Presentation on theme: "Jac Wilsenach Appropriate technologies conference 4 September 2007 BMW Pavilion, V&A Waterfront, Cape Town On-site treatment and beneficial use of waste."— Presentation transcript:
Jac Wilsenach Appropriate technologies conference 4 September 2007 BMW Pavilion, V&A Waterfront, Cape Town On-site treatment and beneficial use of waste streams: local case studies
Challenges! 1)Dry region vs sustainable food production 2)Economic growth vs environmental protection 2) Ageing infrastructure vs urbanization 3) Lack of skills vs global development 4) Poverty vs wealth 5) Sustainable systems vs depletion of resources
The Businessplace at Philippi 300 – 400 houses, Small enterprises, 7 ha urban agriculture
The Philippi Business Place A multidisciplinary neighbourhood design approach with: Sustainability Institute, School of Public Management and Planning, University of Stellenbosch Noero Wolff Architects Agama Energy CSIR TRIACON Hulme and de Villiers Etc.
Aerobic biofilm Anaerob. Digester Offices/ houses Sand filter UV Municipal water (171 m 3 /d) Recycle to toilet flushing (103 m 3 /d) Compost/ Irrigation on site N2N2 Grey water (171 m3/d) Treatment processes at Philippi - Water Balance Aerobic biofilm Anoxic MLSS Biogas Black water (103 m3/d) Ground water (29 m 3 /d)
Net Food import Wastewater treatment (including bio- denitrification) Agricultural soil needs: 11750 kgN/a 1625 kgP/a 1450 kgN/a 1625 kgP/a 10300 kgN 2 /a 1450 kgN/a 1575 kgP/a Food consumption and excretion (2500 people) (Based on tomatoes) Local over-supply of nutrients (N)
Aerobic biofilm Anaerob. Digester Offices/ houses Sand filter UV Recycle to toilet flushing (103 m 3 /d) Compost/ Irrigation on site 28 kgN 2 Grey water 139 kgCOD/d 5 kgN/d Treatment processes at Philippi – Mass Balance Aerobic biofilm Anoxic MLSS 18 kgCH 4 Black water 208 kgCOD/d 32 kgN/d 7:1 4 kgN/d 5 kgN/d
Oude Molen EcoVillage development Projexe, Makeka Design Laboratory, Marcussen Architecture, Arcus Gibb, Triocon, Sustainability Institute, Heritage consultant, Environmental consultants,
Aerobic biofilm Offices/ social/ Comm./ Showcase/ houses Sand filter UV Recycle to toilet flushing (45 m 3 /d) Compost/Struvite Exported off site Bath/Shower water 50 m 3 /d Treatment processes at Oude Molen Aerobic/ Anoxic SBR UCT MLSS Black water kitchen water laundry water 189 m 3 /d Urine 1 m 3 /d Irrigation Municipal water 195 m 3 /d MgO
Costs Capital cost of Lynedoch system = R15,000/home (2001) Capital cost of Philippi system = R16,000/home (2006), water saving = R630/home.a Cost to replace/upgrade overloaded infrastructure @ Oude Molen = R 75 mil. (R175,000/home, 2004) Reference: N2 Gateway = R15,000/home for water and sanitation infrastructure
Conclusion… a place for decentral systems: Where in terms of relative scale, it is “central” Where central systems fail to keep up with development, Where development takes place on top of and over original design capacity, Where communities can tap into the recycled resources, Where ownership of operation and maintenance can be established.