Understanding Waxes- The impact of their precipitation and deposition on hydrocarbon rheology and flow

This unique theoretical and practical course is offered jointly by PCT and KAT and will be held at ours laboratory facilities in Cornwall, England, UK.

The theory: practical split will be roughly 40:60 with hands-on laboratory tests and practical exercises to complement the taught theoretical knowledge ensuring that attendees are well-prepared to tackle real-world scenarios.

WAXES:

Waxes are a natural constituent of crude oils and gas condensates consisting of mainly heavier (>C17) paraffinic hydrocarbons. These may be straight, branched chain or cyclic, and can have a significant impact on production

Wax Appearance Temperature – Delegates will gain hands-on experience of determining the WAT/WDT for a series of different example test fluids, and a practical understanding of the importance of sub-sampling a test fluid correctly to ensure a representative sample.

RHEOLOGY:

The presence of wax crystals can have an adverse effect on the rheological properties of the fluid. This has important implication to pipelines, either in-field or export as they can impart non-Newtonian behaviour, i.e. that the viscosity of the oil depends, in addition to the temperature, upon the shear rates applied to it. A good common example of this is household non-drip paint. Here, under low shear the paint does not flow (i.e. non-drip), but at high shear when applied by paintbrush, the paint flows naturally to cover the surface. Such behaviour in production operations normally manifests itself during shut-downs or later in field life when production rates drop off. Following a shut-in, when flow restarts, the initial shear rates may be very low. At low shear rates the apparent viscosity may be high, in some cases so high that the available pressure from the pumps is insufficient to start flow. This is particularly a problem in subsea lines where the fluid temperature falls, compounding the high viscosity.

Pour Point – Delegates will run manual pour points, in accordance with the industry standard ASTM / IP methodology, for a number of different example test fluids, and gain a practical understanding of how the fluid rheology is affected by past thermal and shear history.

Yield Stress – Delegates will gain a practical experience of both techniques using KAT’s Brookfield Rheometers and 15m model pipelines, an understanding of how the results from each can be scaled to full size pipeline, plus their differences and limitations.

Viscosity – Delegates will gain practical experience of operating KAT’s series of Brookfield Digital Portable Viscometers to determine dynamic viscosity vs. temperature curves for different example test fluids to simulate a range of steady state flow conditions while the test fluid is cooled from above the wax appearance temperature to a minimum temperature.

DEPOSITION:

In addition to affecting the flow properties of a crude oil, wax can also be deposited. This can occur if the internal surface of the pipeline falls below the wax appearance temperature of the crude, i.e. the temperature at which wax crystals first start to form. Wax can accumulate on the pipewall and, if left untreated, builds-up into a wax layer. This increases the surface roughness at the pipe wall and leads to an increase in frictional pressure drop across the pipeline when the fluids are in turbulent flow (as is the case under normal operating conditions). The wax layers can also reduce the effective cross sectional area of the pipe causing a loss in throughput in systems which are pressure limited

Wax Deposition Flow Loop & Coaxial Shear Cell – Delegates will receive practical demonstrations of KAT’s deposition flow loop and coaxial shear cell used to assess wax deposition under representative field conditions.

Wax Deposition Cold Finger – Delegates will gain practical experience of the stirred cold finger tests that KAT employs for the rapid screening of inhibitors. The test equipment comprises of cooled stainless-steel tubes or plates, each immersed in separate stirred samples of test fluid. Tests are allowed to run for a pre-determined optimum duration after which time the cold fingers / plates are removed and digital images of any deposits formed recorded. A written description of the deposits, their tenacity, weight, and the levels of entrained fluid are also noted.

PLEASE NOTE:
The Delegate Rate includes hotel accommodation for three nights, all meals and transportation from the hotel to KAT’s laboratories for the practical session. The theoretical sessions will be held at the hotel.

COURSE SCHEDULE:

Evening Before
Delegates Arrive. Check-in.
Networking Evening Meal – Meet your fellow
Delegates and the Trainers

Days 1 & 2
Breakfast
9 a.m. – 12 p.m.     Theoretical Session
12 p.m. – 1 p.m.      Lunch
1 p.m. – 1.30 p.m.  Transfer to KAT
1.30 p.m. – 4 p.m.  Practical Session
4 p.m. – 4.30 p.m.  Return Transfer to Hotel
Evening Meal

Day 3
Breakfast. Check-out.
9 a.m. – 9.30 a.m.   Transfer to KAT
9.30 a.m. – 12 p.m.  Final Practical Session
Delegates Leave

Places are very limited and will be allocated on a “first come, first served” basis. For more information and to register interest in attending, please email: susan.caddell@prodchemtraining.com or phone: +44 (0)7340476232

YOU WILL LEARN ABOUT:

• Theoretical training in waxes, rheology and deposition
• Practical hands-on sessions for determining WAT/WDT, Yield Stress, Viscosity and more
• In-depth understanding of how wax influences fluid behavior under varying conditions
• Utilisation of cutting-edge equipment for predicting and managing wax deposition
• Insights into chemical additive screening to control wax deposition and improve operational efficiency
• Expert guidance and mentorship from experienced oilfield chemistry Subject Matter Experts

WHO SHOULD ATTEND?

• Any engineer or operations/production technician
• Laboratory Technicians
• New Graduate Chemists
• Account Managers

ABOUT THE TRAINERS:

• PCT Technical Director, Stephen Heath is a Production Chemist with more than 34 years of experience in the industry. He has been delivering specialist production chemistry courses for many years in Europe and the Middle East.
• KAT Managing Director, Dr Neil Chilcott has 25 years of experience in oil and gas related to flow assurance, production chemistry, and project management.

Both are globally recognised experts in their fields.