NOVELTY - System for removing water from sludge comprising: depositing a semi-solid sludge cake and a dewatering agent in a mixing device; mixing the sludge and the dewatering agent having a porous structure in a weight ratio of the sludge to the dewatering agent of 1:1-10:1; and compressing the sludge and the dewatering agent to release moisture, is claimed.    USE - The system and methods are useful for removing water from sludge, where the semi-solid sludge cake comprises: at least one of sludge in connection with the processing of peat harvesting, human waste, animal waste, aluminum, ferries, pharmaceutical products, chemical products, semiconductor products, drugs and foods, sewage sludge, oil sludge, water purification sludge, animal slurry sludge, fruit waste sludge, fresh peat sludge, milled peat sludge, paper sludge, de-inking sludge, paper fibers sludge or recycled nappy waste sludge; or at least one of sewage sludge, pharmaceutical sludge, dairy sludge, food processing sludge, oil sludge, water purification sludge, animal slurry sludge, fruit waste sludge, fresh peat sludge, milled peat sludge, paper sludge, deinking sludge, paper fibers sludge or recycled nappy waste sludge. The dewatering agent comprises at least one of milled rice husks, milled nut shells, milled corn cob, milled palm fronds, milled bamboo, milled strand board, milled wood or milled polyethylene powder (preferred) (all claimed).    ADVANTAGE - The methods: provide the separated semisolid sludge cake, which is converted to form a solid material adapted for use as fuel, and the dewatering agent, which can be re-used; minimize the possibility of and/or prevents the particles from collapsing under the pressure exerted during compression; provide improved de-moisturization and improved dewatering; and are environmentally friendly, as the methods allow for the reuse of recovered polyethylene for many times, and enable recycle and/or produce less material needing disposal.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for:    (1) improved waste treatment method (I) for removing water from sludge, comprising: (a) dewatering (102) the sludge comprising an output from a wastewater treatment system to form the semi-solid sludge cake; (b) dispensing (104) the semi-solid sludge cake in a hopper and dispensing the dewatering agent in a recipient dewatering agent hopper; (c) depositing (106) the semi-solid sludge cake and the dewatering agent in a mixing device; (d) mixing (108) the semi-solid sludge cake and the dewatering agent; and (e) compressing (110) the semi-solid sludge cake and the dewatering agent to release moisture; and    (2) improved waste treatment method (II) for removing water from sludge, comprising: steps (a)-(c) as above per se; (d1) mixing the semi-solid sludge cake and the dewatering agent (having a porous structure in at least one of: a weight ratio of the semi-solid sludge cake to the dewatering agent of 1:1 and 10:1, when the dewatering agent comprises polyethylene powder; and a weight ratio of the semi-solid sludge cake to the dewatering agent of 10:1, when the dewatering agent comprises at least one of milled rice husks, milled nut shell, milled corn cob, milled palm fronds, milled bamboo, milled strand board, milled wood or a milled strand board) in a mixing device; and step (e1) compressing the semi-solid sludge cake and the dewatering agent to release moisture forming a compressed material.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic flow diagram of the improved waste treatment method for removing water using the system.    Dewatering (102)    Dispensing (104)    Depositing (106)    Mixing (108)    Compressing (110)