Lecture 17

Question 1

What does PIG stand for?

Answer 1

Pipeline Inspection Gauge

Question 2

How are pipelines protected externally?

Answer 2

Protective coatings
Cathodic protection with a sacrificial metal

Question 3

How are pipelines protected internally?

Answer 3

• Control of incoming solution where sulfates, organics, water, solids etc are minimized
• Physical cleaning with PIGs
• Chemical treatments like corrosion inhibitors and biocides.

Question 4

What are some limitations of PIGs?

Answer 4

They cannot clean dead legs or flow control devices.

Question 5

List some corrosion inhibitors and explain how they work.

Answer 5

Hydroxyethyl Imidazoline - has a hydrophobic aliphatic tail which forms a protective film on the metal which prevents corrosive gases from touching it.

Cl inhibitors are also looked at, however they may contribute too MIC themselves by acting as a nutrient.

Question 6

When are oxidizing biocides normally used and what are some drawbacks to them?

Answer 6

oxidizing biocides are typically inorganic and Cl or H₂O₂ based. They are highly reactive and short lived so are used to treat large volumes of water like those used for water flooding or fracking.

They do not penetrate biofilms well and are corrosive.

Question 7

What are the 3 oil sands in Alberta and how large are they? How many barrels worth of oil are we currently able to recover from there?

Answer 7

Athabasca 77,000 km²
Cold Lake 22,000 km²
Peace River 8,000 km²

170 Billion barrels