Challenge

A West Coast refinery turned to Siemens for help in providing a more consistent and reliable quality of purified boiler feedwater.  The refinery, using up to 1,500 gpm of demineralized boiler makeup water, was experiencing a variety of problems including aging demineralizers, pending environmental legislation, excessive operation costs, wide variations of raw water quality and limited capital to address these issues.

Solution

After a thorough on-site needs analysis by the local sales engineer, Siemens Water Technologies was selected to design, install and operate a 1,500-gpm mobile-based reverse osmosis (RO) system.

• Within a three-month time period, a high-purity water system was installed and put into operation feeding the refinery's existing demineralizers.
• The system consists of trailer-mounted carbon filtration, sodium softening and reverse osmosis.
• To conserve plant water and minimize waste, the RO reject water is used for cooling tower makeup.

Results

The installation of this system has provided:

• $100,000 per month reduction in the refinery's operating costs
• $50,000 per month savings in water, energy and treatment chemicals from boiler blowdown reduction
• Total new savings from the first month's operation exceeded $160,000
• Higher purity makeup water has improved waterside cleanliness, resulting in greater reliability of the boiler operation and lower maintenance costs
• Demineralizer waste volume has been reduced 93% from 750 gpm to 50 gpm resulting in lower waste treatment demand and reduced outfall