Research On The Risk Analysis Technology For A Raw Oil Booster Pump

The raw oil booster pump is one of the main equipment of residue oil hydrotreating unit. The safe and steady operation has important effect on complete equipment. Risk analysis for running pump, identification of self-fault, system cause and influence caused by malfunction are premise of pump running process monitoring, fault alarm and accident prevention and control, which can provide a reference for handling failure or accident. In order to analysis and identify the risk of raw oil booster pump, this paper synthesizes the risk analysis, fault identification, consequences and fluid mechanics simulation method, proposes and researches the risk analysis technology of raw oil booster pump. Firstly, Hazard and Operability Analysis (HAZOP) is applied to qualitatively analyze the risk of raw oil booster pump. System reasons leading to abnormal conditions, malfunction or accidents are analyzed and high-risk events and instable events of raw oil booster pump are obtained. Besides, self-fault causes are identified and failure probability is calculated. Secondly, aiming at high-risk leakage event identified by HAZOP analysis, quantitative risk analysis method is put forward to calculating pump failure rate and failure consequences. For an unstable event that pump efficiency is low identified by HAZOP analysis, the influence of rotating speed and impeller diameter on pump efficiency is studied by efficiency parameters sensitivity analysis method. The main work and conclusions are as follows:(1) HAZOP qualitative analysis has been applied to identify potential risk of equipment and evaluate risk level of causative events. As a result, high-risk leakage event and unstable event are obtained. The analysis results indicate that leakage accident and low pump efficiency are important potential risks of the process unit that contain the raw oil booster pump.(2) In allusion to quantitative risk analysis on leakage accident of the raw oil booster pump, the fault tree for leakage accident is given then transferred to Bayesian network model to quantitatively calculate the probability of the accident. To analyze the consequences model of leakage accident, the PHAST software is applied to quantitatively calculate the consequences severity of leakage accident. Considering the possibility and severity level dividing, risk matrix is constructed to conduct risk assessment for causative events of leakage accident. The analysis results indicate that improper installation or maintenance is high-risk event leading to leakage accident and the risk level of abnormal vibration, mechanical seal abnormal wear are higher than others.(3) Parametric sensitivity analysis is applied to low efficiency events. The experiment influenced by single factor and orthogonal experiment are conducted to analyze local sensitivity and global sensitivity of efficiency influence factors. The FLUENT software is used to complete design calculation and give importance degree order of efficiency influence factors. The analysis results show that the pump efficiency is significantly influenced by motor speed and medium viscosity and is less affected by impeller abrasion, medium density and outlet pressure etc.According to risk identification, risk analysis, parameter sensitivity analysis of raw oil booster pump, the accident prevention, emergency response and improving operation efficiency measures have been put forward, which has important implications for improving the efficiency of equipment safety management and ensuring to operate safely and efficiently.