Petition to Reconsider Phosphogypsum in Roads
Petition to Reconsider EPA's PG Approval ‐6‐ Phosphogypsum is the radioactive waste from wet-process phosphoric acid production, the intermediate feedstock of granular and liquid ammonium phosphate fertilizers.17 Phosphogypsum contains high concentrations of radioactive materials, particularly radium and uranium.
Phosphogypsum circular economy considerations: A critical …
1. Introduction. Circular economy considerations are gaining more and more momentum among practitioners and scholars (Corona et al., 2019; Kirchherr et al., 2017) putting pressure on the extractive industries to also move away from a linear economy model to a more circular one.The nature of mining obviously makes this challenging and …
Frontiers | An Eco-Friendly Phosphogypsum-Based …
Phosphogypsum, solid waste from phosphoric acid production, is released at a rate of 170 million tons per year and is expected to accumulate over 7 billion tons by …
E-DOCKET: EPA-HQ-OAR-2020-0442
disposition of the phosphogypsum or any product in which the phosphogypsum is incorporated." In a Federal Register notice associated with amendments to this rule, the EPA referred an individual lifetime risk of fatal cancer risk of approximately 3×10-4 as a threshold for approving uses of phosphogypsum. (57 FR …
Preparation of gypsum with high purity and …
Abstract. Phosphogypsum (PG) is a solid waste product generated during wet-process phosphoric acid production. Various impurities considerably reduce the purity, whiteness, and application range ...
Piney Point in Manatee shows why the EPA needs to crack …
Phosphogypsum and process wastewater are produced from the processing of strip-mined phosphate ore into phosphoric acid, a fertilizer component. For every ton of phosphoric acid produced, you get ...
Bioavailability and mobility of trace metals in phosphogypsum from
Phosphogypsum (PG) is a by-product from the phosphate fertilizer industries. ... 1986, Witkamp and Van Rosmalen, 1988). Selenium may be adsorbed on surfaces of iron oxides (Geering et al., 1968). ... The geochemistry of major and trace elements in the agricultural terrain of South Viet Nam. J. Geochem. Explor., 66 (1–2) (1999), pp. 407-411.
Nghiên cứu thành phần bã thạch cao phosphogypsum, tách …
TÓM TẮT Thành phần bã thạch cao phosphogypsum của quá trình công nghệ dihydrat phân hủy quặng apatit Lào Cai với axit sunfuric chủ yếu là thạch cao chiếm 74,75-77,7%, P 2 O 5 còn trong bã từ 1,48-4,83%, F là 0,6-0,67%, SiO 2 chiếm 0,49-14,29 % và tạp chất hữu cơ và nhiều tạp chất khác. . Nghiên cứu độ hòa tan của các tạp ...
Study of the physical-chemical properties of the …
Phosphogypsum (PG) is a calcium sulphate dihydrate and a by-product of the phosphate fertilizer industry. It is produced in huge quantities (300 MT/year), but only 15% of the PG produced is recycled.
Piney Point leak spotlights phosphogypsum stacks in Florida
Phosphogypsum stacks are located in four counties in Florida including Polk, Hillsborough, Manatee, and Hamilton counties, according to the Florida Department of Environmental Protection. Florida ...
A new route to synthesize calcium carbonate …
3.2.Selectionofadditives Therearemanyadditivesthatplaykeyrolesinthenucleationprocessandhavesignificanteffectsonthe morphologyandevencrystalshapeoftheproduct[24–27 ...
Fate and transport of radioactive gypsum stack …
Phosphogypsum stacks originating from the processing of phosphate rock contain small amounts of radionuclides, such as 226Ra. ... Daljit Sandhu, Arvind Singh, Steven J. Duranceau, Boo Hyun Nam ...
(PDF) Purification of South African phosphogypsum for …
Van der Merwe and Strydom ... Phosphogypsum, the by-product of phosphoric acid industry, consists of CaSO4.2 H2O and contains some impurities such as P2O5, F and organic substances. These ...
