WATER. MANAGEMENT Responsible Solutions for North America s Oil and Gas Industry. Aeration: October 13, 14 NRG Center, Houston See Inside for Details!

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1 SHALE PLAY WATER MANAGEMENT Responsible Solutions for North America s Oil and Gas Industry September / October 2015 ShalePlayWaterManagement.com Join the Industry for October 13, 14 NRG Center, Houston See Inside for Details! Aeration: A Cost-Effective Water Management Strategy How Water Planning Pays Off for Energy Companies Plus... Advanced Filtration Automation in Real -Time and Much More!

2 The Benefits of Real-Time Automation for Your Water-Management Process Well-planned automation systems help operators gain efficiencies in control, energy use and maintenance. BY TED WILKE AND BOBBY MASON The volume of flowback and produced water returning from wells is dramatic and presents unique challenges to production operations. Automation solves many of these challenges, centralizing pump control and gathering key data points for each tank and disposal well. Anywhere access ensures 24/7 availability to data. With the dramatic increase in unconventional plays, water management has become a significant element in oilfield economics. Fracking jobs in unconventional plays routinely put 10 times the fluid downhole as was in conventional plays. As much as 250,000 barrels of fluid is used during completion for each well. The flowback from these wells is often high volume, varying by play and even by well. As much as 40 percent of the initial volume 100,000 barrels returns to the surface. Produced water flows from the formation along with hydrocarbons throughout the life of the well. Automation plays a key role in optimizing movement and disposal of flowback and produced water, ensuring no overflow or under-utilization conditions. It is invaluable in 84 Shale Play Water Management September / October 2015

3 Disposing of saltwater through injection applications puts incredible stress and wear on the pump. Traditional solutions run the pump at full speed and use a valve to choke back pressure to the optimum level. The VFD offers an alternative solution that greatly reduces wear on your system, helping you operate more efficiently complying and reporting pressure and rate requirements. Through automation, great efficiencies can be gained in control, energy use and maintenance. TRANSFER-TANK MANAGEMENT Flowback and produced water are staged in transfer tanks for separation, recycling, reuse and disposal. Huge volumes must be best managed to optimize conditions for operators of the production well and disposal site. Typically, every tank has an associated pump, and tank level or pressure are used as the control mechanism. Tank overflows, pump failures and pipeline leaks are all unacceptable, given that the fluid contains salt water, oil and other contaminants. Tanks must be continuously monitored to avoid overflow penalties and cleanup costs. When tank levels reach a predetermined high point, no more fluid is admitted. If pressure exceeds a pre-set limit, action must be taken. Transfer-tank pump management is a labor-intensive function ripe for automation. Shale Play Water Management September / October

4 WATERFLOOD CONTROL Produced water including flowback is sometimes used for waterflood to increase downhole pressure in production wells. In these cases, water may be staged and treated near the well site. Injection pumps are typically used to move water into the well. Pumping units must be carefully checked to prevent over-pressure and premature equipment failure. Bypass valves are particularly vulnerable to failure, risking significant downtime. Automation of pump-equipment control reduces labor costs for monitoring and unplanned maintenance. SALTWATER DISPOSAL If disposal facilities are not pushing water into the ground, they are not making money. These operations need to keep up with the fluid coming into the facility. At the same time, the operator must constantly monitor pressure and rate to maximize operations without exceeding regulatory requirements. These are difficult tasks if they remain manual. Pumps are key components of saltwater-disposal facilities because they are the mechanism that moves the fluid from holding areas to separation, treatment and disposal. Controlling all pumps onsite so that they work in concert is critical. So is managing all sensor data revealing pressures, tank levels, flow and motor conditions. EFFICIENT CONTROLS A fully connected saltwater-disposal site typically has a variable frequency drive for every pump. Sensors are deployed to measure pressure, flow, tank levels and more. Drives are configured with limits to allow smart, continuous operation. Notifications, warnings and alarms are activated when limits are reached. All data points are connected to a master system that provides site-level monitoring. Adjustments can be made at the local equipment or master level, giving operators flexibility. All data is available for monitoring and control onsite and away. Operations that rely on manual controls with a technician checking gauges and pumps, turning on and off based on tank levels, have a big opportunity for efficiency gains through automation. Connecting a pumping unit to a drive system instantly increases access to critical pump and tank data. Operators set each pump s optimal operating parameters, leading to better usage. Connecting the drive to the Internet enables remote monitoring for anywhere access and insight. Operators can react quickly to negative trends and alarms, 86 Shale Play Water Management September / October 2015

