What’s the Best Friction Reducer? You Need To Figure It Out Yourself

Abstract

Friction reducers are expected to play critical roles in fracturing, some better than others. Shale producers are belatedly realizing that there are many variables that can alter the performance of these chemicals used to reduce the power needed to hydraulically fracture a reservoir, and in higher doses, to thicken fluid, making it possible to deliver proppant more efficiently. There are wells that can justify paying more for a friction reducer formulated to stand up to difficult chemical challenges, and others that cannot. But there is no guide that describes how these key additives perform. Those who do evaluations will realize that a lot of details about friction reducers are proprietary and no industry standard provides guidance about the information needed to thoroughly assess their compatibility with reservoir conditions. “There hasn’t been a really good method to quantitatively evaluate friction reducers and what they do,” said Paul Carman, the completion fluid advisor for ConocoPhillips, who has not figured out what that method might be. Recently, Occidental Petroleum took a stab at answering the question with a paper discussing its evaluation of friction-reducer performance. It’s not a short answer. The paper delivered at the Unconventional Resources Technology Conference (URTeC) does not offer names of the products tested, how many were tested at any stage of the process, or details that might identify top performers (URTeC 5249). Those who dig deeper and ask fracturing experts will learn that the best friction reducer will depend on the job. And money, time, and research are required to gather the data needed for informed decision making. When Occidental began working on a system to evaluate friction reducers, they found little had been written on how to do it, said Nancy Zakhour, Occidental’s well design lead, a coauthor of the paper. There was a general paper from Shell on well chemical evaluation but little else. That shows how oil companies have come to rely on others to do performance testing. The shale business has not shown much interest in chemical performance until recently. Greater attention has turned to the many details that can incrementally improve shale well performance and to the research showing how friction reducers perform badly due to chemical reactions in some wells. These are not the only additives that may be affected by chemical reactions during and after fracturing. But friction reducers have grabbed the most attention because they do a couple important jobs.