ICTC’s Stimulation Group is trained in formation damage mechanistic analysis, product selection and application of stimulation systems.

Keys to Recognizing Organic Precipitation

• Sudden production decline not consistent with reservoir depletion
• Visible deposits (flowlines, BHP, chokes, separators, tanks, tubing, rods, injection wells, etc.)
• Injectivity decline
• Flowlines and injection pressures increasing
• BHP observations (dynamometers,ESP power charts)
• Paraffin and asphaltene observed in offset wells

Paraffin

• Simplest form of hydrocarbon
• C16 to C60
• Crystalline deposit structure
• Soluble in crude oil
• Distinctly different than asphaltenes
• Form as a result of temperature and pressure variations
• Present throughout the oil and gas industry

Paraffin Precipitation

Paraffin is most often precipitated by a temperature change. The temperature point where the lattice of the paraffin begins to grow is called the cloud point. Once a crude oil reaches the cloud point, paraffin crystals establish a nucleation site to which more paraffin crystals will adhere. Typical causes of paraffin deposits include:

• Temperature decreases
• Pressure drop
• Light ends lost
• Existing deposits
• Asphaltenes

Asphaltene

• Aromatic/Napthenic based hydrocarbons
• Polar
• Can contain elements (O, S, N) and metals(Fe, Cu, Ni)
• Amorphous (no structure)
• Insoluble in crude oil
• Not the same as paraffin
• Present throughout the oil and gas Industry

Asphaltene Precipitation

Generally totally UNRELATED to the amount of asphaltene that is physically in the oil and is commonly motivated by:

• Reductions in temperature and pressure
• Contact with lean or rich hydrocarbon gases and CO2
• Contact with non-equilibrium oils
• Contact with various acids (pH shift)

ICTC Product Line

WC 5000* Paraffin Stimulation Solvent  Formulated to effectively deal with paraffin accumulation both in wellbores and formations.
WC 6000* Asphaltene Stimulation Solvent  Effectively deals with asphaltene accumulation both in wellbores and formations.
WC 7000* Asphaltene/Paraffin Stimulation Solvent  Effectively deals with a combination of paraffin/asphaltene or organic depositions that have deposited in wellbores and formations.
WC 9000* Asphaltene/Paraffin Stimulation Solvent Effectively deals with those solids that are a combination of paraffins/asphaltenes or organic depositions and have deposited in wellbores and formations.
* Note that all of these products have been designed with a portion of mutual solvent. This promotes more effective solvency and fines cleanup while still maintaining non-ionic properties.

 

The mutual solvent also ensures that the rock will be free of oil or hydrocarbon solvent residue thus leaving the rock water wet.

 

Stimulation Objectives

• Increased sales for the producer
• Increased profit for the producer
• Maintain an excellent success ratio
• Continue to be an industry leader
• Continue to earn industry reputation

Investigation/Approach

• What is the damage?
• How was it caused?
• Where is it located?
• How much damage is there?
• How is it affecting productivity or injectivity?

How to Select Candidates

• Sudden decline in production not consistent with reservoir depletion
• Injection decline
• Organic or inorganic deposition
• Chemical treatment history
• Acidizing history
• Questionable past solvent selection
• Production chemical (corrosion inhibitors, biocides, scale inhibitors) incompatibility
• Frequent hot oiling
• Fluctuation of fluid levels
• Plant upsets
• Review of well files
• Communication with those that are most intimate with the wells and their history

ICTC approach

• Identify the problem
• Select the right solution
• Apply the solution correctly
• Assess and evaluate results