Utilization of Absorbent Hydrophilic Polymer to Dry Water Based Drill Cuttings

Abstract Oil and Gas drilling rigs use waste pits on location for capturing drill cuttings and all liquid waste discharge. Closed loop drilling practices have been successfully demonstrated to greatly reduce the volume of liquid waste and separate from the water-based cuttings (WBC) using mechanical dryers’ equipment. After extensive lab and field evaluation an Absorbent Hydrophilic Polymer (AHP) was used to effectively dry WBC using a method that is more economical than mechanical dryers. Wide lab testing on multiple WBC were performed In-house in order to verify the absorbent properties of the hydrophilic polymer. WBC samples for different wells were collected and analyzed at the lab before and after the AHP treatment. Lab results showed absorption of the liquid phase with minimal AHP dose concentrations. Once the AHP performance was verified at the lab, we moved to the field evaluation. A candidate well was identified and 35 cubic meters of WBC were collected and treated. Key performance indicators (KPI’s) were established as part of the evaluation criteria to assess the AHP performance. A telehandler and bucket mixer were used on the field trial to estimate mixing time, assess the consistency of stabilized cuttings and determine the desired concentration of the AHP. The volume of cuttings treated (35 cubic meters) required an average AHP concentration of 0.62% (397.6 kg) and an average mixing time of 4 minutes. Additionally, an economical comparison between employing drying shakers and using AHP per well was done, taking into consideration that with drying shakers, all equipment and personnel costs are charged every day from rig up until rig down. With AHP utilization it is charged per used consumption meaning that the less cuttings come to surface, the less AHP is used and only while drilling. Thus, the cost reduces for a product that is dry, stackable and easily managed. In summary, after evaluating the collected data at the field and comparing with the established KPI’s for the field evaluation, it was concluded that all KPI’s were accomplished: field trial was conducted in a safe and controlled matter, usage was tracked and reported, WBC were stabilized and stackable after the treatment, no more than 20 kg per cubic meter were used and we observed full absorption of WBC’s liquid phase. This paper describes the utilization of Absorbent Hydrophilic Polymer to dry water-based cuttings and the excellent performance observed of this technology, contributing in the optimization of the waste management and minimization quest.