Question

Which among the following is the most suitable particle size of solid waste?

(a) Order of few tens of millimeter

(b) Order of few tens of centimeter

(c) Order of few tens of micrometer

(d) Order of few tens of decimeter

The question was posed to me by my school principal while I was bunking the class.

Query is from Microbes in Bioleaching Process topic in section Bioleaching and Biomining for Recovery of Resources of Environmental Biotechnology

Answer 1

Right answer is (c) Order of few tens of micrometer

Explanation: Decrease in particle increases the surface area that increases the contact area between the leaching agents and solid particle. Consequently, small solid particles increase the rate of leaching and its yield. Therefore, various experiments prove that highest solubilization rates have been found to occur in particles of sizes of the order of few tens of microns (Rossi, 1990).