Effects of phosphogypsum, superphosphate, and …
This study investigated the effects of phosphogypsum, superphosphate, and dicyandiamide on gaseous emission and compost quality during sewage sludge composting. Results showed that phosphogypsum reduced ammonia (NH3) and methane (CH4) emissions but increased nitrous oxide (N …
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EPA Approves Use of Phosphogypsum in Road Construction
By finding a new way to use phosphogypsum, EPA is helping create a sustainable path to improve the environment while allowing for responsible reuse and …
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Effect of phosphogypsum and dicyandiamide as additives …
A laboratory scale experiment of composting in a forced aeration system using pig manure with cornstalks was carried out to investigate the effects of both phosphogypsum and dicyandiamide (DCD, C 2 H 4 N 4) as additives on gaseous emissions and compost quality.Besides a control, there were three amended …
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Investigating effects of phosphogypsum disposal practices …
The three phosphogypsum reuse practices enhanced carbon emission intensity to varying degrees compared with Scenario 1 due to the increasing fossil energy use. Those phosphogypsum reuse practices, based on nonrenewable resources/energy source inputs, caused conflict between waste reduction and carbon emission reduction.
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Effects of phosphogypsum and superphosphate on compost …
Phosphogypsum and superphosphate had no negative effects on compost maturity, although superphosphate inhibited the temperature rise in the first few days. The addition of phosphogypsum and superphosphate drastically reduced CH4 emissions (by 85.8% and 80.5%, respectively) and decreased NH3 emissions (by 23.5% and 18.9%, respectively).
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Valorization of phosphogypsum in Supersulfated Cement …
Phosphogypsum is a by-product from the production of phosphoric acid. In this process, the raw phosphate is treated by sulfuric acid and, besides the main product which is phosphoric acid (H3PO4), gypsum and a small quantity of hydrofluoric acid are obtained. For every tonne of phosphoric acid made, about three tonnes of phosphogypsum …
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A review on the environmental impact of phosphogypsum and …
The PG production in a country commonly correlates with its phosphoric acid production, and thus with its number of phosphate deposits. In 2012, around 250 million tons of PG were produced with the largest producers being Morocco (32%), China (25%), USA (18%), India (5%), ( Layr and Hartlieb, 2019 ).
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Phosphogypsum: potential uses and problems – …
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 …
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Regulating sulfur migration and transformation in low water …
The paper aims to clarify the regulation mechanism of sulfur migration and transformation in a low water-binder ratio system incorporating phosphogypsum aggregate (LWC-PG). Firstly, the combination of S-containing adhesive material and phosphate gypsum aggregate can reduce the migration of sulfate ions (SO 4 2−) in the phosphate …
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Exploring the potential reuse of phosphogypsum: A waste …
The management of solid mine waste requires a detailed characterization and a full understanding of the reparation of elements in the origin rock and their distribution in the waste matrix (Elghali et al., 2018).It is now generally acknowledged that the distribution, mobility, availability, and toxicity of chemical elements are determined not …
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Effects of Dicyandiamide, Phosphogypsum, and …
The addition of phosphogypsum and superphosphate drastically reduced CH4 emissions (by 85.8% and 80.5%, respectively) and decreased NH3 emissions (by 23.5% and 18.9%, respectively).
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Effects of phosphogypsum and superphosphate on compost …
It was reported by Hao et al. (2005) that phosphogypsum, the main by-product of phosphoric acid production, might be effective in reducing CH 4 emissions during cattle manure composting by increasing SO 4 2− content of the compost, and Luo et al. (2013) indicated that the addition of phosphogypsum at a rate of 10% of total …
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Radioactive Material From Fertilizer Production | US EPA
Subpart R: National Emission Standards for Radon Emissions from Phosphogypsum Stacks This webpage has information about 40 CFR Part 61, Subpart R, a rule that protects people and the environment from the radon given off by phosphogypsum stacks. The States. Some states have worked with the EPA to write …
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Phosphogypsum – An Industrial Byproduct with Value
As a result, domestically produced phosphogypsum is stored in "stacks" all over the country – massive containment ponds where phosphogypsum is indefinitely piled. The International Atomic Energy Agency ( IAEA ) estimates that each year, 40 million tons of the waste are added to stacks in the US, and about 90 million tons annually outside ...
