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Technical articles on process engineering, simulation, process safety, and project management — written by engineers with over 100 years of combined upstream oil & gas experience.
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Safety · Process
Pressure Relief and Flare Systems — A Design Overview
Relief valves, blowdown, the flare header, the stack, and the high-integrity instrumented layer all answer one question — how does this facility shed pressure and energy safely? This overview joins them into one picture and points to the deep-dives on each part.
Read guideSafety
The Process Safety Lifecycle — From HAZID to ALARP
HAZID, HAZOP, LOPA, SIL, the functional safety lifecycle, cause-and-effect matrices, bow-ties and the ALARP demonstration are not a pile of separate studies — they are one connected chain. This overview sequences them and shows how each feeds the next.
Read guideProcess · Subsea
Flow Assurance Study Scope for a Subsea Tieback
A practical guide to the inputs, simulation cases, decision gates, and deliverables required to prove that a subsea tieback can operate, shut down, and restart safely before project sanction.
Read guideProcess · Simulation
How to Conduct a Production Facility Bottleneck Study
A practical troubleshooting method for finding the constraints that actually limit an oil and gas facility, validating them against operating data, and turning the results into a ranked production-improvement plan.
Read guideBrowse by project decision
EC&I · Safety
Alarm Rationalisation: From Alarm Floods to a Philosophy That Works
An alarm system that announces everything protects nothing. How ISA-18.2's lifecycle and EEMUA 191's benchmarks turn a nuisance flood into an alarm system operators can actually use on the worst day of the year.
Rob BinnerProject Management
Anatomy of a Class 3 Cost Estimate: Basis, Contingency, and What Sanction Reviewers Check
A Class 3 estimate is not a spreadsheet with better formatting — it is an engineering deliverable with a defined basis, a defensible contingency, and an accuracy claim that has to survive a sanction review. Here is what goes into one.
Jose CampinsEC&I · Simulation
Anti-Surge Control: Designing the Loop That Protects Your Compressor
Surge can destroy a centrifugal compressor in seconds, and the loop that prevents it is unlike any other on the facility — millisecond decisions, a valve with contradictory duties, and a controller that must never be tuned casually.
Rob BinnerProcess
What Operations Wishes Engineering Knew Before First Oil
After three decades on the operator side of the fence, the same design decisions keep surfacing at 3 a.m. — not as calculations, but as a valve you cannot reach, an isolation you cannot prove, and a sample you cannot take.
Ian BissettProject Management
Preparing an RFQ Package That Gets You Comparable Bids
Three bids on the table, three different scopes, three different exclusions lists — and no honest way to compare them. Most tender evaluations fail before the first bid arrives, in the quality of the RFQ package itself.
Darren StrengersProcess
CO₂ Corrosion: Prediction, Materials Selection, and Where Carbon Steel Is Still Fine
Sweet CO₂ corrosion retires more upstream pipework than any other damage mechanism, yet the answer is not always exotic metallurgy. How the rate is predicted, what actually controls it, and the cases where carbon steel with a corrosion allowance remains the right choice.
Jose CampinsProcess · Simulation
When Is API 618 Design Approach 3 Required? Reciprocating Compressor Pulsation and Vibration Studies
How to decide when a reciprocating compressor needs a Design Approach 3 pulsation and vibration study—and how to specify, schedule, review, and implement the analysis before the package piping is frozen.
Jose CampinsSafety · Project Management
Pre-Startup Safety Review: What Must Be Closed Before Hydrocarbon Introduction
A PSSR is not the last construction meeting or a demand for zero punch items. It is the evidence-based decision that containment, safeguards, procedures, people, and emergency arrangements are ready before the first hydrocarbon crosses the system boundary.
Darren StrengersProcess · Simulation
Why Is My TEG Unit Producing Off-Spec Gas? A Troubleshooting Guide
A practical, evidence-led method for diagnosing high water content and poor dewpoint performance in a TEG gas dehydration unit—from sampling errors and lean glycol quality to contactor hydraulics and regeneration limits.
Jose CampinsProcess · Simulation
TEG Regenerator Design — Reboiler Duty, Stripping Gas, and Lean Glycol Purity
How a TEG regenerator converts rich glycol back into a dry absorbent—and how reboiler duty, stripping gas, heat recovery, and still overhead design determine the lean glycol purity a gas dehydration unit can actually sustain.
