CA2874325A1 - Fly ash and fly ash leachate treatment - Google Patents
Fly ash and fly ash leachate treatment Download PDFInfo
- Publication number
- CA2874325A1 CA2874325A1 CA2874325A CA2874325A CA2874325A1 CA 2874325 A1 CA2874325 A1 CA 2874325A1 CA 2874325 A CA2874325 A CA 2874325A CA 2874325 A CA2874325 A CA 2874325A CA 2874325 A1 CA2874325 A1 CA 2874325A1
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- CA
- Canada
- Prior art keywords
- fly ash
- leachate
- ash
- selenium
- treated
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B7/00—Working up raw materials other than ores, e.g. scrap, to produce non-ferrous metals and compounds thereof; Methods of a general interest or applied to the winning of more than two metals
- C22B7/02—Working-up flue dust
-
- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62D—CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS
- A62D3/00—Processes for making harmful chemical substances harmless or less harmful, by effecting a chemical change in the substances
- A62D3/30—Processes for making harmful chemical substances harmless or less harmful, by effecting a chemical change in the substances by reacting with chemical agents
- A62D3/33—Processes for making harmful chemical substances harmless or less harmful, by effecting a chemical change in the substances by reacting with chemical agents by chemical fixing the harmful substance, e.g. by chelation or complexation
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B30/00—Obtaining antimony, arsenic or bismuth
- C22B30/04—Obtaining arsenic
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B34/00—Obtaining refractory metals
- C22B34/20—Obtaining niobium, tantalum or vanadium
- C22B34/22—Obtaining vanadium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B34/00—Obtaining refractory metals
- C22B34/30—Obtaining chromium, molybdenum or tungsten
- C22B34/32—Obtaining chromium
-
- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62D—CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS
- A62D2101/00—Harmful chemical substances made harmless, or less harmful, by effecting chemical change
- A62D2101/08—Toxic combustion residues, e.g. toxic substances contained in fly ash from waste incineration
-
- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62D—CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS
- A62D2101/00—Harmful chemical substances made harmless, or less harmful, by effecting chemical change
- A62D2101/20—Organic substances
- A62D2101/24—Organic substances containing heavy metals
-
- A—HUMAN NECESSITIES
- A62—LIFE-SAVING; FIRE-FIGHTING
- A62D—CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS
- A62D2101/00—Harmful chemical substances made harmless, or less harmful, by effecting chemical change
- A62D2101/40—Inorganic substances
- A62D2101/43—Inorganic substances containing heavy metals, in the bonded or free state
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Organic Chemistry (AREA)
- Metallurgy (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Manufacturing & Machinery (AREA)
- General Chemical & Material Sciences (AREA)
- Emergency Management (AREA)
- Business, Economics & Management (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Toxicology (AREA)
- General Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Processing Of Solid Wastes (AREA)
- Removal Of Specific Substances (AREA)
Abstract
The present invention is directed to a process of treating fly ash and/or fly ash leachate to immobilize heavy metals contained in such fly ash and/or fly ash leachate, which process comprises treating such fly ash and/or fly ash leachate with a soluble ferrous compound under alkaline conditions. This process may be conducted in the absence of any pH modification, mixing (in the sense of a physical blending with a solid material), drying or heating steps, making it practical for treatment of alkaline fly ash (and other coal combustion by-products) which is currently stored in landfills or wet ash lagoons,, particularly fly ash which has been recovered from flue gas streams treated with highly alkaline materials such as trona, bicarbonate or limestone and the like.
Description
FLY ASH AND FLY ASH LEACHATE TREATMENT
FIELD OF THE INVENTION
[0001] The present invention is directed to a process of treating fly ash and/or fly ash leachate to immobilize heavy metals contained in such fly ash and/or fly ash leachate, which process comprises treating such fly ash and/or fly ash leachate with a soluble ferrous compound under alkaline conditions.
BACKGROUND
FIELD OF THE INVENTION
[0001] The present invention is directed to a process of treating fly ash and/or fly ash leachate to immobilize heavy metals contained in such fly ash and/or fly ash leachate, which process comprises treating such fly ash and/or fly ash leachate with a soluble ferrous compound under alkaline conditions.
