Audio Script
CU-Boulder technology could make treatment and reuse of fracking wastewater cheaper and simpler
Feb. 24, 2015听听听听听听听听听听听听听听听听听听听听听听 Casey Forrestal/Zhiyong Jason Ren
听听听听听听听听听听听 Trying to treat the estimated 21 billion barrels of wastewater produced by oil and gas operations each year in the U.S. would be an expensive and time-intensive process.
听听听听听听听听听听听 But CU-Boulder technology could change that. 听University engineers have invented a simpler, cheaper process that can simultaneously remove both salts and organic contaminants from wastewater, all while producing additional energy, says Casey Forrestal, a CU-Boulder postdoctoral researcher in environmental and sustainability engineering.
CUT 1 鈥淲hat we do is, we use this fuel cell system that converts stored chemical energy which gets converted into electrical energy using micro-organisms and then that energy is then used to desalinate salt water 鈥� insitu -- meaning inside the reactor.鈥� (:22)
听听听听听听听听听听听 The new treatment technology, called 鈥榤icrobial capacitive desalination,鈥� uses microbes to feed on energy-rich hydrocarbons found in the wastewater. As they feed the microbes release energy that is used to create positively and negatively charged electrodes in the battery-like cell, says Forrestal.
CUT 2 鈥淭he way that the microbes work is they need to eat and breathe. Instead of breathing air just like we do, they actually breathe to an electrode -- to a solid surface that takes those electrons. (:16) And then this specialized fuel cell operates also in the same manner where it鈥檚 eating this food, the waste product, and then generating this electricity and we use oxygen from the air to complete the circuit to generate this electrical power.鈥� (:33)
听听听听听听听听听听听 Forrestal says the generated power is then used to remove the salts from the wastewater.
CUT 3 鈥淚t鈥檚 actually a two-step process where the microorganisms are actually generating the electricity and then we use the secondary process called 鈥榗apacitive deionization鈥� inside the reactor to remove the salts. (:14) So the microbes, per say, are not actually removing the salts, but they are generating the energy required to remove the salts.鈥� (:22)
听听听听听听听听听听听 The result is water clean enough to meet discharge standards and only another step way from being clean enough for agriculture use or even drinking water, says Forrestal. 听
CUT 4 鈥淭he water is not potable at that point coming out of the reactor but because we鈥檙e generating external electricity we can actually use secondary processes to treat the water to any level we need. It could be potable or for agricultural purposes.鈥� (:16)
听听听听听听听听听听听 If the water can be treated inexpensively enough, oil companies could reuse the water instead of injecting it into deep wells -- an expensive, environmentally sensitive and controversial practice -- says co-researcher Zhiyong Jason Ren, a CU-Boulder associate professor of environmental and sustainability engineering.
CUT 5 鈥淭he water is precious resource for everybody, including them, so they want to reuse the water as much as they can so they don鈥檛 need to buy fresh water every time and they don鈥檛 want to lose water permanently to deep wells. (:14) If we can help them reuse the water that saves them money.鈥� (:17)
听听听听听听听听听听听 Forrestal says the CU-Boulder research team came up with this simplified treatment system after investigating similar technologies.
CUT 6 鈥淧eople have been thinking about this issue for a long time and working on a lot of different technologies. What we did was we tried to come up with a way in which we could integrate some existing technologies into a single system that could then perform the desired function. (:18) We felt like we had a real interesting niche in that we generate the electricity ourselves and we can desalinate it.鈥� (:26)
听听听听听听听听听听听 To try and turn the technology into a commercial reality, Ren and Forrestal have co-founded a startup company called BioElectric Inc.
听听听听听听听听听听听 To determine if the technology offers a viable solution for oil and gas companies, the pair first has to show they can scale up the work they鈥檝e been doing in the lab to a size that would be useful in the field.
听听听听听听听听听听听 The cost to scale up the technology also needs to be competitive with what oil and gas companies are paying now to buy water to use for fracking, Forrestal said.
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