SEAWATER COOLING WATER SYSTEM DESIGN: BAD PRACTICE, GOOD PRACTICE

摘要

In today’s world more and more aspects of power generation, gas and oil storage and transferrnfacilities are requiring the use of large quantities of seawater for cooling and processingrnpurposes within the plant operations.rnDue to the size, location and nature of the overall development of the aforementionedrnfacilities the requirement for the cooling water system is being perceived as a non‐critical partrnof the overall scheme during the feasibility and design process.rnThe cooling water system usually comprises obtaining sea water at a certain temperature fromrnthe source, then transporting this water to the Plant process equipment by means ofrnchannels/pipelines to pumping and settling chambers on land. Once the water has been usedrnin the Plant system it then is discharged back to the sea to an environmentally designatedrndepth and location via channels or pipelines.rnThe cost of incorporating a cooling water system may only be 1 ‐ 10% of the overall cost of thernProject but the importance of providing a robust designed system that will operate the plantrnduring its design life is key to successful operation.rnOne recent example of providing cooling water to a Power Plant showed clearrnmisunderstanding of the importance of the cooling water system to overall operation of thernPlant. In fact the cooling water system was so badly designed that amongst many otherrnproblems within 3 months of commissioning the offshore pipelines were blocked by sedimentsrnand that due to this the Plant could only operate at 50% of its capacity. The reason for the poorrndesign and construction was due to the fact that the Client appeared not to understand thernimportance of the Cooling Water System and decided to conduct the design as an afterthoughtrnusing in house design team who had no experience of such systems.rnThis paper will highlight some of the problems encountered and will demonstrate the need forrnemploying at an early stage of the project experienced engineers from fields of hydraulic,rnpipeline and mechanical engineering for the successful design and then operation of a CoolingrnWater System.rnFor the reason of confidentiality the location of the project and the name of the Client cannotrnbe disclosed.