A United Nations Industrial Development Organization (UNIDO) technical assistance programme with the Senegalese government’s Office for Industrial Upgrading (Bureau de mise à niveau des Entreprises, BMN) has helped the country’s main slaughterhouse transform itself from a top polluter into a clean energy producer.

The Société de Gestion des Abattoirs du Sénégal (SOGAS) is a major player in the meat sector in the country, and its slaughterhouses ensure a daily supply of more than 20,000 tonnes of meat, most of which is consumed in the capital, Dakar.

The company’s Dakar slaughterhouse is located near the seafront at Hann Bay, and previously the method of disposing of wastewater (blood, fat, hair, faeces, urine, etc.) from the slaughterhouse was to discharge it into the sea. Hann Bay is a highly populated area and, in former times, fishing supported a thriving community and local residents bathed in the sea. However, beginning in the late 1960s, new industries developed along the seafront and an increasing discharge of industrial pollution rendered the bay exceedingly toxic. According to a recent report by Radio France International, the SOGAS slaughterhouse became one of  the top five polluters in the area.

To address the problem, the BMN, with technical assistance from UNIDO, has helped SOGAS implement an upgrading project that uses an innovative solution to convert its production waste into energy.

Together with Thecogas Senegal, a company that has been involved in producing clean energy for ten years, SOGAS now uses animal stomach contents as the raw material for producing gas and, from that gas, electricity. Every day, a truck makes the rounds to collect and transport the waste to a pit where the wastewater is separated from the solid solution. The solid solution is then sent to a 4000m3 bio-digester which constantly stirs the substrate, preventing it from becoming a thick paste. After 40 days or so, a fermentation process produces methane gas and the vast canvas that covers the bio-digester starts to inflate. Then the unprocessed gas is pumped along pipes to a refinery which removes water and reduces the amount of hydrogen sulphide. The purified gas is then burnt as a biofuel to produce electricity and thermal energy. The electricity is used to power the slaughterhouse fridges and the thermal energy to produce hot water used for cleaning.

Transforming bio-degradable waste into clean energy that powers the machines at the slaughterhouse is a windfall that has allowed SOGAS to significantly improve its competitiveness in the sector. The company has been able to cut its monthly electricity bill by 70 per cent, as well as reduce the amount it previously paid in taxes related to pollution. The bio-gas process also provides SOGAS with by-products, such as natural fertilizer, which form an extra source of income for the company. The reduction in wastewater and bio-waste also helps lower greenhouse gas emissions.

During a visit to the Dakar slaughterhouse in early 2014, UNIDO’s Director General LI Yong complimented SOGAS on its achievement. “Harnessing its own production waste, SOGAS recycles everything and throws away nothing. It is a good example of sustainable industrial development in the field of small and medium-sized enterprises. It is a company of the future,” said LI Yong. 

The SOGAS/BMN project was the first of its kind implemented as part of UNIDO’s Industrial Upgrading and Modernization Programme in the sub-Saharan region. UNIDO’s project manager, Smail Alhilali, said, “UNIDO’s programme via the BMN has offered technical assistance and financial incentives for enterprises to adopt new technologies and management practices. The success of SOGAS suggests that our programme is useful in safeguarding the environment and enhancing industrial energy efficiency in the country.” 

For more information, please contact:

Smail Alhilal,
Industrial Development Officer, Environment Management Branch, UNIDO


By ZHONG Xingfei and Charles Arthur
Posted September 2014