Potential Uses of Phosphogypsum and Associated Risks: …
4-32 4-17 Risk assessment results for Scenario 10 - use of phosphogypsum in a concrete road surface (clay) T . .4-33 4-18 Risk assessment results for Scenario 11. - use of phosphogypsum in a concrete road surface (sand) 4-34 4-19 Risk assessment results for Scenario 12 - use of phosphogypsum in R&D activities 4-36 4-20 The estimated total …
TENORM: Fertilizer and Fertilizer Production Wastes | US EPA
Side view of phosphogypsum stack. Phosphate production generates huge amounts of phosphogypsum wastes, nearly 48 million MTs in 1988 alone. Industry estimates that 5.2 tons of phosphogypsum is produced for every ton of phosphoric acid. Phosphogypsum has little market value and is transferred as a slurry to waste piles …
Petition to Reconsider Phosphogypsum in Roads
Petition to Reconsider EPA's PG Approval ‐6‐ Phosphogypsum is the radioactive waste from wet-process phosphoric acid production, the intermediate feedstock of granular and liquid …
Utilization of Phosphogypsum to Prepare High-Purity CaCO3
High-purity CaCO3 via a facile two-step dissolution–carbonation coprecipitation procedure using NH4Cl, NH4OH, and CO2 with phosphogypsum (PG) as the raw material was successfully produced in the present work. The impact of different experimental parameters on dissolution and carbonation processes was discussed …
Imminent Failure of Phosphogypsum Stack in Tampa Bay …
ST. PETERSBURG, Fla.— Manatee County officials have issued evacuation orders for the area surrounding Florida's Piney Point in anticipation of the imminent catastrophic collapse of a phosphogypsum stack retention pond holding up to 700 million gallons of wastewater. It has been reported that 22,000 gallons a minute are being …
Preparation of CaCO3 nano and microparticles from …
Currently, the amount of Phosphogypsum waste is up to 5.6 million tons/year. It mainly contains gypsum, a potential material for carbon dioxide sequestration by mineral carbonation.[2] However, phosphogypsum has potential risks for the environment due to the presence of many toxic substances such as HF, H 2 SO 4, H 3 …
Phosphogypsum and the EPA Ban
In 1989, stacking of phosphogypsum in the U.S. became a legal necessity when the U.S. Environmental Protection Agency (EPA) banned its use. In 1992, this rule was modified to allow the use of phosphogypsum with an average radium-226 concentration of less than 10 picocuries/gram (pCi/g) for agricultural application as a soil amendment.
Sustainable Approach for Recovery of Sulfur from …
By heating the raw phosphogypsum to 105 °C, the humidity obtained is 20.8%, while it is 37.5% at 220 °C. The water of crystallization is then 16.7%. The second method of dehydration was carried out using differential scanning calorimetry (DSC), high-pressure DSC, −120 to 500 °C, Model 90/39324 (Setaram).
Study on the Properties of Waste Apatite Phosphogypsum …
Abstract This paper presents the results of the study on chemical and the physical properties of waste phosphogypsum (PG) of apatite origin from the former chemical plant Wizow, Poland which are important for further processing and economic use. The research was carried out to verify whether the waste might be useful as a raw …
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phosphogypsum contains approximately 3% of potassium phosphate, sodium, aluminum and ferrum as well as phosphoric acid and salts of heavy metal. Today in Russia phosphogypsum is formed at 12 plants [1 -4]. Annual waste release is equal to more than 10 million tons. Phosphogypsum stacks cover large territories of plowing …
PHOSPHOGYPSUM ANALYSIS: TOTAL CONTENT AND …
phosphogypsum is classified as TENORM (Technologically Enhanced Naturally Occurring Radioactive Material), that is, a solid waste containing naturally occurring radioactive elements from the rock matrix. Environmental impact studies should assess the existing site and conditions and evaluate the anticipated impacts on the environment itself by ...
Pages 417-535, Volume 59, Number 4, August 2021 …
functional foods from Viet Nam by UPLC-MS/MS Tran Quang Hieu *, Phan Pham Huynh Vi, Pham Kim Phuong, Lai Thi Kim Bien, Nguyen Thanh Tan 475 Triterpenoids from Macrosolen bidoupensis Tagane & V.S. Dang whole plant Le Kieu Hung, Huynh Bui Linh Chi, Pham Nguyen Kim Tuyen, Nguyen Thi Thuy Trang, Dang Van Son, Tran Thi Ngoc …
Improving soil fertility with lime and phosphogypsum
In tropical no-till systems, applying lime (L) and phosphogypsum (PG) on the soil surface may be a potential strategy for reducing soil acidification and improving soybean root growth, thereby enhancing plant nutrition and physiological responses and, in turn, crop resistance to dry spells. This study evaluated the impact of long-term (17 years) surface …
Phosphogypsum and Wastewater RCRA/TSCA …
EPA Receives Petition Seeking RCRA and TSCA Regulatory Action for Phosphogypsum and Process Wastewater. On February 8, 2021, the U.S. Environmental Protection Agency (EPA) received a …
Preparation of Nano-CaCO3 from Phosphogypsum by Gas–Liquid–Solid
Nano-CaCO3 was prepared from phosphogypsum (PG) through reactive crystallization in the gas (CO2)–liquid (NH3·H2O)–solid (PG) three-phase system. The effects of temperature, CO2 flow rate, and reaction time on the CaCO3 particle size distribution (PSD) were investigated. The results show that PG-derived nano-CaCO3 with …
Phosphogypsum Factsheet
WHAT IS PHOSPHOGYPSUM? Phosphogypsum is the radioactive waste from processing phosphate ore into phosphoric acid which is predominantly used in fertilizer. In addition to …
Radioactive waste roads in Florida: Phosphogypsum can be …
Here, signs block a roadway in Boca Raton during a construction project in 2021. Florida is another step closer to paving its roads with phosphogypsum — a radioactive waste material from the ...
