such as is used in heavy industry, especially in the automotive industry, attack;

Sulphide dye liquids;

inorganic catalysts that occur in a wide range of industries, for example in

petrochemical, the chemical industry in general or in the dye industry;
Waste from the electrical and electronic industry, such as waste from printed formwork, with the exception of chlorinated hydrocarbons;
Waste from printing and copying operations;

Waste from electroplating and metalworking;

Wastes from the explosives industry with the exception of the organic produced by that industry Waste;

Latex waste and cyanide, mercury and zinc waste, generated in the rubber and plastics industry;

Waste from the manufacture of electric batteries;
Textile waste;

Cyanide, arsenic, chromium or other inorganic waste from the petrochemical industry;
leaded fuel slurries;
Waste from the paper industry (paper lead);
Waste from the leather industry;

Inorganic waste from the general chemical industry;
Asbestos waste;

Washing fluids from incinerators and gas cleaning systems;
Silt and sewage from dredging companies;
Waste oxides from gas cleaning;
Waste from the cement and lime industries, such as dust captured in electrostatic precipitators;

Waste cyanide hardening;

Fly ash, for example the (! »! Firing of power plants, incinerators for household waste and sewage sludge etc .;
Sewage sludge;

Waste from the smelting and metalworking industries, for example waste from metal smelting and refineries, for example the aluminum, zinc, copper and / or lead refineries;

Waste from the iron and steel industry;
Sulphide bottles, for example calcium or sodium sulphide;
acid and alkaline wastes.

The aluminosilicate can be, for example, vermiculite; however, it is expediently fly ash, under which is the finely divided ash residue that arises from the combustion of pulverized coal, which is carried away with the exhaust gases from the ovens, in which coal is burned, and that from the gases usually by suitable precipitators, such as electrostatic, is absorbed.

Suitable Portland cements are those which comply with British Standards 12 (1958), 4027 (1966), 4248 (1968), 146 (1968), 4246 (1968), 1370 (1958) or 915 (1947).

The ratio of Portland cement to aluminum or Alumino-silicate is not stoichiometric and it is can range from: 1 to 1:50 for a given water content. Changes within this Area only affect the rate of settling and the ultimate compressive strength of the rock. Large amounts of portland cement, for example over%. promote fast curing and low Quantities of Portland cement, for example less than 5%, promote a high final strength.

The amount of water required for the reaction can be 10 times the total available Solids amount. Concentrations less than 20% are not sufficient to complete the product to hydrate and form a slurry. Larger amounts than 20% water increase the Settling time of the slurry. So needs a

ίο mud that contains 75% water, a longer one Time to obtain a certain compressive strength than a sludge containing 50% water. In the Setting these limits is no attempt to prevent the natural evaporation of the water in the To prevent or promote the atmosphere.

The amount of hazardous waste generated with a certain ratio of portland cement to aluminosilicate or aluminum silicate can be implemented depends largely on the nature of the hazardous Foldable and can be up to ten times the weight of aluminosilicate or aluminosilicate and portland cement. For any given mixture, the Increasing the amount of any particular hazardous waste to decrease the initial and the ultimate compressive strength of the rock obtained.

If the hazardous waste is neutral or alkaline, it becomes aluminum silicate or aluminosilicate and the portland cement is mixed and then the hazardous waste is added. If the hazardous waste is acidic, it is desirable to mix it with the Portland cement first and add the resulting mixture to the aluminum silicate or aluminosilicate. Water must be used during the Conversion between the waste material, the Portland cement and the aluminum silicate or aluminosilicate are present. The waste material can also be in the form of a liquid drain, as a semi-solid or solid are present, and if necessary, water must be added to the reaction mixture.

The increase in temperature accelerates the setting time considerably, which in turn leads to a Lowering the final strength of the rock leads. Optionally, in addition to the portland cement an oxide or hydroxide of aluminum or iron is present.

If a mixture of fly ash and an alkali metal silicate is used, the sludge sets very quickly with a certain water content and the resulting rock is harder, and surprisingly, arsenic or calcium present in the hazardous waste is more firmly encapsulated than if the alkali metal silicate is not present. The aluminum silicate or aluminosilicate is preferably used as a dry powder with a specific surface area in the range from 1500 to over 5000, preferably to 6000 cm ² per gram.

