Technical Bulletin No. 0945: Adsorbable Organic Halide (AOX) Analytical Method Performance at Bleached Papergrade Sulfite Mills and Findings of an AOX Source Investigation

A study was conducted to understand causes of and develop potential solutions to analytical problems associated with analysis of wastewaters from bleached papergrade sulfite mills for adsorbable organic halide (AOX). Column plugging and excessive AOX breakthrough from the first carbon column to the second column are common analytical problems reported on wastewater samples from totally chlorine free (TCF) sulfite mills. Results using a pre-column affixed with a Cerafelt® plug in the lower end to capture solids showed that contributions of AOX from solids were minimal in process sewer samples evaluated in this study, suggesting that excluding solids from sample analyses would bias AOX results low by less than 5%.