WIT Press

Design, testing and evaluation of prototype biofilter to mitigate odor in tunnel-vent poultry production system


Free (open access)


Volume 12 (2017), Issue 7



Page Range

1223 - 1232

Paper DOI



WIT Press




Industrial farm animals such as broilers housed in large tunnel-vent poultry system provide for a protein source of close to 100 million Filipinos. An efficient animal production facility, tunnel-vent system operates on a Climate Controlled System (CCS) which is controlled by a central computer. However, in the Philippines, there were recorded evidences of system malfunction and failure posing a great public concern due to obnoxious gases which inevitably attract household flies flocking nearby communities.

This research delved on an in-depth study on the mechanism of operations of a tunnel-vent poultry production system in the northeastern part of the Philippines and used the baseline data to design, test and evaluate a prototype biofilter to mitigate odor as the gist of the study.

The designed simple, low-cost and environment-friendly prototype biofilter is made up of locally available materials. It is composed of a plenum, an exhaust fan and a supporting structure. The plenum is subdivided into four (4) drawers separated by screens to house filter media. Series of drawers was conceived in anticipation of choice and density of biomass filter materials. The exhaust fan which is 30.48 cm (12-in ø) operates on a suction mechanism which guides and pushes the air to pass through the filter media by as much as 230 cfm. The supporting structure provides for stability and protection of the biofilter and the exhaust fan.

Performance evaluation showed positive and promising result. Thus, further study on upscaling and field testing of the biofilterin actual tunnel-vent system for odor mitigation is necessary.


ammonia, biofilter, biofiltration, filter media, gas reduction efficiency, hydrogen sulfide, mechanically decorticated coco coir, odor mitigation, tunnel-vent poultry system