Overview of Current Phosphoric Acid Production Processes and a New Idea of Kiln Method

2020 ◽  
Vol 17 ◽  
Author(s):  
Guangya Zheng ◽  
Jupei Xia ◽  
Zhengjie Chen
Keyword(s):  
Phosphoric Acid ◽  
Acid Production ◽  
Phosphate Rock ◽  
Low Grade ◽  
Production Methods ◽  
Production Processes ◽  
Major Equipment ◽  
Development Prospects ◽  
Great Competitiveness

: China primarily contains medium and low-grade phosphorus ores that are used to produce phosphoric acid. Here, we provide an overview of phosphoric acid production processes, including wet, thermal, and kiln methods, as well as the fundamental principles, major equipment, and technological aspects of each process. Progress in the kiln method using lowgrade phosphate rock is described, which involves the KPA and CDK processes. The literature shows that the addition of admixtures adds great competitiveness to kiln phosphate production methods and has considerable development prospects.

Distribution of natural radionuclides during the processing of phosphate rock from Itataia-Brazil for production of phosphoric acid and uranium concentrate

2000 ◽  
Vol 88 (9-11) ◽  
Author(s):  
H.T. Fukuma ◽  
E.A.N. Fernandes ◽  
A.L. Quinelato
Keyword(s):  
Solvent Extraction ◽  
Phosphoric Acid ◽  
Half Life ◽  
Pilot Plant ◽  
Acid Production ◽  
Phosphate Rock ◽  
Natural Radionuclides ◽  
Wet Process ◽  
Uranium Concentrate ◽  
Uranium Phosphate

A high-uranium phosphate rock from the Itataia deposit, located in the state of Ceará, Brazil, was milled in a pilot plant for wet-process phosphoric acid production. Further processing with solvent extraction (DEHPA/TOPO) was used aiming to recover uranium from the phosphoric acid. The distribution of natural radionuclides with long physical half-life of the

scholarly journals Studies on the transformation of calcium sulphate dihydrate to hemihydrate in the wet process phosphoric acid production

2012 ◽  
Vol 14 (2) ◽  
pp. 80-87 ◽  
Author(s):  
Barbara Grzmil ◽  
Bogumił Kic ◽  
Olga Żurek ◽  
Konrad Kubiak
Keyword(s):  
Phase Composition ◽  
Phosphoric Acid ◽  
Diffraction Analysis ◽  
Acid Production ◽  
Phosphate Rock ◽  
Calcium Sulphate ◽  
Industrial Plant ◽  
X Ray Diffraction ◽  
X Ray ◽  
Wet Process

Studies on the transformation of calcium sulphate dihydrate to hemihydrate in the wet process phosphoric acid production The influence of the process temperature from 85°C to 95°C, the content of phosphates and sulphates in the wet process phosphoric acid (about 22-36 wt% P2O5 and about 2-9 wt% SO42-) and the addition of αCaSO4·0.5H2O crystallization nuclei (from 10% to 50% in relation to CaSO4·2H2O) on the transformation of calcium sulphate dihydrate to hemihydrate has been determined. The wet process phosphoric acid and phosphogypsum from the industrial plant was utilized. They were produced by reacting sulphuric acid with phosphate rock (Tunisia) in the DH-process. The X-ray diffraction analysis was used to determine the phase composition and fractions of various forms of calcium sulphates in the samples and the degree of conversion of CaSO4·2H2O to αCaSO4·0.5H2O and CaSO4. It was found that the transformation of CaSO4·2H2O to αCaSO4·0.5H2O should be carried out in the presence of αCaSO4·0.5H2O crystallization nuclei as an additive (in the amount of 20% in relation to CaSO4·2H2O), at temperatures 90±2°C, in the wet process phosphoric acid containing the sulphates and phosphates in the range of 4±1 wt% and 27±1 wt%, respectively.

