Wastewater treatment combined with biogas production

St. Antonius Hospital in Ampenan had to solve a pressing problem: how to treat the 20 cubic metres of wastewater produced daily by 150 staff and patients? The existing catch pit was too small, and untreated wastewater sometimes even managed to enter the water supply and was used for washing or for drinking. The unhygienic water supply was responsible for spreading disease.

A new wastewater treatment plant was needed, and it had to satisfy a number of requirements. Firstly, it had to meet national standards. It also had to be suitable for operation by local staff. It had to function without an external energy supply and mechanical parts. And finally, it should not be troublesome in terms of odour, nor should it attract flies and mosquitoes.

The best option was found to be an anaerobic wastewater treatment system. And this offers an additional advantage: the wastewater fermentation process in biodigestors releases energy in the form of biogas. This can be collected and used for heating water and for cooking. The fermented, odourless and germ-free solid residue is a high-quality fertiliser; the treated wastewater can be used for irrigation.

With MISEREOR’s support, plants similar to the one in St. Antonius Hospital in Ampenan have been built for other Indonesian hospitals and for hospitals and boarding schools in Africa.