Semi-mechanistic modelling of ammonia absorption in an acid spray wet scrubber based on mass balance

A model to describe reactive absorption of ammonia (NH3) in an acid spray scrubber was developed as a function of the combined overall mass transfer coefficient K(y)a(v). An experimental study of NH3 absorption using 1% dilute sulphuric acid was carried out under different operating conditions. An empirical correlation for K(y)a(v) with respect to droplet Sauter mean diameter, liquid flow rate, and inlet NH3 concentration was developed with an R-2 = 97.12%. Air velocity positively correlated with K(y)a(v) at 30 ppmv, but did not exhibit an effect at higher concentrations (165-300 ppmv), while liquid flow rate showed the greatest effect on K(y)a(v). The K(y)a(v) correlation was incorporated in the performance model to construct a semi-mechanistic model with high prediction accuracy (R-2 = 97.60%, MSE = 0, RMSE = 0.03, MAPE = 5.24%). This generalised performance model can be used to predict NH3 removal efficiencies of our optimised acid spray scrubber under various operating conditions at animal facilities. (C) 2015 IAgrE. Published by Elsevier Ltd. All rights reserved.