Sustainability in Shale Development EDSGN 100 Design Project, Fall 2016

Transcription

1 Sustainability in Shale Development EDSGN 100 Design Project, Fall 2016 Project Objective Keeping sustainability and stewardship of the environment in mind, as well as the need to remain a safe and profitable business, design an opportunity to improve upon common industry practices in shale development. Project Sponsor The project sponsor, Chevron, is the second largest oil and gas company headquartered in the United States. Chevron is a leading international energy company with more than 58,000 employees worldwide, and consistently ranks as one of the best energy companies to work for. Reliable and affordable energy powers virtually every element of the global economy, and has been behind the great advances in living standards over the past 150 years. Our industry touches the lives of millions of people in countless ways each day, providing the energy and jobs that enable us to improve our standards of living and quality of life. Project Background At the core of what we do at Chevron, we govern our actions by what we call The Chevron Way. The Chevron Way explains who we are, what we do, what we believe and what we plan to accomplish. It establishes a common understanding not only for those of us who work here, but for all who interact with us. Two of our key values are Ingenuity and Protecting People and the Environment. With that said, we are constantly seeking new opportunities and out of the ordinary solutions to improve upon common industry practices, but also realize we need to responsibly develop our resources for future generations to come. Within the Appalachian Basin, we are very fortunate to have an abundant supply of natural gas trapped in the shale formations beneath us. This resource has the potential to fuel our country for years to come and help make us energy independent. In order to realize this resource s potential, operators must perform a number of key operations, summarized below, in order to develop producing natural gas wells. Planning Phase The planning phase encompasses numerous activities, which can take several years to develop by a multifunctional team. These teams include engineers who are responsible for the planning and design of our well

2 pad sites, wells, and the supporting infrastructure and facilities. The planning phase is one of the most important phases in our projects as it is critical in creating value and the overall success of the project. Well Site Preparation (Execution Phase) Once the planning phase is complete, we move into the execution phase, which is kicked off by the well site preparation. The well site preparation consists of numerous activities, which include the construction of our well pad sites and preparation for the upcoming drilling and completion of our wells. The construction of our sites is critical in allowing adequate area for the safe execution of our upcoming work. With this said, larger pad sites allow for more area to safely work, but it comes at a cost as it requires us to disturb more of the land. So, this is where the planning phase starts reaping its benefits. As an engineer, one must evaluate the tradeoffs between the overall pad size (our footprint ) and safe/reliable operations. A significant portion of our footprint includes a temporary area for water storage. Historically, lined impoundments/pits have been a more economical way to store water on site; however, this method also increases the risk of impacting the surrounding groundwater (in the rare case of an incident). Therefore, with sustainability in mind and to protect the groundwater, many operators have made the move to tanks. With this change, operators are faced with the new challenge of increased water storage costs. Finally, in preparation for the upcoming drilling and completion of our wells, typically a portion of the well pad surface is lined with plastic liner which will act as containment beneath the drilling and completion activities. Due to heavy traffic and activities performed on top of this liner, it is not uncommon for operators to use a liner for a single pad and dispose of the liner after the project. With this said, there are definitely opportunities for operators to find other means of use for this liner once the project is complete. Drilling and Completing Wells (Execution Phase) Once the well site preparation is complete, the drilling rig mobilizes to site and prepares to drill the wells. With technology advancement in the industry, operators are now able to drill multiple horizontal wells from a single pad location (as opposed to older methods of drilling one vertical well from a pad). This horizontal drilling technology has been a major advancement in the industry and a key component in sustainability as we only have to construct one well pad to drill numerous horizontal wells. After the wells are drilled, it is time to complete the wells by a process called hydraulic fracturing (commonly referred to as fracking ). This process is needed to release the trapped natural gas in the shale formations below. In order to complete this activity, a large amount of water is required on site, and this is where water storage comes into play. Well Production & Operations (Operational Phase) Finally, after the wells are drilled and completed, it is time to start producing natural gas from the wells. The wells are then tied into production equipment and then into pipelines that transport the gas to our end users. The portion of the well site not being used will be reclaimed to the original contour of the land. The production equipment previously mentioned is situated nearby on the well pad, and is primarily responsible for separating the gas from the liquids. The produced water (brine) that is separated is commonly stored in tanks on site where it needs to be hauled off and treated or disposed of. 2

