The rise in atmospheric pollution caused by gases such as ammonia has led many researchers to conduct studies aimed at decreasing or treating the emissions of such pollution gases. The control of ammonia emission is important for public health and environmental protection. Beside conventional technologies such adsorption, scrubbing, condensation, and chemical oxidation for treating odor gases, biofiltration has been emerging as a new technology over the past three decades. It is known as having a low capital and operating cost, low energy requirement and the absence of residual products for fuurther treatment or disposal especially when applied to dilute and easily biodegradable waste gases under performance of biological methods for treatment of a wide range of organic and inorganic compounds has been proven recently. However, the performance of conventional biofiltration system may unstable when the influent concentration of pollutant fluctuates.

  In this study, we investigated and evaluated the adsorption capability of three inorganic materials Bio-coal, Granular Activated Carbon (GAC), and Mobile Crystalline Material-41 (MCM-41) with batch tests and column test. The results showed that MCM-41 has an outstanding advantage adsorption of ammonia compared to the other two materials. Therefore, this material has a high potential to prevent shock loading and recover non-loading periods for a biofiltration system. Base upon these results, we have developed a hybrid biofiltration system for ammonia removal in polluted air stream. MCM-41 was used as packing material for the buffer column of this system. The results showed that MCM-41 played an important role to reduce the fluctuation of influent concentration and normalize influent concentration of ammonia. As a consequence, the performance of the hybrid biofiltration system is more stable than one of a conventional biofiltration i.e., without any pre-treatment.

  Accroding to our experiments, mathematical modeling was conducted in order to fit the experimental results. And base on the fitting curves, several important parameters of the models were estimated. The results of mathematical modeling enable us to predict the responses of both conventional biofiltration system and hybrid biofiltration system in specific conditions. This may help to design upscale systems.

Keywords : Ammonia, MCM 41, GAC, Bio-coal, buffer column, and hybrid biofiltration