الفهرس 
NTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Phosphate rock is the major source of phosphorous, which consider an essential element for plant and animal nutrition. The marketable phosphate is usually 30% P2O5 or higher. The run-of-mine material is mostly of lower grade which needs processing or upgrading. Furthermore, during the last decade, there have been numerous published articles which indicate that phosphate deposits reserves are expected to be depleted in 50-100 years and peak phosphate production is expected to be reached in 2033-2034. The main target of this study is the beneficiation of low-grade phosphate rock in order to increase the P2O5 content up to industrially acceptable level to manufacture phosphoric acid by wet process for using with local available materials to produce dicalcium phosphate (DCP) as an important source’s for animal nutrition. The processing techniques of phosphate ores depend mostly on the type of associated gangue minerals present in the mined rock. In some cases, simple, inexpensive techniques are enough to produce the required grade. For example, crushing and screening is used to get rid of the coarse hard siliceous material, and attrition scrubbing and desliming is used to remove the clayey fine fraction. In this work, desliming and gravity separation technique has been adopted to upgrade the Egyptian phosphate ore from East Siba’eya area, Nile Valley, Egypt.
The present thesis is composed of a three main chapters, each of which can be summarized as follow:
THE FIRST CHAPTER
This chapter concern with a full literature survey of the subjects and the research published in this field and methods that used to upgrade low-grade phosphate ore.
The main points that have been discussed through this chapter can be summarized as follow:
❖ The geology and mineralogy of phosphate rocks.
❖ Distribution of phosphate rock in Egypt
❖ Beneficiation of phosphate rock, and several techniques for upgrading ores.
❖ History of Wilfley table as one of gravity separation techniques and identification in terms of origination place, time, types and characterization accurately.
❖ The production of phosphoric acid by thermal process.
❖ The production of phosphoric acid by wet process. Focusing on the production with sulphuric acid and its types.
❖ The impurities present in phosphoric acid.
❖ The effect of impurities in properties of phosphoric acid.
❖ Pre-treatment of phosphoric acid.
❖ Reviewing of the different techniques concerning the removal of organic matters and fluorine from wet process phosphoric acid.
❖ Principal types of animal feed phosphates (DCP).
THE SECOND CHAPTER
In this chapter, the utilized chemicals, reagents, materials, apparatus, instruments and equipments were stated. We can summarize the experiments which have been carried out in this work as follow:
❖ Preparing (crushing), analysis and classification of the low-grade phosphate sample whereas, the degree of crushing to generate a representative sample for mineral liberation and beneficiation purposes had to be considered.
❖ Using physical treatment technique as a pre-treatment to remove fine clay as much as possible from low-grade phosphate sample.
❖ Beneficiation of studied phosphate ore sample via shaking table
❖ Preparation of phosphoric acid from upgraded phosphate rock by wet process involving sulphuric acid.
❖ Study different factors affect the preparation of phosphoric acid.
❖ Removal of organic matters from phosphoric acid using local clay.
❖ Study the removal of fluorine from wet process phosphoric acid using white sand as a source of silica and sodium carbonate as a source of alkali metals.
❖ The parameters affecting the defluorination process of WPPA, such as temperature, reaction time, silicon to fluorine stoichiometric ratio, and alkali salt to fluorine stoichiometric ratio.
❖ Study the preparation of dicalcium phosphate from defluorinated phosphoric acid using calcium hydroxide, and quality considerations and product specifications.
THE THIRD CHAPTER
The results of experimental chapter were declared and discussed in this chapter. This chapter consists of three main parts; the first part is concerned with beneficiation of the low-grade ore sample involving Wilfley shaking table as a gravity separation applied technique. The second part including the factors which affect the preparation and purification of phosphoric acid. The final part including the preparation of dicalcium phosphate (DCP) of acceptable quality for animal nutrition as an application of the obtained crude phosphoric acid and proposed flow sheet for the preparation process of phosphoric acid and phosphogypsum from the low-grade studied sample.
The first part
This part includes classification, chemical analysis and preparation of the examined sample (5000+300gm for chemical analysis) for beneficiation using Wilfley shaking table as a suitable economic feasibility technique, with considering the variables affecting separation of phosphate ore minerals as, the size fractions less than 100 μm the slope of the deck was 10°, a feed water flow rate of 8 liters per minute and a dressing water flow rate of 10 liters per minute. Under these parameters, the examined low-grade phosphate ore from East Siba’eya area can be potentially upgraded. Prior to involving shaking table in ore upgrade, washing and desliming are introduced for 15 minute to remove fine clay from ore using sieve of 354 μm (-45) mesh (British standard). The screen products, over size (separation feed), were conducted in shaking table and under size (slimes) were calculated together with dried clay resulting from the washing process as percent on weight bases and analyzed for their P2O5 and other contents. The results show promise for the produced grades of (26.90%–33%) P2O5, and variant weights (25.40-