China
Africa
Explore chapters and articles related to this topic
Market Potential Assessment of Gypsum Industry
Published in Manjit Singh, Gypsum & Gypsum Products, 2023
We know phosphogypsum is a by-product of the phosphate fertilizer industry and emanates from the production of phosphoric acid from rock phosphate. Production of phosphogypsum in India is estimated to be 6.0 million annually16. The composition of phosphogypsum varies depending upon the source of rock phosphate and the process for manufacturing phosphoric acid17. The approximate composition of phosphogypsum is shown in Table 10.15.
Foamed concrete using waste materials: A review
Published in Sheela Evangeline, M.R. Rajkumar, Saritha G. Parambath, Recent Advances in Materials, Mechanics and Management, 2019
Sajan K. Jose, Mini Soman, Sheela Evangeline
Investigations on foamed concrete with phosphogypsum (PG) as an ingredient has been reported by Tian et al. PG is a waste of phosphoric acid manufacture by dehydrating process. It is a fine powder with high calcium sulphate content, which also contains few amount of impurities like phosphates, fluorides and organic matter [33, 34]. About five tons of PG are generated per ton of phosphoric acid production. With the rapid development of the phosphate fertilizer industry, global emissions in phosphogypsum are more than 150 million tons every year. When the large amount of phosphogypsum is dumped on land, it may result in the rapid change in pH, which can affect most species of fish, aquatic life and vegetation 35]. PG foam concrete mixtures are produced by using PG, cement, Ground Granulated Blast-Furnace Slag (GGBFS) or Fly Ash (FA), quick lime, sulphoaluminate, cement, water and foaming agent [36, 37]. As phosphogypsum is one without cementitious material, the compressive strength of the mix is highly correlated with PG dosage. When the percentage of raw phosphogypsum, increased from 40% to 70%, compressive strength value of foam concrete almost linearly decreased from 2.71 MPa to 1.14 MPa. The density increases slowly and later goes down with PG content increasing, which comes up to the peak when 55% PG is added.
Geomechanical provision of phosphogypsum stockpiling in high stacks
Published in Vladimir Litvinenko, EUROCK2018: Geomechanics and Geodynamics of Rock Masses, 2018
Yu.I. Kutepov, N.A. Kutepova, B.V. Levin, V.E. Mironov
In Russia the phosphogypsum has the status of industrial product, is included in “Fertilizers Phosphoric (Phosphatic)” section for No. 21 8293 0 of the All-Russian Product Classifier (ARPC). In accordance with GOST 125–79 “Binding gypseous substances. Technical specifications.” section it is allowed to use phosphogypsum for production of binding gypsums substances as well as rock gypsum. The Federal Road Transport Agency agreed on a company industry standard 24406528-01-2016 “Recommendations for road surface dressing made from phosphogypsum in roadways construction.” The Standard allows to use fresh phospho semi-hydrate in building a new solid foundation for road surface dressings with a high modulus of deformation. Besides, in some WPP producing countries phosphogypsum is used not only as a fertilizer but also as an ameliorants for alkaline soils, in road construction as a material for solid road foundations, in construction materials production such as cement, binding gypsum substances, gypsum rock etc.
Study on axial compression performance of original bamboo-fiber reinforced phosphogypsum composite walls
Published in Mechanics of Advanced Materials and Structures, 2023
Qishi Zhou, Wei Li, Jiefu Tian, Pengcheng Liu, Ning Jiang, Feiyang Fu
Due to the continuous development of global economy and society and the increasing demand for energy, the annual production of phosphate rock is gradually increasing, and a large amount of phosphogypsum waste is produced in the phosphate production process [33]. If phosphogypsum is not treated, it will lead to environmental pollution, destruction of land and vegetation, and even a threat to human health. Therefore, realizing the resource utilization of phosphogypsum is of great significance to the development of society. Phosphogypsum has advantages such as light weight and has been used in the construction industry [34, 35]. The author’s research group proposed a new type of original bamboo-fiber reinforced phosphogypsum composite wall. The original bamboo in the wall is wrapped by phosphogypsum, which has the advantages of light weight and green environmental protection. At the same time, phosphogypsum can protect bamboo from mildew, corrosion and moth. In order to study the axial compression performance of original bamboo-phosphogypsum composite wall, this article carried out eight wall tests and carried out finite element analysis, explored the influence of different parameters on the axial compression performance of composite walls, and proposed the calculation method of axial compression capacity and stiffness of the composite wall.
Laboratory investigation of cemented silt improved with bentonite and phosphogypsum in DCM walls
Published in European Journal of Environmental and Civil Engineering, 2022
Jianwen Ding, Xing Wan, Hanrui Zhao, Chen Guo, Ning Jiao
Furthermore, phosphogypsum is known as the main by-product during the manufacture process of phosphoric acid. It is reported that the phosphogypsum generated annually ranges from 130 to 180 million tons worldwide, but only an extremely low proportion of it (4.3% to 4.6%) is recycled (Tayibi at al.). Disposal of phosphogypsum not only occupies land sources, but also does threat to environment due to contained hazardous trace elements. This by-product gradually turns out to be a feasible construction and building materials. It is documented that phosphogypsum can be used to improve mechanical behaviour of subgrades (Degirmenci et al., 2007; Ding et al., 2019). However, the formation of ettringite is accompanied with remarkable swelling potential, which would destroy intrinsic fabric and cementation when excessive phosphogypsum is blended (Ding et al., 2017; Pollard et al., 1991; Puppala et al., 2005) . Thus, the amount of phosphogypsum should be determined carefully when it is used in roadway engineering.
Fluidized bed dryers in terms of minimizing environmental impact and achieving the sustainable development goals
Published in Drying Technology, 2022
Iryna Ablieieva, Nadiia Artyukhova, Jan Krmela, Myroslav Malovanyy, Dmytrii Berezhnyi
The digestate obtained after organic matter fermentation in the bioreactor is sent for separation and dewatering to the separator. Upon completion of this process, liquid and solid digestate fractions are obtained. The liquid fraction can be used immediately as liquid fertilizer, and the solid fraction is sent to a disk granulator, where mineral fertilizer and phosphogypsum are also added. In order to obtain organo-mineral granular fertilizer, it is proposed to use mineral fertilizer for the core, and the shell is formed from the solid phase of the digestate together with phosphogypsum binder. Phosphogypsum is a by-product of the chemical industry, formed during the sulfuric acid processing of apatites or phosphorites into phosphoric acid (extraction) or concentrated phosphorus fertilizers. Such application of the phosphogypsum is seen as a promising direction of waste management in line with the principles of balanced environmental management.