3 Project Instructions and Descriptions Project Instructions 1. Select one of projects described below, and identify an opportunity to design an improvement upon common industry practices 2. Examine this opportunity as a system, considering all inputs and outputs a. Consider any impacts the system may have to ongoing pad activities (i.e., simultaneous operations) b. Consider impacts to the surrounding communities 3. Design the opportunity and justify its economic viability and impact on sustainability (i.e., compare costs of new design to common practices, and compare it relative to common industry practices) 4. Ensure that the design requirements/considerations listed are incorporated into the design Project Descriptions 1. Water Storage a) Brief: In order to release the trapped oil and gas from the shale formation below, operators need to complete or hydraulically fracture the shale. This completion process requires a large amount of water (each well may require 5 million gallons of water and sites may have at least 10 wells per pad). The industry norm has been to construct lined water impoundments/pits (see photo below) that would house both fresh water and flow back (approximately 20% of the water injected will return to the surface after the completion activities). Keeping sustainability in mind, and the requirement to protect ground water, the industry has begun phasing out these impoundments/pits for more environmentally friendly storage methods (predominately above ground tanks). Although the tanks are a more reliable means of protecting the ground water, they are typically more costly and require a lot of area to house them. b) Project: Design an above ground tank system that has the capacity to store at least 3 million gallons of water on site. Considerations should be made for sustainability/environment, safety, cost, schedule/cycle time, footprint size, load bearing/settlement, ease of fill, corrosion, constructability, transportation, materials, and other potential uses for them during/after their life span. Lined water impoundment/pit 3

4 2. Waste Stream Drill Cuttings a) Brief: When we drill our wells, we produce approximately 10,000 cubic feet of drill cuttings (rock, water, and ~ 1% drilling fluid residue) per well. Drill cuttings are typically transported off site and disposed in landfills. b) Project: Come up with an innovative way to reuse/repurpose/recycle the drill cuttings. Considerations should be made for sustainability/environment, regulations, safety, cost, schedule/cycle time and transportation of the material. Typical drill cuttings 3. Waste Stream HDPE Well Pad Liner a) Brief: When we drill a well site, we line the surface of the pad with a 60 mil HDPE liner (or containment), which may be approximately Due to the heavy traffic that the liner may see, we typically use these liners only once (per pad) and need to cut it up on site and dispose. b) Project: Come up with an innovative way to reuse/repurpose/recycle the well pad liners. Considerations should be made for sustainability/environment, regulations, safety, cost, schedule/cycle time and transportation of the material. Typical installed well pad liner 4. Water Treatment Produced Water a) Brief: After a well starts producing gas, there is the need to regularly haul produced (brine) water off site. Typical production rate is 40 barrels/day (per well) with a concentration of 4

5 approximately 40,000 ppm TDS (total dissolved solids). Assume an average well pad may have 10 wells. b) Project: Come up with an innovative way to treat the water on site to produce marketable by products. Considerations should be made for sustainability/environment, regulations, safety, cost, schedule/cycle time and transportation of the material. Typical produced water storage tanks on site Key Deliverables Note: Your instructor will clarify her or his expectations for these deliverables and their respective due dates. Technical report containing the following elements o Team generated definition of sustainability, and what it means in shale development o Rationale for the opportunity identified o Description of alternative concepts and their evaluation o Assessment of the opportunity relative to the stated design considerations o Assessment of the opportunity relative to common industry practices Economic viability of the system Impact on sustainability Sustainability/environment Regulations and safety considerations Schedule/cycle time o CAD drawings detailing the design Systems diagram Complete list of design concepts Model of system Additional Resources EDSGN 100 Projects Website: Shale Gas Development Video: gas development andoperations Natural gas from Shale Video: Natural Gas from Shale Marcellus Center for Outreach and Research (MCOR): Sustainability Website: Center for Sustainable Shale Development: Chevron Website: 5