ALROSA intends to modernize freezing system at Mir Mine

ALROSA intends to modernize the freezing station (surface stowing system) at the Mir Mine, as it follows from the company’s request for commercial offers to develop design and engineering documentation for the project, according to the PRIME news agency.
The starting price announced by ALROSA is RUB 8.154 million. The company will accept bids until August 15, 2014 and plans to consider them before September 15, 2014.
The winner of this tender will be required to prepare the documentation (after choosing a supplying contractor) to replace the existing chiller units for cooling the intermediate coolant using ammonia refrigerant with a freon automatic chiller plant to cool the fluid.
According to the information about the purchase, the feasibility analysis and design documentation must be prepared before February 20, 2015; industrial safety examination passed before April 10, 2015; and the engineering documentation delivered before April 26, 2015.
The freezing station is used to freeze rock around the mouth and pile footing of the skip and cage shafts both during sinking, as well as during mining operations. Its total cooling efficiency is 3,500 kW.
The kimberlite Mir Mine is a primary diamond field discovered in 1955. Until June 2001, mining operations there were open-cut. Starting from 2009, diamond ore at Mir is recovered from the underground mine. To build it and provide safe mining at underground horizons, the bottom of the mothballed open pit has been specially treated to prevent the ingress of aggressive brines. ALROSA intends to recover diamonds from this underground kimberlite mine for another 30 years.