A novel parallel computational fluid dynamic (CFD) code based on method of lines (MOL) approach was developed for the numerical simulation of multi-component reacting flows using detailed transport and thermodynamic models. The code was applied to the prediction of a confined axi-symmetric laminar co-flowing methane-air diffusion flame for which experimental data were available in the literature. 1-, 5-and 10-step reduced finite-rate reaction mechanisms were employed for methane-air combustion sub-model. Steady-state velocity, temperature and species profiles obtained by all the mechanisms were validated against experimental data and were found to be in reasonably good agreement with measurements. The code was found to be a useful tool for the prediction and understanding of transient combustion systems.