Hydraulic Fracturing Best Management Practices Environmentally Friendly Drilling
Hydraulic Fracturing Best Management Practices Environmentally Friendly Drilling Program John Michael Fernandez Matthew Gunter
Objectives of Presentation • Introduce and describe hydraulic fracturing • Present environmental concerns • Discuss best management practices
US Shale Plays
Major Shale Plays with Hydraulic Fracturing • Bakken o North Dakota, Montana, Canada o Oil • Barnett o Texas (DFW Area) o Natural Gas • Eagle Ford o South Texas o Oil and Natural Gas • Haynesville o Texas, Louisiana o Natural Gas • Marcellus o Pennsylvania, Ohio, New York, West Virginia o Natural Gas • Woodford o Oklahoma o Oil and Natural Gas
What is Hydraulic Fracturing? • Hydraulic fracturing is a process used to stimulate wells in tight, shale reservoirs. • Uses water, sand chemicals to extend, prop open fractures to allow for the flow of oil and natural gas.
Hydraulic Fracturing Process • Drill the well o o Some only vertical Some have horizontal lateral o o Pressure zones Ground Water Areas o Begins fracture process in rock formation o High pressured fluid extend fractures • Case and Cement possible hazard areas • Perforate casing and cementing with Perforating Gun • Pump fracturing fluid down hole • Production
Casing and Cementing • Casing and cementing a wellbore is used to: o Protect groundwater from contamination o Keep integrity of well-bore • Casing is steel pipe that is designed to handle: o over- or under-pressured zones o high tensile stresses down hole and • Casing is cemented in place to safely deliver hydrocarbons to the surface
Perforating the Formation • Perforated using a “perf gun” o Perforating fracture: o Casing o Cementing o Formation guns use explosive charges to
Fracturing Fluid • 98 -99. 5% Water and Sand • The other 0. 5 -2%: o Additives that enhance fracturing o Many additives are used to protect casing, cementing, and well integrity • 3 -7 million gallons of fluid used in typical horizontal well
Proppant • Sand pumped down hole is known as proppant o Keeps fractures “propped” open o o Untreated sand Resin-coated Sand o Ceramic • Comes in three major forms § Coated for strength in harsh conditions § Artificial Proppant, very strong at high pressures § Said to be in shortage, more using resin-coated sand • Selected based on strength needed and size
Chemical Additives • Common Additives include: o Acids, Biocides, Gelling Agents, p. H Adjusting Agents, Corrosion Inhibitors, Iron Control, Clay Stabilizer, Acid Inhibitor o Other additives could be used depending on well characteristics o Additives considered harmful are often found in household items
Hydraulic Fracturing Animation
Environmental Concerns • Chemical concerns o Pumping chemicals near water table o Failure in pits and liners could leak chemicals • High water usage • Air Emissions from truck use • Surface Area used
EPA Study • Looking into groundwater protection • Major areas of study include: o Water acquisition o Chemical Mixing o Well Injection o Flowback and Produced Water o Wastewater treatment/disposal
Water Table Safety – Fracture Facts • Fractures are necessary for hydrocarbons to flow from the tight shale formations • Fractures are typically thousands of feet below water table • They extend only hundreds of feet at most in any given direction
Hydraulic Fracturing BMPs • “Green Frac” Program Idea o Chesapeake Energy o Restimulation via fracturing again o Chief Oil and Gas one of many users o Drills multiple wells from same pad site o Fracturing multiple wells from central pad • Refracturing wells • Closed-loop Fracturing System • Pad Drilling • Centralized Fracturing
Green Frac Program • Program instituted by Chesapeake Energy o October 2009 • Researching additives to: o Find which are unnecessary which are necessary, but harmful more environmentally friendly replacements for harmful additives • Specific findings are proprietary information
Refracturing Wells • Used to restimulate wells with production slowed • Reduces surface area taken by taking away need for new well for oil and gas • 85% of success found in 15% of total wells drilled o Not universally successful • When successful, greatly increases production
Closed Loop Fracturing System • Rather than using water only once and putting in large pits, the frac fluid is circulated and stored in large steel tanks • Solids are removed from water using mechanical and chemical methods • Compared to older methods, CLF is o Environmentally friendly o Economically efficient
Environmentally Friendly CLF • Takes away use of pits and liners Pits and liners have been known to burst, releasing chemicals onto surface o Stores in large, sturdy steel tanks o • Uses much less water o o Water is reused throughout fracturing process Reduces water usage by as much as 80% • Reduces truck traffic Truck loads have been observed to reduce by up to 75% o Reduces air emissions and traffic congestion o
Economically Efficient • Water usage is reduced • Truck mileage is also reduced • Companies who have drilled similar wells using CLF have saved about $10, 000 in overall expenses compared to conventional drilling
Pad Drilling • Drills multiple wells from single pad site • Allows for centralized fracturing o Fracturing from single location for multiple wells • Reduces acreage necessary for wells • Reduces truck traffic for making pad site • Enhances closed loop systems
Centralized Fracturing • Fracing multiple wells on a site from a single, central pad o o Fraced up to 140 wells from single site Fraced up to 3 miles away • Significantly reduces truck traffic and time expended Truck traffic was reduced by up to 30% for a single well, up to 90% for the site as a whole o Time was reduced by up to 80% to drill, complete the well o • When used with closed loop and pad drilling, saves even more truck traffic and water used
Past, Present, and Future Best Management Practices
Conclusion • Hydraulic fracturing is the future of the energy industry • There are environmental risks involved • BMPs could be the answer to put unease at rest • When used in combination, BMPs can be even more effective. • Questions?
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