Department of Industrial Design Faculty of Environmental Technology – IT Assignment Help

Assignment Task

Task    

Background-  of the Study The role of bentonite clay in economic development of any nation cannot be underestimated in consideration of its use in oil drilling mud formulation, fillers for papers, binder to foundry sand, pharmaceutical products, adsorbents, and catalyst in the chemical process industries. It is a light colour clay that expand in water which is composed predominantly of the clay minerals montmorillonites, a sub-group within the smectites group, derived from deposits of weathered volcanic ash with a chemical formula m(Mg[Si4O10]x[OH]2) XP([Al,Fe]2x[Si4O10]) m:p = 0.8 – 0.9. However, depending on the nature of their genesis a variety of accessory minerals occur along with the montmorillonites (Aliyu, Garba, Danshehu, Argungu, & Isah, 2014). These may include quartz, feldspar, calcite, gypsum, dolomite, biotite, crystobalite, plagioclase, and ferruginous compounds (Ahmed et al., 2012). Bentonite were categorized in to natural sodium bentonite or sodium montmorillonite, natural calcium bentonite or calcium montmorillonite and sodium activated bentonite or sodium activated montmorillonite (Salahudeen et al., 2012) There are also the potassium, magnesium, and lithium types. Natural sodium bentonite as the name suggests occurs with sodium as the predominant exchange cation. It is characterized by high swelling, high liquid limit, and high thermal durability, and finds application as a binder to synthetic sand for foundry work. The majority of bentonite occurring worldwide are of the calcium type. Calcium bentonite has lower swelling and liquid-limit values compared to natural sodium bentonite. It is used as a bleaching agent in cooking oil industries, and lubricant oil recycling, as a catalyst, absorber, and filler, among others. The calcium bentonite can be transformed to sodium bentonite through modification degree (cation exchange of the clay, polar additives, and dispersion of the clay in an organic liquid). Also to be called organo-clay (Hill; Jain, 2003). Apart from petroleum, gas, and coal resources, the exploration, mining, and exploitation of Nigeria’s mineral resources have not received sufficient attention.

Delving into the geological survey of Nigeria soil (Aliyu et al., 2014; Eunice et al., 2013). Bentonite tuffs have been reported to occur in the Benue trough and around the Jos Plateau, but none of these was known to be associated with appreciable bentonite formation. Bentonitic clays also exist in the Northeast quadrant of Nigeria (Borno, Yobe, Taraba, Gombe, Bauchi and the Adamawa States) where a probable reserve of more than 700 million tons has been indicated. The most of these are members of the Pindiga Formation in Upper Benue trough in north-eastern Nigeria to be Ca-based (Khalaf & Al-Galbi, 2019). Similarly, over 90 million tons have been reportedly found in Afuze, Ekpoma-Igueben road, Ovibiokhuan, and Okpebho areas of Edo State. Some occurrences have also been reported in Abia, Ebonyi, and Anambra States(Aliyu et al., 2014). The present level of consumption of bentonite in Nigeria as of 2020 was reported to be about 500,000 metric tons, much of this was met by importation (Igwilo et al., 2020). Casting is the formation of a solid body of predetermined size and shapes from a melt by a process of solidification in a mould. Foundry technology is the art and science of the processes and materials used in manufacturing castings from metals and alloys. It deals with the manufacture of moulds & pattern, melting practices, metal treatment, pouring methods and processes for finishing castings, and the equipment used. Moulding practice deals with the production of moulds, which are Permanent moulds and Temporary moulds. Permanent moulds are reusable, and are usually made of metal, more rarely of graphite or refractory ceramic. These moulds are mainly used for non-ferrous metals, an important advantage of these moulds are the high rates of cooling and the clean casting surfaces. Temporary moulds consist of the basic materials, a binder system, and some additives. The basic materials are granular substances of washed, classified, and dried different silica sands. These basic materials (moulding sands) may be classified into natural moulding sand, high silica sand, special sand such as zircon, olivine, chamotte, chromite, chrome-magnesite, corundum, magnesite, sillimanite and mullite, and Bonding clays (bentonite) (Hill; Jain, 2003).