Unit 3.3 – Questions

1. The North Central states produced how many gallons of ethanol in 2010?

a. less than 6 billion gallons
b. nearly 12 billion gallons
c. over 25 billion gallons
d. just under 53 billion gallons


2. Which of the following processes in corn-grain ethanol dry mill processing uses the most water?

a. drying
b. cooling tower
c. boiler


3. Various surveys indicate that water use per gallon of ethanol produced has dropped from 5.8 gallons per gallon of ethanol in 1998, to 1.75 gallons per gallon of ethanol produced in 2008.

a. True
b. False


4. Consumptive water use in ethanol processing is defined as the following:

a. drinking water consumed by operators of the facility
b. water recycled and reused in a production facility
c. water lost to evaporation and discharge that is not returned for use
d. water withdrawn from a well


5. Zero Liquid Discharge includes which of the following (check all that apply):

a. diverting cooling tower water to the supply water tank
b. management changes, like recycle loops
c. allowing only a small fraction of steam to escape the system
d. treating the supply water tank as a blend tank


6. The greatest water use in the life-cycle of corn-grain ethanol is what?

a. water used in the processing facility
b. water consumed to grow the feedstock
c. water used to harvest, dry and deliver the grain
d. none of the above


7. It is estimated that 95 percent of all corn-grain ethanol is made with corn grown with what?

a. rain water
b. irrigation water
c. a combination of irrigation and rain water


8. Studies have shown that field-to-pump water use to produce one gallon of ethanol is what range?

a. 69 to 201 gallons of water per gallon of ethanol
b. 5 to 528 gallons of water per gallon of ethanol
c. 10,000 to 50,000 gallons of water per gallon of ethanol
d. over 100,000 gallons of water per gallon of ethanol


9. Embedded water in ethanol is greatest in what state?

a. Ohio
b. Kansas
c. Iowa
d. Nebraska


10. When cellulosic-based ethanol becomes economically viable, its production will likely be more water efficient for what reasons (check all that apply)?

a. woody and native species will be grown in adapted climates under rainfed conditions
b. processing facilities will adopt mature water reuse and recycling technologies
c. cellulosic conversion technology does not need water
d. none of the above


3.3 Answers