Odor Control with Guaranteed Performance – Interview with Centriair

Resource Recovery, Technology and Innovation
Anders Wistrom of Centriair will be presenting a session on Odor Control at the Biosolids and Renewable Energy Technology Seminar next month. He answered some questions for us on the subject and says most of the odor work is “proprietary” and not readily available and, when available, often not very useful for the design or operation of odor control facilities.

What are the challenges your clients face when dealing with Odor Control?

Odor issues are often addressed on a case-by-case basis when nuisances occur.  The biggest challenge is that most facility owners are not aware that there are robust tools available to set enforceable performance standards for odor control equipment.  However, robust tools are available to set quantitative odor criteria, implement odor testing protocols and air dispersion modeling specifically designed for odor.  Hence, impacts and compliance at sensitive points of reception can readily be assessed and quantified.

What kind of research goes is done to find a solution?

I can only report on the work that I am familiar with.  For example, academic research is conducted at several universities and agencies in the US on toxic air emissions (for example work conducted by EPA to control emissions from coal fired power plants).  With respect to odor control relatively little has been published.  Most of the odor work is “proprietary” and not readily available and, when available, often not very useful for the design or operation of odor control facilities.

However, there are a number of articles written about the implementation of EN13725, which is the European olfactory standard.  EN 13725 is very much the global standard for the testing of odors and the basis for rational design, facility operation and compliance monitoring.

Are there different techniques/processes when working with odor from wastewater compared to another industry?

The short answer is yes.   Odors are typically a concoction of a myriad of volatile and semi-volatile organic and inorganic compounds having a wide variety of chemical characteristics.  The key factor for successful odor control is to understand the odor profile – the type and concentration of different odorants that make up the foul air.  This is where some understanding of the chemistry becomes important because you want to match the odor technology with the odorant chemistry such that you can pick the best technology and do the job as efficiently and cost effectively as possible. 

For example, ammonia is not effectively removed by UV Oxidation, instead a water based scrubber would be a better technology for this application.  Another example are odors “clinging” to oil droplets – from making french fries, chicken nuggets, and fried noodles – which require a particle separation step to remove droplets down to one micron in size before odor control can be even be addresse

What are the regulations of odor for a treatment plant in California?

Regulations in California for odor control are typically local, generic and qualitative driven in most part by nuisance complaints or during the development phase.  For example consider the following:

Odor control facilities shall be provided for xx and yy when located within 1/2 mile of residential or commercial areas.  The reviewing authority should be contacted for design and air pollution control objectives to be met for various types of odor control units.

There is a trend towards some waste management agencies adopting EN13725 (the European olfactory standard) as an odor measurement tool for monitoring and compliance.  But so far, the California AQMDs have not established quantitative odor emission standards, which do little to alleviate concerns expressed by facility owners and the public.   


Be sure to catch Anders Wistrom’s discussion: Trust, but Verify – Odor Control with Guaranteed Performance on November 14 in Berkeley or November 15 in Irvine at the Biosolids and Renewable Energy Technology Seminar.