Jose CampinsProcess · Subsea · Simulation
Flow Assurance Study Scope for a Subsea Tieback
A practical guide to the inputs, simulation cases, decision gates, and deliverables required to prove that a subsea tieback can operate, shut down, and restart safely before project sanction.
Jose CampinsProcess · Simulation
How to Conduct a Production Facility Bottleneck Study
A practical troubleshooting method for finding the constraints that actually limit an oil and gas facility, validating them against operating data, and turning the results into a ranked production-improvement plan.
Jose CampinsSafety · EC&I
SIS Proof Testing and Partial-Stroke Valve Testing
A safety instrumented function spends its whole life doing nothing, waiting for the one demand that matters. The only way to know it will still act on that day is to test it — and the test interval, not the hardware, is what actually sets the SIL you achieve. Proof testing is where the safety case is either kept honest or quietly eroded.
Jose CampinsSubsea · Process
Subsea Tieback Design and Flow Assurance
A subsea tieback moves the wells kilometres from the host and leaves the fluids to cool on the seabed the whole way. Everything that can go wrong in that pipeline — hydrates, wax, slugging, a cold restart that never restarts — is a flow assurance problem, and it has to be solved on paper years before first oil.
Jose CampinsProcess
Sizing a Shell-and-Tube Heat Exchanger: LMTD, TEMA and Fouling
A heat exchanger that is a few square metres short never announces itself on the datasheet — it shows up two years later as an off-spec product or a compressor tripping on high suction temperature. Sizing one correctly is a chain of four numbers: duty, LMTD, U, and area. Miss the fouling allowance and the whole chain fails slowly.
Jose CampinsSafety
The Process Safety Lifecycle — From HAZID to ALARP
HAZID, HAZOP, LOPA, SIL, the functional safety lifecycle, cause-and-effect matrices, bow-ties and the ALARP demonstration are not a pile of separate studies — they are one connected chain. This overview sequences them and shows how each feeds the next.
Rob BinnerSafety · Process
Pressure Relief and Flare Systems — A Design Overview
Relief valves, blowdown, the flare header, the stack, and the high-integrity instrumented layer all answer one question — how does this facility shed pressure and energy safely? This overview joins them into one picture and points to the deep-dives on each part.
Jose CampinsProcess · Subsea
Wax and Asphaltenes — The Two Solids That Block a Subsea Tieback
Hydrates get the attention, but two other solids quietly close flowlines: wax that crystallises when the oil cools below the wax appearance temperature, and asphaltenes that drop out when the pressure falls through their onset envelope. They are different problems with different cures, and a tieback designed for one can still be killed by the other.
Jose CampinsEC&I
Fiscal and Allocation Metering — Measuring What Everyone Gets Paid For
When hydrocarbons change ownership, the meter is the cash register — and when several fields share one facility, the allocation metering decides who owns what came out. Get the technology and the uncertainty budget wrong and you are not making an engineering error, you are mis-paying the partners.
Rob BinnerSafety · EC&I
HIPPS — When an Instrumented System Replaces the Flare
Some overpressure scenarios are too big to flare your way out of. A High Integrity Pressure Protection System closes fast valves to isolate the source before the downstream equipment is overpressured — trading an enormous relief and flare system for an instrumented safeguard you have to prove to SIL 3 and test for the life of the field.
Rob BinnerProcess
Produced Water Treatment — From the Separator Water Leg to Overboard
Every barrel of oil eventually comes with barrels of water, and that water has to go somewhere clean enough to discharge or reinject. The produced water system is the quiet workhorse that decides whether an EPF can actually keep producing — and it is the system most often undersized on a weight-limited deck.
Ian BissettProject Management · Process
Concept Selection for Marginal Fields — MOPU vs FPSO vs Fixed Platform vs Subsea Tieback
The development concept is the single decision that determines a marginal field's economics — and it is made when you know the least. A framework for choosing between a fixed platform, an FPSO, a MOPU, and a subsea tieback, and the drivers that actually decide it.
Darren StrengersSafety · Process
Emergency Depressurisation and Blowdown — The API 521 15-Minute Rule
Depressure to 50% of design pressure within 15 minutes — the rule everyone quotes and few derive. Working through where it comes from, how the fire case sets the load, how the blowdown orifice gets sized, and why auto-refrigeration quietly drives your material selection.
