Rate of penetration management is a matter of importance in drilling operations and it has been used in some research studies. Although conventional approaches for rate of penetration management are mainly focused on analytical and semi-analytical models, several correlations have also been developed for this purpose. The history of rate of penetration management studies extends back more than half a century and ever since, research interest in this concept has never declined, making it a focus of industry and academic studies. In this article, some of these studies are reviewed to achieve a better understanding of rate of penetration management concept, its financial benefits and also its research capacities. This review reveals the most common rate of penetration management methods which applied analytical, semi-analytical and empirical correlations in different fields around the world. In other words, the main purpose of this study is to evaluate the research studies in which different models and correlations have been used as the main approach for rate of penetration management. Based on the results of this review, the best models for performing rate of penetration management studies and the best objective functions for optimization algorithms are introduced.

Fluid loss during cementing operation in depleted reservoirs or deep wells of reservoirs with low breakdown pressure is a major concern for maintaining well integrity. This issue is usually handled by reducing the weight of cement slurry. Although various slurry formulations were proposed during the last decade, the cost and availability of required additives is still a concern, especially when the oil price is low. The objective of this study is to make lightweight cement slurry with a density of 105 lb/ft ${}^3$, using the combination of natural pozzolan and API class G cement. This study proposes a new lightweight cement formulation based on the optimum amount of a natural pozzolan and other additives. Based on the results of 24-hour compressive strength tests and free water volume, an optimum 30% of cement powder was replaced with pozzolan. Addition of more pozzolan into the slurry reduces its pumping even at room temperature. The bottom-hole condition was simulated by increasing the temperature to 150 ${}^{\circ }$F, and chemical additives were used to maintain the rheological properties of this slurry. Fluid loss control agent, dispersant and retarder were used at optimum values 0.5, 0.08 and 0.05 (%bwoc), respectively. The compressive strength of the cement rock was monitored at 3, 7 and 30 days, reaching to 3, 528 lb/in ${}^2$ after 30 days.