For example, the rock formed by the method of the present invention can be used for land filling, as a gravel layer, for the production of components, for the production of low-viscosity cement, for encapsulating other waste materials, such as household waste, or for reclaiming land from dismantled mines, Pits, excavations, lakes and estuaries by the sea. Household waste that is not even eligible for the procedure of the invention can be buried in a mass of slurry or rock, whereby the odors otherwise associated with household waste are suppressed and rodents are also kept away

can be. ". ,,"

The invention is more detailed in the following examples

described. .

In the examples, the reaction part name A is a dry, powdered, conventional Portland cement (analysis: CaO 63.1%; SiO ₂ 20.6%, Ai ₂ O ₃ 6.3%; Fe ₂ Oj 3.6%; sulphate as SO ₄ 2.0 %) and the reaction part name B is a finely divided, dry, powdery aluminosilicate (100% less than 200 meshes) (analysis SiO ₂ 49.0%; Al ₂ O ₃ 24.8%; Fe ₂ O ₃ 10.2% and traces of carbon and sulfur).

The "leached" is the solution obtained by grinding 10 g of the sludge hard, rock-like material to a fine powder and stirring with 100 ml of distilled water at 20 ^ magnetically stirred in one-meter for one hour Container and filter through a Whattman No. 1 Filter paper, unless otherwise stated, is given.

example 1

The test results are in the following table reproduced:

Metal M ppm in the filtrate

% Metal, leached from the rock

10

15th

20th

0.15
1.0

0.1
0.080.057

0.26

less than 1.0

0.009 0.033

0.042

0.018 less than 0.07

Example 3

30th

A slurry was prepared by mixing the following ingredients: 200 g of a finely divided (100% passed through 200 meshes) aluminosilicate Analysis: SiO ₂ 48.5%; Al ₂ O ₃ 27.5%; Fe ₂ O ₃ 8.0%). 40 g of a Portland cement (analysis: CaO 64.0%; SiO ₂ 20.5%; Al ₂ O ₃ 5.5%) and 108 ml of water, in which 2 g each of Pb (CH ₃ COO) ₂ , Zn (CH ₃ COO) ₂ , 2 H ₂ O, Cd (CH ₃ COO) ₂ , 2 H ₂ O, MnSO ₄ and SnCl ₂ · 2 H ₂ O was dissolved. The slurry produced hardened into rock within twenty-four hours. The materials were leached with water by stirring 10 g of the pulverized rock in 100 ml of water at 20 ^° C. for one hour in a magnetically operated tubular kettle. The solids were removed by filtration through Whatman No. 1 filter paper and the filtrate (leachate) analyzed for the respective metal. Less than 0.1 ppm of Cd, Zn, Mn and Pb were found in the filtrates, corresponding to an amount of less than 0.05% of each metal leached.

40

Example 2

A slurry was prepared by mixing the following materials: 200 g of dry, powdery aluminosilicate (100% less than 200 mesh) (analysis: SiO ₂ 49.0%; Al ₂ O ₃ 24.8%; Fe ₂ O ₃ 10 , 2% and traces of carbon and sulfur), 10 g Portland cement (analysis: CaO 63.1%; SiO ₂ 20.6%; Al ₂ O ₃ 6.3%; Fe ₂ O ₃ 3.6%; sulphate as SO ₄ 2.0%) and 108 ml of distilled water in which Xg of the metal salt MY _n , η H ₂ O [X = 20.0 g, M = Zn and Cd, Y = CH ₃ COO, m = 2, n = 2; A "= 20.0 g, M = Pb, Y = CH ₃ COO and m = 2, / 7 = 0; X = 20.0 g, M = Mn, Y = SO ₄ , m = 1, n = 4; X = 2.0g, M = Sn, Y = Cl, / 7J = 2 and / 7 = 2; X = IlJg, M = CU, Y = SO ₄ , / 77 = 2; /? = 5; X = 13 , 4 g, M = Ni, Y = SO ₄ , m = 1, π-β) was dissolved.

The resulting slurry adheres to a hard material in seven days. The material was leached with water by stirring 10 g of the pulverized rock in 100 ml of water at 20 ^° C. for one hour in a magnetically operated stirred kettle. The solids were removed by filtration through Whatman # 1 filter paper and the filtrate (leach) analyzed for metal M.

