In the age of advanced technological development, man can’t but get abreast with modern trend in mining especially in the quantity of materials used in production and construction. Glass production emanated from its crucial need to enhance human basic and technical needs which rested in the ace of development.
Glass is however an inorganic product of fusion which has cooled to a rigid shape without crystallization. The major raw materials of glass fusion (soda ash, limestone and silica) introduced in proportions derived its most important constituent silica from sand.
Despite the abundant of silica in the earth crust, commercial deposits are relatively scarce.
The process of dredging evolved from the use of simple implements such as shovels and in some areas divers go down the river bed with buckets to bring the material sort out.
As technology is advancing man moved from the use of these simple crude implements to the use of more sophisticated machines, such as the bucket wheel excavators and subsequently the use of dredgers. There is the diesel powered and electrically powered types. As the process of evolution of mining sand is traced backward, yield of optimal quantity of sand is achieved through dredging.
The low quantity of sand mined by other method of sand mining is as a result of limited access to the sand deposit. Innovations have been forced by technological advances or new geological finds.
The usual comment when asked about what is new in raw materials, is that nothing has changed over 30 years. Infact remarkable improvements have been achieved in mining and beneficiation of sand.
Minor raw materials in glass production
There are most introduced in trace amount depending on the property expected of the glass product. Minor in production of the batch, but often critical effect on processing, yield and marketability of glass product.
Examples of materials are:
1) Colourant / Decolorants – Chromite for armber colour
– Selenium for flint green
– Charcocal for green glass
2) Refining Agents – Sodium Sulphate
3) Redox Agents – Coal or Charcoal
Raw material specification
There are two basic specifications, viz;
1) Chemical Specification
2) Physical Specification
Chemical specification
The naturally occurring materials contain some impurities. Hence, there should be a maximum specification for these impurities. Also the maximum specification for the oxide for which the raw material is used should always be specified.