BACKGROUND
[0002] The generation of power from coal can result in a number of undesirable pollutants being placed into the environment. These pollutants may be released in a number of forms, including flue gases and fly ash. Many of the gases which may be produced as a result of coal combustion, such as oxides of nitrogen and sulfur, will react with water in the environment to produce acid rain. Such gases may also contain oxides of heavy metals including selenium, arsenic, vanadium and chromium which can cause problems in the environment. Fly ash, which constitutes fine solid particles which rise with such flue gas, typically contains oxides of such heavy metals as well.
[0003] Pursuant to environmental requirements, in the United States fly ash must be removed from flue gas before its discharge into the environment. Fly ash is typically removed from flue gas employing electrostatic precipitators or other particle filtration equipment. Such captured fly ash is generally stored at coal power plants or placed in landfills. Indeed, as is noted by Donahoe et al, Chemical Fixation of Trace Elements in Coal Fly Ash, 2007 World of Coal Ash, May 7-10, 2007, Covington, Kentucky, USA, more than two-thirds of such coal combustion products in the US are stored in dry landfills or wet lagoons; most of the older ash deposit sites are unlined and many are unmonitored. Therefore, heavy metals contained in such combustion products can create environmental concerns if it is leached through contact with rain water or other similar means.
[0004] In order to treat flue gases so to remove acid forming compounds such as SO2 and S03, many power plants treat flue gas with carbonate-containing materials such as trona, bicarbonate or limestone. Thus, for example, US Patents 7,531,154 and 7,854,911 disclose a process for removing SOx gases from a flue gas stream employing trona. While such systems are effective for removing sulfur oxides from flue gas, they can result in the production of fly ash which has increased amounts of heavy metals, particularly selenium, due to the extraction of such material from the flue gas stream as a consequence of the use of such an alkaline sorbent material.
[0005] The selenium present in such fly ash deposits is generally in the form of selenite (Se032-; or Se(IV)) and selenate (5e042-; or Se(VI)). As is discussed in US
Patent Application 2009/0130013, both selenite and selenate are soluble in water;
however, selenite can be removed from wastewater by co-precipitation with iron hydroxide at a pH in the 5.5 to 6.5 range. [Paragraph 00071. This publication discloses that the addition of iron to a limestone slurry flue gas desulfurization ("FGD") system, particularly a forced oxidation FGD system, may reduce the formation of selenate, and may result in the absorption or precipitation of reduced forms of selenium with iron hydroxide -- a reaction which favorably occurs at the pH at which FGD scrubbers typically operate (between approximately 5.5 and 6).
In this regard, it is noted that Disney et al, FGD Forced Oxidation Mechanism A
Pilot Plant Case Study, 2005 World of Coal Ash (WOCA), April 11-15, 2005, Lexington, Kentucky, USA state that the presence of unreacted lime or limestone in the feed slurry is a cost factor which must be controlled ... Depending upon feed chemistry, a pH increase (above 5.5) can quickly impede the oxidation chemistry." As they are used to desulfurize emissions as they are produced in a combustion reaction, FGD
processes are conducted at elevated temperatures (ranging from 1400 to 153 C
in Disney et al).
Patent Application 2009/0130013, both selenite and selenate are soluble in water;
however, selenite can be removed from wastewater by co-precipitation with iron hydroxide at a pH in the 5.5 to 6.5 range. [Paragraph 00071. This publication discloses that the addition of iron to a limestone slurry flue gas desulfurization ("FGD") system, particularly a forced oxidation FGD system, may reduce the formation of selenate, and may result in the absorption or precipitation of reduced forms of selenium with iron hydroxide -- a reaction which favorably occurs at the pH at which FGD scrubbers typically operate (between approximately 5.5 and 6).
In this regard, it is noted that Disney et al, FGD Forced Oxidation Mechanism A
Pilot Plant Case Study, 2005 World of Coal Ash (WOCA), April 11-15, 2005, Lexington, Kentucky, USA state that the presence of unreacted lime or limestone in the feed slurry is a cost factor which must be controlled ... Depending upon feed chemistry, a pH increase (above 5.5) can quickly impede the oxidation chemistry." As they are used to desulfurize emissions as they are produced in a combustion reaction, FGD
processes are conducted at elevated temperatures (ranging from 1400 to 153 C
in Disney et al).
