Shock-Wave Electrodialysis By

Slithery Snakes

Aymeric Alejo-Chaban – AymericAlejo@psu.edu

Nick Decandia - nld5154@psu.edu

Faisal Almemari - fha2@psu.edu

Khalifa Almheiri - kfa5157@psu.edu

EDSGN 100 – 013

Dr. Sarah Ritter

12/2/2016

Executive Summary –

Starting in mid-November, Chevron approached the Slithery Snakes and tasked the

group with identifying a solution regarding the treatment of brine water created in the fracking

process. By doing so, we would eliminate significantly the environmental impact fracking has as

well as preventing Chevron from spending egregious amounts of money on rebuying fresh

water. This is because by neglecting the treatment of water previously, Chevron would

consistently need to rebuy freshwater to continue fracking as it is used to transport the oil or

gas back up to the surface (Chevron). After a lengthy design process, the Slithery Snakes

decided to use shock wave electrodialysis to treat the brine water. This procedure purified the

byproduct at a rate of 99% effectiveness which proved to satisfy the needs and requests of the

energy corporation.

Introduction and Problem Statement –

The Slithery Snakes, at the request of Chevron, would like to develop a process which

treats the 400 barrels of brine water created a day by the fracking process (Chevron). Currently,

the contaminated water is stored deep underground, away from any bodies of water which

could possibly become contaminated. However, natural pores in the rock formations introduces

the slight possibility of the brine water reaching those sources of freshwater. In addition, the

increase in pressure caused by the injection of brine water deep underground increases the

likelihood of an earthquake. As a result, our project will explore different methods which could

be used to develop the contaminated water into a usable product while avoiding the possible

dilemmas caused by not treating the water. Furthermore, the project will aim to minimize the

amount of economic resources spent while maximizing the effectiveness of the solution in

regards to solving the designated problem.

Definition of Sustainability –

Sustainability, in engineering, is the process of designing systems or solutions that have

do not have any long term detrimental effects on the environment or natural resources. In

terms of shale development, sustainable solutions will be energy efficient and will not damage

the ecosystem in the area.

Background –

Currently Chevron and most other companies use deep injection wells to store the

byproduct wastewater (Chevron). These wells consist of a system of concrete and steel tubes

that open up into a natural rock formation. Although the water is disposed of deep beneath the

surface of the Earth, the brine water is still able to seep through the rock polluting the area

around it. This method of disposal may seem like the most feasible and cost effective compared

to treating it or burning it, but its long term effects will facilitate environmental problems such

as contaminating nearby bodies of water and increasing the likelihood of earthquakes. The

storage of wastewater in deep injection wells can raise pressure levels in areas around the well

predisposing them to earthquakes where faults are present. This has been shown in Oklahoma

where their increase of deep injection wells caused them to surpass California as the state with

the most amount of earthquakes in 2015 (Schaefer).

Customer Needs –

Chevron had a number of needs it conveyed to the Slithery Snakes. However, the group

chose to prioritize only a couple which first included a product that treated the water onsite to

produce a marketable byproduct. In addition, the group gave precedence to needs such as that

the process must be sustainable, environmentally friendly, and be safe to operate by Chevron’s

employees. The reason we chose to prioritize on-site treatment and ease of use was because

the most important reason for treating the contaminated water was to recycle the freshwater

back into the fracking process. Hence, having the process operate on-site would erase the need

for transportation, making the process easier and less complex. Moreover, the salts found in

the water could then be marketable to create additional revenue for Chevron. In regards to

sustainability and environmental friendliness, this was most important because the process

must not incur additional strain on the environment which may pose possible health risks to

both humans and other species. Finally, the process must be safe to use as the health of the

employees are necessary to continue the operation of the company.

