Beneficiation, Analysis and Industrial Utilization of Kaolin from Ghana

Eight different Kaolin samples were studied. Each sample was given serial number for easy reference. The beneficiation methods used in the project included a preliminary treatment of each sample; this involved hand 1cking of coarse gangue such as root, pebbles and coarse mica. After this treatment, each sample was subjected to gravity separation. Other beneficiation methods used included screening of samples at 120 mesh size and froth flotation using a flotation cell. After beneficiation, sodium dithionite, ammonium oxalate and oxalic acid were tested as bleaching agents and sodium dithionite was found to be the most suitable. Qualitative and quantitative analyses were carried out on the samples. Besides, moisture content and ignition loss were determined for each sample. Concentrations of Al2O3, SiD2, TiO2, Fe2O3, Na2O, K2O, CaO and MgO in the samples were determined by calorimetric and flame photometric techniques. Finally, physical properties involving oil adsorption, specific gravity, texture, finess and colour were determined for each sample. After gravity separation, the weights of recovered samples range from 31.52 to 81.48g out of 100.0g of raw samples used. Weight of samples recovered after screening 30.0g of each sample range between 16.59 to 28.23g. For froth flotation, weight of samples recovered after using 50.0g of each sample range between 47.42 to 49.88g. Results for moisture contest of samples range between 0.24 to 1.76% while ignition loss range between 7.79 to 31.67%. This thesis is divided into five chapters. Chapter or is a general introduction which deals with the origin of Kaolin and bow the deposits are formed. The uses of the clay have also been outlined aention4n the products which are made up of or contain Kaolin in diverse forms. The prominent deposits of the clay in Ghana have been mentioned here. In addition, the present status of kaolin utilization Ghanaian industries has been considered using GIHOC paints Company, Tema as a case study. Chapter two is on literature survey. In this chapter there has been a careful review of the way Kaolin deposits are formed. The chapter also contains to a great detail how different kaolin minerals are identified. Kaolin as a mineral possesses both physical and chemical properties. This chapter contains facts about these properties and their effects on the use to which kaolin can be put. Mining and beneficiation methods were also considered here with brief outlines on specific methods employed by some Companies in mining and beneficiating of kaolin. Finally a detailed outline on the technologies of some of the industrial utilizations of kaolin has been mentioned her. Chapter three has been devoted to experimental methods and their theories. This chapter has been divided into two broad sections. The first section is devoted to the chemistry of the analytical methods and the principles of the various instruments used in the experimental procedures. The second section is on the experimental procedures adopted in the study. Chapter four is on the results of the experiments performed. Chapter five has been devoted to discussion of results. Under it, the various methods of beneficiation used in the project have been discussed. A proposed pilot scale production scheme based on these methods of beneficiation has been put forward. The chapter also contains discussion of the results obtained from the analyses of the beneficiated products. Results were compared with those of well-known Commercial Kaolin samples and found to be in close conformity. Where deV1atioma were too much, possible reasons were put forward to explain the situation. The properties the kaolin samples were also compared with those of standard samples and aged upon these, the various Industrial uses for which the individual kaolin samples could be suitable were discussed in the chapter. The final thing considered in the chapter has been a survey work on the trend of worldwide and Ghana demand of kaolin. Despite the fact that me adequate data were available for a more comprehensive analysis on the economics of the present and future demands of kaolin in Ghana, an attempt has been made in this chapter to however give a rough idea about the present and future prospects of kaolin production in Ghanaian industrial scale.

Source: KNUST