Method for reducing fluoride in diluted phosphoric acid by wet process

A wet-process phosphoric acid and phosphoric acid technology, applied in chemical instruments and methods, phosphorus compounds, inorganic chemistry, etc., can solve the problems of sodium sulfate reducing fluorine content technology, no patented technology, etc., achieve low fluorine content, simple use, and low energy consumption low effect

Inactive Publication Date: 2009-09-09
WENGFU (GRP) CO LTD
View PDF3 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

So far, there have been no reports on the use of sodium sulfate to reduce fluorine content in dilute acid, and there is no related patented technology

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0010] Embodiment 1 In the phosphoric acid plant of Wengfu Phosphate Fertilizer Plant of Wengfu (Group) Company, Na is added as required 2 SO 4 120% of the calculated amount of sodium sulfate was added to the digester and the reaction time was maintained for 1 hour. After testing, the fluorine content in the prepared dilute phosphoric acid decreased from 2.5% to 1.8%, and the fluorine content in the dilute phosphoric acid decreased by more than 50% year-on-year.

Embodiment 2

[0011] Embodiment 2 In the phosphoric acid plant of Wengfu Phosphate Fertilizer Plant of Wengfu (Group) Company, add Na as required 2 SO 4 100% of the calculated amount of sodium sulfate was added to the digester and the reaction time was maintained at 1.5 hours. After testing, the fluorine content in the prepared dilute phosphoric acid dropped from 2.5% to 1.2%, and the fluorine content in the dilute phosphoric acid decreased by more than 52% year-on-year.

[0012] The dilute phosphoric acid after defluorination by the above-mentioned embodiment is concentrated, and the fluorine content in the obtained concentrated phosphoric acid is reduced from 1.1% before dilute acid defluorination to 0.4%. The reduction of fluorine content in wet-process phosphoric acid reduces the corrosion of fluorine on the equipment and pipes of the phosphoric acid plant, and improves the operating rate of the plant.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

A method for reducing fluoride in diluted phosphoric acid by wet process is provided. In the method, sodium sulfate is taken as defluoridator, phosphoric acid is added during production of phosphoric acid by wet process for reaction to extract sections, reaction time between sodium sulfate defluoridator and hydrofluosilicic acid in slurry is maintained between 0.2-6 hours; fluorine in diluted acid is precipitated in the form of fluoride or fluorosilicate to enter phosphoric acid slurry solid phase; then, when being filtered, phosphogypsum enters phosphoric acid slurry solid phase to be separated and removed, thus lowering fluorine content in diluted phosphoric acid. Compared with the traditional defluorination method, the method of the invention has the following advantages: 1. defluorination efficiency is improved by more than 50%; 2. energy comsumption is low or process flow is short, production cost is lowered by more than 10% compared with the production cost of defluorinating phosphoric acid; 3. corrosion of fluorine on pipelines of the devices are reduced by about 5-15%, operating ratio of the devices is improved by about 1%; 4. the produced phosphate fertilizer products can meet the growth requirements of high-end crops; 5. the defluorination method is simple, convenient and easy to operate and control; 6. the investment is small. The method of the invention is applicable to factories producing phosphoric acid by wet process.

Description

technical field [0001] The present invention relates to phosphoric acid, and furthermore, to wet-process phosphoric acid, in particular, to a method for reducing the fluorine content of wet-process phosphoric acid dilute acid. Background technique [0002] As we all know, in the production of wet-process phosphoric acid, due to the large amount of fluorine contained in the raw material phosphate rock, fluosilicic acid is formed after the reaction. After fluosilicic acid enters the system, it will seriously corrode the equipment and pipelines of the system, affecting the normal operation of the device. The traditional method of removing fluorine is to wash with water to absorb the SiF collected from the concentration and evaporation during the concentration of phosphoric acid. 4 And HF, or add defluorinating agent to concentrated phosphoric acid. These methods have low defluorination efficiency, and the fluorine content in the product phosphoric acid is high. Using phospho...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C01B25/237
Inventor 王江平郭仕伟张涛刘海冯克敏文慧姚石林李维红吴松张天毅
Owner WENGFU (GRP) CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap