Slugcatcher: Treatment and reuse of wastewater during cleaning

Challenge:
The slugcatcher at a Gas Terminal required cleaning after several years without any extensive maintenance. Little was known of the type and amount of pollution. The customer’s request was to treat the expected waste water and recycle the effluent in order to avoid the need to dispose of it off site. By returning the water that was used for cleaning back into the jetting unit the customer created a closed loop system, avoiding the cost and environmental impact of additional water.

Solution:  
United Rentals supplied an integrated treatment solution to remove the pollution within the Slugcatcher and enable the reuse of water using the following 6 steps:

• Removal of large solids >3.5mm with Bag Filters used as strainers.
• Treatment of Hydrocarbon Vapours using our Gas Scrubber.
• Separation and removal of floating pollution with a Filtration “Open Top” Tank equipped with an under- run weir and an Oil Skimmer.
• Separation of settling solids via another Filtration”Open Top” Tank with over-run and an Air Operated Pump to transfer the settled solids to the dewatering solution.
• Filtration of the suspended solids down to 1 micron through several filtration steps using multiple Bag Filters (50, 10, 1 micron), thereby ensuring high pressure pumps and nozzles would not be adversely affected by small pollutants.
• Dewatering of the settled solids with Dewatering Boxes, making the external disposal of solids easier and less expensive.

Benefits: 
Thanks to the United Rentals integrated solution, our customer benefited from significant cost savings by utilising fresh water and minimising disposal of liquid and solid waste, which meant they were able to control costs. Our customer could enjoy peace of mind knowing they had a single point of contact for technical support and through the delivery of exceptional health & safety and equipment use training.

.