The term “downturn” is one that most oilfield services companies know all too well. However, for two companies based 3,218 km (2,000 miles) apart, it means something more. It was during the lowest activity and commodity price levels of 2016 when Energes Oilfield Solutions and Dynacorp Energy Services developed a business partnership that would not only eventually unite them into a single company, EnerCorp Sand Solutions, but also bring production systems to operators through innovation and service.
“The opportunity to introduce new technology to the market was timely in this downturn as costs were being scrutinized at every level in the well life cycle,” said EnerCorp CEO Justin Morin. “E&P companies were looking to maximize production more efficiently, safely and without equipment failure due to sand erosion.”
Sand usage per well has been the hottest growth segment for the completions industry during the past couple of years as operators increase lateral lengths and push proppant per lateral foot well above historic levels. The largest wells now consume upward of 5,500 tons of sand per well, which is up from 1,500 tons just a few years ago. Credit Suisse projections of more than 2% sequential growth through 2018 means demand will grow from 33 million tons in 2016 to 60-million-plus tons in 2017 and 75 million tons to 90 million tons this year, with a sand usage per well growth of 15% to 20%.
U.S. Silica projects the usage could even go as high as 147 million tons in 2018. This increase in sand usage has presented production and midstream facility challenges that have never before been seen in the industry.
Managing increased sand
Traditional gravity-driven sand separators were the only option on the market to combat sand returns and still remain a staple for most completions and production groups. However, with the above-mentioned increase in sand usage, sand returns have increased sequentially. To address this, the company then known as Energes introduced a proprietary dual cyclonic sand separator with engineered inserts for second-stage solids separation.
Even with the increased efficiencies of the dual cyclones, the field tests that were conducted using acoustic monitoring sensors downstream of the sand cyclone separators were registering that 10% to 25% of entering sand was still carrying over. Most would assume that this sort of efficiency is good enough. But 10% to 25% of a well flowing back 10 lb to 65 lb of sand per hour accumulates to a significant amount of sand over weeks and months of production, which in turn leads to excessive damage of piping and components at facilities.
In addition to the accumulating sand volumes building up at the production facilities, some E&P operators also were finding they were unable to drive strong well IP due to sand returns limiting their ability to run aggressive choke schedules. These growing challenges led the company then known as Dynacorp to introduce its patented sand filtration system that already had garnered success in the Canadian market.
On the first trial job of a Delaware Basin well— through the introduction of the filtration unit—the team enabled the operator to open the well up to a 41/64-in. choke, where previously it was limited to a 17/64-in. choke due to increasing sand issues in the production facility. Oil production increased by 200 bbl/d due to the increase in choke size, and gas production increased from 28 cu. m to 51 cu. m (1 Mcf/d to 1.8 Mcf/d).
Energes’ sand monitoring system showed only minute traces of sand downstream of the filtration unit, sending clean production to the facilities. A second operator was facing a very different issue with pump seals being destroyed on a daily basis at its central battery system. The operator was attempting to redesign how it managed production facilities and had found a more costeffective and operationally efficient design but was unable to manage the hourly returns of 30 gal to 65 gal of sand it was seeing. Since sand filter installation, after 120-plus days, candidate wells were opened to 64/64-in. choke and had no pump seals damaged.
The need to remove and reinstall the screen for cleanings presented an HSE concern due to the size and weight of the screens. Overhead gantry systems were designed and installed on the units to ensure the elimination of any bodily strain on the field operators managing the filter system. The Dynacorp engineering team also has developed self-cleaning screen applications to eliminate the need for screen removals. This not only eliminates HSE exposures but also drives down personnel costs to the operator.
Sand monitoring is another challenge facing the industry. Operators want to know what their sand volumes are entering the various sand management systems, how much sand is being removed from each stage, and how much sand is being passed through each system and into their production facilities. Various technologies on the market can provide data on solids intensity, but nothing had been developed showing accurate sand measurements in a live flow environment. This led EnerCorp to develop proprietary software using commercially available ultrasonic flow measurement equipment.
The inclusion of weight scales as a redundant and secondary backup has enhanced the accuracy of the data the ultrasonic sensors provide for E&P companies and operators to know when to clean and what volumes of sand are being made. The teams are further developing new technology to ease the maintenance, cleaning and time operators are required to be at the site. The self-cleaning screen system will provide operators the ability to wash down the accumulated sand inside the pressure vessel with high-pressure water while maintaining continuous flow. The concept to commercialization of the cleaning system is underway and is expected to be in full operation and mass production in first-quarter 2018.
Continued innovation with the cyclone design also has improved efficiencies. Through computation flow dynamic software flow modeling and engineering, EnerCorp developed multiple cyclone inserts to achieve the maximum efficiency of sand separation inside the pressure vessel with 100 μ sand. The teams learned the well parameters played an integral role in sizing the cyclone inserts. With the software the companies can model the conditions in which the well would flow through the cyclone and what efficiency it would achieve.