JP2000202402A - Stabilizing method of water insoluble heavy metal - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To improve the immobilization of heavy metals in waste or pollutants while supplying remaining available processing chemicals to stabilized waste, and to treat waste. To provide a method for stabilizing water-insoluble heavy metals, which reduces the deterioration of chemical stabilization due to operation, and thus reduces waste re-use and disposal costs. SOLUTION: Maintaining free fluidity after immobilization treatment,
A method for immobilizing heavy metals in free-flowing dry or wet waste, comprising contacting the waste with an effective amount of a water-insoluble or water-inhibiting stabilizing agent, the Federal Register 55: 126. No. 26985-26998
A method consisting essentially of reducing the leaching of heavy metals to a level below the regulatory values measured in the EPA TCLP or STLC tests performed on the resulting treated wastes, as described on page.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for stabilizing a water-insoluble heavy metal. More particularly, stabilization of heavy metals from solid residues, especially lead in solid waste and ash residues from the incineration or combustion of fluffy waste produced by crushing wires and motor vehicles. The present invention relates to a method for stabilizing cadmium.

[0002]

BACKGROUND OF THE INVENTION The leaching of wastes containing heavy metals and the exposure of humans and organisms to heavy metal components has long been a subject.
It was important for environmental regulators and waste producers. Under the Resource Conservation and Restoration Act (RCRA), solid waste is subject to the Toxicity Characteristic Leaching Procedure (T) by the United States Environmental Protection Agency (EPA).
If excess heavy metals are leached from waste when tested under CLP), it is classified as hazardous waste. EPA
Also regulates the soil treatment of wastes containing certain heavy metals, depending on the heavy metal content, regardless of leaching potential. In addition, some state governments require that solid waste with higher levels of heavy metals be treated as hazardous waste. Treating waste at a landfill for hazardous waste is generally more expensive than treating it at a landfill for non-hazardous waste.

Under the Japanese leaching test, waste that leaches heavy metals above drinking water levels under a 6 hour leaching test is regulated as hazardous and has a specially delineated and costly waste treatment. It is allowed to be processed on the ground.

In order to reduce the costs associated with treating waste that can leach heavy metals, particularly lead-containing waste, at landfills, there is a method of controlling the leaching of various heavy metals to reduce heavy metals. Is being developed. These methods include acid digestion and subsequent recovery of the extracted metal,
Includes stabilizing lead-containing waste with, for example, Portland cement, silicates, sulfates, water-soluble phosphates, and combinations thereof. However, these methods are often expensive to perform and require complex handling equipment and operations. In addition, some of these methods use chemicals, such as high molarity acids, in usages that are highly corrosive to equipment in waste generation and / or treatment processes. These methods also change the nature of the waste, complicating the ability of the waste to be further processed. These methods include the treatment of chemicals that act as seeds in the waste to provide treatment capacity for the chemicals that are reduced for the removal of aqueous solutions and remain after use during further wet treatment of the waste. Water-soluble chemicals that release capacity are also used.

[0005] Therefore, there is a need for a means for reducing the leaching of lead from waste containing lead, which is not expensive and allows further processing and handling of the waste after stabilization without significant damage to the equipment. is there.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to improve the immobilization of heavy metals in waste or contaminants while providing the remaining available processing chemicals in stabilized waste. The present invention is intended to reduce the deterioration of chemical stabilization due to waste treatment and operation, thereby improving the reuse of waste and reducing treatment costs.

[0007]

