Challenge 

Pacific Northwest customer need to take a >200′ D sour crude tank filled with several feet of sludge out of service. The sludge was to be processed via centrifuge in a location adjacent to a heavily used toll bridge. However, odor complaints from toll booth operators had the potential to result in customer having to pay daily bridge tolls for every car taking the bridge in by the local Air Quality jurisdiction . Bridge traffic is estimated at >40,000 cars per day. The potential  of an approximate $5 per car penalty fee, totaling nearly $200,000 a day, is an unacceptable result of this needed service. Envent Corporation was tasked with creating a robust vapor control solution ensuring compliance and eliminate the possibility of ANY odor complaints.

Solution 

Envent provided a three phase Permitted vapor control solution. The first phase of vapor control was implemented to manage vapors off the large diameter tank while in the initial degassing phase. Envent’s system was comprised of a recirculating scrubber (for H2S removal), along with a high flow thermal oxidizer. Phase two of vapor control consisted of redundant liquid / carbon / blower system which was manifolded to Permitted temporary tanks, mix tanks, centrifuge and associated hooch. Phase three of vapor control was to maintain a vacuum on the fixed tank as sludge was being removed with manways open after tank was degassed. Envent provided high flow vapor conveyance lines, 5,000 CFM blower and 5,000 CFM high flow carbon trailer.

Benefit

Envent Corporation provided the customer with a vapor control solution which managed to safely eliminate nuisance odors to the surrounding community as well as maintain 100% compliance, resulting in no fines.