51312-01359-Numerical modeling of cathodic protecton applied to deep well casings

Available for download

Product Number: 51312-01359-SG

ISBN: 01359 2012 CP

Author: Yanxia Du

Publication Date: 2012

Member Price: $0.00

Non Member Price: $20.00

Price: $20.00

Qty:

ABSTRACTCathodic protection(CP) is one of the most effective methods of corrosion control for deep well casings. However it is difficult to measure the casing-to-soil potential and to evaluate the effectiveness of cathodic protection in the fields because the depth of wellcasings in vertical direction is up to 3000m. Numerical simulation can be used to aquire the casing-to-soil potential along the well casing as well as to determine the optimal parameters of CP systems according to the local environmental conditions. In this study the numerical simulation is used on well casings in an underground natural gas storage. While a computer software with three-dimensional boundary element analysis capability is used for evaluating cathodic protection performance of well casing. The effect of cement layer on surface electrochemical processes of the well casings is considered in the modeling progress. Furthermorevarious parameters of anodes bed such as the depth of anodes the length of anodes and the distance between anodes and well casings are also studied to obtain the best protection performance. In addition the comprehensive field measurements provide the detailed data about the soil that is considered as a multi-layered electrolyte with electric conductivity which varies from one layer to another one. The aim of the simulation is to predict the level of protection potential along the well casings and to study the interference between several well casings when they are protected by the same cathodic protection system. Keywords: Deep well casing Cathodic protection Numerical simulation Potential distribution