[0006] Thus, processes which are effective to reduce selenate to selenite under the acidic pH conditions and high temperatures at which FGD processes are employed to treat flue gas may not be practical to treat alkaline fly ash deposits, particularly those which are highly alkaline due to treatment with trona or similar high carbonate materials. Specifically, such processes would require the addition of large amounts
7 of acid and heat to such fly ash deposits, which additions themselves are expensive and environmentally unfavorable.
[0007] US Patent Application 2010/0145130 proposes a method of stabilizing selenium in coal combustion products which comprises mixing such product with a sulfide compound (including FeS, an insoluble compound) followed by treatment with soda ash, nahcolite, trona, sodium sulfite and/or sodium hydroxide.
Although details of this treatment are not provided, it is apparent the addition of insoluble FeS
would require substantial physical mixing; while the addition of strongly basic materials to fly ash stored in landfills or ponds would be environmentally undesirable.
[0007] US Patent Application 2010/0145130 proposes a method of stabilizing selenium in coal combustion products which comprises mixing such product with a sulfide compound (including FeS, an insoluble compound) followed by treatment with soda ash, nahcolite, trona, sodium sulfite and/or sodium hydroxide.
Although details of this treatment are not provided, it is apparent the addition of insoluble FeS
would require substantial physical mixing; while the addition of strongly basic materials to fly ash stored in landfills or ponds would be environmentally undesirable.
[0008] Donahoe et al, Chemical Fixation of Trace Elements in Coal Fly Ash, World of Coal Ash, May 7-10, 2007, Covington, Kentucky, USA discloses a process for chemically fixing heavy metals contained in fly ash; however, such process requires a drying step (to permit oxidation to occur). Such a drying step is not practical in treating fly ash stored in wet ash lagoons or in landfills which are subject to periodic rainfall, dew condensation or other forms of moisture addition.
[0009] Consequently, there is a need for a process to reduce the leaching of heavy metals from alkaline fly ash, particularly fly ash deposited in wet ash lagoons or landfills which does not require the addition of pH modifiers which could be costly and environmentally undesirable, and which does not require commercially impractical mixing, drying or heating steps.
SUMMARY OF THE INVENTION
SUMMARY OF THE INVENTION
[0010] The present invention is directed to a process of treating fly ash and/or fly ash leachate to immobilize heavy metals contained in such fly ash and/or fly ash leachate, which process comprises treating such fly ash and/or fly ash leachate with a soluble ferrous compound under alkaline conditions. This process may be conducted in the absence of any pH modification, mixing (in the sense of a physical blending with a solid material), drying or heating steps, making it practical for treatment of alkaline fly ash (and other coal combustion by-products) which is currently stored in landfills or wet ash lagoons, particularly fly ash which has been recovered from flue gas streams treated with highly alkaline materials such as trona, bicarbonate or limestone and the like.
DETAILED DESCRIPTION OF THE INVENTION
DETAILED DESCRIPTION OF THE INVENTION
[0011] The present invention is directed to a process of treating fly ash and/or fly ash leachates to immobilize heavy metals contained in such fly ash and /or fly ash leachate, which process comprises treating such fly ash and/or fly ash leachate with a soluble ferrous compound under alkaline conditions without a subsequent drying step..
[0012] As is employed herein, the term "soluble ferrous compound" refers to an iron (II) compound having a solubility in water of at least 0.02 mole/L at 25 C;
and preferably having a solubility in water of at least 0.2 mole/L at 25 C.
Particularly preferred soluble ferrous compounds include ferrous chloride and ferrous sulfate, including hydrated forms of these compounds such as FeSO4.7H20 and FeC12.4H20.
and preferably having a solubility in water of at least 0.2 mole/L at 25 C.
Particularly preferred soluble ferrous compounds include ferrous chloride and ferrous sulfate, including hydrated forms of these compounds such as FeSO4.7H20 and FeC12.4H20.