45

50

55

A sludge was prepared by mixing the following components: 100 g of reactant B, 100 g of reactant A, 50 ml of water and 400 g of an arsenic-containing waste that was obtained in a tin melt (analysis: water 75%; arsenic in the arsenate = 1 , 25% as AS; remote iron _{salts = l, 2o / O} as Fe manganese salts = 500 ppm as Mn; copper salts = 500 ppm as Cu; zinc salts = 2250 ppm as Zn; nickel salts = 15 ppm as Ni; lead salts = 650 ppm as Pb; Chromium salts = 5 ppm as Cr; cadmium salts = 65 ppm as Cd; tin salts = 400 ppm as Sn).

After three days the mud had hardened to form a rock, after seven days the rock had a compressive strength of 27.4 kg / cm ² and after twenty-eight days a compressive strength of 52.7 kg / cm *. The permeability (permeability) of the rock was after eleven days 1 x 10- ⁷ cm per second. The materials were leached after three days and the leach contained less than 0.1 ppm each of Sn, Cd, Pb, Mn and Cr and less than 0.05 ppm each of Zn and Cu. 0.16 ppm As and 0.5 ppm iron were found in the leach.

Example 4

100 g of water (analysis: water = 70%; sodium fluoride = 10% as NaF; calcium chloride -20% as CaCl ₂ ) and 70 g of reactant B and 15 g of reactant A were mixed to form a thick slurry. The mud hardens to a hard rock in two days. The materials were leached and found that the leach contained 2.0 ppm fluoride.

Example 5

100 g of one resulting from the burning of fuel oil Ash (analysis: carbon 65%; vanadium 2.7% as V; iron 2.0% as Fe; nickel 2000 ppm as Ni) mixed with 400 g of water, 50 g of reactant B and 100 g of reactant A to form a thick slurry which hardened in four days.

The materials were leached and found to be 0.18 ppm vanadium, less than Contained 0.1 ppm nickel and less than 0.05 ppm iron.

Example 6

100 g of a synthetic waste containing 10 g of antimony oxide Sb ₂ O ₃ and 90 g of water were mixed with 120 g of Reactant B and 30 g of Reactant A to form a thick slurry which hardened into hard rock in one day.

The materials were leached and found that the leach contained less than 2 ppm antimony.

Example 7

100 g of powdered sodium silicate (analysis: SiO ₂ = 76.7%; Na ₂ O = 22.9%), 100 g of aluminosilicate (analysis: SiO ₂ = 48.0%; A1 ₂ O ₃ = 27.2 %; Fe ₂ O ₃ = 9.1%; CaO = 3.4%; MgO = 1.9%; K ₂ O = 3.6%; Na ₂ O = 3.8%) and 100 g portland cement with 150 g of electroplating waste (analysis: pH = 6.3; zinc = 2.2% as Zn, copper = 500 ppm as Cu; lead = 800 ppm as Pb; suspended solids = none) and 100 g of a dry, bright, pulverized waste from a cement factory (analysis: CaO = 48%; Mg = 1.5%; K ₂ O = 12%; Na ₂ O = 2%) mixed into a thick sludge. The mud hardened to a hard solid in twenty-four hours.

The materials were leached and the leach was found to be less than 1 ppm Calcium and less than 0.05 ppm Zn, Cu and Pb, respectively.

Example 8

There were 100 g of an oily waste (analysis: 94.1% water; 2% mineral oil; 3% alkali and Alkaline earth salts) and 100 g of reactant B and 27 g of reactant A mixed to form a thick slurry which hardened to a hard solid within three days.

10 g of the rock-like solid were ground to a fine powder and ^{mixed with 100 g of water in a magnetically driven stirrer at 20 °} C. for one hour. The contents of the container were then centrifuged at 4000 rpm for five minutes and the liquid decanted from the solids. The liquid was found to contain no mineral oil.

Example 9

A strong smelling sulphide waste (analysis: sulphide = 4.1% as S ² -; sodium 5.9% as Na; water = 90%), 138 g of reactant B and 28 g of reactant A were mixed to form a sludge . The mud hardened into a hard rock-like material in three days with no noticeable odor. The materials were leached and the leach was found to contain less than 0.1 ppm of the sulphide as S ² -.

