More efficient system expected to save money.

Microscopic organisms that process waste at the Pratt waste water treatment plant will soon improve their efficiency when the digester at the plant switches from anaerobic (non-oxygen) to an aerobic (oxygen) system.

The belt press or digester uses biological organisms (microscopic bugs that eat waste) to process the waste and clean it up like the digestive system in the body, said Pratt City Manager Dave Howard.

The more oxygen in the system the more efficiently the microscopic organisms can produce the sludge.

The city was having difficulty getting rid of the sludge created in the current system

The usual method of disposal was to haul the product to area fields where it was land applied. However, disposal was a major problem for the city, Howard said.

"A lot of time we can't get out to the fields because of the weather," Howard said. "It was very inefficient."

Once the sludge has been processed, the treatment plant analyzes it and the state has to approve it before it can be applied to the soil and that takes time time.

Once the aerobic system is in place it will improve digestive efficiency and eliminate the sludge.

Upgrading the facility had become a vital issue. The amount of sludge had pushed the plant to critical levels and they were close to violating their discharge permit.

"We don't want to do that," Howard said.

During the wastewater treatment plant evaluation, it was determined that not only was an oxygen system needed but other changes needed to be made as well.

One of the changes was new covers for the equalization basins to prevent algae growth. Algae uses oxygen necessary to treat wastewater. By keeping the amount of algae down it improves system efficiency by helping keep the biological process alive.

Other improvements include a new maintenance building to replace to old building that will be used to house the new belt press that will increase oxygen in the system.

The system will also require an induced oxygen system pump to put pure oxygen into the waste system for more effective waste treatment.

The upgrades will provide a more efficient system that will help the city meet the wastewater treatment needs for years to come. It should also make the facility more economically efficient.

"We anticipate a substantial energy cost savings in plant operations," Howard said.

No specific date for project bids is set but they bids should go out in the near future. If those bids come back and are financially feasible, the project will probably start in spring 2013.

The city has been budgeting for some kind of improvement at the wastewater plant for six years. Because of the budgeting, the city should be able to do the project without a rate increase.