The gist of the present invention is as follows.
A method for immobilizing heavy metals in free-flowing dry or wet waste, which maintains free flow after the immobilization treatment, comprising the steps of: stabilizing the waste with water insoluble or inhibiting water solubility. EP made on treated waste generated as described in Federal Register 55, Vol. 126, Nos. 26985-26998, in contact with an effective amount.
A A method consisting essentially of reducing the leaching of heavy metals to a level below the regulatory values measured in TCLP or STLC tests, (2) wherein the stabilizer is a natural mineral, phosphate rock,
The method according to (1), wherein the stabilizer is a water-insoluble chemical selected from the group consisting of pulverized phosphate rock, calcium carbonate, magnesium oxide, and carbon. (3) The water-soluble chemical having a water-insoluble coating. A water-insoluble drug containing a drug, wherein the water-soluble drug is selected from the group consisting of triple superphosphate, lime, superphosphate, dolomite lime, lime, Portland cement, silicate powder, carbonate, sulfate and sulfide. The method according to (1), wherein the surface coating selected and applied on the water-soluble precipitant provides water-insoluble or water-resistant surface properties, (4) the stabilizer is water-soluble, (5) The method according to (1), wherein the waste is produced from combustion of solid waste, wherein the bottom ash is formed in a shape (for example, pellets, lumps, small spheres, films) that prevents Flyer (1) The method according to (1), wherein the waste is selected from the group consisting of: a residue of a dust collector, a residue of a dust collector, and a combination thereof. And (7) the method of (1), which is selected from the group consisting of crushed dusts generated from a combination thereof, and (7) remains stable in the waste during the wetting or handling step of the waste. A method for immobilizing heavy metals in waste with an agent, comprising essentially contacting the waste with a water-insoluble or water-inhibiting stabilizing agent, said stabilizing agent comprising: It can always remain in the waste matrix under normal handling conditions when the waste is moistened, and when manufacturing or recovering the waste, the wetness of the waste when contacted with cooling, spraying or water Water insoluble during formation (8) Wetting the waste in a dry or wet state or attaching a stabilizing agent to the surface of the waste when handling it, and disposing of The method according to the above (7), wherein the stabilizer is pulverized in order to capture and remain in the material particles.
(9) The stabilizer is lime triphosphate, superphosphate,
(10) The method according to the above (7), which is crushed phosphate ore, pebble lime or magnesium ore, wherein the stabilizer comprises a water-soluble chemical having a water-insoluble coating, and the water-soluble chemical is triple super phosphorus. (11) The method according to (7), wherein the method is selected from the group consisting of acid lime, superphosphate, dolomite lime, lime, Portland cement, silicate powder, carbonate, sulfate and sulfide. Is contacted with at least one immobilizing agent in an amount of 0.01 to 20.0% by weight based on the total amount of the waste.
(12) The method according to (7), wherein the waste is contacted with at least one immobilizing agent in an amount of 0.01 to 20.0% by weight based on the total amount of the waste. )
A method of immobilizing heavy metals in free-flowing dry or wet waste or heavy metal contaminated material that maintains free flow after the immobilization process, comprising: removing the waste or contaminants from the federal register 55; Volume 126 number 269
California leaching test, leaching test by Japanese method or EPA, performed on generated treated waste or contaminants, described on pages 85-26998.
Consisting essentially of contacting with an effective amount of a stabilizer that reduces leaching of heavy metals to a standard below the regulation value measured in the TCLP test, said stabilizer comprising phosphate ore, ground phosphate ore, triple Selected from the group consisting of lime superphosphate, superphosphate, silicate, magnesium oxide, sulfate, sulfide and lime, wherein the immobilizing agent is cooled, sprayed or water-discharged during the production or recovery of waste. A method for immobilizing heavy metals by contacting with the waste or contaminant when moistening the waste or contaminant, thereby immobilizing heavy metals, (1)
4) The method according to (13) above, wherein the waste is selected from the group consisting of bottom ash, fly ash, residue of a dust collector, and a combination thereof, generated from combustion of solid waste. 15) The method according to (13), wherein the waste is selected from the group consisting of crushing of automobiles, crushing of wires, crushing of large household items, and crushed dust generated from a combination thereof. (17) The method according to (13), wherein the material is contacted with at least one immobilizing agent in an amount of 0.01 to 20.0% by weight based on the total amount of waste, (17) Wetting or handling of waste A method of immobilizing heavy metals in waste or contaminated with heavy metals using a fixing agent that remains in the waste or contaminants during the process. Consisting essentially of contacting with a stabilizer selected from the group consisting of magnesium oxide, sulphate, sulphide, lime, triple superphosphate, lime ore, superphosphate and crushed phosphate ore The said chemicals can always remain in the waste or contaminant matrix when the waste or contaminants are wetted when cooled, sprayed or brought into contact with water during the production or recovery of the wastes Wherein the waste is selected from the group consisting of bottom ash, fly ash, dust collector residue, and combinations thereof, resulting from the combustion of solid waste. (19) The method according to the above (17), wherein
(20) The method according to the above (17), wherein the waste is selected from the group consisting of crushed automobiles, crushed wires, crushed large household items, and crushed dust generated from a combination thereof. , 0.0 to the total amount of waste
(21) The method according to the above (17), wherein the amount of the immobilizing agent is brought into contact with at least one immobilizing agent in an amount of from 1 to 20.0% by weight. A method of immobilizing heavy metals in wet ash, wherein the wet ash is made of triple superphosphate, phosphate rock, silicate, magnesium oxide, sulfate, sulfide, lime,
Consisting essentially of contacting with a stabilizer selected from the group consisting of superphosphate and milled phosphate ore, such that the chemicals must be incorporated into the wet ash matrix during waste production or recovery. Can survive,
(22) a method for fixing a heavy metal thereby, wherein the stabilizer is brought into contact with wet ash before its recovery;
(1) The method described in (23) In the process of wetting or handling the waste, the heavy metal in the crushed residue resulting from the cutting of the wire or the crushing of the automobile is removed by a stabilizer remaining as it is in the crushed residue. A method of immobilizing, wherein the crushing residue is selected from the group consisting of lime, triphosphate, silicate, magnesium oxide, sulfate, sulfide, lime, phosphate rock, superphosphate and ground phosphate rock. Consisting essentially of contacting with a stabilized stabilizer, said stabilization comprising:
During the production or recovery of waste, when cooling, spraying or contacting with water, it can remain in the matrix of the crushed residue when the crushed residue is moistened, thereby immobilizing heavy metals How to make (24)
(25) The method according to the above (23), wherein the crush waste is crush residue of a car or insulator waste of wire cutting.
The method according to (1), wherein the heavy metal is selected from the group consisting of lead, cadmium, copper and zinc; and (26) the heavy metal is selected from the group consisting of lead, cadmium, copper and zinc. (17).

