Collins Ian, World Oil, May 2003, Vol. 224, Issue 5
In this article Collins discusses the issues of managing risks of inorganic scales in deepwater operations. One of the most common forms of inorganic scales are the build-up of calcium carbonate and barium sulfate. These compounds negatively affect drilling equipment, and it is extremely expensive to mitigate against their affects.
According to Collins, British Petroleum developed a process within microsoft excel, based on decision tree analysis to assess the risk of scale development and the potential damage it could cause to a deepwater operation. Two parameters are quantified in assessing scale risk, first the probability of scale formation and second the consequences. The probability of scale damage is quantified with a number between zero to one. Zero meaning no chance of happening and one meaning its certain to happen. After a probability and consequence are paired, then a value is assigned to the risk it represents.
Once the level of risk is established then a decision tree is presented and the branches are given a cost benefit analysis based on the risk they grew out of.