[0013] Further, as is employed herein, the term "fly ash leachate" refers to water which has come into contact with fly ash and which contains dissolved heavy metals as a result of such contact. The term "immobilize" refers to the complexing of a heavy metal such that it is no longer soluble in aqueous solutions.
[0014] As is employed herein, the term "heavy metal" means transition metals, and other metals and metalloids in Period 4 or higher of the Periodic Table. Heavy metals which are environmentally undesirable and which may be immobilized by the process of this invention include selenium, arsenic, vanadium, chromium, cadmium, lead, nickel and mercury. The process is particularly useful for the immobilization of selenium, arsenic, vanadium, and chromium; and is especially useful for the immobilization of selenium.
[0015] The fly ash to be treated may be located in storage areas including dry landfills or wet ash lagoons, or it may be present at combustion locations after collection by electrostatic precipitators or other means. The fly ash may be mixed with other coal combustion products. Although the fly ash to be treated may have any pH above 7, the process of this invention is particularly suitable for the immobilization of highly alkaline fly ash (typically having a pH of 8 or more;
or even as high as 10 or more) produced by the desulfurization systems which employ highly basic materials such as trona, bicarbonate, limestone or the like.
or even as high as 10 or more) produced by the desulfurization systems which employ highly basic materials such as trona, bicarbonate, limestone or the like.
[0016] The soluble ferrous compound may be added to the fly ash in solid form where practical, such as in the treatment of ash lagoons; or may be added in liquid form (dissolved in an aqueous solution) to treat dry landfills or similar locations.
With respect to the treatment of ponds, one preferred embodiment is to add a solution of the soluble ferrous material to the slurry containing the fly ash as it enters the holding pond, as this would provide desirable mixing of the solution into the pond water.
With respect to the treatment of ponds, one preferred embodiment is to add a solution of the soluble ferrous material to the slurry containing the fly ash as it enters the holding pond, as this would provide desirable mixing of the solution into the pond water.
[0017] It has been surprisingly found that the addition of a soluble ferrous compound will immobilize heavy metals present in fly ash such that they do not leach out into ground water, without the need for pH adjustment or heating or drying steps. Further, because soluble compounds are employed, dry landfills containing fly ash can be treated without the need for the extensive physical mixing required if non-soluble compounds were employed. The properties render the present process suitable for the in situ treatment of both fly ash and fly ash leachate.
[0018] The amount of soluble ferrous compound added will depend upon the amount of heavy metal present in the fly ash and/or fly ash leachate to be treated. In general, when leachate is treated, between 0.5 grams of Fe(II) per liter of leachate and 15 grams of Fe(II) per liter of leachate will be employed; with amount of from 2 to 9 more typically being used. In general, when fly ash is to be treated, generally between 0.1 weight percent and 15 weight percent Fe(II) is employed (based upon the weight of the fly ash to be treated); typically between 0.5 weight percent and 10 weight percent of Fe(II) is applied.
[0019] The following Examples are intended to further illustrate the invention, but are not intended to limit the scope of the invention in any manner.
EXAMPLES
Example 1
EXAMPLES
Example 1
[0020] 1000 grams of deionized water was added to 100 grams of fly ash (containing 88 weight percent coal ash, 6.4 weight percent Na2SO4, 1.9 weight percent Na2CO3, and 3.7 weight percent NaHCO3) and stirred for 24 hours. The final solution was at pH 10.3. 11 grams of FeSO4.7H20 (i.e., 2.2 g Fe/L) was added dry and the mixture was stirred for a few minutes until all of the Fe salt was dissolved, then stirring was stopped. Aliquots of the solution were withdrawn at the time intervals indicated in the table, filtered, then analyzed for selenium, arsenic and vanadium content. The results of such testing are shown in Table 1 below:
Table 1 Treatment Time Percent Se Percent As Percent V
(Days) Removal from removal from Removal from Solution Solution Solution 0.083 60 100 100
Table 1 Treatment Time Percent Se Percent As Percent V
(Days) Removal from removal from Removal from Solution Solution Solution 0.083 60 100 100
21 68 100 100 [0021] The above results indicate that a significant amount of Se is removed from the leachate within a few hours of treatment and additional removal occurs over time. As and V are completely removed from solution within a few hours.
