• WOA1

    a process for the treatment of a solution containing at least ferric ions, and one or more metal values, said process including the step of maintaining a controlled concentration of ferric ions in...

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  • Emission reduction process for dechlorinating flue‐gas desulfurization ...

    due to these characteristics, the use of naturally mined raw gypsum material in appliions typically involves multiple processing procedures and steps. 1 however, synthetic gypsum is highly similar to naturally mined gypsum 2; hence, specific types of synthetic gypsum have replaced natural gypsum in several industries such as cement plants, .

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  • What is FGD Gypsum

    Many different products from the various FGD processes, primarily: – Lime/limestone force oxidized (LSFO) = Calcium sulfate dihydrate (gypsum) – Lime/limestone unoxidized = Calcium sulfite – Fluidized bed ash and dry scrubbers = mixtures of char/fly ash and spent bed material or sorbent containing CaO, CaSO 4, CaSO

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  • TREATMENT OF ACID MINE DRAINAGE USING MAGNESIUM .

    CiteSeerX Document Details (Isaac Councill, Lee Giles, Pradeep Teregowda): Acid drainage from mining activities is of major environmental concern in South Africa. These effluents require neutralisation and metal removal prior to release to public watercourses. A novel process is proposed whereby magnesium hydroxide is being used for neutralization of free acid and .

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  • Nanomaterials | Free FullText | The Generation Process, Impurity ...

     · The main reaction equation is as follows [ 12 ]: Ca 5 F (PO 4) 3 + 5H 2 SO 4 + 10H 2 O = 5CaSO 4 ·2H 2 O + 3H 3 PO 4 + HF↑ (1) For every t phosphoric acid produced, – t PG is produced [ 13, 14, 15, 16, 17 ]. At present, the annual production of PG in the world is up to 200 million tons, and about 70 million tons in China.

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  • Designing a Mine Water Treatment Facility to Remove Sulfate

    processes at many mining operations. Where they apply, sulfate discharge standards in the United States typically range between 250 and 1,000 mg/L, with proposals in certain areas to apply sulfate discharge standards as low as 10 mg/L. The presentation highlights the design of a full–scale mine water treatment facility to remove sulfate in AMD–impacted waters at a mine in .

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  • Gypsum amendment and seasonal variability: effect on soil quality ...

    Gypsum Production Gypsum used in the experiment was produced by a precipitation process from the concentrate of a reverse osmosis (RO) water treatment plant in which impacted water from the Apensu pit was pumped at a nameplate capacity of 50 L/s to .

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  • Case study modelling for an ettringite treatment process

    Conventionally, lime precipitation reduces sulphate concentrations through the precipitation of gypsum. At gypsum equilibrium, which is typically only approached by lime precipitation technologies, the sulphate concentration is still well above limits proposed by discharge guidelines. Therefore, further treatment is required.

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  • An Aspen Model for the Treatment of Acid Mine Water

    gypsum. The precipitation of gypsum is not pH dependant, therefore the pH of the water exiting stage 2 will be the same as that entering stage 2, namely This precipitated gypsum is thickened and filtered, and leaves the process as waste or as a byproduct, depending on the specific situation. Part of the precipitated gypsum is returned to ...

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  • a process of minning gypsum

     · mining gypsum process. Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO 4 2H 2 O It is widely mined and is used as a fertilizer, and as the main constituent in many forms of plaster, blackboard chalk and wallboard...

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  • Sulfate Removal Technologies A Review

     · GYPCIX is a fluidized bed ion exchange process developed in South Africa to remove sulfate from water that is close to gypsum saturation, so it could be used as a polishing step after lime precipitation. It is the historic predecessor to the SulfIX process, which maintains the IX resin in the same vessel to minimize attrition from resin handling.

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  • Nickel Solvent Extraction Technology

    Use of MgO as the base in the hydroxide precipitation step minimizes the formation of gypsum in downstream processing. 5. The nickel concentration of the ammonia leach solution can be controlled to minimize the size of the nickel SX plant. Typically, the ammonia leach solution has a concentration of 10 – 20 g / I nickel. 6.

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  • Drinking Water from Mine Water Using the HiPrO® Process

    Key Wordsacid mine drainage, gypsum precipitation Background optimum Coal mine comprises numerous defunct, active and future mining sections. The mine is situated in Pullenshope, mpumalanga, south Africa and is a multiproduct mine with a contract to supply the nearby Hendrina Power station with coal until 2018.

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  • A Continuous Process for RO Concentrate Desupersaturation

     · It was found that CCESP treatment of the PRO concentrate with mM lime enabled up to 68% removal of the residual antiscalant. Subsequent gypsum seeded precipitation (initial seed loading of 240 g/L gypsum) reduced the PRO concentrate gypsum supersaturation index (SIg) level from to nearly unity.

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  • What is the limestone's mining process?

     · They are "mined" in a process known as "quarrying." This process varies depending on the use of the product. If it is to be made into cement, it is needed in small pieces so that it can be ground and calcined. In this case, the rock has holes drilled in it which are filled with explosive and they are fired, breaking the rock into small pieces.

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