Abstract: The present disclosure relates to methods and a vehicle for enhancing the mechanical dewatering of a slurry. In one aspect, the disclosure concerns a method for enhanced dewatering of a settling pond with a mechanical dewatering vehicle including: measuring one or more properties of a slurry to be deposited in the settling pond; determining a buoyancy profile for the vehicle, based on the one or more properties measured and one or more properties of the vehicle, such that the vehicle is neutrally buoyant in the slurry when deposited in the settling pond; and determining an optimal slurry depth for the slurry to be deposited in the settling pond such that the vehicle is able to maintain substantially shear-free traction as the vehicle traverses the slurry.

Abstract: A porous particulate material for treating a fluid containing a contaminant is disclosed. The particulate material comprises a cementitious matrix or binder and treated bauxite refinery residue or red mud. At least a portion of the pores in the particulate material is open cell or interconnected pores. The invention also relates to the use of a reactive permeable barrier comprising porous material, for treating a contaminated fluid. Also disclosed is a method for producing porous particulate material for treating a contaminated fluid and a method for treating a contaminated fluid, in which the porous material is used. The invention furthermore relates to a cementitious composition comprising partially neutralised red mud and cement, wherein the partially neutralised red mud has been pre-treated by contacting it with water having a total hardness supplied by calcium, magnesium or a combination thereof, of at least 3.5 millimoles per litre calcium carbonate equivalent.