CONOCOPHILLIPS RESPONSE TO THE SATURATE GAS PLANT FIRE AND EXPLOSION INCIDENT

摘要

The ConocoPhillips Humber Refinery was first commissioned in 1969. Over subsequent years it has been expanded and its efficiency enhanced. One project was the addition of a Saturate Gas Plant (SGP), designed to improve the recovery of Liquefied Petroleum Gas (propane and butane) and gasolene (petrol components). The SGP was commissioned in 1980. The design included facilities to water wash the feed streams in order to remove inorganic salts which could ultimately cause corrosion and contamination of the products. Soon after commissioning additional water wash was installed in the overhead system, downstream of two main fractionator water draw streams. The additional water wash was designed to flush out soluble deposits which were causing a blockage in the overhead system, these deposits being mainly hydrates. It was not intended to reduce corrosion. These deposits were not totally unexpected. In April 2001 the 6" pipe between the de-ethaniser and the overhead condensers X452/3 failed downstream of the additional overhead system water wash, releasing highly flammable materials which ignited causing significant plant damage. Following the incident ConocoPhillips carried out a Root cause Analysis. The HSE investigation resulted in an Improvement Notice. These are described in the paper and focused on Piping Inspection (Root Based Inspection), Corrosion Management and Management of Change (MOC). ConocoPhillips believed that these actions were the start point. Additional longer term actions are also described in the paper. The Saturate Gas Plant was rebuilt to current design standards and the overheads system water injection was relocated between the two overheads heat exchangers. The paper describes the monitoring that was initiated and proposed long term plans. These additional steps are an essential part of the requirements to comply with Regulation 4 of COMAH. This being achieved by the implementation of a comprehensive Risk Based Inspection process that includes input from inspection, corrosion engineers and operating staff. This process starts at the initial review developing inspection plans, inspection results and a re-evaluation of the original review conclusions.