Jose CampinsProcess
Fuel Gas and Vapour Recovery — Making an Early Production Facility Self-Sufficient
An EPF wants to run on its own gas and flare as little as possible. The fuel gas system feeds the power plant; the vapour recovery unit claws back the flash gas you would otherwise burn. Both are small systems with outsized consequences if they are wrong.
Jose CampinsProject Management
Storage and Offloading Without an FPSO — FSOs, CALM Buoys, and Shuttle Tankers
When a MOPU or fixed platform has no export pipeline, the crude has to be stored on the water and handed to a tanker. The storage-and-offloading system is its own engineering problem — and it is what quietly sizes the whole development.
Darren StrengersProcess · Subsea
Pigging Philosophy and Pig Launcher / Receiver Design
A pipeline you cannot pig is a pipeline you cannot inspect, clean, or batch-treat. The philosophy choice — utility pigs, intelligent pigs, or no pigging — sets the launcher and receiver design, and that design is permanent. Here is the framework that gets it right at the front end.
Ian BissettProcess · Simulation
Crude Stabilisation and RVP/TVP Control — Multi-Stage Flash vs the Stabiliser Column
Get the vapour pressure wrong and the storage tank breathes hydrocarbons, the tanker rejects the cargo, or you leave stock-tank barrels in the gas. A working guide to RVP, TVP, and the two ways to hit the spec on a weight-limited topside.
Jose CampinsProcess
Material Selection for Sour Service — NACE MR0175 in Plain Language
NACE MR0175 / ISO 15156 governs metal selection wherever H₂S can crack steel. The standard runs to several hundred pages — the operating principles fit on one. A practical guide to partial-pressure thresholds, qualified materials, and the audit trail the operator needs to defend the choice.
Ian BissettProject Management
Greenfield vs Brownfield CAPEX Estimating: AACE Class Progression in Practice
AACE cost estimate classes describe the maturity of the estimate, not the quality of the engineering behind it. Understanding the difference is what separates a useful estimate from a number that will be wrong in expensive ways.
Darren StrengersSafety · Project Management
What an Independent Engineering Review of a MOPU Actually Checks
A MOPU is a leased, converted asset with a history you did not write, on a schedule that skipped steps. Before an operator accepts it, an independent review tests the offering against the requirements, the standards, and the regulator — across six dimensions that decide whether it is fit for the field.
Darren StrengersProcess · Subsea
Sand Erosion Management Beyond API 14E — DNV-RP-O501 in Practice
API 14E's C-factor is a screening tool, not a sand model. When solids are in the stream, the controlling component is the choke or the first elbow downstream — and DNV-RP-O501 is the framework that actually sizes them.
Jose CampinsSafety · Project Management
ALARP Demonstration in Practice
ALARP is two letters at the end of a safety case and an obligation that runs through every design decision. The UK Health and Safety at Work Act expects gross disproportion in the cost-benefit comparison — what that means in practice, and where designs go wrong.
Ian BissettProject Management
Pre-Commissioning: Flushing, Drying, and Nitrogen Purging in Practice
Pre-commissioning is where construction quality is verified and hidden defects surface. Flushing, drying, and nitrogen purging are the three operations that most commonly determine whether commissioning starts on time or starts late.
Darren StrengersSafety · Process
Flare Radiation and Siting — API 521 Thermal Contour Analysis
The flare is sized by the header; the flare stack is sized by radiation. Working through API 521 Table 5, the Brzustowski-Sommer model, and how the 1500 BTU/hr·ft² contour ends up setting the plot plan.
Jose CampinsProject Management
MOPU and EPF Lifecycle: Lease, Convert, Operate, Demobilise
A Mobile Offshore Production Unit is a financial instrument as much as it is a piece of engineering. Its lifecycle — acquisition, conversion, operation, redeployment — is what makes early production economic, and what makes it hard.
Darren StrengersProject Management
Commissioning and Start-Up Sequencing for Oil and Gas Facilities
Most schedule overruns at the end of a project are not engineering or construction problems — they are commissioning problems caused by sequence decisions made months earlier. Getting the sequence right is the work.
Darren StrengersProcess · Subsea
Two-Phase Pipeline Flow Regimes and Slug Catcher Sizing
Long-distance multiphase pipelines do not flow as homogeneous mixtures — they flow as stratified, slug, annular, or mist regimes depending on conditions. The slug catcher exists because terrain-induced slugs are unavoidable in real pipelines, and getting it right is the difference between a steady production train and one that trips on every pig.
