Polyanionic Cellulose requires controlling fluid loss mainly for the following reasons:
I. Ensuring drilling safety During the drilling process, if the fluid loss is too large, a large amount of drilling fluid will enter the formation, which may lead to the following problems:
1. Reducing wellbore stability: A large amount of drilling fluid entering the formation will change the pressure balance of the formation and may cause phenomena such as wellbore collapse and sloughing, seriously threatening drilling safety.
2. Affecting formation evaluation: Excessive fluid loss of drilling fluid will contaminate the formation and affect the accurate evaluation of formation properties, such as the determination of parameters such as porosity and permeability.
II. Improving drilling efficiency
1. Maintaining stable drilling fluid performance: Appropriate fluid loss can keep the drilling fluid in good performance in the well, and properties such as viscosity and density will not change greatly due to excessive fluid loss, thus ensuring the smooth progress of drilling operations.
2. Reducing drilling fluid consumption: Controlling fluid loss can reduce the loss of drilling fluid and lower drilling costs. At the same time, it also reduces the workload of frequently replenishing drilling fluid and improves drilling efficiency.
III. Protecting reservoirs
When drilling through oil and gas reservoirs, excessive fluid loss will cause damage to the reservoir and reduce the permeability and productivity of the reservoir.
By controlling the fluid loss of polyanionic cellulose, damage to the reservoir can be reduced and good conditions can be created for subsequent oil and gas exploitation.
In summary, requiring fluid loss for polyanionic cellulose is to ensure drilling safety, improve drilling efficiency and protect reservoirs.
