Performance of a full-scale biotrickling filter treating H2S at a gas contact time of 1.6 to 2.2 seconds
✍ Scribed by Gabriel, David ;Deshusses, Marc A.
- Publisher
- American Institute of Chemical Engineers
- Year
- 2003
- Tongue
- English
- Weight
- 865 KB
- Volume
- 22
- Category
- Article
- ISSN
- 0278-4491
No coin nor oath required. For personal study only.
✦ Synopsis
Emission of objectionable odors is a majorproblem for wastewater treatment and other processing facilities. Biological treatment is a promising alternative to conventional control methods, such as chemical scrubbing, but historically, biotreatment has always required significantly larger reactor volumes than chemical scrubbers.
In this paper, we present several aspects of the operation and performance of a chemical scrubber, retrofitted to operate as a biotricklingfilter treating 16,000 m3 h-I of foul air with the original gas contact time of 1 .G to 2.2 seconds. In continuous operation f o r more than a year, the biotrickling filter has shown stable performance and robust behavior for H S treatment, with pollutant removal performance comparable to using a chemical scrubber. Reclaimed water was used as a nutrient source f o r the process, and to maintain the pH in the biotrickling filter between 1.5 and 2.2. At a gas contact time of 1.6 seconds, H$ removal was in excess of 95% for sustained inlet H$ concentrations as high as 30ppmv. This corresponds to volumetric elimination rates of 95 to 105g H$ m-3 h-l.
Efficiencies of about 90% were observed under transient conditions at 2.2 seconds gas contact time for inlet concentration peaks up to GOppm,. The biotrickling filter also removed significant amounts of reduced sulfur compounds, ammonia, and volatile organic compoundspresent in traces in the air, which is important in practical applications.
Selected eqm'ments, such as intermittent trickling operation and a one-month operation period at neutral pH, are also presented. Results indicate that the intermittent trickling operation does not have a significant eflect on H# removal. However, when operated at neutral pH, biotrickling filter performance clearly decreased, probably due to an excessive chlorine supply to the reactor through the make-up water. The study demonstrates that biotrickling filters can replace chemical scrubbers as a safer, more economical technique for odor control.