Expro completes Enhanced Drilling acquisition, implications for geothermal MPD and RMR applications
Summary
Expro’s acquisition of Enhanced Drilling, bringing managed pressure drilling (MPD) and riserless mud recovery (RMR) into its global portfolio, is significant for geothermal developers and drilling teams. MPD offers fine-grained control of bottomhole pressure that directly addresses narrow drilling margins, lost-circulation risk, and inflow, underbalance events common in deep, high-temperature geothermal wells and engineered geothermal systems (EGS). RMR’s capabilities for capturing and recovering drilling fluids without a riser translate to lower logistics costs and reduced environmental footprint on shallow offshore or nearshore geothermal projects and onshore marginal sites where cuttings handling is constrained. For geothermal operations, integrating MPD and RMR can improve drilling efficiency, reduce nonproductive time (NPT), lower fluid consumption, and broaden feasible development options for complex reservoirs. This article examines technical synergies, practical use cases, engineering challenges, and an implementation roadmap tailored for geothermal projects.
MPD and RMR are proven offshore oilfield technologies focused on dynamic pressure control and efficient fluid handling. Geothermal drilling shares many subsurface challenges, narrow mud-weight windows, severe losses in fractured zones, high-temperature conditions, and the need for precise pressure management to protect reservoirs and well integrity. Expro’s consolidation of Enhanced Drilling’s MPD and RMR assets under a broad service platform increases access to specialist systems and operational experience relevant to geothermal projects, including deep, high-enthalpy wells, EGS stimulation-ready wells, and marginal or nearshore developments.
Technical primer, MPD and RMR for geothermal engineers
- Managed pressure drilling (MPD), a suite of surface and subsurface technologies plus procedures that actively control equivalent circulating density (ECD) and bottomhole pressure in real time. MPD methods relevant to geothermal include surface backpressure control (using rotating control devices (RCDs), automated chokes, and high-precision pressure sensors), constant bottomhole pressure (CBHP) modes for transition-zone drilling, and underbalanced, overbalanced strategies adapted for geothermal formation behavior.
- Riserless Mud Recovery (RMR), a fluids-handling system that collects and processes returned drilling fluids and cuttings without deployment of a riser column. For geothermal, RMR is applicable to nearshore or shallow-water geothermal sites and to onshore operations where minimizing surface discharge and optimizing fluid reuse are priorities.
Why MPD and RMR matter for geothermal drilling
- Controlling narrow pressure windows, deep geothermal reservoirs and EGS targets often present slim margins between pore pressure and fracture gradients. MPD enables controlled drilling within these windows, reducing the risk of induced fractures, lost circulation, or uncontrolled inflows that can compromise reservoir quality.
- Mitigating losses and protecting reservoir permeability, dynamic pressure control reduces the likelihood and severity of mud losses into permeable, faulted, or fractured zones, preserving reservoir permeability and minimizing the formation damage that can reduce long-term productivity.
- Enabling complex well paths and sidetracks, MPD allows drilling across transition zones and through variable lithologies with fewer casing strings, facilitating longer productive intervals, important for maximizing heat exchange in single wells or for complex multi-lateral geothermal designs.
- Fluid stewardship and environmental compliance, RMR reduces fluid discharge volume and increases recovered fluid for reuse, aligning with environmental requirements and reducing freshwater consumption for onshore or nearshore geothermal operations.
- Reducing NPT and improving economics, tight pressure management reduces stuck-pipe, lost-circulation remediation, and well-control events, lowering NPT and overall drilling cost per meter, critical for capital-constrained geothermal projects.
Geothermal use cases where MPD + RMR deliver value
- Deep, high-temperature hydrothermal wells, in wells exceeding 3, 4 km with high formation pressures and geothermal gradients, MPD’s ECD management and controlled depressurization during tripping minimize thermal and pressure shocks to the formation.
- Engineered Geothermal Systems (EGS) drilling and stimulation, EGS wells require precise pressure control during drilling and stimulation to avoid premature hydraulic fracturing or unintended connectivity; MPD enables more predictable wellbore pressure regimes during stimulation-prep operations.
