Year: 2020
Type: article
Abstract: reSeArch oN techNoloGy of coMPlex ProceSSING of PhoSPhoGyPSuMPurpose.To conduct systematic studies on the process of obtaining rare earth elements from phosphogypsum by sulfate acid treatment.To determine the concentration of acid and rare earth elements in the filtrate after phosphogypsum excretion in the samples, depending on the ratio of phosphogypsum : acid 1 : 1.5; 1 : 2 and 1 : 2.5.To test purified calcium sulfate as a reagent for the extraction of phosphates from urban liquid waste sludge, to extract organ-mineral fertilizer from purified phosphogypsum and activated sludge from wastewater treatment plants.Methodology.For research, a laboratory unit for complex processing of phosphogypsum was prepared and the principle of its work was described.The experimental studies were performed using trilon B titration techniques to determine the rare earth ele ment concentration and NaOH titration to determine the acid concentration.A photometric method was used to determine the concentration of inorganic phosphates in the wastewater.findings.The content of acid in the filtrate at different ratio of "phosphogypsum: acid" from the enterprise "Dnipro Mineral Fertilizer Plant" and from the waste heaps was revealed.It is established that the concentration of acid increases with the ratio of "phosphogypsum: acid" from 1 : 1.5 to 1 : 2.5, respectively.The obtained organicmineral fertilizer corresponds to DSTU 7369:2013.originality.The regularities of the process of acid treatment of phosphogypsum depending on the origin have been established, and it is found that the concentration of the rare earth elements and acid is higher in phosphogypsum, which is obtained at the Dnipro Plant of Mineral Fertilizers than in phosphogypsum selected from waste heaps.The dependence of the ratio "phospho gypsum: acid", namely 1 : 1.5; 1 : 2 and 1 : 2.5 on the concentration of acid and rare earth elements in the samples was found.It was established that the presence of activated sludge in anoxic mode for 30 h leads to an increase in the content of phosphates in the aqueous phase by 2.6-2.8times.Dependences of the process of extraction of phosphates from urban liquid waste sludge by phosphogypsum were obtained.Organicmineral fertilizer from activated sludge of urban wastewater treatment plants and purified phosphogypsum was obtained, which meets the requirements of DSTU 7369:2013. Practical value.A laboratory unit has been developed for obtaining purified phosphogypsum from soluble impurities.It is pro posed to use purified phosphogypsum as a raw material in agriculture for the organicmineral fertilizers and composts production, a reagent for the extraction of phosphates from wastewater and in the building materials industry to obtain gypsum binders.The studies made it possible to quantify the concentration of rare earth elements and acids in phosphogypsum, as well as their possible selection as valuable products from the filtrate.
Authors: O.V Nazarenko, A.V Ivanchenko
Institution: Dniprovsk State Technical University
Language: English
Subfield: Building and Construction
Field: Engineering
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W3095696248