[0008]

DETAILED DESCRIPTION OF THE INVENTION In one aspect, the present invention provides:
A method is provided for immobilizing heavy metals, such as lead, in free-flowing dry or wet waste or contaminants that maintain free flow after the immobilization process. The waste or contaminant is contacted with an effective amount of a stabilizer which is water insoluble or inhibits water solubility, and fed to the Federal Register 55 126 No. 26985-2.
Heavy metals to standards below the lead limit (eg, 5 ppm) measured in the EPA TCLP test made on page 6998 or leaching test in California or EPA TCLP test made on treated waste generated as described in Japanese leaching test standards To reduce leaching. In another embodiment, heavy metals in the waste are immobilized, such as by wetting the stabilizer or leaving it in the waste during the handling process. The method can ensure that waste or contaminants remain in the waste matrix under standard handling conditions, and when manufacturing or recovering waste,
It consists essentially of leaving water insoluble upon wetting of the waste when contacted with cooling, spraying or water, or contacting with a stabilizer which inhibits water solubility, thereby immobilizing heavy metals. In one embodiment, the residue comprising heavy metals in the form of incinerator bottom ash, alone or in combination with other lead-containing waste, provides an effective amount of water and milling for cooling or dust control such as ash. Some heavy metals are immobilized such that the solids formed and remaining are below the TCLP limit by contact with a stabilized stabilizer such as phosphorous ore. In a more detailed aspect, the amount of ground phosphate rock is from about 0.5% to 20.0%, preferably from about 0.5% to 5.0%, of the wet weight of the ash.
%, More preferably about 0.5% to 2.0%.

The material to be treated according to the invention is a waste or contaminant containing heavy metals, preferably crushed residues obtained from large household appliances (for example appliances such as ovens, dishwashers, refrigerators after consumption). Fines of waste separated from ferrous and non-ferrous metals produced by the cutting of materials, wires and crushing operations of automobiles, as well as iron and other products normally produced with ash and / or bottom ash from the combustion of solid waste. It is a non-ferrous metal. Such wastes, materials and residues are in USEPATCLP
5.0 ppm (5 mg) as determined by leaching test
/ L) and high levels of lead and cadmium that can leach at levels above 1.0 ppm (1 mg / l) and 25.0 as measured by the California leaching test method.
ppm and more than 200.0 ppm of copper and zinc and, for example, 0.01 ppm of lead on a water-soluble desorption test standard specified by the Japanese EPA. When it ’s dry,
The initial physical characteristics of such solid residues and ash are:
It is a free-flowing particle mass, and the advantage of the present invention is that
Since the solid ash residue retains the initial free-flow granular properties important for handling after the process of immobilizing these metals, i.e., the weight, density and cohesive properties of the solid residue have not changed significantly, There is no need to partially change the handling equipment. The present invention does not alter the drainage of critical ash or change the size of the ash, as the solid ash product produced in its initial form is suitable for drainage, handling, landfill and reuse. .