- Transition-zone drilling across overpressured caprocks, where caprock integrity matters for reservoir containment and stimulation isolation, MPD reduces the risk of breaching pressure barriers unintentionally.
- Nearshore and island geothermal projects, RMR allows riserless recovery of drilling fluids for shallow offshore geothermal rigs and supports stringent environmental regimes common in coastal or island settings.
- Well interventions, sidetracks, and re-entry operations, MPD enables safer re-entry into high-temperature wells, where conventional well-control margins are reduced by temperature-dependent fluid properties and altered in-situ stresses.
Engineering considerations specific to geothermal
- High-temperature materials and electronics, geothermal wells expose tools and downhole sensors to higher temperatures than many oil and gas wells. MPD systems intended for geothermal use must employ temperature-tolerant sensors, seals, and telemetry systems, or place sensitive components at depth-protected positions.
- Fluid chemistry and cuttings behavior, geothermal brines can be corrosive and chemically active. RMR and surface processing systems must be designed for corrosive fluids, scale formation, and dissolved solids management to avoid rapid equipment degradation and to ensure effective reuse.
- Thermal effects on drilling fluids and ECD, temperature gradients alter fluid rheology and density, MPD control loops and ECD models must incorporate temperature-dependent properties for accurate bottomhole pressure control in geothermal columns.
- Cementing, casing, and long-term integrity, using MPD to limit the number of casing strings can be advantageous economically, but geothermal cement and casing designs must account for thermal cycling and corrosive fluids. Well designs should integrate MPD-led strategies with long-term integrity modeling.
- Reservoir protection, geothermal reservoirs are often more sensitive to fluid invasion and chemical alteration. MPD programs should be paired with low-invasion drilling fluids and cuttings containment strategies to limit reservoir damage.
Practical benefits quantified for geothermal projects, illustrative
- NPT reduction, for geothermal wells prone to lost circulation and stuck pipe, MPD has demonstrated reductions in pressure-related NPT comparable to hydrocarbon applications, often in the 25, 50% range depending on geology and baseline performance.
- Fluid and logistics savings, RMR recovery rates above 70% can substantially reduce makeup fluid needs and transportation costs for remote geothermal sites, lowering capex and operational footprints on island and rural projects.
- Faster well delivery, by minimizing circulation losses and avoiding time-intensive loss-control operations, such as squeeze cementing and lost-circulation materials, MPD can shorten drilling schedules, reducing exposure to daily rig premiums and personnel risk.
Note, quantify outcomes with project-specific models that include rig rates, local logistics, and fluid chemistry impacts.
Integration and operational challenges for geothermal teams
- Adaptation of control systems, MPD control algorithms and ECD models must be calibrated to geothermal fluid properties, including brine densities, non-Newtonian additives, and temperature-dependent viscosity. Telemetry links need to withstand high temperatures and possible electromagnetic interference in volcanic regions.
- Training and competency, geothermal crew competencies differ from oil and gas crews. Training programs must cover MPD theory, geothermal-specific well-control dynamics, thermal hazards, and environmental compliance aspects.
- Equipment spec and maintenance, corrosion-resistant materials, high-temperature seals, enhanced heat-sink designs, and robust power systems are necessary. RMR systems must include treatment modules for scale, silica handling, and brine reinjection compatibility.
- Regulatory and permitting considerations, geothermal projects face varied environmental and water-rights regulations. Implementing RMR can simplify permits by reducing discharge, but operators must confirm local acceptance of recovered-brine handling and reinjection plans.
- Reservoir sustainability concerns, overly aggressive pressure management could unintentionally create pathways that change reservoir behavior or induce seismicity in fragile EGS settings. Pressure-management plans should be coordinated with reservoir engineers and microseismic monitoring.
Implementation roadmap for geothermal projects
1. Feasibility and fit-for-purpose analysis, compare baseline drilling programs with MPD, RMR-enabled designs, focusing on geological uncertainties, expected losses, and reservoir sensitivity.
2. Well-program redesign, reassess casing points, cementing schedules, and mud programs to take advantage of MPD’s ability to drill narrower margins. Model thermal effects on ECD and downhole tools.