Example 10

100 g of electroplating waste (analysis: pH = 11.4, total cyanide = 3.9% as CN; Copper = 2.7%; suspended solids - none; Water = 91.2%) with 15 g sodium hydrochloride solution (15%) (usable Chlorine), 223 g dry gypsum waste, 134 g of reactant B and 34 g of reactant A to form a mixed in thick mud. The mud hardened into a rock-like solid in three days. the Materials were leached and the leach was found to be less than 0.01 ppm total of cyanide and 0.05 ppm copper.

Example 11

100 g of latex waste from an industrial upholstery shop (analysis: pH = 8.6; organic Content = 12.0%; inorganic content = 1.0%; Water = 87.0%) were with 20 g water and 25% Mixed sulfuric acid. 6 grams of hydrated glue was then added, followed by 40 grams of Reactant B and 40 grams of Reactant A and the whole mixed into a thick slurry. The mud hardened in three Days to a rock-like solid. The materials have been leached out. The chemical oxygen demand the leaching was 20 mg per liter, which is due to the ίο very low organic content of the leaching indicates.

Example 12

100 g of a cobalt-molybdenum catalyst used up in the oil refinery (Alumina powder containing 5% cobalt and 12% molybdenum, the elements present as oxides) were with 170 g of water, 170 g of des Reactant B and 40 g of Reactant A mixed into a thick slurry that increases within a day a solid rock-like solid hardened. The materials have been leached out. The leachate contained found to be less than 0.02 ppm cobalt as Co and less than 0.3 ppm as molybdenum.

Example 13

A slurry was made by mixing 6.4 tons of one at a metal finishing plant resulting sludge with 1.9 tons of common Portland cement and 5.95 tons of fly ash. One Analysis of the sludge showed:

dry solids at 105 ^° C. = 10.0% w / w, pH = 103;

Total cyanide = 20 ppm as CN; Total chromium = 270 ppm as Cr; Copper = 160 ppm as Cu;

Total iron salts = 7200 ppm as Fe; Lead = 340ppm Pb;
Nickel = 3000 ppm as Ni;
Zinc = 108 ppm as Zn.

Example 14

The mud hardened into one in four days

rock-like solid material. The materials were leached after fourteen days, and so was the leach contained less than 0.01 ppm cyanide and less than 0.1 ppm iron, nickel, copper, lead, zinc and chromium.

100 g of a digested sludge from the Bolton sewage works (analysis: dry solids at 105 ° C = 5.0%; Water = 95.0%) and 30 g of reactant A and 30 g of reactant B were zi mixed in a mud that hardened to a hard rock-like material within four days. There Material had no detectable odor in contrast to the very strong odor of the untreated Sewage sludge, and after a] ah it remained hard, inert, and odorless.

Claims (9)

Patent claims: 1. Method of detoxifying waste, thereby characterized in that the waste in the presence of water with a powder Aluminum and / or aluminosilicate and mixed with a Portland cement and the resulting Allow slurry to harden into a rock-like material. 2. The method according to claim 1, characterized in that there is fly ash as the aluminosilicate used. 3. The method according to claims 1 and 2, characterized in that one at a given water content Portland cement and aluminum or aluminosilicate in a ratio used from 50: 1 up to 1:50. 4. Process according to claims 1 to 3, characterized in that there is water in an amount at least 20% of the total solids present is used. 5. Process according to claims 1 to 4, characterized in that one has a neutral or alkaline waste from a mixture of Portland cement and aluminum or aluminosilicate admits. 6. Process according to claims 1 to 4, characterized in that one has an acidic waste Portland cement mixes and the resulting mixture the aluminum or aluminosilicate clogs. 7. Method according to the claims! to 6, characterized in that at the same time with the Portland cement an oxide or hydroxide of aluminum or iron is used. 8. Process according to Claims 1 to 7, characterized in that fly ash is used as the aluminosilicate used together with an alkali metal silicate. 9. Process according to claims 1 to 8, characterized in that a dry, powdery aluminum or aluminosilicate with a specific surface area of 1500 to 6000 cm ² / g is used.