[0010] The following description of the present invention is directed to incinerator ash only produced from the combustion of solid waste. This represents a convenient way to carry out the invention,
The selection of this characteristic description is for convenience of explanation only. Mixture of ash with other solid residues such as cotton litter and treatment of other solid residues, soil contaminated with heavy metals,
Treatment of other solid waste or solid materials, such as car crushed residues, wire cutting insulation waste, foundry sand, sand blast waste, ferrous and / or non-ferrous scrap residues after combustion, or Process ash independently,
It will be appreciated that modifications, such as combining it with other inert solid residues, are intended to be included in the present invention as other substitutions as would be recognized by one of skill in the art.

[0011] Incinerators for incinerating debris and other solid waste are well known to those skilled in the art. Bottom ash generated from the incinerator remains on the furnace grate after incineration of waste. Bottom ash is often granular, somewhat glassy in nature, and contains ferrous and non-ferrous metals, which are separated by mechanical and electromechanical means such as sieving, electromagnetic, eddy current separation, etc. Well collected from bottom ash. Other inert materials produced by burning solid waste are fly ash, which is a fine substance that floats in the air in the furnace, and can be used in various forms, such as fiber filters, electrostatic precipitators, cyclones, and combinations thereof. Captured by a form of air pollution control unit. The bottom ash produced during the combustion of the waste is sometimes mixed with the fly ash so that it can be mixed with the fly ash and combined for use in an ash treatment system. Bottom ash is 15 meters from the bottom of the incinerator grate.
00 to 2500 ^. Since it is discharged at high temperatures in the range F 2, it is necessary to cool it with air and / or water before further processing. The most common method of cooling the ash is to cool it with water in a drag tank or ram discharge tank, which also acts as a seal to restrict airflow into the bottom of the furnace. Bottom ash is discharged from the wet cooling tank by means of either a pushing ram or drag flight, which allows the ash to be moistened in a water bath and control the time to cool before discharging to the removal conveyor . Both methods of cooling and discharging common ash are held by bottom ash,
Includes a drainage device inclined after the bath that allows cooling water not adsorbed or captured to be returned to the cooling tank.
The water retained by the bottom ash and the water lost by evaporation due to the heat-exposed water seal is supplemented by fresh treated water called makeup water. Referring to FIG. 1, the main contact tank 10 for bottom ash
Bottom ash the stabilizer using the stabilizer 11 added to the tank 10 via the water supply 12 at a rate that maintains the desired concentration of the stabilizer suspended in the solution. Is one possible contact to apply to The bottom ash 13 will be removed by the discharger 14 at a rate that not only allows the ash to contact the stabilizer solution for the desired time, but also controls the ash mass released from the incinerator unit. The concentration of the stabilizer solution and the retention time are determined by TC
It will vary based on the desired reduction in heavy metal content in the ash, as well as on the requirement for a reduction in soluble metals when evaluated under LP and other state regulatory testing methods. The immobilization of heavy metals from the ash is completed in a tank reactor separate from the cooling tank, so that the ash cooling tank is performed in a batch mode rather than a continuous flow mode. If the bottom ash was placed in a batch reactor separated from the furnace ash wet cooling tank after contact with the stabilizer solution tank for some control time, preferably by gravity drainage on the inclined drag chain bed 15 or inclined ram Alternatively, the bottom ash is subjected to a dewatering step by overhead drainage. Stabilizer 11 is injected via air blowing means into duct 16 on the intake side of air pollution recovery device 17 of the installation, and then with or without stabilized bottom ash, mechanical means It can also be conveyed by 18 to a discharge point 19.

