Understanding Ceramic Proppants: Are They All Created Equal?

Abstract

Abstract Introduced in the 1970's, ceramic proppants have provided the industry with higher conductivity alternatives to naturally occurring frac sand, and are used to increase well productivity in a wide range of reservoir conditions. Initially dominated by a handful of ceramic proppant manufacturers, the increased recognition of the need for highly conductive fractures has led to a tremendous growth in the industry, with nearly 100 ceramic proppant plants in operation today [Kim 2012]. The oil and gas industry used more than 65 billion pounds of proppant in 2011, and the rapid growth of the ceramic industry often could not keep pace with the surging global demand. This explosive growth has led to significant variations in ceramic proppant quality and sustained conductivity, which affects production benefits. Although the industry has historically considered ceramic proppants to be interchangeable, they represent a wide range of different materials whose properties are highly dependent upon their composition and manufacturing technology. This paper will examine the performance of different types of ceramic, including lightweight, intermediate density and high density proppants, and some of the new materials that don't necessarily fit neatly into these categories. It will also describe the major manufacturing techniques used in the industry, and illustrate the differences that key steps in the industrial process have in the quality and conductivity of the final product. Microphotographs and laboratory testing will be supplemented with modeling forecasts to show the productivity expected from specific ceramic proppants at realistic conditions. Finally, field studies will be presented which corroborate the predictions that proppant quality significantly affects well productivity and proppants within the same generic categorization do not provide identical productivity. This paper will serve as an excellent resource to completion and fracture design engineers as they navigate their way to choosing the optimal proppant for specific well parameters and economic conditions. It will be clear that proppants should not be considered an interchangeable commodity, and that well performance will be dependent on the quality and characteristics of the specific proppants selected.