Session 4

Advanced Material Flow Analysis for Food Processing Trade Villages for Environmental and Resource Management in Red River Delta, Vietnam
Nguyet Tran, Dirk Weichgrebe, Karl-Heinz Rosenwinkel
Institute for Sanitary Engineering and Waste Management, Germany

Since the Doi Moi or renovation policy of Vietnamese government in late 1980s, the food processing trade villages, type of home-based production, have been rapidly developed as one of the ways to eliminate poverty in rural areas. However, they have been causing alarming environmental degradation since beginning of 2000s.
This research investigated the food processing villages in Red River Delta. The study applies advanced methods of Material Flow Analysis (MFA) with uncertainty analysis, functions of gross error detection and data reconciliation from tailor-made MFA software “STAN”. The target productions are starch, liquor, rice vermicelli, rice noodle, glass noodle; related anthropogenic processes are household sanitation systems, rice farming and pig rising.
The results of balance in 2015 for these productions show that, material cycles are almost linear and low resource efficiency. At bulk material level, they produced 9.6 million cm3 wastewater, which accounts for more than 90 percent (%) of water consumption and one million tons of solid residues. About 0.5% of total wastewater and 50% of solid residues are recycled as animal feeds; the rest is almost discharged untreated to sewer. At the substance level, more than 10000 tons of organic carbon (TOC), 1700 tons of nitrogen (TN) and 400 tons of phosphorus (TP) which accounts for 27%, 60% and 77% of TOC, TN, TP, respectively, in input materials were released in wastewater and solid residues. Only 27% of TN, 21% of TP and 36% of TOC in these production emissions are recycled. The village sewers are becoming “reactor” for these pollutants. They are later conducted to local surface water which is seriously in eutrophic condition.
To achieve sustainable productions as well as sound management of environment and resource efficiency, the material cycle should be closed by mean of symbiosis within productions themselves and related anthropogenic processes.