In practicing the present invention, water-insoluble stabilizers or water-insoluble coatings in the form of agglomerates or other forms which inhibit water solubility during the wetting of waste during stabilization. Any convenient water-insoluble stabilizer, such as a water-soluble stabilizer covered with, can be used. Stabilizers for contact with waste or contaminated materials containing heavy metals may be used during normal handling or when contacting water during cooling, spraying or waste production or recovery. Should remain in the waste matrix upon wetting of the waste. The water-insoluble stabilizer can be applied to the bottom ash in either a slurry or dry form. The immobilizing agent has a particle size,
Water-resistant, solid phosphates (e.g., by shape, properties or agglomeration, or by surface coatings engineered to be applied to the surface of other water-soluble chemicals, e.g.,
Phosphate rock, prilled (spheronized) superphosphate, lime triphosphate, carbonate (eg, calcium carbonate),
Carbon, sulfide, magnesium oxide and combinations thereof may be included. In one embodiment, as described below, triple superphosphate, lime, superphosphate, dolomite lime, lime, Portland cement, pebble lime, magnesium ore, silicate powder, carbonate, sulfate and The sulfides can be prilled and / or surface coated to minimize premature release of the stabilizing agent. Polymeric coatings on water-soluble triple superphosphate (TSP) are used to control phosphate and nitrogen release times in potted and non-potted soils for rose and flower plants. This is an example of a commonly used coating chemical. In any application, the choice of a water-insoluble coating on a stabilizer or water-soluble chemical will use or expose the ash and / or material to rainwater, rinse water, separation water, processing water and / or cooling water. Simulated leaching conditions, acid rain, and groundwater / surface water in landfills to minimize premature release of stabilizing chemicals, and at high liquid-solid ratios simulating those used on the ground Allowing organic acids such as dilute acetic acid, buffered acetic acid and / or citric acid to cause the release of stabilizing chemicals only during exposure of the mixed waste and / or material Is the key to Therefore, TCLP or California WET, designed to simulate the leaching of the target waste under leaching conditions or high-water leaching conditions of landfills that are decomposed under stirring, as measured by the Japanese test method. (Soluble Threshold Leaching Criteria); S
Exposure of the stabilized waste and / or material to the TLC) extract will result in the release of water-insoluble chemicals (precipitating agents). Preferred stabilizing chemicals for waste and / or material containing Pb are ground phosphate rocks such as natural phosphate of North Carolina (NATURALPHOSPHATE) and similar pre-sour phosphate minerals.

The amount of stabilizer added to the ash or other solid residue combined with the ash to ensure proper TCLP, STLC or water test immobilization depends on the alkalinity of the bottom ash, It will depend on variables such as content, surface properties, and the level of TCLP / STLC / water leaching reduction desired for heavy metals. 0.5 wet weight% of ash added to ash production line before recovery or dewatering
~ 1.0% by weight of water-insoluble phosphate rock is TCLP / ST
LC / water standards are 5.0 ppm for Pb, 1.0 ppm for Cd and 0.01 / 0.05 for water.
Seems to be sufficient to convert heavy metals sufficiently, such as to be lower than the regulatory value of. However, the foregoing may be based on the rationale or need for given regulatory standards or differences in the initial metal content and properties of the ash, as indicated by the use or application of higher or lower stabilizers. Not intended to eliminate.

The leaching characteristics of ash TCLP / STLC / water have been found to vary greatly with equipment location and ash production mode, which is due to regulators and ash leaching and total metal properties. Are anxious to those who might use it.

[0015]

The following examples are merely illustrative of the present invention and do not limit the invention in any way.

EXAMPLE 1 In this example, bottom ash from a solid waste combustion facility using a ash cooling tank was first referenced to stabilize and characterize the ash before treatment. TC
LP analysis was performed. Bottom ash reference sample is federally registered (Federal Register) Vol. 55 No. 126
Federal Register, Vol. 55, No. 61 (19) corresponding to the part related to the method described on pages 6985-26998 (June 29, 1990).
(March 29, 1990), both of which are incorporated herein by reference (Toxic
ity Characteristic Leaching Procedure) (TCLP)
Was served. This test method is also described in EPA SW846 Third Edition. Filtration solutions containing soluble metals were prepared in aliquots by the TCLP test and analyzed by ICP-MS. Next, 0.5%, 1.0% and 2.0% by weight of ground phosphate rock (Rock-P) and 0.5%, 1.0% and 2.0% by weight were added to the bottom ash. Weight percent polymer-coated triple superphosphate (Poly TSP) was added, followed by TCL
A P test was performed. Table 1 shows the reference sample of ash and the Pb concentration after stabilization as approximate average values. The results clearly confirm that water-insoluble phosphates and polymer-coated phosphates are suitable for TCLPPb stabilization of incinerator bottom ash.

[0017]

[Table 1]

