Abstract: The invention is concerned with clarifying contaminated liquids and, in one described embodiment, contaminated liquid is continuously supplied to a first vessel, a first treatment material is intimately mixed into the contaminated liquid in the first vessel, the contaminated liquid/first treatment mixture is passed to a second vessel and a second treatment material is added to the contaminated liquid and first material mixture and intimately mixed therewith.The first treatment material preferably comprises one or more compound of the group including soluble magnesium salts, ferrous salts, manganous compounds and cuprous compounds and the second material is an alkali intended to reduce the pH of the final mixture.After the second treatment material has been added the impurities separated out from the final mixture are extracted from one outlet from the second vessel and clarified liquid is discharges from another outlet of the second vessel.

Abstract: A method of, and apparatus for, separating contaminants from a base liquid and whereby the contaminated base liquid is passed through a pretreatment vessel before being passed to a conventional separator. In one embodiment, the pretreatment vessel is of generally cylindrical form arranged with its axis substantially vertical. Base liquid to be decontaminated is supplied into the mid-height regions of the vessel through a tangential device to cause circulating flows within the vessel. The vessel includes an outlet in its top region for the release of light contaminants, an outlet in its lower region for the release of heavy contaminants and an outlet duct in its mid-region, spaced from the inlet, for releasing partially contaminated liquid from the vessel for release into a conventional separator.

Abstract: A separator for separating contaminants from a base liquid. The separator includes a roof arrangement, part of which extends downwardly and radially inwardly into the liquid in the separator. The roof arrangement is generally in inverted conical form. The decontaminated liquid flows from the separator through a flow modifying member which dampens any circulating flows in the liquid, and flows upwardly out of the separator to a reservoir defined by the inverted conical roof arrangement. The arrangement also includes structure for releasing gases from the volumes beneath the roof arrangement, thereby maintaining the whole of the roof arrangement in contact with the liquid to assist in reducing circulating flow in the liquid on the upper regions of the separator vessel.

Abstract: An aqueous composition for conditioning an aqueous system, for example a sewage slurry, comprises an alkaline earth metal hydroxide, e.g. lime, and an anionic oligomeric polyelectrolyte, e.g. a salt of polyacrylic acid which composition has at least 40% by weight of particulate solid materials. Other components may include a weighting agent, e.g. calcium carbonate, a cationic flocculant, e.g. a polyacrylamide, and a base such as sodium hydroxide.

Abstract: A method of treating water comprises adding to the water a composition comprising a weighting agent and an electrolyte having a multivalent metal cation.The resultant floc absorbs suspended solids in the water and gives rise to a dense sludge which is easily removed from the purified supernatant liquor. A composition for use in the method is also disclosed. The composition may be in the form of a slurry or a friable solid (which may be briquetted).

Abstract: Firelighter compositions comprising a hardened emulsion of a hydrocarbon oil such as kerosine in a curable resin such as a urea-formaldehyde resin and having distributed uniformly throughout a particulate solid fuel of particle size distribution such that the preponderance is retained on a sieve of mesh number 35, nominal aperture size 0.44 mm.