This research will address some of the fundamental issues involved in the simulation of LNG spill and dispersion from an LNG tanker. The model will consider heat and mass transfer including the hydrodynamics of the individual fluids and the mixed dispersed phase via a three dimensional CFD model. The vapour concentration, peak concentration, maximum flammability limit and effects of dispersion phenomenology on the lower flammability limit will be studied by analyzing the volume fraction composition, temperature distribution and the velocity distributions of the dispersed phase. The second aspect of the research focuses on modelling study on the gasification of bio-oil and bioslurry in fluidized bed reactor. The model takes into account the reactions, mass and heat transfer, hydrodynamics as well as evaporation of the feed droplets and interactions of the three phases by a three-dimensional CFD model. The product gas composition, gas and particle temperatures will be computed.