Future Carbon Fund by Asian Development Bank;

Author:Asian Development Bank;
Language: eng
Format: epub
Publisher: Asian Development Bank Institute
Published: 2017-08-15T00:00:00+00:00

Kinoya Sewerage Treatment Plant Greenhouse Gas Emission Reduction Project, Fiji.

Photo credit: Future Carbon Fund.

5

Case Studies

Double A Ethanol Wastewater Treatment Plant, Thailand

Enhancing the Community’s Quality of Life

Sitting in the courtyard of his home in Prachinburi Province in Thailand, 72-year old village leader and retired cassava farmer Puek Lebpayak describes how people from his village would relocate to urban areas in search of better jobs. Until a few years ago, agriculture was the main source of income for local residents. Now, nearly 200 meters (m) away from the village lies an industrial park that houses the E85 ethanol plant and its Wastewater Treatment Plant, formerly the Double A Ethanol Wastewater Treatment Plant. The project is located in Srimaphote, Prachinburi Province, 190 km east of Bangkok. “Life has improved for my people” Puek recounts. “There are many industries here. The project helped provide an additional opportunity for my people to work near their home town instead of moving away for work.” Although the project does not require huge manpower, it presents an opportunity for the locals to diversify their skills and gain new experiences. Ten employees, representing a third of the project’s staff, come from the local community.

The ethanol plant can produce 500,000 liters (l) of ethanol per day from cassava, a tropical crop cultivated extensively for its tuberous starch. The production of ethanol results in an average wastewater flow of 5,000 to 6,000 cubic meters per day. The large volume of wastewater is warm, concentrated, biodegradable, and nontoxic, with a chemical oxygen demand (COD) of approximately 50,000 milligrams per liter. It is therefore highly suitable for high-rate anaerobic treatment in the internal circulation anaerobic digesters installed at the project site. This is the first project in Thailand to use an advanced technology internal circulation reactor. The digesters convert the COD to biogas, yielding approximately 79,340 normal cubic meters of biogas per day. This is exported via pipeline and combusted in a limekiln boiler to generate heat close to the project site.25 The digested slurry produced by the internal circulation reactor is used as a fertilizer.

In the absence of the project, open anaerobic lagoons would have been used to treat the wastewater from the ethanol production. In Thailand, inexpensive, conventional open anaerobic lagoons are a common approach to treating wastewater from industrial plants. These result in high methane emissions. Methane is a potent GHG, with a global warming potential of 21 times that of carbon dioxide (CO2).26

Developed by the E85 Company Limited (E85), a daughter company of the National Power Supply Public Company Limited,27 the project was envisioned to avoid emitting 170,983 tCO2e per annum through the reduction of methane emissions from the wastewater treatment plant. The project results in additional GHG emission reductions by using biogas to avoid 19,758 tons of bunker oil in the boiler every year, although this is not claimed under the CDM project to ensure conservatism.

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.