5 The variable frequency drive controls the speed at the pump, allowing you to leave the valve open at all times, reducing wear and failures within the system. The drive s simple interface allows you to control and monitor your tank levels, vibration sensors, intake pressure and discharge pressure. An operator can control the pump at the widest possible range. Without distributed pump control, if a fuse is blown or the programmable logic controller (PLC) fails, the site is either down or running in hand, requiring constant intervention. identify developing problems and take remedial action using their mobile devices. With routine adjustments made automatically, technicians are free to focus on getting the most out of operations. Operators choose their control mechanism. With tanklevel control, the drive speeds up if the tank level is above setpoint, slows down if below the setpoint and stops if below the minimum level. With pressure control, the unit regulates itself to the discharge pressure setpoint, and starts and stops based on tank-level settings. At sites with more than one tanks and/or disposal wells, distributed pump control provides additional efficiency. Each pump has an associated motor and control panel. All the safeties and signals tie to that panel, making a complete unit within an overall control system. Field devices terminate in the drives. A master panel monitors and controls site conditions such as oil-tank levels, settling tank level, makeup freshwater volume, lead/lag control, run hours and wear sharing. Each drive ties into the master. If the connection to the master is lost, the drive systems continue to do their jobs independently. Communications technology makes the data from any panel accessible from wherever it is needed at the master panel, in the office or from a pickup down the road. Without distributed pump control, if a fuse is blown or the programmable logic controller (PLC) fails, the site is either down or running in hand, requiring constant intervention. This increases cost, reduces efficiency and can incur safety violations if safeties are not set up for work in hand. For off-site or centralized monitoring and oversight, drives can be configured to communicate data via SCADA. This Shale Play Water Management September / October

6 West Texas producer finds major benefit with intuitive touch-screen technology at an SWD site. makes real-time data accessible anywhere using smart devices. Alarms and emergency calls are automatically initiated based on pre-configured limits. Data analysis identifies maintenance tasks that can be done proactively for the fastest turnaround. Any additional data can be collected and connected as long as it is SCADA-compliant. Common data such as drive and sensor are available through dashboards. User interfaces are extended to incorporate additional data such as sensor readings and controller status. They can also be configured for specific data analyses required by individual businesses. And they can be connected with specialty data from field-service ticketing systems and more. Field notes are recorded digitally and correlated to the equipment data, making it easier for other personnel to understand the full situation and identify patterns over time. Real-time data can be analyzed and reports generated. Trends can be observed and informed decisions rendered. ENERGY EFFICIENCY Another area where automation significantly improves efficiency is in energy use. Drives reduce energy consumption by continuously changing pump speed to match what is needed. This lowers the energy bill by 20 percent and potentially much more. Remote monitoring of drives in the field identifies voltage spikes and surges that can cause early equipment failure. And alarms can be set and reports generated for addressing electrical-service issues. It is possible to outfit drives to clean electricity, removing harmful harmonics and improving power factor. Reducing harmonics improves transformer efficiency, reduces high current-induced overheating, minimizes interference and improves power quality. The high-power factor eliminates fines from the utility company for wasting current. Place a drive between the utility and pumping equipment, and the drive will satisfy the non-work current requirements from the pumping equipment without drawing from the utility. As a consequence, the power factor will be very high 95 percent or more. Another great saving in energy use and facility space is using low-voltage drives instead of medium-voltage drives. Low-voltage drives are cheaper, smaller and easier to maintain than medium-voltage drives. Typically, low-voltage drives cost less than half that of medium voltage. Both low- and medium-voltage drives require a transformer a 4160 VAC to 480 VAC step-down input isolation transformer in the case of low voltage. Low-voltage drives are more common, simpler to operate and easily control 600-horsepower pumps. Medium voltages are almost always installed, started up, repaired and maintained by the manufacturer s field-service team. MAINTENANCE EFFICIENCY Efficiency in service and repair translates directly into money saved and money earned. Automation protects equipment by reducing the mechanical stress and strain it encounters. It provides better insight into equipment status so that operators can schedule proactive maintenance rather than react to equipment failure. Drives do not over- or under-power pumps. They protect the motor and pump from inrush current and voltage surges that cause overheating and insulation failure. Less wear and tear means a longer operating life. 88 Shale Play Water Management September / October 2015

