I am carrying out a quantitative risk assessment for crude oil pipeline

I don't have a feel for the values of the data describing the pipeline system below(fluid properties, operating conditions, and depth of cover) and I would appreciate any guidance on what hazards to expect following a leak or rupture of a pipeline?

Given that the the pipeline diameter and wall thickness are 0.3556 and 0.0071 m, respectively. The pipeline is laid underground and the cover depth ranges from 1.7 to 1.9 m. The operating flow rate under normal conditions is 564.4 m3/h. The crude oil is transported at 3.7 MPa and a temperature of 30 °C. The transported liquid is crude oil with a density of 880 kg/m3 (29.3 API) and a dynamic viscosity of 0.02 Pa s. The crude oil, as well as the generated vapors, are flammable. The lower and upper flammability limits are 0.9 and 7.0 (% v/v), respectively. The flashpoint is -6 °C, and the autoignition temperature ranges from 10 to 20 °C. The relative density of the vapor ranges between 3 and 5 times the density of air. Additionally, it is mentioned that the True Boiling Point (TBP) curves of this crude oil indicate that 5% of the crude is evaporated at 73 °C.

The failure can occur as a rupture or leak, and I am uncertain about the state of the fluid as it is discharged from the buried pipeline leak or rupture. Will it have enough momentum to displace the cover, which is 1.7-1.9m, causing the portion of the pipe where the rupture or leak is located to be uncovered and release the fluid outdoors? or will the fluid accumulate inside the trench of the pipe?

It is safe to say that if the fluid (gas or liquid) accumulates in the trench, it will start to diffuse to the cover. However, it wont ignite because oxygen is not present and of the properties of crude oil unless it spreads to the air.

  • $\begingroup$ And you are paid to do this assessment? $\endgroup$
    – Solar Mike
    Apr 2 at 19:15
  • $\begingroup$ No, I am a student, and I am conducting the QRA (Quantitative Risk Analysis) for a university project. The data provided for the pipeline system is derived from an online case study. mdpi.com/2227-9717/11/2/…. $\endgroup$
    – Kakashi
    Apr 2 at 19:48
  • $\begingroup$ Try grouping data and finding correlations. If you don't have data, you don't have significance, statistically. $\endgroup$
    – Abel
    Apr 4 at 3:03


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