Minetek aids US coal producer with dewatering & reclamation challenge
Located within the Illinois Coal Basin this mine has both surface and underground operations. The mine has been in operation since 1982 as a surface mine, before exploring deposits below ground in 2006.
Location – Williamsville, Illinois, United States
Type – Coal
Industry – Miniere
Application – Coal Slurry Impoundment
Product – Water Evaporation System Package
Volume throughput m3 + GPM – 90 m3/hour (400 GPM)
The Brief
In 2020 our client increased its ownership of the Illionois base coal in, in turn assuming long-term mine closure liabilities including the dewatering of their tailings storage facility. The site’s storage facility was at capacity reaching the end of its useful life after 39 years. The current tailings dam has a pool surface area of 85 acres with slurry pool volume sitting at approximately 11,600 square feet. Our client contacted Minetek to assist with the dewatering and reclamation of this storage facility. The entire 270-acre storage facility requires dewatering before reclamation can begin, with around 140 million gallons of water to be removed. The goal for our client is to be a zero-discharge facility ensuring environmental compliance.
Business Challenge
The quality of the Illinois basin water posed a challenge forthe mine due to high pH levels, chlorides, and sulphates. The pH level ranged between 8.0 to 9.0, with 2000 to 2200 mg/l of chlorides and 3200 3500 mg/l of sulphates. The permitted pond water quality discharge limits are 500 mg/l of chlorides and 2000 mg/l of sulphates.The mine had the option to discharge “free water” in excess of 140 million gallons. Due to the exorbitant costs of water treatment / reverse osmosis, Minetek’s water evaporators were a cost-effective & efficient long-term solution.
Choosing Minetek
Our client purchased 2 x Minetek Land-Based Water Evaporators to assist with the dewatering of their tailings dam. In addition to the Evaporators, Minetek supplied a high-volume head pump to supply water at high pressure. Minetek’s Land-Based Evaporators process 400 GPM (gallons per minute) of wastewater at 145 PSI (pound per square inch). Overall our client was able to achieve an evaporation rate upwards of 30%. Evaporating 120 GPM and 172,800 GPD (gallons per day) at an estimated 80% run time.
Risultati
Minetek were able to successfully work with the mine to scope, design and manufacture an evaporation solution with a total system capacity to process 400 GPM of wastewater at 145 PSI. This system was designed in alignment with our client's goal to significantly reduce the volume of the TSF, evaporating 120 GPM and 172,800 GPD (gallons per day) at an estimated 80% run time and evaporation efficiency rate of 30%. With Minetek's water evaporators, the mine was able to reduce water levels of the TSF by more than 2ft over a 4-month period. The total wastewater reduction is approximately 38 million gallons, with 20 million gallons attributed to Minetek’s water evaporators.