Example 2 In this example, a wire from copper and aluminum wire for resale of copper and aluminum was used to stabilize and characterize the waste insulator prior to processing. Wire cut waste insulation produced from a facility that separates insulation was first subjected to baseline TCLP analysis. Next, 0.5 wt%, 1.0 wt% and 2.0 wt% of ground phosphate rock (Rock-P) and 0.5 wt%, 1.0 wt% and 2. Lime triple phosphate (Poly T) coated with 0% by weight of polymer
SP) was added and then subjected to the TCLP test. PVC
And by floating the PE, the waste insulator is often wet cooled to recover additional amounts of copper and aluminum from the heavier metal fraction, and the stabilized insulator is also water cooled, TCLP tests confirmed that the phosphate species remained with the insulator and reduced TCLP leaching with little dissolution or reaction in the water bath. Table 2 shows the standard substances of waste and the Pb concentration after stabilization as approximate average values. The results show that TC in either dry or wet use
It is clearly confirmed that water-insoluble phosphates and phosphates coated with polymers are suitable for the stabilization of the LP Pb insulator. The slight numerical change observed from the TCLP test of waste from dry to wet is:
Probably due to the non-uniformity of the Pb content in the insulator because it is based on grams to grams,
It does not appear to correlate with the loss of fine phosphate in the wet separation process or the surface reactivity of the water-insoluble phosphate.

[0019]

[Table 2]

Embodiment 3 In this embodiment, the waste insulator obtained by cutting the wire is
0.5%, 1.0% and 2.0% by weight of unmilled phosphate rock (Rock) were added, followed by TC
It was subjected to an LP test. Under the TCLP test, the effect of milling of phosphate rock on the availability of sites to stabilize surface active phosphate Pb, as well as the effect of milling on controlling the transfer of chemicals from the waste insulator. The unmilled phosphate rock was examined to determine the effect. 85% of the milled phosphate rock used in Examples 1 and 2 was 2
While passing through 00 mesh, the unmilled phosphate rock used passed 100% at 14 mesh, 97% at 35 mesh, and 49% at 65 mesh.
%, 100% at 19 mesh and 2
It had a Tyler mesh particle size distribution of 1% passing through 00 mesh. The use of uncrushed phosphate rock for the insulation of a dry wire can be achieved by using a wire insulation 10
By shaking a 1000 ml container using 0 g and 2% phosphate rock, 50-60
% Was found to move. This migration phenomenon is considered to be troublesome because the stabilizing chemical does not stay completely in the waste irrespective of the mixing method used. Stabilized waste truck loading when phosphate ore, crushed phosphate ore and / or TSP migrates from the top of the waste insulator to another location and is received at the landfill after transportation vibration In order to determine if the composition for TCLP sample analysis was lost from the upper layer, dry insulation and small amounts of phosphate rock, ground phosphate rock and low-density triple superphosphate (TSP) were used. Road transport of a mixture of spheres was simulated in a laboratory. The simulations used TSP with 2% by weight of well mixed phosphorus ore, ground phosphate ore, and dry insulator waste on a vibrator table set at 120 strokes per minute. To be included. Next, the apparent waste sample was recovered from the sample on the shaker table for TCLP analysis. Reference sample of waste and Pb after stabilization
The concentrations are shown in Table 3 as approximate averages. From the results,
Water-insoluble, unmilled phosphate is not as effective as milled phosphate or TSP during passing through the TCLP, and the unmilled phosphate ore may vibrate after use of the phosphate ore. T of the sample recovered from the one received
It is clearly ascertained that it allows movement which greatly increases the CLP criterion. The milled phosphate ore covered the insulator and remained a uniform coating on the waste regardless of vibration. The TSP globules also remained completely in the waste insulator and did not migrate, but the globules did not adhere to the insulator as did the ground phosphate. The globules are 55-60 pounds per cubic foot very similar to 45-50 pounds of waste insulation per cubic foot.
The density of the pounds, the hemispherical shape and the ability of the globules to remain between the bridges of the waste insulation without separation 6-6
Due to the Tyler mesh size of 16 mesh, it remained uniformly in the waste insulator. Small balls are also 25-30
Placed at an angle of degrees, it had a somewhat irregular surface that improved the bridging action of the globules in the matrix of the insulator waste.

[0021]

[Table 3]

Example 4 In this example, an ash dust master (DUST) was used to stabilize and characterize the ash before processing.
MASTER) Using a mixer and a controller for wetting of the ash, the residue of the fly ash precipitator from the combustion facility of the fuel solid waste that induces the waste is first set to the reference T
CLP analysis was performed. Prior to collecting fly ash on the baghouse filtration equipment, 2.0% by weight of the Rock-ash is added to the fly ash by injecting the crushed phosphate rock (Rock-P) into the gas recovery equipment. P was added. Prior to baghouse filtration to collect fly ash residues after incineration of municipal solid waste, the fly ash and Rock-P are effectively mixed with each other in a gas stream and then fly ash And Rock-P
Was collected in a fly ash collecting hopper and transferred to a dust master (DUSTMASTER) mixer for adding water as dust control. DUS the fly ash and Rock-P
After mixing in a TMASTER mixer, a TCLP test was performed. Table 4 shows the fly ash reference sample and the Pb concentration after stabilization as approximate average values. The results clearly confirm that water-insoluble phosphates are suitable for the stabilization of TCLP Pb and Cd in residues of the incinerator fly ash dust collector.

