Water Environment Federation (WEF) Discussion Forums / Foros de Discusión Técnica / Archives / Archived Forum Topics / Oil in water analysis / Latest PostsWater Environment Federation (WEF) Discussion ForumsWater Environment Federation (WEF) Discussion Forumshttp://www.wef.org/TechnicalDiscussions/jfuller@wef.orgSat, 06 Sep 2008 22:59:47 GMT20RE: Oil in water analysishttp://www.wef.org/TechnicalDiscussions/Topic4024-6-1.aspx<div class="Quote">We did oil in water analysis using three different methods and we got three different methods.<br><br>1. Using HACH mass spectrophotometer: 8.5 mg/l<br>2. Using gravimetric 8 mg/l<br>3 Using a combination of GC and GC MS:<br><br>C6 - C9 Fraction 28 mg/l<br>C10 - C14 Fraction 26.8 mg/l<br>C15 - C28 Fraction 11.8 mg/l<br>C29 - C36 Fraction 1.85 mg/l<br><br>Are those three different methods measured different fraction of hydrocarbon?<br><br>This is for regulatory purposes which only mention oil in water should not exceed 30 mg/l. I am confused as to what result I should present to the regulator. Also, which method is normally acceptable?</div><br>What method (if any) is specified by the regulator?<br><br>I would assume the gravimetric method to be the most appropriate. Or, at least, it's the old standby standard method. Are there really methods available using a spectrophotometer?<br><br>At the low level found, the error could easily be several mg/l no matter which method is used.Fri, 09 Feb 2007 11:33:07 GMTJeff NaumannOil in water analysishttp://www.wef.org/TechnicalDiscussions/Topic4024-6-1.aspxWe did oil in water analysis using three different methods and we got three different methods.</P><P>1. Using HACH mass spectrophotometer: 8.5 mg/l<BR>2. Using gravimetric 8 mg/l<BR>3 Using a combination of GC and GC MS:</P><P>C6 - C9 Fraction 28 mg/l<BR>C10 - C14 Fraction 26.8 mg/l <BR>C15 - C28 Fraction 11.8 mg/l<BR>C29 - C36 Fraction 1.85 mg/l</P><P>Are those three different methods measured different fraction of hydrocarbon?</P><P>This is for regulatory purposes which only mention oil in water should not exceed 30 mg/l. I am confused as to what result I should present to the regulator. Also, which method is normally acceptable?</P><P>Thank you for you help.Fri, 09 Feb 2007 00:57:39 GMTdpran