Hindustan Zinc is in the process of expanding its mining operation in order to ramp up output and it is the fourth major expansion plan of the firm.

The country's only integrated zinc producer is expanding operation at its Zawar and Dariba mines in a phased manner. It is also slated to develop two greenfield mines as part of its expansion plan.

The current expansion plan is attributed to the expansion at Rampura Agucha, the world's largest zinc producing mine, and Sindesar Khurd, a silver-rich mine.

Meanwhile, the firm plans to begin commercial production at Kayar in Rajasthan with initial capacity of 0.35 mn tpa in 2013-14. Further, it will develop a small mine at Bamnia Kalan in Rajasthan.

With these expansion plans, the firm aims to raise production from its mines by 20 percent to 1.2 million tonne (mn t) over the next three years.

The expansion plans may enable the firm raise its share in global mine production to 8 percent from current level of 5.5 percent.

The expansion plans come at a time when some of the world's largest zinc mines in Canada and Australia are being shut down resulting in shortage of the mineral in the global market.

Nearly 1.2 mn t of mine production, roughly about 10 percent of current global mine production, will be exhausted by 2016.