A portable processing plant for processing granular material is provided. The portable plant includes a plurality of portable processing modules configured to be stacked vertically to allow for a vertically downward progression of the generally granular material through the portable processing plant. Each portable processing module includes a self-supporting independent frame structure and has at least one processing component affixed to the self-supporting independent frame structure. The self-supporting independent frame structures of the plurality of portable processing modules combine to define a structural skeleton of the portable processing plant. Each self-supporting independent frame structure can be removed from the structural skeleton substantially fully assembled while the at least one processing component carried by the self-supporting. Methods of assembling and disassembling the portable processing plant are also provided.
