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On September 6th, it was learned from Southwest Oil and Gas Field Company that the DE section of Pengtan 1 well has successfully completed the acid unblocking operation of the production well. The production oil pressure has increased by 33.4% compared to before the measures, and the daily gas production has increased by 42.2% compared to before the measures, restoring the original production capacity. The acidification production increase process measures have shown significant effects.

Pengtan 1 well is a high-risk exploration well located in the high part of the Penglai structure in the central Sichuan Basin. The drilling purpose is to explore the development and oil and gas potential of the reservoirs in the DE section of the Sinian system, the MK group of the Lower Permian, and the CX group of the Upper Permian in the Penglai structure in the central Sichuan Basin. After the production of this layer, the oil pressure decline will accelerate from 2023, indicating severe pollution in the near wellbore formation; Starting from July 2023, there have been multiple instances of significant increases and decreases in oil pressure and instantaneous quantities in production dynamics, exhibiting obvious characteristics of formation or wellbore blockage. Since 2024, the blockage situation of Pengtan 1 well has continued to worsen, with a minimum decrease of 32% in daily gas production.
Southwest Oil and Gas Field Company conducted a comprehensive analysis of production dynamics, production potential, wellbore conditions, etc., and preliminarily analyzed the presence of blockages in the wellbore and near wellbore areas. Based on the production dynamics of the well and the results of special well testing, the current type of blockage is mainly formation blockage, accompanied by the backflow of scale and blockage of the wellbore. In the face of this challenge, Southwest Oil and Gas Field Company analyzed the reservoir characteristics, actively drew on the construction experience of neighboring wells, and developed a targeted 80 cubic meter gel acid plugging resolution process plan. At the construction site, strict adherence to design parameters was observed, and there were clear signs of blockage relief during the construction process (pressure drop of 12 megapascals). After simulation calculations, the skin factor decreased to -4.