wastewater as a resource, by dr. seneshaw tsegaye
TRANSCRIPT
Wastewater As a Resource
African Water Week
May 27, 2014 Dakar, Senegal
Dr. Seneshaw TsegayeAssistant Professor
Patel College of Global Sustainability UNIVERSITY OF SOUTH FLORIDA
Urban Policy & Governance
Social Resiliency and Health
Communicating Science in Sustainable Communities
Urban Planning and Design
Energy Systems
Urban Water
Urban Transport
Patel College of Global Sustainability -Academic Areas
In many countries of sub-Saharan Africa sanitation coverage is below 50 percent
How do we design our systems so that we can capture
Public health
Wastewater as a burden
Wastewater as a resource
?
Sanitation can’t be looked separately: Integration is a key
Source: CSIRO
Surface water
Demand management
Leakage management
Stormwater/ Rainwater
Used water recycling
Greywaterreuse
Cascading water use
Desalination
Groundwater
Energy & nutrient
Copyright © 2009 International Water Association
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OrganicMatter
Nutrients
We need a new perspective on sanitation - Beneficiation
Copyright © 2009 International Water Association
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Think about Harvesting Nutrients from Wastewater
Billions
Less Developed Regions
More Developed RegionsFull-scale struvite production facility
West Boise Canada (Pharmer Engineering)Struvite as commercial fertilizer
www.pharmereng.com 2013 (Ostara)
Great ideas to recover nutrient from water cycle
Great ideas to recover nutrient from water cycle, Durban
Fecal sludge into safe fertilizer: LaDePa machine
Entrepreneurs see the potential India, Malawi…..
Collection, transport, treatment and reuse-system (GTZ,2009)
Copyright © 2009 International Water Association
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We need a new perspective on sanitation - Beneficiation
Business oriented solution, Naivasha, Kenya
Business oriented solution: Lavatory and wastewater treatment plant with installed biogas generation facility
Public Toilet & Shower Cafe (Biogas for cooking)
NSWC, Kampala (Uganda): NAKIVUBO WASTE WATER TREATMENT PLANT CONSTRUCTION
AfDB Loan - treatment: • 45,000 m3/day waste water• 15,200 kg/day BOD
Energy production:Biogas holding tank: 2,900 m3Combined biogas and heat power station: 2 x 280 kWh
Source: NSWC / AfDB 2010
Thermal energy from groundwater
MITIGATIONHarvesting to provide greater security
New Business Model for Water Utilities- Hamburg Water Cycle
Business opportunities:
• Potential to recover and sell energy
• Potential to recover and sell nutrients
• Position of utility on the market as operator of decentralized treatment systems on district and household scale
• Exporting technology and expertise to quick growing Asian cities
• International consultancy
Decentralized system with source separation/ Vacuum sanitation
CHP
Heat exchanger in sewers
MITIGATION
Harvesting heat from sewers
Dalian-Xinghai (China) : Environment-friendly heating and cooling
Copyright © 2009 International Water Association
0%
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BOD5 Nitrogen Phosphorus Potassium
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We need a new perspective on sanitation - Beneficiation
Copyright © 2009 International Water Association
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Think about Reusing/Recycling
H2O
Fresh Water Supply
Waste Water
Small Water
Consuming
Industry
Fresh Water Source
Waste Water from
Durban City
Reuse of Water
[Reduction in Wastewater
discharge @10%]
[7% (47.50 Ml/d) of City’s
Current Demand ]
[Ehekwini Water Services:
Build on PPP Concept]
Entrepreneurs see the harvesting potential, Durban
Harvesting for agriculture
• 400M m3 treated wastewater used for agriculture in Beijing in 2010 (reduce peri-urban poverty and improve food security)
We need to move away from traditional thinking
Driver for water management should be beneficiation –maximize
value added
We need to harness the opportunities and make it work for all
