The operator of the Trans Mountain Expansion (TMX) pipeline plans to amend certain quality rules for heavy crude from September 1 after complaints from shippers and buyers of oil on the system that began service in May.
Besides quality changes, the operator Trans Mountain Pipeline has replaced its Low TAN Dilbit (LTD) crude pool with Pacific Cold Lake (PCL) crude pool. PCL will contain bitumen diluted with crude having a density less than 800 kg/m3, according to a filing with Canadian Energy Regulator (CER).
As for quality changes, the vapor pressure limit at 37.8 Celsius (100F) for heavy crudes – PCL, Pacific Dilbit and Synbit – will shift to <= 70kPa (kilopascals) during May 1-November 30; for December 1-April 30, that limit will be <=76kPa. Presently, the vapor pressure limit for all petroleum types on TMX is at 103 kPa.
Limits for TAN (Total Acid Number) for PCL crude will be <=1.1mg KOH/g while that for Pacific Dilbit >1.1mg KOH/g. Currently, TMX accepts PCL oil (formerly Low TAN Dilbit) with TAN at <1.3 mg KOH/g, and Pacific Dilbit at >1.3mg KOH/g.
In recent months, multiple companies including Canadian Natural Resources (CNRL), ConocoPhillips, Valero Energy, and Chevron, have raised concerns over the existing standards for TAN and vapor pressure specifically for heavy crude oil moving on TMX. CNRL pointed out that vapor pressure limits would incentivize blending “low-value” light ends into components of a heavy crude pool, and negatively impact its sale price. Valero had said the limit won’t be suited for supply into the U.S. West Coast markets.
