Terralog Technologies Inc provides a Cuttings Re-Injection (CRI) Project Management Service that includes technical support, data management & project management services for injection of drilling wastes (drill cuttings, waste fluids, muds, etc).
Cuttings Re-Injection (CRI) involves injection of waste from drilling operations (slop and drill cuttings) into a suitable deep geologic formation.
Injection will typically require pressures that result in hydraulic fracturing in the formation. This process is considered an environmental friendly and cost-effective disposal method during drilling operations, especially with offshore E&P operations.
Zero Discharge-Exploration and Production (ZD-E&P) refers to oilfield upstream operations that generate various waste streams, and managing these waste streams so there is no (or minimal) negative interaction with the biosphere (soil, surface water, ground water, and air quality).
TTI’s CRI services include:
Technical-engineering support (exclusive of platform pumping services) in the CRI planning stage:
- Geological assessment
- Equipment assessment
- Well design
- Injection strategy design
- CRI Best Practices
Project regulatory support:
- Liaison with regulatory agencies for project permitting
- Detailed area-of-review for project permitting
- Preparation of applications for regulatory approvals
- Regulatory liaison and project documentation
Daily technical-engineering support, process monitoring and reporting during active CRI operations:
- Design and implementation of optimum injection strategies
- Analysis of injection data to optimize the injection strategy
- Maintain formation injectivity
- Ensure material containment in the disposal formation
- Ensure CRI well performance and integrity
- Maximize formation storage capacity
Data management services for CRI disposal operations, using TTI’s specialized database applications and data management processes.
Project documentation (daily, weekly ops reporting) and regularly scheduled project meetings with the Drilling Rig Groups.
CRI Piggyback Concept
The CRI Piggyback Concept offers proven and significant advantages for deep well disposal of drilling wastes and related waste streams during onshore or offshore operations.
The key element of the Piggyback Concept is integrating the CRI operations with the existing rig equipment systems. Existing topside equipment is used and connected to a dedicated disposal well.
The CRI operations, drilling and cementing operations are synchronized to use idle cementing equipment and employ available cementing crews during CRI. Typically only a small slurrification unit is needed as additional equipment.
- achievable ‘zero discharge’ drilling operations…economically;
- fast implementation with minimal rig modifications;
- low CAPEX & low implementation cost
- disposal of large waste volumes (1000++ m3/month/well);
- use of modified existing wells, or dedicated water disposal wells;
- continuous injection cycles – synchronized with drilling & cementing operations;
- disposal of multiple waste streams (drilling wastes, slop, waste water);
- improved well drilling performance and drilling costs;
- reduced requirement of dedicated site crew;
- proven and successful in North Sea offshore drilling operations.
CRI Piggyback eliminates the need for:
- dedicated and complex topside equipment systems;
- high CAPEX & implementation costs of a stand-alone CRI operation;
- large dedicated manpower requirements in the field; only 1 dedicated engineer is required, working with existing cementing crews with the piggyback approach;
- ‘skip and ship’ operations from offshore platforms/rigs to onshore disposal sites.
Bergen – Statoil
Terralog provided CRI services to Statoil from 2007 to 2016.
This offshore project was based on a dedicated injection well for drilling waste disposal in the North Sea. Two different techniques of CRI injection operation have evolved:
- the ‘direct sand’ injection;
- ‘bottom shale’ injection approach.
Volumes of waste (slurry or slop material) using either technique varies on a daily basis and is dependent on the drilling operations needs. The CRI well is completed in a target zone (a deep formation characterized as a thick, permeable, unconsolidated sand.
Proper implementation of ‘Best Practices’ for this CRI operation was used to assess/address/resolve injection issues in a timely manner. Accordingly, the technical support work used on this project was able to meet the operational-drilling and zero discharge objectives of the client by ensuring concurrent, controlled, and reliable CRI operations.
Manifa – Saudi Aramco
Deep well disposal of slurried drilling waste using a modified CRI process has been implemented at the Saudi Aramco Manifa Oilfield. Injection of drilling waste at Manifa began in 2012, and has continued with up to eleven disposal wells being active during drilling operations.
To-date (June 2016), over 294,379 bbls of drilling waste streams have been injected.
The modified CRI operations utilize a cyclic ‘slurry fracture injection’ process at high rates with direct-sand injection via dedicated disposal wells.
Extensive process monitoring/analyses is used during CRI operations to ensure process control.
The waste streams include drill cuttings, oil based drilling fluids, water based drilling fluids and brine.
Deep well disposal provides a secure operation achieving ‘zero discharge’ by injecting cuttings and associated fluids.
The Khafji disposal formation was chosen for ‘slurry’ waste injection at Manifa field since it met or exceeded the desired criteria for permeability, porosity, depth and other properties.
Injection takes place on drilling rigs and into dedicated disposal wells. Hydraulic fracturing is necessary to inject the slurry containing drilling wastes.
As injection goes on, slurry design, injection strategy and dynamic formation geomechanics/fluid flow response will affect to the performance of the disposal formation. The use of modified CRI operations, using a cyclic, high rate slurry fracture injection process, is essential to ensure process control, maximize the formation storage capacity for these disposal wells/formations; and to ensure that the zero discharge operational-drilling objectives of the Manifa Drilling Team are met.