Abstract: Oil spill accident is a serious emergency of offshore platform. The potential oil spill hidden danger should be eliminated in the process of platform production. An offshore platform in the Bohai Sea has two open drain sumps,collecting rain and snow water and toxic liquids containing oil and chemical agents. There is no liquid level monitoring device installed in the open drain sumps of the platform ODP design. After they are put into operation,the central control personnel cannot effectively monitor the liquid level. They can only observe the liquid level through regular inspection and start the pneumatic diaphragm pump to transfer the medium from the open drain sumps to the open drain tanks. If the liquid levels in the open drain sumps rise rapidly due to unexpected circumstances such as heavy rain,the liquid level of the equipment cannot be controlled in time,and there is a risk of oil spill into the sea. In view of this situation,the production personnel of the platform independently installed the level switches of the open drain sumps,installed the raising weir plates to prevent oil spill,carried out the double process transformation of the medium from the open drain sumps to the open drain tank and the dirty oil tank,and completed the work of changing the pump of the pneumatic diaphragm pump. The optimized process realized the timely monitoring of the liquid levels in the open drain sumps,eliminated the potential oil spill,and achieved good environmental and economic benefits.

Key words: offshore platform, open drain system, open drain sump, process transformation, oil spill risk