[0023]

[Table 4]

The foregoing results show that waste residues and leachable soluble metals in the material are reduced and remain effective without reaction under water cooling and waste transfer conditions. The feasibility of the method for providing a stabilizing drug is easily established. The extent to which the leaching of heavy metals is reduced may be specified by the technician and will probably depend on the reference characteristics of the waste as well as the enforcement criteria in connection with the choice of waste recycling or treatment. The process allows a wide selection of operations, the selection and amount of water-insoluble precipitates,
There is greater flexibility for those who can adjust process variables such as the degree of wetting and when using stabilizing chemicals. Pb, the element of most interest to regulators, is 0.5-
The addition of 2.5% by weight of water-insoluble chemicals results in a favorable T
Will be reduced and controlled to CLP / STLC / water standards.

Although the present invention has been shown and described with reference to preferred embodiments, various changes can be made in form and detail without departing from the spirit and scope of the invention as defined in the appended claims. It will be appreciated by those skilled in the art that

[0026]

The present invention provides a means to reduce the TCLP / STLC / water variables of the ash, thereby improving ash recyclability and treatment options.

[Brief description of the drawings]

FIG. 1 illustrates one embodiment of the present invention in a schematic process illustrating an incinerator that allows for the use of water-insoluble phosphate rock before bottoms and fly ash are recovered.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4D004 AA21 AA26 AA28 AA36 AA37 AA46 AB03 AC04 BB03 CA15 CA32 CA34 CA47 CC03 CC06 CC11 CC12 CC13

Claims (26)