Jose CampinsProject Management
Brownfield Tie-In Engineering: Hot Tap vs Shutdown Planning
Every brownfield modification eventually comes down to one decision: tie in live, or take the plant down. The choice drives cost, schedule, risk, and the rest of the engineering scope — and it must be made early.
Darren StrengersEC&I · Process
Control Valve Sizing — Cv, Choked Flow, and Trim Selection
A control valve undersized by 20% will hunt, a valve oversized by 50% will throttle on the seat. ISA 75 / IEC 60534 gives the equations — choosing the right Cv, trim, and characteristic is the part that takes judgement.
Rob BinnerProcess · Simulation
Gas Sweetening with Amines — MDEA, MEA, DEA, and Mixed Solvents
Sour gas containing H2S or CO2 fails sales spec, corrodes carbon steel, and is fatal to operators at low concentrations. Amine gas sweetening is the proven defence — but selecting the right amine, designing the absorber, and protecting the regenerator from thermal degradation requires more than dropping MDEA into a flowsheet.
Jose CampinsProcess · Subsea
API 14E Erosion Velocity and Sand Management in Early Production
API 14E gives a one-line correlation that has sized offshore piping for forty years — and is now the most argued-about equation in subsea engineering. Here's what the C-factor really represents, when the conservative limit is right, and where modern guidance moves it.
Jose CampinsSafety
Bow-Tie Analysis — Threats, Barriers, and Consequences
HAZOP finds hazards. LOPA quantifies their frequency. Bow-tie analysis sits between them — visualising the prevention and mitigation barriers between every threat and every consequence, and exposing where a single failure leaves the system unprotected.
Jose CampinsProcess
Centrifugal Pump Sizing and NPSH
Pump cavitation destroys impellers, drops capacity, and shakes piping apart — all because the suction pressure didn't quite clear vapour pressure. NPSH is the calculation that prevents it. Done correctly, the pump runs for twenty years; done badly, it eats itself in six months.
Jose CampinsSimulation
Choosing the Right Property Package: An EOS Selection Guide
Process simulators offer dozens of thermodynamic models and the wrong choice silently corrupts every result downstream. This is a service-by-service guide to picking the right one — cubic EOS, activity coefficient, GERG, CPA, electrolyte — and knowing when each fails.
Jose CampinsSafety · Process
Flare Network Sizing and API 521 Blowdown
Once individual PSVs are sized, the relief load has to land somewhere. API 521 governs the contingency selection, simultaneous relief logic, and depressurisation rate that together determine the flare header, knock-out drum, and stack.
Jose CampinsProcess · Simulation
Hydrate Prediction and MEG Injection
Gas hydrates form in cold high-pressure pipelines, plug flowlines completely, and shut down production for weeks. The defence is thermodynamic inhibition with MEG or methanol — calculated from a phase envelope, dosed continuously, regenerated, and recycled. Get the rate wrong and the line plugs anyway.
Jose CampinsProcess · Simulation
TEG Gas Dehydration — Designing the Contactor and Regenerator
Triethylene glycol dehydration is the workhorse of pipeline gas conditioning. The contactor, the regenerator, and the lean-rich exchanger together drive the water dewpoint — and a handful of design choices determine whether the unit holds spec or limps along on chemicals.
Jose CampinsEC&I
SCADA, DCS, or PLC — Which Control System Does Your Upstream Facility Need?
SCADA, DCS, and PLC are not interchangeable acronyms for the same thing. Each has a distinct architecture, a distinct strength, and a context where it clearly outperforms the alternatives. Getting this decision right at FEED stage saves significant cost and avoids painful redesign at commissioning.
Rob BinnerSimulation
How to Size a Restriction Orifice Plate
Restriction orifices appear throughout upstream process systems — on bypass lines, compressor recycles, chemical injection headers, and pressure letdown applications. They are simple devices, but they are frequently undersized, oversized, or sized without checking for cavitation. Here is a rigorous approach to getting the calculation right.
Jose CampinsSafety
HAZOP vs HAZID: Choosing the Right Study for Your Project
Both appear on project safety study schedules, and both are called 'hazard studies'. But a HAZOP and a HAZID address different questions at different stages. Confusing the two — or substituting one for the other — leaves serious gaps in your safety case.
Jose CampinsSafety
Why Every Process Plant Needs a HAZOP
A HAZOP is not a box-ticking exercise — it is the most effective tool available for identifying process safety gaps before they become incidents. Here is why it is non-negotiable, what it uncovers, and what happens when it is skipped.