3. Equipment selection and specification, specify MPD components and RMR recovery systems with geothermal-grade materials, high-temperature sensors, and cuttings-handling modules compatible with local brine chemistries.
4. Data and control architecture, define SCADA, telemetry, and data-storage needs. Ensure MPD control algorithms incorporate temperature-dependent fluid models and interface with reservoir monitoring systems.
5. Competency and training, implement supervised pilot programs with joint provider, operator teams. Train rig crews, drilling supervisors, and reservoir engineers on MPD procedures and emergency reversion plans.
6. Pilot deployment and validation, start with one or two wells to validate fluid-recovery rates, sensor performance, and pressure-control reliability in the specific geothermal context.
7. Environmental and regulatory alignment, coordinate with regulators early on to confirm RMR discharge, reuse pathways, reinjection plans, and monitoring requirements.
8. Monitoring and continuous improvement, integrate MPD logs with production and reservoir models, using analytics to refine future well designs and to detect early signs of reservoir stress or connectivity changes.
Case study scenarios, hypothetical illustrations
- Deep hydrothermal well, 3.8 km, high-temperature, MPD applied in CBHP mode allowed drilling through a 150 m transition zone without lost circulation, saving an estimated 8, 12 rig days versus the contingency-heavy conventional plan. RMR was not used due to onshore location, but lessons on fluid management reduced mud consumption by 20%.
- Nearshore island project, shallow offshore geothermal, using RMR recovered 78% of drilling fluid volumes, eliminating offshore discharge and reducing transported makeup fluid by half. MPD mitigated shallow overpressure zones, avoiding several potential kicks during conductor and surface-hole drilling.
- EGS stimulation prep well, MPD provided controlled depressurization while tripping-in tools and allowed precise management of bottomhole pressure prior to hydraulic stimulation, reducing the need for sidetracks and improving stimulation targeting accuracy.
Strategic outlook for geothermal industry adoption
- Increasing relevance for deeper and EGS projects, as geothermal developers pursue deeper, higher-enthalpy resources and engineered reservoirs, MPD will become more attractive to manage narrow margins and protect reservoir integrity.
- Cross-industry technology transfer, oil & gas service providers consolidating MPD and RMR capabilities, like Expro’s acquisition, lower barriers to access for geothermal operators, accelerating the adoption curve.
- Digital integration and predictive control, combining MPD telemetry with reservoir models and microseismic feeds supports closed-loop control strategies that optimize drilling while minimizing reservoir impact.
- Regulatory and sustainability drivers, tightening environmental standards and community sensitivity to discharge in geothermal regions will favor RMR and fluid-reuse strategies.
Risks and limits in geothermal contexts
- Thermal and chemical compatibility, not all MPD, RMR systems are ready for extremely high temperatures or aggressive brines. Equipment must be validated for specific reservoir chemistries and temperature ranges.
- Induced seismicity and reservoir integrity, pressure management and stimulation must be coordinated to avoid creating unwanted connectivity or seismic events in EGS projects.
- Cost-benefit variability, for shallow, low-temperature sites with simple geology, MPD, RMR may not be cost-effective. Economic modeling should precede adoption decisions.
- Skills and cultural gaps, geothermal teams may need time to assimilate MPD operational culture and decision-making frameworks from the oil & gas domain.
Conclusion, technical significance for geothermal operations
Expro’s incorporation of Enhanced Drilling’s MPD and RMR capabilities broadens the technical toolbox available to geothermal developers. For deep hydrothermal and EGS projects, where narrow pressure margins, formation sensitivity, and logistics constrain drilling, MPD and RMR offer tangible operational benefits, improved pressure control, reduced NPT, lower fluid consumption, and smaller environmental footprints. Successful geothermal adoption requires equipment adapted for high temperatures and corrosive fluids, calibrated control systems, trained personnel, and careful reservoir-coupled planning to avoid unintended impacts. When applied judiciously, MPD combined with robust fluid-recovery strategies can lower drilling risk, expand feasible development scenarios, and improve the economics of next-generation geothermal projects.
Source: World Oil
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