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A review on the environmental impact of phosphogypsum …
The PG production in a country commonly correlates with its phosphoric acid production, and thus with its number of phosphate deposits. In 2012, around 250 million …
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Phosphogypsum: Properties and Potential Use in …
• Discuss the uses of phosphogypsum in agriculture as a fertilizer, amendment to degraded soils, and as an additive fertilizer industry. • Define the PG impacts on crop production, …
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Effective and innovative procedures to use phosphogypsum …
Phosphogypsum (PG) waste is a by-product generated from wet-process phosphoric acid (H3PO4) manufacturing during phosphate rock decomposition. Worldwide, the annual production of PG ranges between 100 and 300 million tons, with only a few quantities utilized in several application domains (about 15%), the unused PG is usually …
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Effects of phosphogypsum and superphosphate on …
The addition of phosphogypsum and superphosphate drastically reduced CH4 emissions (by 85.8% and 80.5%, respectively) and decreased NH3 emissions (by 23.5% and 18.9%, respectively).
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CO₂ emissions
We can compare each country's total contribution to global emissions by looking at cumulative CO 2. We can calculate cumulative emissions by adding up each country's annual CO 2 emissions over time. We did this calculation for each region and the largest CO 2 emitters over the period from 1751 through to 2017. 3
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RADInfo National Emission Standards for Hazardous Air Pollutants
Phosphogypsum may be removed from a phosphogypsum stack only as expressly provided in this Subpart. After a phosphogypsum stack has become an inactive stack, i.e., no further routine additions of phosphogypsum will be made, the owner or operator shall assure that the stack does not emit more than 20 picocuries per meter per …
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Properties of supersulphated phosphogysumslag cement …
Supersulphated phosphogysum-slag cement (SSC) is a newly developed non-burned cementitious material mainly composed of phosphogysum (PG) and ground granulated blast furnace slag (GGBFS), with small amount of steel slag (SS) and clinker (CL). SSC is a kind of environmentally-friendly cementitious material due to its energy …
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Preparation of gypsum with high purity and whiteness from …
Phosphogypsum (PG) is a solid waste product generated during wet-process phosphoric acid production. Various impurities considerably reduce the purity, …
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Realising the circular phosphorus economy delivers for …
Phosphogypsum has minimal recycling utility due to its contaminants including cadmium, uranium, and other radionuclides. The USA's phosphogypsum waste is held …
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Phosphogypsum: potential uses and problems – a …
PG, discharged into the sea, watercourses or in wilderness stocks, contains toxic elements harmful to ecosystems and human health, including heavy metals and radionuclides, and there is therefore a …
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What Is My IP Address
Find out what your public IPv4 and IPv6 address is revealing about you! My IP address information shows your IP location; city, region, country, ISP and location on a map. Many proxy servers, VPNs, and Tor exit nodes give themselves away.
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Phosphogypsum: potential uses and problems – a review
Abstract Phosphogypsum (PG: CaSO4·2H2O) 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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Subpart R: National Emission Standards for Radon Emissions …
The regulations require that phosphogypsum be managed in engineered stacks, which are designed to limit public exposure from emissions of radon and other radionuclides. Owners and operators must monitor and report radon emissions from inactive stacks and take measures to keep radon emissions within the regulatory limit …
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Effect of phosphogypsum and dicyandiamide as additives …
The addition of phosphogypsum affected the emissions of both NH 3 and CH 4 during composting. Lower NH 3 emissions and higher NH + 4 content were detected in the treatments with phosphogypsum additives than in the control. There was a significant decrease in CH 4 emissions with phosphogypsum addition rate at 5% and …
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Applying to EPA for Approval of Other Uses of …
Phosphogypsum Stacks." The rule limits radon emissions from phosphogypsum stacks and requires disposal of phosphogypsum in stacks or piles, with exceptions for agricultural and research uses and other uses on a case-by-case basis. Applying to EPA for Approval of Other Uses of Phosphogypsum: Submitting a Complete Petition 1.0 Introduction
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Effects of phosphogypsum, superphosphate, and dicyandiamide on …
The total GHG emissions from the all treatments ranged from 63.6 to 181.2 kg CO 2-eq t −1 on a dry matter basis. The total GHG emissions from PPG and SSP treatments were lower than those of the CK treatment, with reductions of 19.5% and 46.9% (related to CH 4 emissions). The combinations of PPG and DCD or SSP and DCD also …
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