Jose CampinsSafety · EC&I
Functional Safety Management to IEC 61511: The Full Lifecycle Explained
SIL classification is just one step in a much longer process. IEC 61511 defines a complete safety lifecycle — from hazard identification through design, installation, proof testing, and eventual decommissioning. Understanding the full lifecycle is essential for anyone managing safety instrumented systems in the process industry.
Rob BinnerSimulation
Dynamic Process Simulation: When Steady-State Isn't Enough
Steady-state simulation answers the design question: what does the process look like at normal operating conditions? Dynamic simulation answers the operational question: what happens when it doesn't. Here is when you need dynamic simulation and what it can tell you that a steady-state model cannot.
Jose CampinsEC&I · Safety
Electrical Area Classification: Zone 0, Zone 1, and Zone 2 Explained
Electrical area classification determines what electrical and instrumentation equipment can be safely installed where. Getting it wrong puts facilities at risk of ignition. Getting it right — without being excessively conservative — keeps projects on budget and avoids equipment proliferation.
Rob BinnerEC&I
Cause and Effect Matrices: How to Structure a C&E for a Production Facility
The cause and effect matrix is the document that translates your P&ID interlocks into testable, auditable logic. A well-structured C&E prevents commissioning surprises, supports SIL verification, and gives operations a clear reference for every trip and alarm on the plant.
Rob BinnerProcess
Reciprocating vs Centrifugal Compressors: How to Choose the Right Machine
Compressor selection is one of the most consequential decisions in a gas processing project. Choosing the wrong machine type leads to poor turndown, excessive maintenance, or a compressor that simply cannot meet the duty. Here is how to make the right call.
Jose CampinsProject Management
What Is a FEED Study and Why Does It Matter?
Front End Engineering Design is the engineering phase that turns a concept into a fundable project. Done well, it defines scope, cost, and schedule with enough accuracy to get investment approved. Done poorly, it creates expensive problems in detailed design.
Jose CampinsSimulation
How to Size a Three-Phase Production Separator
Three-phase separators are among the most common pieces of equipment in upstream oil and gas. Sizing them correctly requires balancing gas capacity, liquid retention time, and water droplet settling — and knowing which constraint governs your design.
Jose CampinsSafety
Running an Effective HAZOP: Ten Lessons from the Field
A HAZOP study is only as valuable as the quality of its findings — and a poor facilitation can turn a critical safety exercise into an expensive rubber stamp. Here are ten lessons from years of leading and participating in HAZOP workshops across onshore and offshore projects.
Jose CampinsProject Management
Early Production Facilities: Design Principles for Fast-Track Upstream Projects
An Early Production Facility is not simply a smaller, simpler version of a full field development. It is a different type of engineering problem — one that demands a different set of design decisions, trade-offs, and delivery priorities.
Darren StrengersSafety
SIL Determination Using LOPA: A Practical Guide for Process Engineers
Safety Integrity Level determination is a core requirement for any Safety Instrumented Function protecting against a major hazard. LOPA provides the quantitative link between the hazardous event frequency and the risk reduction required from the SIS — but applying it correctly requires understanding several concepts that are frequently misunderstood.
Rob BinnerSimulation
Why Peng-Robinson EOS is a Good Default Choice
The Peng-Robinson equation of state is the go-to thermodynamic model in commercial process simulators for hydrocarbon systems. Here's why it earns that position — and where its limits lie.
Jose CampinsSafety
Why Routine Maintenance for Pressure Relief Valves (PSVs) is Non-Negotiable
A PSV that passes its installation inspection is not a PSV that will perform reliably five years later. Here is why routine maintenance is a safety-critical obligation, not a scheduled inconvenience.
Jose CampinsSafety · Simulation
How to Size a Thermal Relief Pressure Relief Valve (PSV)?
Thermal relief PSVs protect systems against minor, predictable overpressure scenarios. Sizing them correctly requires understanding the specific relief case — and why an oversized valve can be just as problematic as an undersized one.
Jose CampinsSafety · Simulation
When is a Thermal Relief PSV Needed?
Not every overpressure scenario requires a full-scale relief valve. Understanding when a thermal relief PSV is the right engineering solution — and when it is not — is a fundamental process safety skill.
Jose CampinsDiscuss your project with an engineer
Every article here is written by a principal consultant who works directly on projects. If any of these topics touch your scope, get in touch — we respond within one business day.