Desal 1

Question 0

What is the salt content of sea water?

Answer 0

35,000 ppm

Question 1

How many gallons of water does it take to support a population of 1,000,000?

Answer 1

40 billion gallons for every 1 million people.

Question 2

To what ppm does desalination decrease salt content in sea water?

Answer 2

To 1,000 ppm from 35,000 ppm

Question 3

What is the core process in the desalination process?

Answer 3

Desalination decreases salt content from 35,000 ppm to 1,000 ppm by forcing the salt water at high pressure through a filter with holes that are 1/100,000th the size of a human hair

Question 4

How much salt is produced in the process of desalinating 40 billion gallons of water?

Answer 4

10 million tons of salt

10MM tons of salt: 5% global salt market

Question 5

How many tons of gypsum does desalinating 40 billion gallons of water produce?

Answer 5

650,000 tons of gypsum

Question 6

What is the percentage of salt content in seawater?

Answer 6

3%

Question 7

What is the percentage of salt content in desalination reject?

Answer 7

6%-7%

Question 8

What advantage does desalination reject have over traditional seawater in the salt crystalization process?

Answer 8

Because desal reject contains 6%-7% salt concentration compared with 3% for seawater, it can be crystallized through the solar evaporation process using half the space.

Question 9

At what concentration percentage does salt crystalize?

Answer 9

26%

Question 10

What is the more costly salt crystallization process between solar pond and thermal?

Answer 10

Solar is less expensive. Thermal requires expensive machinery.

Question 11

How does the cost of desalinated water compare to other new water sources like brackish and recycled water?

Answer 11

San Diego County did a study and found that desalinated water is comparable in cost.

Question 12

How does desalination compare in cost to existing water sources?

Answer 12

It is about twice as expensive.

Question 13

How much of a reduction in product water production occurs for every 1 degree Celsius decrease in intake water temperature?

Answer 13

3% reduction in output for every 1 degree C decrease

Question 14

What adjustments can be made to offset production losses related to decreases in intake water temperature?

Answer 14

1. Accepting lower production targets
2. Adding facility capacity
3. Increasing feed-water pressure (energy use increases 3% to compensate for every 1 degree C decrease in water temperature)

Question 15

How is energy use correlated to seawater salinity?

Answer 15

With higher seawater salinity, membranes with lower water permeability must be selected. The lower the water permeability of the membrane, the higher the pressure and the higher the energy costs.

Question 16

How much energy is required to desalinate 1 cubic meter (264.172 gallons)?

Answer 16

0.86kWh

Question 17

How much energy is required to desalinate 40 billion gallons?

Answer 17

130,218,191 kWh
130,218 mWh
130.21 gWh