A solution to the problem of wastewater treatment at remote workplaces and population centers has been adopted by Anglo Coal at its new Lake Lindsay open cut mine in central Queensland’s Bowen Basin.
Built into a standard 20 foot shipping container, the easily transportable Fixed Activated Sludge Treatment (FAST) solution is designed to handle 20 m3 of sewage per day from the mine site.
The Lake Lindsay mine is too far away from the Anglo Coal’s other industrial areas to share their facilities, so requires its own equipment maintenance workshops and offices for employees.
The 24/7 operation has about 60-80 people working on site at any one time.
“The FAST sewage treatment plant is doing the job effectively and economically,” Thomas & Coffey Water Plant Technician Supervisor Peter Anderson said.
Treated effluent waste water from the plant is mixed with mine and runoff water and sprayed on the mine’s coal haul roads for dust suppression.
Anderson does weekly, fortnightly and monthly bacterial checks on the effluent.
Another FAST wastewater treatment system at Anglo Coal’s nearby German Creek mine has been running for about 20 years.
Supplied by CST Wastewater Solutions (formerly Contra-Shear Technology) and installed by A1 Noble, the Lake Lindsay installation represents the latest generation of Smith & Loveless FAST systems.
The Smith & Loveless FAST process is now bring used on mining and construction sites, petrochemical and chemical plants, pulp and paper producers, food and beverage manufacturers, wineries, meatworks, schools and universities, restaurants, shopping centers, caravan parks, and boat marinas.
The process is a simple, efficient biological system that offers safety and flexibility for the operator.
Unlike conventional suspended growth systems, bacteria grow rapidly on the media while the liquid that evenly circulates through the media is essentially clear, with low solids levels.
As the bacteria grow and increase in thickness, the film strength of the bacterial growth weakens and a sloughing of surface solids occurs.
The microbes’ anaerobic action results in continuing reduction in cell mass and a reduced biological sludge accumulation to be removed from the bottom of the clarifier.
This lessens the required area for tankage and associated equipment.
Typically, an extended aeration plant has a Mixed Liquor Suspended Solids level (MLSS) of 3000-4000 mg/L.
At this level the clarifier is being operated at close to the maximum solids flux (sludge accumulation).
With the FAST treatment system, on the other hand, the bacteria grow on the submerged media, and the mixed liquor circulating through the bacteria-laden media is essentially clear and free of suspended solids.
This reduces the MLSS flow to the clarifier to approximately 100-400 mg/L and greatly reduces the amount of solids flux, which means less stress on the clarifier.
The history of FAST goes back to the early 1970s, when the US Coast Guard had a problem with ships cruising in coastal waters and dumping wastewater overboard, causing excessive pollution.
FAST systems arrive at the job site as complete, factory-built units or as large components for field assembly.
FAST can also be retrofitted into existing aeration tankage to boost capacity or performance without expanding the plant.
CST Wastewater Solutions
02 9427 1279