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Phosphogypsum (PG) is a type of synthetic gypsum generated during the production of phosphoric acid. Each ton of phosphoric acid generates 5 tons of phosphogypsum. ... The use of PG up to 50% meets the limits required for index I, with a radioactivity equivalent to radio-226 and a concentration of radon-222. The data found …
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Phosphogypsum has physical properties that make it useful as a sub-base for roadways, parking lots, and similar construction. A radiological evaluation, to determine exposures to workers mixing this material with a stabilizing agent (portland cement), was performed at a South Louisiana phosphoric acid chemical plant. Measurements of the 226Ra ...
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Phosphogypsum contains substantial quantities of P, which can be beneficial if large amounts of gypsum are applied. The levels of the other elements in the materials are so low that they are of little importance. Phosphogypsum from Florida contains 226 Ra and gives off radon (222 Rn) gas, which poses a potential health hazard (Mays and Mortvedt ...
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1. Introduction. Phosphogypsum (PG), a significant Technologically Enhanced Naturally Occurring Radioactive Material (TENORM) (IAEA, 2003), is a by-product of …
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Florida lawmakers want to use radioactive material phosphogypsum to pave roads Phosphogypsum, a byproduct in the fertilizer industry, contains uranium and radium — and as the EPA notes, it also ...
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EPA defines Phosphogypsum. "...as a radioactive waste product that results from processing phosphate ore to make phosphoric acid that is later used in fertilizer. …
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Phosphogypsum stacks originating from the processing of phosphate rock contain small amounts of radionuclides, such as 226Ra. ... geochemistry in Mexico 13, and radionuclide transport in Germany 14.
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Global food supplies currently depend on producing inorganic P fertilisers from a finite reserve of rock phosphate (RP). P fertilisers are themselves significant pollutants but their production from RP also leaves a phosphogypsum (PG) by-product that is sufficiently radioactive that its reuse is restricted. PG is mostly accumulated in open 'stacks' that …
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Radioactive elements, most notably 226 Ra, 232 Th, 4 0 K result in the typical radioactivity indexes (I = (Ra/300) + (Th/200) + (K/3000)) of 1.33–2.59 for s-PG and the mixed PG (m-PG and s-PG). m-PG (particularly m-PG from Russia and some PG from China) typically shows relatively low radioactivity indexes of 0.24–0.45. m-PG and also …
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Produced in significant quantities, the material is considered a waste in the US due to radioactivity, where the primary means of management is storage in "stacks." But around the world, phosphogypsum is increasingly being utilized in beneficial reuse applications, with research around the topic growing. How Phosphogypsum is Produced
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A measurement of the radioactivity content of phosphate ore material, phosphatic fertilizer (superphosphate), and by-product phosphogypsum in the Abu-Zaabal phosphate plant, Egypt, has been carried out. According to the results of gamma-ray spectroscopy analysis, 238U was found in concentrations of …
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The concentration of metallic trace elements (Cr, Pb, Ni, Zn, Cu) in raw phosphogypsum ranged between 0.2 and 243 ppm, while its radioactivity reached 970 Bq/kg for Ra-226.
