On Water... Treating Flowback and Produced Water Part 1

A severe criticism leveled at industry (and me frankly) has been that the water resources used in hydraulic fracturing where not being treated and are difficult if not impossible to economically treat. In response to these criticisms I felt that it was important to lay out to the readers some of the issues related to frack water and the types of treatment that are NOW being used in the field. This is a voluminous subject so I will break it down into the constituent parts and take on each section in a post. The key contaminants in frack water are:

Total Dissolved Solids (essentially, salt)

Free hydrocarbons (natural petroleum like substances in very low concentrations)

Dissolved hydrocarbons (same as above, but actually dissolved in the water)

Heavy Metals (low concentrations of naturally occurring metals in the geologic formation brought up by hydraulic fracturing)

Frack Chemicals (those chemicals added in VERY low concentrations to aid in the fracturing of the shale)

Suspended Solids (sand and fine particulate matter)

For today, let's deal with TDS.

The problem with the level of TDS in Marcellus Shale water can be boiled down to a single word: concentration. The TDS levels in most Marcellus Shale flowback waters are extremely high and near that of concentrated brine (from 100,000 to 250,000 parts per million, or 10 to 25%). This is obviously very high and not conducive for treatment using typical technologies such as filtration or even reverse osmosis.

But, the high concentrations are somewhat advantageous in that some crystalization and or evaporation technologies work more efficiently at high concentrations (i.e. less water to drive off). As such, a number of firms in the shale are testing and utilizing these technologies right now. Since no definitive discharge concentrations have been released by the regulators, no standard of treatment has yet to be determined.

The crystalizer or evaporator works as easily as it sounds, energy is consumed to drive off the water and the salt material is left behind, either has a solid or as a dramatically reduced brine that can be recycled. In some cases the water is collected or recovered, therefore the facility has zero air emissions. NGInnovations of Charleston WV has patented this technology and early trials are promising. There are a number of firms performing this work both on-site and free standing facilities located throughout the Appalachian Basin, including 212 Resources, Intevras, Fountain Quail and others.

Energy is a key component of the cost to recovery the brine, but as of this writing those technologies appear to be within the market price of water disposal. One ideal synergy is often that the gas from the well or an adjoining well can be used as the energy source, thus reducing the overall cost to treat the flowback water.

It should be noted however that many E&P firms have begun programs to begin reusing existing flowback water for additional hydraulic fracturing projects. This recycling reduces the net water needs in the Marcellus shale and takes trucks off of the roads (those trucks that would take the water for disposal and bring back fresh). Some water treatment must still be done, but at a greatly reduced price if the TDS is allowed to remain in tact.

The issue of high TDS is one that once again the industry is up to solving. A combination of recycling and treatment (both on-site and off) will allow for future development in the Marcellus Shale.



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Comment by Chen Xiaogang on August 23, 2011 at 12:58am
thanks！do you  have about shale gas of  its flowback？
Comment by Jamotom on June 21, 2011 at 4:18am
Michael, or any knowledgeable sources, I hope that you will add to this discussion with any contemporary (6/11) information concerning how flowback will and is being handled in Oh., Pa., & W.V., etc. Do you see any clear winning solutions on the horizon? I find the topic consuming because of the ramifications of finding a solution that is good for the environment and financially digestable by the industry, thereby allowing the industry to continue.
Comment by Larry Jackson on October 21, 2010 at 4:13pm
Michael, I work for Fountain Quail. I'd like to send you some more info on the company and what we do. We're not just running demo sites, but we are recycling 300K gallons of flowback and produced water per day at our facility in the Marcellus. Would you please email me at ljackson@fountainquail.com? Thanks.
Comment by Michael Havelka on June 8, 2010 at 9:49am
I will updating the chemicals portion in my Wednesday post (tomorrow). What I can say is that 99.5% of the frac fluid is water and sand. The remainder 0.5% is a mixture of chemicals (mostly inert) used to provide properties to the frac fluid that densifies and also changes the surface tension of the fluid to reduce friction and get the water and sand out into the formation in an optimal manner. Again... more later!
Comment by Denny D on June 7, 2010 at 12:35pm
Michael, very informative. Thank you! Looking forward to your understanding of the Frack chemicals. I imagine you likely don't have or can't reveal the exact chemicals/compositions but I find it interesting that you say they are used in "very low concentrations". Understand I'm not questioning that statement just don't understand what exactly the chemicals are actually accomplishing - why are they needed? Anyway, thanks again for your informative posts. I appreciate the education.
Comment by Michael Havelka on June 2, 2010 at 9:37am
@Dave... we are seeing concentrations over 200,000 ppm throughout the shale. The Northeast part of PA, it is a bit lower, but really all over the map. We just received samples from that area at 188,000 ppm.
Comment by Dave Cornue on June 2, 2010 at 9:31am
What are the maximum TDS concentrations that producers are seeing the Marcellus? Particularly in the norhtern counties of PA.
Comment by rich myers on June 1, 2010 at 10:03am
All the talk of technology is interesting, however, it is still occuring after the fact. Just like the reprocessing debate over nuclear waste. Let's create a mountain or lake of this stuff and then figure out a way to get rid of it. Unfortunately the "frack" water is still being dumped on municipal wastewater plants that are not equiped to deal with the "product". Simple solution, get your waste treatment process in place before you create the waste. We don't need any more "legacy industries" like coal that trashed the countryside and then folded up and disappeared leaving the rest of us (taxpayers) to clean up their mess.
Comment by Brian Oram, PG on May 30, 2010 at 5:22am
I am hosting an energy expo in June 2010 at the Luzerne County Fairgrounds - Dallas, PA - Would be great to have information about the product
http://www.pnesolutions.org/energy_expo.htm

Also would like to see units - any contacts??
Comment by Michael Havelka on May 26, 2010 at 1:22pm
Deborah

Great questions...

Question 1... yes, both Fountain Quail and 212 Resources are running demonstration type systems now, and as I said with somewhat mixed results. It is not a matter of "not working" rather more of just trying to fine tune things and get things operating efficiently. The other company I mentioned is building the first on-site unit right now, but have done small demonstration projects with much success.

As for the emissions issues, the volatile chemicals are removed prior to any crystalization or evaporation. These items are VERY easy to remove as I will note on my next post and not nearly as costly as TDS removal. Also the NGI system recovers the water for reuse (with volatile organics and metals removed). There are no air emissions from the system.

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