Figure 1: AHP Matrix used to compare relative importance of customer needs

Concept Generation –

After reviewing the needs of Chevron, the Slithery Snakes conducted research in able to

determine methods to threat the brine water created by the fracking process. Our query

resulted in a number of processes such as treating the contaminated water with silver,

compressed carbon, reverse osmosis and shock wave electrodialysis. The first technique,

involving the use of silver (Figure 2), purifies the water because of its anti-microbial properties

(The Silver Institute). However, this is ineffective in regards to fracking as the problem isn’t

microbes but the contamination of salt and chemical additives. The second technique involving

the use of compressed carbon to cleanse the water (Figure 3). Explicitly, by creating a carbon

filter which reduces lower molecular weight organics such as pesticides and chemicals found in

industrial waste. This method would prove effective in treating the brine water as the salt

molecules found in it would be caught in the membrane. Nevertheless, the constant use of the

filter would require it to be consistently replaced. The third procedure found was reverse

osmosis (Figure 3). This process encompasses the use of osmotic pressure to pass a solvent

through a porous membrane (How Stuff Works). Hence, the filtration of large molecules such as

the salts found in the brine water. This process would be very effective in the treatment of the

contaminated brine water. However, it would also require for the filter to consistently filtered.

The final process researched was shock wave electrodialysis (Figure 4). A process which purifies

freshwater by utilizing an electrically generated shockwave to push the salt, chemical additives,

and water through a porous membrane (Bazant). However, only the water is small enough to

pass through the small openings between the glass frit. As a result, the water on the other side

of the filter is completely rid of the salt and chemical additives found in brine water. In addition,

because the water is running along the membrane, it is unable to be clogged up and does not

require the filter to be constantly replaced as found in reverse osmosis or through the use of

the carbon filter.

Figure 2: Use of silver to purify brine water directly in the pond

Figure 3: Sketch demonstrating the use of reverse osmosis or a carbon filter to treat the water

Figure 4: Sketch demonstrating the use of shockwave electrodialysis to treat brine water

Concept Selection –

After careful consideration and through the use of a concept scoring matrix (Figure 5),

the method of shockwave electrodialysis was chosen to treat the brine water produced by the

fracking process. This was largely due to its ability to meet consumer needs such as

environmental friendliness and sustainability where other processes could not. For instance,

methods such as the use of silver or compressed carbon filters posed a risk to the environment.

In the case of the silver, there was a possibility of the silver entering the ground which could

harm the prospects of plant growth as well as the possibility of entering nearby bodies of

water. As for the compressed carbon filter, the process posed a threat to the environment

because when the filter would need to be replaced, disposing of them could potentially harm

the environment. Finally, reverse osmosis and shockwave electrodialysis were very similar in

their effectiveness to purify the brine water while maintaining environmental friendliness.

However, reverse osmosis was more expensive because of the need to replace the clogged

permeable filters. Thus, the Slithery Snakes chose to use and develop shockwave electrodialysis

to process the brine water for Chevron.

Figure 5: Concept scoring matrix used to compare each possible designs strengths and

weaknesses in regards to the needs outlined by our customer Chevron.

Concept Development –

Our initial shockwave electrodialysis design worked by utilizing an electrically generated

shockwave to push the salt, chemical additives and water through a porous membrane.

However, only the water is small enough to pass through the small openings between the glass

frit. As a result, the water on the other side of the filter is completely rid of the salt and

chemical additives found in brine water. Once we developed our initial design, to enhance the

system, the Slithery Snakes gave team number 8 the design and asked them for their feedback.

The group reviewing the proposal advised the Slithery Snakes team to consider harvesting

hydroelectric power from the water running through the system. After hearing this suggestion,

the team agreed that the idea involving using a turbine to harvest hydroelectric power would

be feasible and would greatly improve the benefits of the system. As a result, the Slithery

Snakes implemented it into the final design.

Prototype:

Figure 6: Sketch demonstrating the use of shockwave electrodialysis to treat brine water

Figure 7: Prototype built by the Slithery Snakes to parallel the concept of shockwave

electrodialysis.

The prototype that the Slithery Snakes made shows the section where the brine water

undergoes shockwave electrodialysis. The steel pipe is represented by a PVC pipe. In regards

to the cathode and anode which produces the electromagnetic shockwave, the brown cardboard

pieces are used to demonstrate both. Finally, the porous filter which is specifically the glass frit

is represented using a metal mesh. This prototype meets the design criteria because its

relatively simple and does not require constant operation by Chevron employees. Moreover, it is

relatively small and meets the requirements of being operate onsite as it does not need large

areas to be used. Finally, it meets the requirement of economic sustainability as all of the

materials can be broken down and recycled for other purposes. In the case of the steel used for

the pipe and cathode/anode, this can be belted down. As for the glass frit, it can also be melted

down.

