Sustainable Energy Saving in Wastewater Treatment

1. Sustainability and Energy Saving In Wastewater Treatment • 07 Dec 2011

2. Introduction • The first decade of 21st century has been an explosive growth in attention given to energy savings and sustainable management of resources. • One of sustainability definitions is “Development that meets the needs of present without compromising the ability of future generations to meet their own needs” , other definition is “Our common future”.

3. Volatile energy prices and concerns about global climate change “Carbon print” and green gases (GHGs) have resulted in increasing security of operations and emissions from numerous resources. • Water and wastewater facilities is one of the major consumers of the energy. • Wastewater utilities are estimated to be top 10 types of industries for emissions of GHGs. • Energy saving and sustainability have become common best business practices.

4. The National Water Company (NWC) has adopted a strategy for sustainable management which promotes utilization of environmental friendly resources and renewable energy.

5. NWC Sewage Treatment Technology Strategy The pillars of NWC sewage treatment strategy targets development of a new generation of sewage treatment plants. NWC perceives STPs as three-resource production factories in one site: • Water factory • Heat and power generation factory • Nutrients factory

6. NWC has initiated two STPs with combined heat and power generation units in the Kingdom of Saudi Arabia : • Initiated the construction of the first STP in kingdom of Saudi Arabia in Al-KHARJ road , that will serve the city of Riyadh with capacity of 200,000 m3/day. • Initiated the procurement one of the largest STP in middle east (Airport 2- STP) ,that would serve the city of Jeddah with a target capacity of 500,000 m3/day

7. Al-KHARJ Road STP

8. Al-KHARJ Road STP

9. Al-KHARJ Road STP

10. AL-KHARJ STP Units Main components of Al-Kharj STP: • Preliminary treatment unit • Secondary treatment unit • Tertiary treatment unit • Sludge digestion and bio-gas generation unit • Sludge Dewatering • Combined heat and power generation • Odor treatment unit • Monitoring and Control (SCADA)

11. Benefits of STP with Combined Heat and Power Generation This type of energy recovery from wastewater is considered an environmentally friendly solution that has many advantages including: • Production of renewable energy (in Al-Kharj 2.2- 2.5 MW). • Short duration to return on investment (in Al-Kharj 6 years of payback time) • Reducing of carbon emissions which yield financial return and improve the Kingdom’s image on the sustainability front.

12. Benefits of STP with Combined Heat and Power Generation (cont.) • Reduction in cost of chemicals. • Reduction in cost of sludge disposal • Reduce the impact of sludge on the environment. • Production of high-quality sludge • Utilization of thermal energy produced from the system to reduce the cost of processing and transportation of sludge • Independence of large parts of the STP in terms of use of energy produced from the plant

13. Benefits of STP with Combined Heat and Power Generation (cont.) 10-Support the development and implementation of environmental solutions on a Kingdom wide level. 11-Reduce the pressure on industrial sources of electricity

14. NWC Strategy & Commitment to Sustainability • These projects confirm the commitment of NWC towards sustainable management through the utilization of environmental friendly resources and renewable energy.

15. THANK YOU