Example 2
Example 2
[0022] 1000 grams of deionized water was added to 100 grams of fly ash (containing 51.5 weight percent bituminous coal ash, 10.7 weight percent Na2SO4, 30.6 weight percent Na2CO3, 7.2 weight percent NaHCO3) and stirred for 24 hours.
The final solution was at pH 10.1. The leachate was separated from the solids by filtration, then 30 grams of FeC12.4H20 (i.e., 8.4 g Fe/L) was added dry and the mixture was stirred for a few minutes until all of the Fe salt was dissolved, then stirring was stopped. Aliquots of the solution were withdrawn at the time intervals indicated in the table, filtered, then analyzed for selenium, arsenic, vanadium and chromium content. The results of such testing are shown in Table 2 below:
Table 2 Treatment Percent Se Percent As Percent V Percent Cr Time (Days) Removal from Removal from Removal from Removal from Solution Solution Solution Solution 1 40 100 Not measured Not measured
The final solution was at pH 10.1. The leachate was separated from the solids by filtration, then 30 grams of FeC12.4H20 (i.e., 8.4 g Fe/L) was added dry and the mixture was stirred for a few minutes until all of the Fe salt was dissolved, then stirring was stopped. Aliquots of the solution were withdrawn at the time intervals indicated in the table, filtered, then analyzed for selenium, arsenic, vanadium and chromium content. The results of such testing are shown in Table 2 below:
Table 2 Treatment Percent Se Percent As Percent V Percent Cr Time (Days) Removal from Removal from Removal from Removal from Solution Solution Solution Solution 1 40 100 Not measured Not measured
[0023] The above results indicate that a significant amount of Se is removed from the leachate within 1 day of treatment and additional removal occurs over time. As, V, and Cr are completely removed within 1 week.
Claims (16)
1. A process of treating fly ash and/or fly ash leachate to immobilize heavy metals contained in such fly ash and/or fly ash leachate, which process comprises treating such fly ash and/or fly ash leachate with a soluble ferrous compound under alkaline conditions without a subsequent drying step..
2. The process of claim 1 wherein the fly ash is present in a solid landfill.
3. The process of claim 1 wherein the fly ash is located in an ash lagoon.
4. The process of claim 1 wherein the fly ash was produced employing at least one member from the group consisting of trona, bicarbonate and limestone as a desulfurant.
5. The process of claim 4 wherein the fly ash was produced employing trona as a desulfurant.
6. The process of claim 1 wherein the fly ash has a pH of 8 or higher.
7. The process of claim 6 wherein the fly ash has a pH of 10 or higher.
8. The process of claim 1 wherein the soluble ferrous compound is ferrous sulfate or a hydrated form thereof.
9. The process of claim 1 wherein the soluble ferrous compound is ferrous chloride or a hydrated form thereof.
10. The process of claim 1 wherein such process is conducted in situ.
11. The process of claim 1 wherein the heavy metal is selected from the group consisting of selenium, arsenic, vanadium, chromium, cadmium, lead, nickel and mercury.
12. The process of claim 11 wherein the heavy metal is selected from the group consisting of selenium, arsenic, vanadium, and chromium.
13. The process of claim 12 wherein the heavy metal is selenium.
14. The process of claim 12 wherein the heavy metal is arsenic.
15. The process of claim 1 wherein fly ash leachate is treated and between 0.5 grams of Fe(II) per liter of leachate and 15 grams of Fe(II) per liter of leachate is employed.
