UNCONVENTIONAL GAS- DRILLING FOOTPRINT REDUCTION CHALLENGE

UNCONVENTIONAL GAS- FOOTPRINT REDUCTION CHALLENGE Team Members: AkhilPrabhakarSwapnil PalDheerajAgrawalShishirArya IIT ROORKEE

Environment Friendly Drillings (EFD’s)Prototype Small Footprint Drilling RigNOxAir Emissions StudiesDevelopment of Ultra-deep Drilling Simulator (prototype)Innovative Water Management Technology to Reduce Environmental Impacts of Produced Water

Prototype RigsMulti well Pad DrillingCoiled Tubing DrillingCentralized Fracturing

Multi well Pad DrillingMultiwell pad drilling minimizes the environmental footprint of drilling operations while improving efficiency, enabling simultaneous drilling and completion operations and reducing the number of well sites, vehicle traffic and land surface disturbances.Trinidad Drilling has 29 rigs operating in the Haynesville Shale, drilling as many as eight horizontal wells from a single pad.

Features:Ground level assembly without crane.Raise the mast and drill floor in one single shot.Raising system is built in to the substructure.Integrated mast sections and drill floor with drilling equipment.Mast stem sections are compact in size.Traveling block will be strung up to the crown block during rig move.Mast will include built-in guide rail.B.O.P. Handler & Transporter will keep the B.O.P. assembled during rig move. Source: Veristic Manufacturing

OpportunityConstraints can be blown up by combining various techniques.

One may think that this method has become a bit obsolete with the development of techniques like Coiled Tube Drilling.With countries like India almost finished with shale gas policy formulations, these techniques must be given importance.

Central FracturingWilliams Production RMT Company is using centralized pads to hydraulically fracture multiple tight gas sands wells on 10-acre spacing from a single central pad location in the Piceance Basin in Colorado. Working on as many as 22 wells simultaneously, the company has fractured as many as 140 wells from a centralized location, some as far as three miles away.

OpportunityProper choice of technique on the basis of ecosystem.

Coiled Tube DrillingBasic CT Equipment SubsystemsTYPICAL CTD

Opportunity:Increased BHA availability BHA cost reductionAdditional “fit for purpose” CTD equipments.

Micro Hole VSP ImagingThe opportunity microhole drilling offers for these deep unconventional-reservoir development projects lie in its potential for improved target imaging via low-cost seismic monitoring holes by use of new technologies and methodologies applied to vertical seismic profiling (VSP)Given better imaging of reservoir “sweet spots,” the industry will not have to drill conventional vertical holes from many closely spaced drilling locations to minimize exploration risk.Relatively high geologic risk Much lower engineering development riskIt should be used to shrink the smallest conventional hole size of 8.75 in. diameter to at least 3.5 in.Micro hole Imaging

UNCONVENTIONAL GAS- DRILLING FOOTPRINT REDUCTION CHALLENGE

LOW IMPACT RIGSThese rigs adapt to the environment with minimal disturbance.They are smaller, making them easier to moveThey can be more green on combination with pad drilling, they must have skid packages, which minimize surface disturbance and reduce overall well costs.They have rounded bottom tanks, having side valves that vacuum trucks can access to suck the fluid out more efficiently, reducing chances of spill.The round design also makes the cleaning process much easier and minimizes the fluid haul off. -Source: Pioneers 60 Series RigsLimitation:These rigs are smaller but are still capable of drilling to a total depth of 13,000 feet.

GREEN COMPLETIONS“Green” Completions can be dubbed as capturing methane during drilling completion and production (mostly in the flow back stream following hydraulic fracturing).For this company must employ its midstream assets to lay a pipeline and flow wells back through a separator, thus removing the sand and water and capturing the remaining gas in a pipeline, rather than venting or flaring the gas.Recently, Devon has been able to quantify a reduction of 13 billion cubic feet of emissions in the Barnett Shale area of North Texas by using green completions.

NOxAir Emissions Studies From well drilling; to fracking; to gas extraction, processing, and transmission, sources of air pollution emissions exist at every step in the process of converting unconventional gas into a marketable product. Air pollution sources from natural gas operations include: • vehicle emissions from construction equipment and diesel trucks hauling workers, drilling equipment, frack water, and waste water; Solved by Central Fracturing, Pad Drilling • diesel engines used to power drilling rigs and fracking pumps; Using Alternative Sources • large natural gas-fired stationary engines used to compress natural gas for pipeline transport; • emissions of raw natural gas to the atmosphere during well completion and from leaking pipes, valves, storage tanks, and processing equipment; Solved by CTD to some extent • volatilization from open wastewater pits. Solved by water management techniques

Development of Ultra-deep Drilling Simulator

Innovative Water Management TechniquesObjectives under this techniques:Evaluation of promising commercially-available technologies for water reuse; Development of novel coatings to improve performance and cost of ultra filtration, nano filtration and reverse osmosis treatment technologies in the demineralization of flow back waters; Development of electro dialysis reversal for low-cost produced water and flow back water demineralization; andIdentification and evaluation of alternate sources of water that may be useful as replacements for groundwater or surface waters that serve as community water supplies.

