Wellbore Cleaning Prior to Completion Utilizing Surfactant Combination
Grant
Overview
Affiliation
View All
Overview
abstract
Efficient oil and gas drilling largely depends on how efficient hole cleaning is. If the hole is not properly cleaned, that means rock fragments produced by the drilling are not removed from the wellbore, further drilling will be hindered. Issues caused by improper or insufficient hole cleaning ranges from stuck pipe, lost circulation, high torque and drag and poor cement jobs. These issues if not addressed appropriately will not just be expensive operationally, but will also result in a more catastrophic effects to the environment and as well as ultimately loss of human lives. Hole cleaning as defined is the ability of a drilling fluid to transport and suspend drilled cuttings. Effective hole cleaning is dependent on the properties of the fluids to perform the cleaning. Therefore, it is very important to determine the properties of the drilling fluid in order to transport cuttings from the drill bit up to the annulus and to the surface. In general, hole cleaning is easier for vertical wells, and it is more challenging for highly deviated and horizontal wells. The hole cleaning does not stop at the drilling stage but it also needs to be done very meticulously before the completions operations, which involves extensive circulation of seawater or completion brines. The addition of chemicals (either surfactants or polymers) has been shown to improve wellbore cleanup and decrease the volume of fluid needed to complete this operation. Flocculation (with polymers) and coagulation (with surfactants) aggregate particulates in the wellbore, thereby increasing fluid drag and sweeping efficiency of the fluid circulated in the wellbore. The cleaning process depends on the properties of the surfactants adsorbing on the solids. Modifying the physico-chemical characteristics of these surfactants mixtures can improve the wellbore cleanup. If wellbore cleanup is not done properly prior to production, it may lead to production loss and demands expensive repercussion. The purpose of this project to investigate the best combination of surfactants and caustic soda on seawater and drill water systems. The students will perform a detailed literature review to become familiar with principles involved, and design and conduct the actual experimental procedures. Positive outcome of the project will be helpful to the oil and gas industry in ensuring a safe operation, preventing future expensive maintenance and workover costs and would help in improving production capability and revenue.
