Recycling Flowback Water

Following on from my last post, How Much Is Too Much...Water Use In Fracking: An Introduction, you may have felt a little disheartened about the huge volumes of water used in hydraulic fracturing and the extent of negative impacts on the environment.

One problem traditionally associated with the recycling of flowback fluid, is that it has a strong tendency to return as brine-water- i.e. a highly saline solution. In the past, his has always been seen as a negative attribute and consequently past recycling of flowback fluids has been very limited. It is even common procedure among many energy companies to leave flowback fluids in open pits to evaporate...releasing harmful VOC's, carcinogenic compounds such as benzene and naturally occurring radioactive elements(http://www.dangersoffracking.com/). This has resulted in reported local atmospheric pollution, low-level ozone and acid rain.

Fracking flowback fluid, left to evaporate in an open pit

Image courtesy of Tom Wilber

Image URL: https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhke5Pf9h_BtaBBidLctrSXpR6m24Ip62_psM7EVVrJRlvxKwdIJ0hf_bV5UCrr84BwYeFoP44_DUiYhYn6FGjVq4FnvVrJa3oYAVzqVY9-x5QL-GLXbi-j9bZKkQMkJbY40wKwFIs9E_A/s1600/Fracking-pit-Helen-Slottje.jpg

However, fear not Frackers, there is a light at the end of the tunnel...This post is about the technologies currently in development for improved treatment and recycling of flowback fluids

A recent publication by the Society Of Petroleum Engineers (SPE) (http://www.speeurope.org.uk/), has recently detailed a report concluding a new use for the highly saline flowback fluid recovered from the ground after a fracking operation. The report was conducted by Haliburton and XTO Energy.

The Report is available here: (http://blog.ecologixsystems.com/wp-content/uploads/2013/04/Recycling-Produced-and-Flowback-Water-for-Fracking.pdf)
 The full reference is : Lebas.R. et al., February 2013, " Development and Use of High -TDS Recycled Produced Water for Crosslinked-Gel-Based Hydraulic Fracturing" SPE 163824

The real crux of this report is the discovery that a brine-enriched flowback fluid, which contained Total Dissolved Solids (TDS) at levels as high as 285,000 mg/L- which equates to 28.5% salinity - could be treated and reused. Even more importantly, the level of efficiency of this recycled fracking fluid was as high as that of traditional fracking fluid, generated from 100% fresh water. In this study, the brine flowback fluid was mixed with several chemical additives commonly used in drilling operations: Carboxymethyl Hydroxypropyl Guar Gum; a zirconium based cross linker; sodium chlorite breakers and non-emulsified surfactants. The result was a fracking fluid that had the required viscosity to effective transport proppants and yet, it was also slick enough to permeate micro-fractures in the target shale formation. Positive results were found in both lab studies and out in the field.

This revolutionary method was used in the Delaware Basin, New Mexico to complete 7 wells.

Furthermore, there were several other benefits from this new technique:

1. Fresh water reserves can be left untouched, for use in agricultural and commercial applications.
2. Can remove ~1400 trucks off the road; reducing congestion and reducing associated carbon footprint
3. Can replace the use of disposal wells and associated atmospheric pollution
4. Using brine-water actually increases productivity as it prevents clay molecules from swelling
5. This results in savings of up to ~ £50,000 per well.

This quote taken from the SPE publication is pretty definitive: 'The study shows that brine water possesses all the characteristics required for effective fracking: easy preparation, rapid hydration, low fluid loss, good proppant transport capacity, low pipe-friction and effective recovery from the reservoir...Simply put, salt water is good for fracking and any statements other-wise are unfounded'

The key step is now to convince energy companies to move from exploiting freshwater, which is unfortunately cheap clean and readily available. BUT...

With significant savings to be made and improved productivity, surely it makes sense to make the move to a more sustainable and environmentally friendly future?

Opposition to fracking operations is growing among the public domain...perhaps this is the answer to, at least one, of the negativities associated with fracking?

Perhaps, it is time for governing bodies to administer sanctions against excessive fresh-water use and thus promote a more eco-friendly attitude toward the local environment surrounding hydraulic fracking operations?

 Protesters at the Deleware Basin

Image URL:http://protectingourwaters.files.wordpress.com/2013/06/img_1748.jpg