Efficient And Effective Municipal Wastewater Treatment With Science And Nature

Szarvas is a relatively modern town in Hungary, about 170 kilometres from Budapest. Populated by less than 20,000 people, Szarvas’ modern history dates back to the early 18th century when Slovak settlers moved into the region.

With the help of Lutheran priest Samuel Tessedik, the town was rebuilt, with schools being built and barren lands being reclaimed using modern agricultural techniques.

After the Second World War, the town’s authorities decided to make education the focus, leading to the creation of the Irrigation Research Institute and the Aquaculture Research Institute, which later merged into one body.

Along with these, Szarvas also boasts of a prominent teacher training institute and the Faculty of Agricultural Water and Environmental Management, making it an important academic centre in Hungary.

The town’s municipality contacted our partner in Hungary to help resolve issues at their municipal wastewater treatment plant.

There were several issues the plant was struggling with. They needed help with effluent quality improvement because of continuous discharge limit violations, especially with COD, BOD, NH4+, TN, and TP levels.

The plant also wanted a reduction in the excess sludge quantity. Lastly, they were looking at solutions that could increase the treatment capacity of the activated sludge.

This was an attempt at making the plant more energy-efficient by shutting down 3 of the 6 oxidation ditches in use at the plant.

After a thorough analysis of the plant and desired outcomes, our experts recommended treatment with Bioclean STP.

Bioclean STP is a proprietary blend of numerous specially selected naturally occurring microbial strains that degrade complex organic matter in sewage.

Bioclean STP minimises sludge volume and improves good floc formability, accelerating biomass settling.

Incompletely degraded sewage results in the emission of foul odours resulting from ammonia and hydrogen sulphide production.

Bioclean STP ensures complete degradation of organic matter, ensuring no production of hydrogen sulphide production & ammonia, thus preventing malodours.

The microbes in Bioclean STP suppress pathogens prevalent in sewage waters and reduce health risks. Bioclean STP also stabilises the STP & helps it withstand shock loads.

Bioclean STP is easy to apply and provides 100% efficiency, regardless of weather conditions. It improves STP resistance to shock loads, improving plant efficiency and STP stability.

We started with a shock dose of 11 kg of Bioclean STP per day to improve treatment efficiency at the Szarvas plant.

After a week of this, we reduced treatment to 1.5 kgs per day for 5 weeks, which is now the regular maintenance dosage at the plant.

As expected, Bioclean STP came through with glowing returns.

Sludge Reduction

The average quantity of waste activated sludge (WAS) before the biotechnological optimization was 120 m3/day.

During the optimization process this amount has been significantly decreased to 50 m3/day without a significant increase in the WAS MLSS concentration.

The plant does not have a primary clarifier and the degradation of particulate organic matter contributed to the decrease of the produced sludge’s quantity.

Energy Consumption

The plant operated with 6 oxidation ditches before the biotechnological optimization.

Treatment with Bioclean STP has ensured that 2 ditches can be fully shut down with a third one only operating partly, bringing down average power consumption by 12%.

Polyelectrolyte Consumption

The quantity of the polyelectrolyte used for dewatering the sludge has been reduced from 50 kg/month to 13 kg/month [effluent parameters].

The quality of the treated water has improved due to the enhanced removal of organic matter and the stable nitrification; the fluctuation of the parameters has become moderated.

The operation of the secondary clarifier has been stabilized due to the improvement of the floc structure, decreasing the suspended solids in the effluent.