Research Institute for Oilfield Chemistry (Russia)

Sand production restricts the safe extraction of hydrates, making efficient sand control technology essential for the industrialization of hydrate development. Microbial-induced carbonate precipitation (MICP) has emerged as a promising technique for reservoir reinforcement, offering both formation stabilization and effective sand control. In this study, the sand control efficiency and underlying mechanisms of MICP-reinforced hydrate deposits are explored. Meanwhile, the sensitivity analysis of factors that influence the sand control effect and the impact of reinforcement on permeability are examined. The experimental results demonstrate that the amount of sand production in the MICP-reinforced deposits can be reduced by more than 96%, as the calcium carbonate bridge effectively enhances the resistance of the sand particles against fluid erosion. Moreover, the reinforcement allows sand particles to aggregate, enhancing the stability of both the sand bridge and the clogging structure. The critical operational factors affecting sand control efficiency include treatment duration, reinforcement range, and grouting flow rate, which should be greater than 3 days, at least 3 times the thickness of the gravel layer, and less than 4 mL/min under investigation, respectively. Although there is a certain reduction in porosity and permeability, any loss in production potential during depressurization can be compensated for by optimizing the reinforcement range and increasing the production pressure differential.