Phosphoric acid production by attacking phosphate rock with recycled hexafluosilicic acid

2017 ◽  
Vol 161 ◽  
pp. 21-27 ◽  
Author(s):  
S. Matta ◽  
K. Stephan ◽  
J. Stephan ◽  
R. Lteif ◽  
C. Goutaudier ◽  
...  
Keyword(s):  
Phosphoric Acid ◽  
Acid Production ◽  
Phosphate Rock

scholarly journals The Use of Heat From the Incineration of Municipal Solid Waste for Processing of Phosphogypsum

2018 ◽  
Vol 7 (4.3) ◽  
pp. 344 ◽  
Author(s):  
Olga Krot ◽  
Varvara Vinnichenko ◽  
. .
Keyword(s):  
Phosphoric Acid ◽  
Building Material ◽  
Acid Production ◽  
Industrial Waste ◽  
Phosphate Rock ◽  
Operating Temperature ◽  
Experimental Studies ◽  
Efficient Utilization ◽  
High Quality ◽  
Global Issues

Municipal landfills and open dumps with industrial waste are global issues which impact on the environment and on the health of populations. The production of phosphoric acid from natural phosphate rock gives rise to an industrial by-product called phosphogypsum, containing mainly dihydrated gypsum. Five tons of phosphogypsum are generated per ton of phosphoric acid production. The technology of roasting of phosphogypsum in a dehydrator, which is a mine, has been described in the article. Such reprocessing of the waste makes it possible to obtain a ready-made high-quality building material. The development of a complex that processes wet and highly adhesive phosphogypsum using the heat of combustion of alternative fuel (municipal waste) is consistent with the synergetic concept of environmentally efficient utilization. Experimental studies identify the most rational parameters of the dehydrator, namely, its operating temperature, have been conducted. The temperature of a heat carrier (air) varied from175 °Cto350 °Cin the experiment.  

scholarly journals Feasibility of fly ash as fluxing agent in mid- and low-grade phosphate rock carbothermal reduction and its reaction kinetics

2021 ◽  
Vol 10 (1) ◽  
pp. 157-168
Author(s):  
Biwei Luo ◽  
Pengfei Li ◽  
Yan Li ◽  
Jun Ji ◽  
Dongsheng He ◽  
...  
Keyword(s):  
Particle Size ◽  
Fly Ash ◽  
Reaction Time ◽  
Carbothermal Reduction ◽  
Industrial Waste ◽  
Phosphate Rock ◽  
Molar Ratio ◽  
Low Grade ◽  
Carbon Excess ◽  
Fluxing Agent

Abstract The feasibility of industrial waste fly ash as an alternative fluxing agent for silica in carbothermal reduction of medium-low-grade phosphate ore was studied in this paper. With a series of single-factor experiments, the reduction rate of phosphate rock under different reaction temperature, reaction time, particle size, carbon excess coefficient, and silicon–calcium molar ratio was investigated with silica and fly ash as fluxing agents. Higher reduction rates were obtained with fly ash fluxing instead of silica. The optimal conditions were derived as: reaction temperature 1,300°C, reaction time 75 min, particle size 48–75 µm, carbon excess coefficient 1.2, and silicon–calcium molar ratio 1.2. The optimized process condition was verified with other two different phosphate rocks and it was proved universally. The apparent kinetics analyses demonstrated that the activation energy of fly ash fluxing is reduced by 31.57 kJ/mol as compared with that of silica. The mechanism of better fluxing effect by fly ash may be ascribed to the fact that the products formed within fly ash increase the amount of liquid phase in the reaction system and promote reduction reaction. Preliminary feasibility about the recycling of industrial waste fly ash in thermal phosphoric acid industry was elucidated in the paper.

Dermal fibrosarcoma in a Cashmere goat

2019 ◽  
Vol 47 (03) ◽  
pp. 192-195
Author(s):  
Julia Schoiswohl ◽  
Bianca Lambacher ◽  
Andrea Klang ◽  
Reinhild Krametter-Frötscher
Keyword(s):  
Differential Diagnosis ◽  
Case Report ◽  
Connective Tissue ◽  
Malignant Tumors ◽  
Histopathological Examination ◽  
Low Grade ◽  
Cashmere Goat ◽  
Short Lifespan ◽  
Production Processes

AbstractFibrosarcomas are malignant tumors of the connective tissue, which are characterized by proliferation of fibroblasts. Most of these tumors are localized subcutaneously and cause different symptoms depending on their location. The case report describes a dermal tumor on the outside of the pinna in a 7-year-old female Cashmere goat. The tumor was surgically removed and histopathological examination revealed a low grade fibrosarcoma. Although tumors are rare in ruminants because of the animals’ short lifespan (age of slaughtering in most cases < 24 months) in modern production processes, they should be considered as a differential diagnosis.

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