Nguyen Ha, Ngo Quoc Phong, Thi Le, Oanh, Nguyen Hai, Drangert Jan-Olof
2016 unpublished
Wastes from the sugar industry have negative impact on water steams and aquatic life as well as profitability. This is especially worrying for sugar companies using backward technology and non-integrated processes. A Material Flow Analysis (MFA) can together with the waste hierarchy help to reduce wastage and improve recycling and material resource management. Rather than adding end of pipe pollution control technology, a change to cleaner production processes and recycling lead to more
more » ... ble solutions that improve both the economic performance and the environment. To this end, the material flows at Hoa Binh Sugar Company (Hoasuco) in Vietnam is presented and analyzed. Results show that the loss of sugar added up to 17.1% of potential production. Solid flows from extraction, filtration and crystallization accounted for 10.6%; and the remaining 6.5% is lost in steam released from evaporation and crystallization. Clarification is the most inefficient process, with a sugar loss almost nine times greater than the benchmark value. On the other hand, Hoasuco lost 30% less of sugar left in molasses. Water usage in the Hoasuco was very high, ranging from 18 to 23m 3 per ton sugarcane of 15-20 L/kg of manufactured sugar compared to 0.5-0.9 m 3 /ton sugarcane reported in a World bank study and 4 L/kg of manufactured sugar in another studies. Based on these findings, the present study proposed various measures for cleaner production and recycling of waste: avoid mixing wastewater of very different composition to facilitate the treatment and recycling of each flow, both effluent and sludge. The solid waste fraction could be minimized by improved monitoring of the operations of processes. The solid waste should be reused and recycled (biogas extraction included), while incineration and landfilling should be avoided. The demand for water, cane and energy could be significantly reduced by such by measures.