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Most phosphogypsum is stockpiled while lesser quantities are recycled or dumped into water. Phosphogypsum is primarily CaSO 4 ·2H 2 O, but also contains impurities of …
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Research hotspots and trends of comprehensive utilization of phosphogypsum: Bibliometric analysis. Zhongqi Wei, Zhengbin Deng, in Journal of Environmental Radioactivity, 2022. Abstract. Phosphogypsum is a by-product of the phosphate fertilizer industry. It is generally treated by stacking, which not only causes environmental …
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Radioactive elements, most notably 226 Ra, 232 Th, 4 0 K result in the typical radioactivity indexes (I = (Ra/300) + (Th/200) + (K/3000)) of 1.33–2.59 for s-PG …
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The radiological impact of this radioactivity, varies with the mineralogical nature of the phosphates (Table 2) (Scholten & Timmermans, 1996) and requires a special care, especially in Morocco where these are important mines of phosphates and phosphogypsum.This country is contributing about two-thirds of the phosphates …
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DOI: 10.1016/j.jenvrad.2022.106828 Corpus ID: 246594315; Radioactivity in Future Phosphogypsum: New predictions based on estimates of 'Peak P' and rock phosphate resources. @article{Willey2022RadioactivityIF, title={Radioactivity in Future Phosphogypsum: New predictions based on estimates of 'Peak P' and rock phosphate …
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Rashad A.M. Potential use of phosphogypsum in alkali-activated fly ash under the effects of elevated temperatures and thermal shock cycles. J. Clean. Prod. 2015; 87:717–725. [Google Scholar] Reijnders L. Cleaner phosphogypsum, coal combustion ashes and waste incineration ashes for application in building materials: a review. Build. …
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Abstract. Phosphogypsum (PG: CaSO 4 ·2H 2 O) is a waste product generated by the phosphate industry. World production of this waste exceeds 200 million tonnes per year. PG, discharged into the sea, watercourses or in wilderness stocks, contains toxic elements harmful to ecosystems and human health, including heavy …
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Phosphogypsum, a waste product from manufacturing fertilizer, emits radon, a radioactive gas. It also contains the …
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This study contributes to sustainable construction practices by exploring the use of phosphogypsum, a commonly discarded byproduct, in the production of recycled aggregates. Addressing both environmental and economic aspects of sustainability, we investigate the feasibility of employing phosphogypsum as a primary raw material, in …
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Abstract. Phosphogypsum (PG: CaSO 4 ·2H 2 O) is a waste product generated by the phosphate industry. World production of this waste exceeds 200 million tonnes per year. PG, discharged into the sea, …
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Journal of Environmental Radioactivity 54: 231-242. Google Scholar Beretka, J. (1990) The current state of utilization of phosphogypsum in Australia. In: Proceedings of the Third International Symposium on Phosphogypsum, Orlando, FL, FIPR Pub. No. 01-060-083, December 1990, vol. II 394-401. Google Scholar
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Appendix 5 to Revised Request for Approval of Additional Uses of Phosphogypsum (pdf) (87.1 KB, December 2019) Report on recent measurements of PG radioactivity level in U.S. stacks. Appendix 6 to Revised Request for Approval of Additional Uses of Phosphogypsum (pdf) (786.4 KB, December 2019)
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We evaluated the suitability of phosphogypsum from the Lowveld region of South Africa (LSA), for the manufacturing of building materials, with reference to (1) the National Nuclear Regulator Act 47 of 1999 and (2) the radioactivity associated risks as quantified in terms of the external and internal hazard indices, the activity concentration index and the radium …
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Phosphogypsum (PG), the main industrial by-product of phosphate fertilizer industry, primarily consists of calcium sulfate dihydrate. However, it contains various impurities with variable quantities depending on the origin of the phosphate rock. ... The radioactivity varies by phosphate rock type and is primarily caused by the U-238 and …
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Phosphogypsum (PG) is a by-product produced during the wet process of phosphoric acid (H3PO4) production from natural phosphate rocks. Approximately 4–6 tons of PG is produced per ton of ...
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Despite the radioactivity known to be contained in PG, the radiation dose resulting from the use of phosphogypsum piles, and received by the workers, is negligible compared Table 3. radioactive ...
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It has only been in recent years that the question of radioactivity has been raised and this question now influences every decision relative to potential use in building products in this country. Phosphogypsum utilization has evolved along three broad use groupings: (1) Chemical raw material (2) Agricultural applications (3) Construction ...
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Phosphogypsum (PG) is a by-product produced during the wet process of phosphoric acid (H3PO4) production from natural phosphate rocks. Approximately 4–6 tons of PG is produced per ton of phosphoric acid production, where worldwide PG generation exceeds 300 million tons annually. The vast majority of produced PG is discarded …
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