7 Common causes of premature equipment failure include abrupt starts and stops. This constant abuse will eventually lead to early maintenance or failure, extra expense and lost revenue. Drive systems avoid many of these damaging conditions by closely controlling pump speed, and continually monitoring and adjusting the pump speed to optimize performance. Because pump speed is controlled at all times, there are fewer times the pump will need to stop. The drive system itself also presents a maintenance challenge if it is custom built rather than pre-integrated. The full inrush of current also puts the equipment at risk for burnout. While soft starters can reduce the current by about 50 percent, this is still two to four times the pump rating. Drives never go over the full load amperage. This approach extends equipment life. For injection pumps, the bypass valve is subject to severe stress in the absence of a drive. Failure is an expensive and avoidable condition that might cause shutdown for 10 hours to several days. Unscheduled maintenance may require overtime or double time while safety checks are performed, the valve replaced and pump brought back online. Using a drive that adapts to pump and downhole conditions extends the lives of bypass valves and other mechanical components. The drive system itself also presents a maintenance challenge if it is custom built rather than pre-integrated. Unplanned service calls are troublesome if there are several vendors involved, as it may be difficult to know who to call and how to coordinate efforts. Keeping automation equipment simple adds greatly to no-hassle service. Early drive systems required as many as six to eight vendors onsite to install, program and integrate. One did the wiring, another the installation and another took care of communication. This overly complex approach required many technicians for setup, installation and service. In addition, these traditional pump-automation systems had all pump, tank and sensor controls tied to the PLC, which then directed the drive. If the PLC failed, the drive went blind to the pump environment. Worse, if there were multiple drives controlled by a single PLC, the entire facility went blind upon PLC failure. Now pre-integrated systems remove the complexity through standardization. It is not necessary to reinvent the wheel for every project. The PLC and drive come pre-config- Shale Play Water Management September / October

8 ured and pre-integrated, eliminating the need for a separate PLC and its integration. Onsite installation is fast and economical because there is no need for subsystem integration. In our experience, 80 percent of all pump-automation and control systems use the same eight to 10 signals. Pre-integrated drive systems come with these signals, core-monitoring capability and communications. These systems are then configured onsite no programming and are much more easily maintained. Pre-integrated systems reduce installation expenses, exposure to the elements and the cost of automation failure. SMOOTH, CONSISTENT PROCESS Everyone benefits from smooth, consistent shale-play water management. Producers can rely on efficient and safe transfers away from the well. Disposal-site operators can count on steady volumes moving from trucks through separation to disposal wells or recycling. Regulators have compliance documentation on safety, pressure and rate rules. Automation brings significant improvements in efficiency by taking over the time-consuming tasks of monitoring and adjusting tank levels, pressures and flow rate within pre-set limits. Potential issues are flagged before a shutdown or failure occurs. Operators are freed to turn their attention to proactive maintenance, trending and optimization. About the Authors: Bobby Mason is President of SPOC Automation, which builds worldclass artificial lift controls and well automation solutions for the oil and gas industry. Mr. Mason has 26 years of experience in the electrical industry and 15 years specializing in oil and gas automation systems. Ted Wilke is Vice President of SPOC Automation. He has 18 years of experience in the electrical industry, including 13 years specializing in control systems and five years specializing in power-distribution systems. 90 Shale Play Water Management September / October 2015