NOVELTY - A vessel component of sludge which is mixture including organic solids and water is added to sludge-shearing vessel. A substantial component of vessel component of sludge in form of bio-cellular strands and vessel-quantity of biological thickener substance are added. Thickener is mixed with water to form viscous liquid having viscosity more than viscosity of water. Vessel component of sludge and thickener are placed in vessel, to form vessel-mixture of viscous liquid, and solid material is dispersed in viscous liquid. Vessel mixture is violently sheared to liquefy sludge.    USE - Process of liquefying sludge used for fertilizer used in agricultural field (claimed).    ADVANTAGE - The method efficiently and economically liquefies sludge.    DETAILED DESCRIPTION - A sludge-shearing vessel equipped with operable shearing blades having predetermined size and robustness when operated, to shear sludge residing in the vessel is provided. A vessel component of sludge which is a mixture including organic solids and water is added to the vessel. A substantial component of the vessel component of sludge in the form of bio-cellular strands and vessel-quantity of biological thickener substance are further added to vessel. The chemical and physical characteristics of the thickener are adjusted by mixing thickener with water to form viscous liquid having viscosity more than that of water. The vessel component of sludge and the vessel-quantity of thickener are placed in the vessel, to form vessel-mixture of viscous liquid, and the solid material is dispersed in the viscous liquid. The vessel mixture is violently sheared using shearing blades with enough energy to liquefy the sludge. An INDEPENDENT CLAIM is included for process for operating abattoir.    DESCRIPTION OF DRAWING(S) - The drawing shows the schematic view explaining liquefying sludge.    Paunch-sludge receiving station (3)    Fatty waste receiving station (4)    Dehydrating station (7)    Shearing vessel (8)    Liquid sludge storage tank (12)