16. The process of claim 1 wherein fly ash is treated and between 0.1 weight percent and 15 weight percent Fe(II) is employed, based upon the weight of the fly ash to be treated.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US201261650228P | 2012-05-22 | 2012-05-22 | |
| US61/650,228 | 2012-05-22 | ||
| PCT/US2013/040495 WO2013176907A1 (en) | 2012-05-22 | 2013-05-10 | Fly ash and fly ash leachate treatment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2874325A1 true CA2874325A1 (en) | 2013-11-28 |
Family
ID=49621763
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA2874325A Abandoned CA2874325A1 (en) | 2012-05-22 | 2013-05-10 | Fly ash and fly ash leachate treatment |
Country Status (3)
| Country | Link |
|---|---|
| US (1) | US20130315804A1 (en) |
| CA (1) | CA2874325A1 (en) |
| WO (1) | WO2013176907A1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2015187778A1 (en) * | 2014-06-04 | 2015-12-10 | Solvay Sa | Stabilization of at least one heavy metal contained in a sodic fly ash using a water-soluble source of silicate and a material containing calcium and/or magnesium |
| US10024534B2 (en) | 2014-06-04 | 2018-07-17 | Solvay Sa | Stabilization of sodic fly ash of type F using calcium-based material |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9550084B2 (en) * | 2012-05-23 | 2017-01-24 | University Of Wyoming | Removal of elements from coal fly ash |
| US8945247B1 (en) * | 2013-02-08 | 2015-02-03 | VRC Techonology, LLC | Methods and apparatus for the improved treatment of carbonaceous fuel and/or feedstocks |
| WO2017143007A1 (en) * | 2016-02-18 | 2017-08-24 | Southern Research Institute | Composition and method related to the recovery of germanium and rare earth elements |
| US11721448B1 (en) | 2020-07-09 | 2023-08-08 | National Technology & Engineering Solutions Of Sandia, Llc | Radioactive waste repository when contacted by water provides borates that absorb neutrons |
| CN114956379B (en) * | 2022-05-30 | 2023-08-22 | 南京理工大学 | Method for realizing arsenic fixation in liquid by utilizing fly ash to form safe landfill |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3984312A (en) * | 1973-04-23 | 1976-10-05 | Industrial Resources, Inc. | Process for insolubilizing potentially water pollutable wastes from sodium or ammonium type sulfur dioxide air pollution control systems |
| ZA883753B (en) * | 1987-06-18 | 1989-03-29 | Bethlehem Steel Corp | Process for chemical stabilization of heavy metal bearing dusts and sludge,such as eaf dust |
| JPH08309314A (en) * | 1995-05-15 | 1996-11-26 | N K K Plant Kensetsu Kk | Treatment method for fly ash containing heavy metal |
| JPH08309310A (en) * | 1995-05-18 | 1996-11-26 | Jgc Corp | Treatment method for incinerated fly ash containing heavy metal |
| US6053857A (en) * | 1998-05-15 | 2000-04-25 | Conversion Systems, Inc. | Immobilization of thallium during electric arc furnace dust treatment |
| US7544636B2 (en) * | 2004-03-04 | 2009-06-09 | The Regents Of The University Of California | Treated bottom ash medium and method of arsenic removal from drinking water |
| US7736291B2 (en) * | 2006-03-25 | 2010-06-15 | Forrester Keith E | Method for stabilization of heavy metals and odor control with dicalcium phosphate dihydrate powder |
| US20100145130A1 (en) * | 2008-12-09 | 2010-06-10 | Mccullough Thomas P | Treatment Method for Stabilizing Selenium in Coal Combustion Ash |
| US9550084B2 (en) * | 2012-05-23 | 2017-01-24 | University Of Wyoming | Removal of elements from coal fly ash |
-
2013
- 2013-05-10 WO PCT/US2013/040495 patent/WO2013176907A1/en active Application Filing
- 2013-05-10 US US13/891,375 patent/US20130315804A1/en not_active Abandoned
- 2013-05-10 CA CA2874325A patent/CA2874325A1/en not_active Abandoned
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2015187778A1 (en) * | 2014-06-04 | 2015-12-10 | Solvay Sa | Stabilization of at least one heavy metal contained in a sodic fly ash using a water-soluble source of silicate and a material containing calcium and/or magnesium |
| US10024534B2 (en) | 2014-06-04 | 2018-07-17 | Solvay Sa | Stabilization of sodic fly ash of type F using calcium-based material |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2013176907A1 (en) | 2013-11-28 |
| US20130315804A1 (en) | 2013-11-28 |
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