摘要:
A method of treating solid-containing material contained in or produced from an effluent or waste from a process for the treating of waste paper. The solid-containing material includes constituents of the waste paper and organic material including cellulose fibers and inorganic particulate material including calcium carbonate and other inorganic particulate material included in the waste paper. The solid-containing material is subjected to a heat treatment that incinerates the organic material present and forms from the inorganic particulate material present a calcined product including calcium oxide from thermal decomposition of calcium carbonate. The calcined product is formed into an aqueous suspension wherein calcium oxide is converted to calcium hydroxide. The calcined product in the suspension is comminuted and a reagent is added to the suspension to form a salt-forming anionic species to form an insoluble calcium salt precipitate mixed or aggregated with other inorganic particulate material derived from the waste paper constituents.
摘要:
A method of treating solid containing material derived from effluent or sludge from a plant for deinking paper, the material containing calcium in the form of one or more insoluble calcium compounds, the method including the steps of treating the material with an acid to cause dissolution of the calcium thereby forming a calcium ion-containing solution in which insoluble solids are suspended, separating the solution from the insoluble solids and incinerating the separated solids. The solution containing calcium ions may be treated by adding one or more reagents to form a calcium compound precipitate, eg calcium carbonate. The particulate solids produced following the incineration step and following the precipitate formation may be employed as pigments or fillers in paper making or paper coating.
摘要:
A method of treating solid containing material derived from effluent or sludge from a plant for de-inking paper, the material containing calcium in the form of one or more insoluble calcium compounds, the method including the steps of treating the material with an acid to cause dissolution of the calcium thereby forming a calcium ion-containing solution in which insoluble solids are suspended, separating the solution from the insoluble solids and incinerating the separated solids. The solution containing calcium ions may be treated by adding one or more reagents to form a calcium compound precipitate, eg calcium carbonate. The particulate solids produced following the incineration step and following the precipitate formation may be employed as pigments or fillers in paper making or paper coating.
摘要:
The present invention describes clear coating compositions comprising a particulate inorganic mineral, wherein the d50 of the particulate inorganic mineral is less than about 1 μm, and wherein the mineral includes a kandite clay.
摘要:
A weighting agent for use in a wellbore fluid composition is provided. The weighting agent includes a ferrosilicon material, wherein iron is present in the ferrosilicon material in an amount equal to or greater than about 50% by weight of the ferrosilicon material. A composition including a wellbore fluid and a weighting agent, as well as methods for using and making a weighting agent, are also provided.
摘要:
A new composite material which is useful as a pigment in paper making or paper coating is produced by precipitating a white insoluble pigment compound, eg calcium carbonate, in an aqueous suspension containing a mixture of fine particulate material eg titanium dioxide particles and fibers, eg cellulosic fibers. These suspended solids in the mixture are derived from separate stocks and added together to produce the composite pigment material. The new material is a bonded matrix of the fibers and the white pigment compound having particles of the fine particulate material, eg TiO2, dispersed and bonded within the matrix. The new material may exist in the form of particles in dry or wet form which may be further treated in a known way prior to use in paper making or paper coating. Use of the new material allows expensive fine particulate material such as TiO2 particles to be better retained in a paper making composition whilst at the same time avoiding the known problem of agglomeration or ‘crowding’ of the fine particles which is known to affect adversely the optical properties of the composition produced using the fine particles.
摘要:
A process for recovering inorganic material from an effluent suspension produced in the treatment of waste paper. The effluent suspension, in the form of an aqueous suspension containing at least 2% by weight of dry solids, is contacted with an oxygen-containing gas at an elevated temperature, and at an elevated pressure sufficient to keep the water component of the sludge in the liquid phase, for a time sufficient to effect substantially complete oxidation of the organic material in the suspension. The resulting product is dewatered and then resuspended in water, whereafter there is separated from the suspension water containing fine carbon particles in suspension to leave the desired inorganic material.
摘要:
The present invention describes clear coating compositions comprising a particulate inorganic mineral, wherein the d50 of the particulate inorganic mineral is less than about 1 μm, and wherein the mineral includes a kandite clay.
摘要:
A method is described for the treatment of a solid containing material obtained from effluent from an industrial plant or process, eg. a plant for the de-inking of waste paper. Such effluent comprises an aqueous suspension of solids comprising organic material and inorganic particulate material. The inorganic particulate material contains a substantial amount of calcium carbonate and is likely also to contain kaolin or metakaolin. The solids may also contain carbon particles. The method includes subjecting the solid containing material to a heat treatment process such that the temperature is controlled to be maintained in the range 600.degree. C. to 800.degree. C. preferably 600.degree. C. to 750.degree. C., to cause burning of the organic material without decomposition of more than about 50% by weight, preferably not more than about 10% by weight, of the calcium carbonate present to produce a particulate calcium carbonate-containing inorganic material substantially free of organic material. The particulate product is preferably white and useful as a pigment or filler material, eg. in paper making.