Wellbore Calcite Deposition: A Case Study at Domo San Pedro

Abstract

The Domo San Pedro field began commercial operation in 2015 with the commissioning of two back pressure units. In March of 2016, a new, condensing unit was commissioned, and by December 2016 it was operating with 4 production wells. In October 2016, well A reached its maximum production and began a steady decline of 0.023 tph/day. Mineral speciation modelling suggested this well was supersaturated with respect to calcite. A mechanical workover was executed in August 2018 but well head pressure and total mass flow data showed the workover was not successful. The issues were identified as calcite and silica scaling in the wellbore and formation. A chemical intervention and stimulation that did not involve the use of risky Hydrofluoric acid happened in July 2019. This paper presents the case history of this well, the information that was studied, the results of the chemical speciation modelling, the design of the chemical intervention, and the preliminary results.