Water Blasting for Scale Removal in the Rangely Weber Sand Unit

Abstract

Abstract Barium sulfate scale deposition is a serious operational problem in the Rangely Weber Sand Unit (RWSU), often resulting in lost oil production. The historical method in the RWSU to restore production was to mechanically scrape the scale from the wellbore and then hydraulically break through any scale remaining in and around perforations. An alternative mechanical method of scale removal was recently used on a trial basis in the RWSU. Water blasting was used which directs high pressure jets of water with polymer additive at the perforations and casing wall. Water blasting was used on four wells and the results indicate that while water blasting does remove some scale, it is not an attractive option for stimulating production where barium sulfate scale has caused reduced production.