Solid waste, for example source separated organics (SSO) or commercial and industrial (C&I) waste or both, are treated by first pressurizing the waste against a screen to produce a solids fraction and a liquid fraction. The liquid fraction can be treated in an anaerobic digester. The solids fraction is pulverized or milled, for example with a hammer mill, preferably after being diluted. The pulverized or milled waste is separated again to provide a second solids faction and a second liquid fraction. The liquid fraction can be treated in an anaerobic digester. The solids fraction is primarily inert and can be landfilled, preferably after being washed.