Implementation of Drilling Waste Pneumatic Transfer Process for Zero Discharge Deepwater Well in Mexico

SummaryBHP BILLITON is the first IOC to drill a Deepwater well in the Mexican Perdido region of the Gulf of Mexico basin. One of the main challenges for a drilling operation is to comply with Mexico's Zero Discharge policy where the process of logistics and drill cuttings waste handling/transportation is a key part for the pre-drill planning to ensure that ongoing drilling operations are maximized. Any delays in chain of events can result in bottlenecking the drilling performance, thus increasing drilling cost and time for the project. This part of the project requires a dedicated integrated strategy to deliver the drill cuttings from the rig, to the workboat, and transported back to the shore base facility even in rough weather conditions.BHP BILLITON collaborating with Schlumberger deployed an alternative waste management process that replaced the “skip and ship” or conventional cutting boxes method. The conventional method uses numerous cutting boxes and many crane lifts to move waste from the rig to the workboat, but presents a higher HSE risk and potential bottlenecks to drilling performance. The new solution, CleanCut technology pneumatically transports cuttings from the shale shakers to specially designed storage unit (ISO-Pumps) located on the rig that also serve as buffer storage in the event of bad weather. The cuttings can then be pumped from the ISO units on the rig to waiting ISO units on the boat or other storage containers on the supply vessel. The transportation of the cuttings from the shale shakers on the rig to the shore base is achieved with minimal or zero crane lifts thus minimizing harm to personnel.The CleanCut system achieves a safer work condition and ensures that drilling operations can continue unimpaired to achieve the drilling performance. The successful application on the BHP BILLITON Trion 2-DEL well enabled the project to reach Rate-of-penetration (ROP) approximately 58% higher than the average Deepwater well drilled in similar zero discharge condition (*referencing Schlumberger Database). A total of 1108 tons of cuttings were transported safely during the first well operation.