Self-cementing chemical leak-stopping agent for drilling and its prepn process

Abstract

The present invention relates to self-cementing chemical leak-stopping agent for drilling well and its preparation process. The self-cementing chemical leak-stopping agent is prepared through mixing bauxite, lime stone and gypsum in the weight proportion of 20-40 to 30-60 to 10-30; baking the mixture at 1000-1500 deg.c to obtain intermediate product; grinding the intermediate product; and mixing the intermediate product, gypsum and lime stone and quartz sand in the weight proportion of 60-90 to 5-15 to 5-20 to 5-15 to obtain the chemical leak-stopping agent. The present invention has the advantages of rich material, low cost, simple preparation process, wide applicable temperature range, fast leak-stopping speed, high pressure bearing capacity and being suitable for stopping leak in oil reservoir.

Description

Technical field: [0001] The invention belongs to a plugging agent for petroleum drilling. technical background: [0002] Lost circulation is one of the most serious complex situations in the oil drilling process. The occurrence of lost circulation will bring inconvenience and loss to the drilling project, consume drilling time, lose drilling fluid and plugging materials, and cause pipe sticking, blowout, and well collapse. A series of complex situations, such as drilling, even lead to the scrapping of the wellbore, and also cause damage to the oil layer, resulting in major economic losses. [0003] For serious leaks caused by fractures or caves, leakage is mainly plugged by chemical plugging agents. There are two types of chemical plugging agents, cement and resin, with cement as the main one. When cement is used as a plugging agent, it must first be mixed with water to make cement slurry. There are many factors affecting the performance of cement slurry. As a plugging slu...

AI Technical Summary

Problems solved by technology

When cement is used as a plugging agent, it must first be mixed with water to make cement slurry. There are many factors affecting the performance of cement slurry. As a plugging slurry, it has the following disadvantages: (1) It is not easy to stay in the leakage channel, and it is often caused by leakage into the deep formation. And lead to plugging failure; (2) After entering the leaking zone, the cement slurry is mixed with formation water and diluted, resulting in a longer solidification time of the cement slurry, or even not solidifying, resulting in plugging failure; (3) Due to the solidification characteristics of the cement slurry, its The injection time must be strictly controlled, and the construction is difficult

Resin is used as a plugging agent, and its disadvantages are: (1) It can only be cured within a specific temperature range, and the operating temperature range is narrow; (2) Compared with other plugging agents, the cost of resin is high; (3) The construction is difficult