Oil shale produced waters are typically derived from retorting, mine drainage, and leachate from spent oil shale because of the methods used for extracting hydrocarbons from shale.Waters generated from oil shale can contain many of the same constituents of concern (e.g. metals, arsenic, selenium, organics, and chlorides) present in other produced waters.Simple treatment options include: ion exchange, reverse osmosis, electro dialysis reversal, mechanical evaporation. Limitation: High CostCost could be retrieved from improved efficiencies

Solution: Constructed Wetland Systems Must include centralized facilities (pipe or haul to the location and treat) or decentralized facilities designed for a single well or for a few nearby wells. Even portable or “package” constructed wetland treatment systems can be designed to be pulled to a site by truck and capable of immediately treating water after set up. These “ready-to-go” systems could be very useful during fracture stimulation or high initial water production from unconventional gas wells.

The components of a cell (hydrosoil, vegetation, and hydroperiod, in effect the residence time) are selected to produce conditions that promote specific biogeochemical treatment processes.Hydrosoil (planting medium) contains sand, clay, and organic matter with proportions dependent upon desired conditions. Examples of vegetation include Schoenoplectuscalifornicusor bulrush when reducing conditions are needed and Typhalatifolia (cattail) to promote oxidizing conditions. Hydroperiod is managed initially for rapid plant growth and then to sustain treatment performance. The length of wetland cells in typical full-scale constructed wetlands ranges from a few m to over 100 m.

Impact of Constructed WetlandsReduces Environmental Riskshave the potential to be used for a variety of purposes, such as irrigation, livestock watering, cooling-tower water, municipal water use, domestic use, discharge to receiving aquatic systems for other use downstream, and support of critical aquatic life and wildlife. This can allow continued operation of existing wells in mature fields with high water cuts and also lead to increased drilling and production, increasing the contribution of domestic energy resources to our national energy supply.

Combination of all aspects of EFD’s-EFD ScorecardA scorecard must be developed to measure the tradeoffs associated with implementing low impact drilling technology in environmentally sensitive areas.The scorecard must assess drilling operations and technologies with respect to air, site, water, waste management, biodiversity and societal issues.The scorecard must address issues likegetting materials to and from the rig site (site access)reducing the rig site areausing alternative drilling rig power management systemsadopting waste management at the rig site.

Eco-Centre Waste Management Facility This waste processing center provides an unparalleled level of environmental compliance from the rig to final disposal which includes remote monitoring capabilities, allowing companies online access to track their waste streams and ensure environmental reporting compliance.The 30,000-square-foot Eco-Centre facility can process in excess of 30,000 tonnes (33,000 tons) of drill cuttings and 14,000 cubic meters (3.7 million gallons) of liquid waste, or slops, annually.The facility segregates each company’s drill cuttings, creating a transparent and fully auditable trail.This facility provides E&P companies 24/7 visibility of their waste streams throughout the process.

Eco-Centre facility aims to recycle and reuse the generated waste streams to reduce the overall carbon footprint of the facility and the operators it serves.The “cleaned” solid materials are used in place of quarried aggregates to cap local landfill sites. The recovered oil is reused to fuel the processing mill at the Eco-Centre while recovered water is used to cool and rehydrate the recovered solids. To minimize use of local water resources, rainwater is captured and used for a variety of purposes, including fire suppression.

Efficiencies of Traditional WellsStages of Efficiencies for an E&P firmAs these stages are cumulated we get more benefits

Efficiencies in drilling can be improved by using the techniques discussed in EFD’s.Companies are now contracting for “fit for purpose” rigs and equipments to reduce drilling days.Formation of Cross functional teams to maximize the production from wells operating in the basin. By investing $15 million in installing new pumping units and compressors, changing tubing sizes and performing well work over, production from these unconventional wells can be increased by 20%. Source: William Cos.

What are “fit for purpose” rigs and equipments?

Efficiencies in Water Treatment and Disposal can be increased using Electro dialysis to separate desalted water from concentrated saline solution other than reverse osmosis, etc.Recently it has been have shown that CBM produced water could be treated for $0.15/bbl

Efforts to reduce F&D costs must be initiated. Also focus must be put on reducing drilling, simulation costs along with increased well recoveries.This will help in increasing efficiencies in finding and Development Costs.

CONCLUSIONSIn this presentation, we tried to follow a balanced strategy which addresses almost all issues that appeared significant to us.The techniques suggested can be combined together depending on geographical location and economies of various rigs.Basically, we have prioritized increase in efficiency of each operation keeping in mind the environmental implication.

REFERENCESArticle: “Advances in Unconventional gas”Baker Hughes Waste Management TechniquePaper: Economics of Unconventional GasE&P Focus News (Winter 2009)

UNCONVENTIONAL GAS- DRILLING FOOTPRINT REDUCTION CHALLENGE

More Related Content

What's hot (20)

Similar to UNCONVENTIONAL GAS- DRILLING FOOTPRINT REDUCTION CHALLENGE (20)

More from Akhil Prabhakar (16)

Recently uploaded (20)

UNCONVENTIONAL GAS- DRILLING FOOTPRINT REDUCTION CHALLENGE