Thailand : Electricity from sewage water

Total savings: 40.000 tonns of CO2 per year
Local environment: Replacement of fossil fuels
Further advantages: Improved water and air quality
Local employment: Jobs in plant construction and plant operation

Project status Thailand

High demand of energy in the starch production

The starch plant is located in Thailand's Kalasin province, a rural region in the country's North-East. Embedded in the forests at the foot of the Phu Pan hills, the region is typified by agriculture, with farmers growing rice, sugar cane and cassava.

Thailand is one of the world's most important starch exporters, with its production based on cassava, a plant that grows well in dry and low-nutrient soil conditions. Until recently, the country's many starch factories were struggling with their high demand of water for washing the cassava, with pungent odour emissions and high fossil fuel cost for drying the starch. Today, funded by carbon revenues and private investment, a one-in-all solution successfully tackles the above problems and at the same time saves greenhouse gas emission from entering the atmosphere.

Producing Energy from the own residues

Prior to this small scale project activity, the plant's wastewater was treated in cascading open anaerobic lagoons, with a retention time of more than one year. This resulted in heavy emissions of methane, one of the strongest greenhouse gases, from the organic content of the wastewater. Now, the project activity replaces the old treatment with a modern Upflow Anaerobic Sludge Blanket (UASB) reactor system. The captured biogas is used for energy production instead of being released to the atmosphere, and replaces fossil fuels in the starch drying process which saves even more greenhouse gases from heating up the climate. In the end, the recycled water can be re-used in the plant for cleaning the cassava, which saves many tons of freshwater per day.

Apart from the positive climate effects, the project also benefits the local community, since the strong odour nuisance has dropped.