[Claims] 1. A method for immobilizing heavy metals in free-flowing dry or wet waste, which maintains free flow after the immobilization treatment, wherein the waste is water-insoluble or water-soluble. Contact with an effective amount of a stabilizing agent, and contact Federal Register 55, 126, 26985-269.
A method consisting essentially of reducing the leaching of heavy metals to a level below the regulatory values measured in EPA TCLP or STLC tests performed on the treated wastes described on page 98. 2. The method according to claim 1, wherein the stabilizer is a water-insoluble chemical selected from the group consisting of natural minerals, phosphate rock, ground phosphate rock, calcium carbonate, magnesium oxide and carbon. 3. The method according to claim 1, wherein the stabilizing agent is a water-insoluble chemical including a water-soluble chemical having a water-insoluble coating, wherein the water-soluble chemical is tricalcium perphosphate, superphosphate, dolomite lime,
A surface coating selected from the group consisting of lime, Portland cement, silicate powder, carbonates, sulfates and sulfides and applied on a water-soluble precipitant provides water-insoluble or water-resistant surface characteristics. The described method. 4. The method according to claim 1, wherein the stabilizer is water-soluble, but is present in a form that inhibits water-solubility (eg, pellets, lumps, small spheres, films). 5. The method of claim 1 wherein the waste is selected from the group consisting of bottom ash, fly ash, dust collector residue, and combinations thereof, generated from the combustion of solid waste. . 6. The method of claim 1, wherein the waste is selected from the group consisting of crushing automobiles, crushing wires, crushing large household items, and crushed dust generated from a combination thereof. 7. A method for immobilizing heavy metals in waste with a stabilizing agent which remains in the waste during the wetting or handling step of the waste, wherein the waste is water-insoluble. Or essentially consisting of contacting with a stabilizer which inhibits water solubility, said stabilizer being able to always remain in the waste matrix under normal handling conditions during the wetting of the waste, A method of immobilizing heavy metals by leaving water insoluble when moistening the waste when the waste is cooled, sprayed or brought into contact with water during the production or recovery of the waste. 8. Stabilizing the wetted waste in a dry or wet state, or stabilizing, in order to attach the stabilizing agent to the surface of the waste and to trap and remain in the waste particles. The method of claim 7, wherein the agent is ground. 9. The method according to claim 7, wherein the stabilizing agent is lime triphosphate, superphosphate, ground phosphate rock, pebble lime or magnesium ore. 10. The stabilizer comprises a water-soluble chemical having a water-insoluble coating, wherein the water-soluble chemical is lime triphosphate, superphosphate, dolomite lime, lime, Portland cement, silicate powder, The method of claim 7, wherein the method is selected from the group consisting of carbonates, sulfates, and sulfides. 11. The waste is added to the waste in an amount of 0.
2. The method according to claim 1, wherein the at least one immobilizing agent is contacted in an amount of from 1 to 20.0% by weight. 12. The waste is added to the waste in an amount of 0.
The method according to claim 7, wherein the at least one immobilizing agent is contacted in an amount of from 01 to 20.0% by weight. 13. A method for immobilizing heavy metals in free-flowing dry or wet waste or heavy metal-contaminated material, wherein the metals retain free flow after the immobilization treatment.
Dispose of waste or contaminants in Federal Register 55
Vol. 126, No. 26985-26998, based on the leaching test of California conducted on the treated waste or contaminants generated, the leaching test by the Japanese method or the standard value below the regulation value measured by the EPATCLP test. Consisting essentially of contacting with an effective amount of a stabilizer that reduces leaching of heavy metals, said stabilizer comprising:
Phosphate ore, crushed phosphate ore, triple superphosphate, lime, superphosphate, silicate, magnesium oxide, sulfate, sulfide and lime, wherein the immobilizing agent is used for producing waste or During collection, when cooled, sprayed or brought into contact with water, should be able to remain in the waste or contaminant matrix during wetting of the waste or contaminants, thereby immobilizing heavy metals Method. 14. The method of claim 13, wherein the waste is selected from the group consisting of bottom ash, fly ash, dust collector residue, and combinations thereof, generated from the combustion of solid waste. . 15. The method of claim 13, wherein the waste is selected from the group consisting of crushing automobiles, crushing wires, crushing large household items, and crushed dust generated from combinations thereof. 16. The waste is added to the waste in an amount of 0.
14. The method according to claim 13, wherein the at least one immobilizing agent is contacted in an amount of from 1 to 20.0% by weight. 17. A method for immobilizing heavy metals in waste or substances contaminated with heavy metals with a fixing agent that remains in the waste or contaminants during a process of wetting or handling the wastes. , Waste or pollutants,
Essentially from contacting with a stabilizer selected from the group consisting of silicates, magnesium oxides, sulfates, sulfides, lime, lime triphosphate, phosphate rock, superphosphate and ground phosphate rock. Thus, the chemicals can always remain in the waste or contaminant matrix when the waste or contaminants are wetted when cooling, spraying or contacting with water during the manufacture or recovery of the waste. A method of immobilizing heavy metals. 18. The method of claim 17, wherein the waste is selected from the group consisting of bottom ash, fly ash, dust collector residue, and combinations thereof, produced from the combustion of solid waste. . 19. The method of claim 17, wherein the waste is selected from the group consisting of crushed automobiles, crushed wires, crushed large household items, and crushed dust resulting from a combination thereof. 20. The method according to claim 19, wherein the waste is contained in an amount of 0.
18. The method according to claim 17, wherein the at least one immobilizing agent is contacted in an amount of from 01 to 20.0% by weight. 21. A method for immobilizing heavy metals in wet ash with a fixing agent that remains in the wet ash during the step of handling the ash, the wet ash being treated with triple superphosphate lime. , Phosphate rock, silicate, magnesium oxide,
Consisting essentially of contacting with a stabilizer selected from the group consisting of sulfates, sulfides, limes, superphosphates and milled phosphate rocks, wherein the chemical is used in the production or recovery of waste. A method in which heavy metals can be immobilized by being able to remain in a wet ash matrix. 22. The method of claim 21, wherein the stabilizer is contacted with the wet ash prior to its recovery. 23. A method for immobilizing heavy metals in a crushed residue resulting from wire cutting or automobile crushing with a stabilizer remaining in the crushed residue during a wetting or handling step of the waste. Stabilizing the crushed residue from a group consisting of tricalcium phosphate, silicate, magnesium oxide, sulfate, sulfide, lime, phosphate rock, superphosphate and ground phosphate rock. Consisting essentially of contact with an agent, the stabilization being carried out during the production or recovery of the waste, when cooling, spraying or contacting with water, the matrix of the crushed residue upon wetting of the crushed residue. A method that can always remain and thereby fix heavy metals. 24. The method of claim 23, wherein the crushing waste is automobile crushing residue or wire-cut insulation waste. 25. The method of claim 1, wherein the heavy metal is selected from the group consisting of lead, cadmium, copper, and zinc. 26. The method according to claim 17, wherein the heavy metal is selected from the group consisting of lead, cadmium, copper and zinc.