초록 ▼

Particulate material for use in waste water treatment. The material comprises granules of a plastic material (e.g. poly-ethylene), each of which contains a plurality of grains of a substantially inert mineral (e.g. sand) coated thereon to provide a habitat for microorganisms effective in waste water

Particulate material for use in waste water treatment. The material comprises granules of a plastic material (e.g. poly-ethylene), each of which contains a plurality of grains of a substantially inert mineral (e.g. sand) coated thereon to provide a habitat for microorganisms effective in waste water treatment. The granules will have a predetermined particle size which is governed by the particle size range of the granules, e.g 3-10 mm and the grains will have a predetermined particle size range, e.g. 0.1-3.5 mm.

대표청구항 ▼

[ We claim:] [1.] A method for preparing particulate material for use in waste water treatment comprising the steps of:a) contacting granules of plastics material with a mixture of grains of a substantially inert material and grains of a substance soluble in a solvent which does not affect the plast

[ We claim:] [1.] A method for preparing particulate material for use in waste water treatment comprising the steps of:a) contacting granules of plastics material with a mixture of grains of a substantially inert material and grains of a substance soluble in a solvent which does not affect the plastics material or the substantially inert material at an elevated temperature, to coat the granules with the mixture; andb) subsequently contacting the coated granules with a solvent to dissolve the substance soluble in said solvent from the coating to provide granules coated with said grains of the substantially inert material in a predetermined packing density range.