Calcium carbonate scale threats for deepwater developments have been predicted by calculating the saturation ratio (SR) and mass of calcium carbonate.

Assessing the threat scale may pose to an operation allows the design and implementation of robust barriers to reduce the risk. Scale threat assessment is particularly important in the early phase of a project when options for controlling the threat are being evaluated. It is important to correctly interpretate scale prediction result and its operational significance in terms of the threat likelihood and severity. Widely adopted guidelines, based on industry experience built up over many years from operations in US land and in the North Sea, have been used to aid interpretation. However, the relevance of these guidelines for deepwater projects has long been challenged.

The relationship between predicted SR and mass of calcium carbonate in deepwater is explored. Through case studies, it is apparent the current guidance is not stringent enough for deepwater. Additional guidance for deepwater operations is proposed.

This paper describes the deepwater operational experience that was used to justify a change in the critical SR and mass values in the scale threat assessment guidelines now adopted to assess the likelihood of scaling in deepwater fields.

You can access this article if you purchase or spend a download.