“Hydraulic Fracturing, Energy and the Environment”
Professor Lawrence P. Wackett
Distinguished McKnight University Professor
Department of Biochemistry; BioTechnology Institute
Recording Now Available:
Hydraulic fracturing, or fracking,
is a controversial process developed for releasing natural gas or petroleum
from tight shale formations. The process has opened up large, previously
unavailable sources of hydrocarbons for use as fuels and chemical feedstocks.
Hydraulic fracturing has been criticized as postponing a shift from
non-renewable fossil fuels to renewable biofuels; however, it has been
questioned whether biomass-derived liquid fuels could ever meet demand. The
energy needs of society for feeding more than 7.3 billion people will be
discussed in that context. Hydraulic fracturing is also impacting Minnesota and
Wisconsin because of increased mining of hard, spherical sand that is used as a
in the fracking process and water impacts of that process will be discussed.
Another criticism of hydraulic fracturing itself derives from its use and
contamination of water with chemicals and this has raised questions as to what
chemicals are present and how can they best be removed.
We have analyzed waters obtained from fracking in shale formations in North Dakota, Pennsylvania, and Texas, using methods similar to those employed in the Deepwater Horizon oil spill of 2010. The oil in the Gulf diminished over time due to weathering, submersion, and biodegradation. The latter was facilitated by the addition of surfactants to break the surface oil layer into micro-droplets that made the oil components more assessable to the indigenous hydrocarbon-degrading microorganisms in the Gulf waters.
In this context, biotechnology can play a role in mitigating against the negative impacts of hydraulic fracturing by removing contaminants and thus allow more recycling of water resources. Water discharge into municipal treatment systems is typically not allowed and this has led to the on-site treatment of water using evaporation, filtration, and ozonation processes. The former two concentrate wastes, which still require shipment and sequestration, typically to hazardous waste landfills. All of these methods are energy intensive. I will discuss bioremediation approaches that do not require an external energy source to operate and with the potential to degrade organic contaminants completely to carbon dioxide, therefore eliminating the requirement and expense of landfilling chemical concentrates. The goal is to clean the waters suitable for re-use in future hydraulic fracturing processes, significantly reducing overall water demand.
Tuesday, February 25