Monitoring Benzene at ppt Levels at Fencelines of Chemical Plants or Refineries

Accepted for presentation at Pittcon 2017 

Sunday March 5, 2017
McCormick Place, Chicago, IL
ACS Division of Analytical Chemistry Poster Session
Slot #38
The ACS Poster Session will be held on Sunday afternoon, March 5, 2017 in the Skyline Ballroom, West 375a, of the McCormick Place. The posters will be on display 3:30 PM to 7:30 PM with authors present from 5:30 PM to 7:30 PM.  

Authors: J.L. Maclachlan and J.N Driscoll, PID Analyzers, LLC

Title: Monitoring Benzene at ppt Levels at Fencelines of Chemical Plants or Refineries

Exposures in the area surrounding a manufacturing or chemical plant are regulated by the EPA Clean Air Act of 1990 and subsequent amendments. Since that time, more than 120 regulations have been issued. In Oct. 2015, the EPA issued a new limit of 2.8 ppb of benzene for fence lines at refineries. Fence line monitoring is important since fugitive emission sources account for most of the VOC inventory according to EPA.

Gas chromatography is one of the detection methods mentioned by EPA. The detector described by EPA is the flame ionization detector (FID). Since the FID does not detect  low ppb levels of benzene, a thermal desorber is required. The photoionization detector (PID) is 50-100 times more sensitive than the FID and does not require any support gases like H2 or zero air. The PID can detect < 1 ppb of benzene by direct injection. We have also developed a low power concentrator that can provide a 100 fold concentration of an air sample that can be desorbed in < 3 seconds. We have developed a capillary column that can separate and detect benzene specifically in under 2 minutes in the presence of 50 fold excess of other refinery hydrocarbons.  

The GC/PID will be compared with the GC/FID method for precision and accuracy of low and sub ppb levels of benzene and other VOC’s in refinery atmospheres.