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ABENGOA WATER

Red Tide Event Prevention and Influence on Desalinated Water Production Cost

8-9 February, 2012 Muscat – Sultanate of Oman

Innovative Technology Solutions for Sustainability

Index:

Red tide origin

Abengoa Water experience

Desalinated water cost case study

Other options

Red Tide Event Prevention and Influence on Desalinated Water Production Cost

Red tides: harmful algal blooms (HABs) that occurs when toxic microscopic algae in seawater proliferate to higher than normal concentration.

While are known that contribute to HABs, how these factors come together to create a bloom of algae are not yet well understood.

Sometimes, HABs occurs when nutrients from sources such as lawns and farmlands reach the sea and build up at a rate that overfeeds the algae that exist normally in the environment.

Color depend which of the three primary types of phytoplankton are responsible for the problem: dinoflagellates, diatoms or blue-green algae.

Of more than 4000 marine phytoplankton species only 50 to 60 are believed to be toxic.

Scientific studies indicate a global increase in

occurrence and geographic extent of harmful

red tides

Red Tide Event Prevention and Influence on Desalinated Water Production Cost

Qingdao Algae Bloom Experience

Qingdao Algae Bloom Experience

Qingdao Algae Bloom Experience

Qingdao Algae Bloom Experience

Turbidity: normal range 2-5 NTU, severe increase to 15 NTU during algae period

TMP: normal range 0.2-0.3, temporary increase to 0.4-0.5 bar during algae period

Permeability: normal range 300-500 lmh/bar, temporary drop to 200-300 lmh/bar during algae period

Fe dosing: normally 0 mg/l, temporary increase to max. 1 mg/l during algae period

Qingdao Algae Bloom Experience

Plant capacity 100.000 m3/day

22,0 MIGD

35 Hm3/year

7.701 MIG

Avalability 350 days/year

Desalinated water production cost. Basic case study.

Case study:

Pretreatment design based on DAF + UF

Desalinated water production cost. Basic case study.

Financial data

Equity 25%

Debt 75%

Interest rate 6%

Period of debt return 15 years

Period of construction 2 years

Period of operation 25 years

Desalinated water cost. Basic case Study

Cost increase due to pretreatment improvement

Structural cost increase due to DAF

0,03 to 0,04 €/m3

1 to 1,4 M€/year

Cost increase with DAF in operation

0,05 to 0,06 €/m3

Other options to consider

Alternatives to minimize red tides effects in Desalination Plants:

Non surface intake systems: vertical beach wells, radial wells infiltration, engineered infiltration galleries

Global water network connected with alternative sources

Partial open intakes / non surface intakes

Plant monitoring preventive management

Avoiding areas with existing sewage or industrial discharges. Nutrients reduction

UF membranes development and operational modes improvements

Innovative Technology Solutions for Sustainability

Thank you