RISK ASSESSMENT AND ECONOMIC FEASIBILITY ANALYSIS CONCERNING DEBOTTLENECKING A 50-YEAR-OLD TRANSMISSION OIL-PRODUCTS PIPELINE

Abstract

The significant drop of the Syrian crude oil production, in addition to the dramatic increase in the fuel consumption which exceeded by far the nominal capacity of the two national refineries, have made a gap between production and demand of around 3.5 million tons/year. The gap was bridged by increasing the importing rate 5% on annual basis, which means 100% in twenty years. As a result, a critical transportation problem has been raised because internal operating pressure induced by that increase exceeds the safe operation conditions of Banias-Homs pipeline, which is the only line that transport imported oil-products from Banias terminal on the Mediterranean to Homs’ storage farm.

Many scenarios have been discussed to address the problem, comprised of constructing a new pipeline, reusing an out-of-service oil pipeline, and debottlenecking the current Banias-Homs oil-products pipeline, which sounds the most applicable scenario.

The most challenging issue was that the line was made up of aged and corroded pipes made of API 5L Gr B and X48. Because the line is indispensable, it cannot be shut down for long periods of time to change the material grade. The solution was, therefore, to install an intermediate pump station within the sections where the pressure is half the maximum value. and enhance the pipeline reliability by conducting a rehabilitation plan accordingly with a condition-based integrity assessment.

The corrosion challenge was evaluated by performing an inline inspection (ILI). Consequently, a root cause analysis of pipeline degradation rates was conducted which revealed a relationship between pipeline failure and operating pressure, pipe material, topography, and water and sulfur content. Therefore, a proactive maintenance plan was developed depending on the operating parameters data and integrity assessment.

The relative risk index showed that the probability of failure could be up to 96% in the sections characterized with high population areas and harsh operating conditions. However, the implementation of the recommended risk mitigations reduced the failure probability by 30% below the calculated average.

Moreover, the Monte Carlo simulation of the worst-case scenario of the operating material throughput has shown that installing an intermediate pump station is the most feasible option in terms of capital expenditures (Capex), and operation and maintenance Cost (O & M). As a result, the operating pressure was reduced by 30%, the capacity of the line was increased by 100%, and unnecessary expense was saved on the state treasury.