A modular system and method for producing urea from bio-mass includes means and steps for “homogenizing” a biomass feedstock stream having components with different bulk density BTU content into a stream having a consistent bulk density BTU content. The steps include cleaning the incoming bio-mass feedstock stream to remove non-organic matter, blending the cleaned bio-mass feedstock stream to obtain a homogeneous blend having a consistent bulk density BTU content, and milling the homogeneous blend bio-mass feedstock stream to a predetermined size no greater than 12 mm.