Challenge

A West Coast refinery turned to Siemens for help to provide 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