F. L. Smidth & Co., A/s

Other

Peter B Nielsen

Terkel C Christensen

A process for the removal of dissolved metals and/or metalloids from an aqueous medium having a high content of salt wherein the aqueous medium in the presence of manganese (II) ions and an oxidation agent is passed through a particulate carrier material having a specified density, initial average grain size and flow rate, so as to fluidize carrier material particles in the aqueous medium, and whereby the coated material particles thereby formed are separated from the aqueous medium.

Process for the removal of dissolved metals and/or metalloids from an aqueous medium containing same and having a high content of salt

An apparatus for burning pulverulent raw material, in particular cement raw meal to cement clinker, has a kiln (1), a cooler (2), a suspension calciner (4-12) and a multi-stage preheater (14-27). The preheater is provided with two material outlet ducts (22 and 22') directing a first stream of preheated material to a suspension burning chamber (4) with a hot air inlet (7) and a fuel inlet (5) and a second stream of preheated material to a kiln gas duct (28), respectively. Rapid quenching of kiln gas and accelerated rate of combustion in suspension calciner are provided by suspending and calcining the material in the streams in the burning chamber and the kiln gas duct, respectively, and uniting the two suspensions downstream of the suspension burning chamber (4). The calcined material is precipitated in and passed to the kiln from a precipitator (9), to which the united suspensions are directed.

Apparatus for burning pulverulent raw material

A method and an apparatus for calcining pulverulent raw material, in particular cement raw meal, wherein the material is calcined suspended in a stream of hot gas in a calcining zone (4) in an overheated atmosphere by burning fuel in a stream of oxygen-containing gas in the zone, and precipitated in a precipitation zone (9). The rate of combustion of the fuel is accelerated by maintaining a temperature within the range 900.degree.-1250.degree. C. in the calcining zone by dividing the raw material into two streams (22',22) introducing and calcining only the first stream of material (22') in the calcination chamber (4). The temperature of the hot suspension withdrawn from the calcining zone is reduced by 100.degree.-300.degree. C. to a level within the range 800.degree.-1000.degree. C. by suspending the second stream of material (22) in the hot suspension during withdrawal thereof from the calcination chamber (4) and before the calcined material is precipitated in the precipitator (9).

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Copenhagen, Denmark

Peter B Nielsen