Submitted to: BARC Poster Day
Publication Type: Abstract Only
Publication Acceptance Date: April 25, 2001
Publication Date: N/A
Interpretive Summary: The burning issues of odors coming out of various sources will continue to be a major concern in the future. With increasing quantity of biosoilds, or animal or swine manure, stricter regulations, and intensifying public demands regarding the associated short-term nuisance and long-term health issues, the control of odors has become the most problematic issue facing the treatment facilities. Unfortunately, the technology to reliably and objectively analyze odorous gases is not available. The current research was initiated to develop a handy method to characterize and quantify odorous gases from various sources, e.g., wastewater, compost, and animal or swine manures and their treatment facilities. Initially, trimethylamine, carbon disulfide, dimethyl sulfide, dimethyl disulfide, and propionic and butyric acids were selected as target compounds. The developed method can be quantify the odorous gases even at tens pptv level. Since the new method does not require extensive sample extraction step and can be performed within a short time frame, it can help many researchers to exam the odor characteristics of various sources. Potentially, the proposed method also can be incorporated into an on-line odor monitoring system. In fact, control strategies of reducing odors from unit processes in a wastewater or animal/swine manure treatment facility will be studied with this new analytical method.
Technical Abstract: Odors are rated as a primary concern of the public and are considered in design and operation of wastewater, or animal or swine manure treatment facilities. In order to improve odor quality of a process, the following studies should be performed; 1) the odor development through the retention time of each process, 2) the odor characteristics of feed to each process and its final product, and 3) the relationship between odors from the process and process conditions. However, due to the lack of analytical technology that is reliable, and non-human sensory dependent, research on odors is at a preliminary stage. SPME (solid phase microextraction) utilizes a small, coated fiber that equilibrates with the gas phase prior to direct analysis by GC. A method to easily analyze odorous gases was developed using SPME fibers and a gas generator coupled to a permeation devices. The method has been applied to quantify the odorous compounds (trimethylamine, carbon disulfide, dimethyl sulfide, dimethyl disulfide, propionic acid, and butyric acid) in the headspace over wastewater, thickened sludge, and biosolids collected from unit processes at a local wastewater treatment plant. The method also has been applied to verify the relationship between odors from thickened sludge and the process condition, e.g., pH and ORP. In the future study, the method will be extended to incorporate more compounds such as mercaptanes, more acids, and cresol. Then, the method will be applied to characterize odors from composting processes, and animal and swine manure treatment processes. Also, it will be utilized to develop control strategies for reducing odors from unit processes (especially, thickeners and digesters) at wastewater treatment plants.