Final Design –

Figure 8: Solidworks rendering of final design

Figure 9: Solidworks rendering of final design

Our shockwave electrodialysis process can be broken down into a number of steps.

First, the brine water flows down the pipe as a result of gravity. This is because the system will

be built at an angle to remove the need for a pump. As it flows down, it will pass through a

turbine found at the beginning of the pipe to generate the 1 volt of electricity needed to

generate the electromagnetic shockwave. This allows the process to be sustainable as well.

Next, the cathode and anode are charged using the electricity generated by the turbine and the

shockwave is then created. This pushes the brine water to the right and filters the water. This is

because the water is small enough to pass through the glass frit while the salts and chemical

additives cannot. Finally, the fresh water is separated by passing through a pipe that moves

away from the system while the salt and chemical additives move through an additional pipe

moving to an alternate direction. The pipe carrying the freshwater travels back to the fracking

pad to be reused. In the case of the salt and chemical additives, they travel to a processing

facility to be marketed. The process was measured to filter 99% of the brine water which is

extremely effective. The model also addresses the risks posed by the current solution Chevron

uses which is the injection wells. The current process presents considerable risks to the

environment such as contamination of other bodies of water as well as increasing the likelihood

of earthquakes. In contrast, the shockwave electrodialysis model is environmentally friendly

and even benefits the environment by removing the need to continuously use more freshwater

as it can be recycled. In addition, the process is relatively cheap (Figure 10) compared to the

cost of buying freshwater which costs around $8 million dollars per fracking well (Schaefer).

Furthermore, the design meets operating safety regulations as it does not require Chevron

employees to operate it. Hence, removing the risk of them being injured. Finally, the process

works rather quickly as the water is processed by moving through the filter. Thus, it does not

incur a large amount of time on the fracking process.

Figure 10: Cost of operating the shockwave electrodialysis process

Conclusion –

Our product has much more benefits than it does drawbacks. Once the system is fully

set up, the costs to maintain it are relatively cheap. Next, the porous material that is used to

separate the brine water from the fresh water never needs to be replaced. The battery used

operates at a low voltage so the replacement of it is not expensive. The most expensive

component to the system is the turbine which serves the purpose of generating power to

operate the process. Without the turbine, the process would require additional energy so the

turbine has immediate benefits. Another key advantage to our solution is that it does not

damage the environment in any way. Many methods used by fracking companies can be

detrimental to the ecosystem around it by polluting nearby bodies of water. Our proposed way

will reuse the clean water for fracking leaving no potential for pollution. Moving forward, this

design can be tested on the treatment of just about any liquid that has contaminants making it

impure. From this project our group has learned about the overall fracking process and

alternative options for the treatment of brine water. This project has also taught us ways to

analyze different methods to determine which one would be the best solution to the problem

at hand.

References –

1. Bazant, Martin Z., Sven Schlumberger, Nancy B. Lu, and Matthew E. Suss. "Scalable and

Continuous Water Deionization by Shock Electrodialysis." Scalable and Continuous Water

Deionization by Shock Electrodialysis (2015): n. pag. ACS Publications. Web.

<http://pubs.acs.org/doi/abs/10.1021/acs.estlett.5b00303?journalCode=estlcu&>.

2. "Carbon Filtration." USPW. N.p., n.d. Web. 11 Dec. 2016.

3. "Chevron Shale Production." Chevron.com. N.p., n.d. Web. 11 Dec. 2016.

4. “Reverse Osmosis” HowStuffWorks Science. HowStuffWorks, n.d. Web. 11 Dec. 2016.

5. Schaefer, Keith. "Fracking and Water: A New Way To Profit from the Industry's Biggest

Problem." OilPrice.com. N.p., 14 Feb. 2012. Web. 11 Dec. 2016.

6. "Silver in Water Purification | The Silver Institute." The Silver Institute. N.p., n.d. Web.

11 Dec. 2016.