Abstract:
There is provided a process for converting wet fly ash into a useful product such as cement replacement or industrial filler. A first amount of wet fly ash is provided. The wet fly ash is fed into a mixing chamber. An amount of aggregate, such as stone, is provided. The aggregate is also fed into the mixing chamber where the wet fly ash is mixed with the aggregate. The mixed wet fly ash and aggregate is fed into a drying chamber where the mixture is heated, thereby drying the fly ash and heating the aggregate. The heated aggregate is separated from the fly ash. The heated aggregate is fed back into the mixing chamber. A second amount of wet fly ash is added to the mixing chamber where is it mixed with the heated aggregate. The heated aggregate assists in drying the second amount of wet fly ash. Once in cycle, the process is continuous. Preferably, after the dried fly ash is segregated from the heated aggregate, it is introduced to a burner where the carbon component is oxidized and the beneficated fly ash exits.
Abstract:
The present invention provides a method of beneficiating slag, including mixing the slag with water to form a slurry. The slurry is screened through a first screen to remove a first portion of material and then screened through a second screen to remove a second portion of material. In one embodiment, the second portion of material has a carbon content less than about 5% and, more preferably, a carbon content less than about 1%.
Abstract:
In the process for treating incineration residues from waste incineration plants, the incineration material is incinerated on a furnace grate. The incineration residues produced are quenched in a wet slag remover and conveyed out of the latter. The wet incineration residues which come out of the wet slag remover are firstly divided into two fractions by means of a screening operation, after which the main fraction is washed with water taken from the wet slag remover, and in the process adhering fine pieces are separated off. The washed pieces of the incineration residues are fed for reuse. The washing water together with the ultra fine pieces which have been taken up during the washing operation pass into the wet slag remover. The fine fraction produced during the mechanical separation operation is fed back to the incineration operation.
Abstract:
In a method and apparatus for processing materials comprising ashes from waste incineration plants and mineral residues to condition them in a short time by washing them and by subjecting them to electrodynamic processes and shock waves generated by high voltage spark discharges, the material is made chemically inert and aged so that it can be used immediately after treatment without harming the environment.
Abstract:
Construction material from granular material reclaimed from the ash of a municipal waste combustor wherein the ash is subjected to sorting and separating recovered metals, the granular material including particles having a maximum particle diameter of 5 to 40 mm, a U-coefficient of 10 or more, and ignition loss of 10% or less in weight and being subjected to at least one heavy metal immobilization agent, preferably phosphoric acid; and a second heavy metal immobilization agent consisting of ferrous sulfate. The ash is further subjected to drying before subjecting the ash to the at least one heavy metal immobilization agent. The ash is further subjected to mulling the material after subjecting the ash to the at least one heavy metal immobilization agent.
Abstract:
A method for treating steel works dust in order to recuperate elements capable of being upgraded. The method comprises attrition in water followed by hydraulic grading of the resulting load. The method is characterized in that is further comprises: a washing step to separate the water soluble saline fractions of the insoluble oxides; hot treatment to eliminate metals in the form of free oxides such as zinc and lead; treatment by heating at a temperature ranging between 240 and 800° C.; treatment with sulphuric acid having a concentration between 5 and 8%.
Abstract:
In order to separate a carbon-containing fraction as completely as possible from a residue, for example a pyrolysis residue, a combustible constituent is first separated from a non-combustible constituent. A carbon-containing light fraction is subsequently separated from a small-fragment fraction of the non-combustible constituent. For this purpose, in a preferred embodiment, a combination of a facility for the separation of wire with a heavy-fragment separator following the latter is provided for a continuous separation operation. The carbon-containing fraction thus obtained is preferably supplied for further utilization to a combustion chamber of a pyrolysis plant.
Abstract:
A process for removing ammonia from fly ash during processing on an inclined fluidized bed. The process begins by introducing a mixture of particulates having ammonia adsorbed therein into an inclined fluidized bed. Concurrently, a fluidizing gas is pre-heated and is also introduced into the fluidized bed. The mixture is then processed along the fluidized bed with the pre-heated fluidizing gas to achieve bubbling fluidization of the particles. This causes segregation by which a dense fraction settles downward and a light fraction rises upward in the bed. Ammonia in the particles is desorbed by the pre-heated fluidizing gas. The fluidizing gas is then scrubbed after the processing step to remove the desorbed ammonia. The process may also include the use of acoustic enhancement whereby an acoustic field is imposed on the fluidized bed to improve fluidization and segregation of the particles and to increase the efficacy of ammonia removal. In addition, a heat exchanger or electric heating elements immersed in the fluidized bed can be used to heat the ash to the temperatures needed to desorb ammonia from the ash. Furthermore, the energy efficiency of the process can be improved by recovering heat from the hot ash discharged from the fluidized bed and/or from the exhaust stream of hot fluidizing gas, for reuse during preheating steps. The improved process removes ammonia in a simple and efficient manner by preheating the fluidizing gas of the inclined bed to temperatures of 300 to 500° F., and using this preheated gas to drive off any adsorbed ammonia.
Abstract:
Object of the invention is to finely granulate the granular substances with pollutants, such as the contaminated soils and incinerated ashes, adhered and to separate the pollutants from the granular substances efficiently and further to enable the unnoxious granular substances, from which pollutants as above have been separated, to be recycled. After carrying out fine granulation of the granular substances by carrying out a coarse disintegrating treatment on the granular substances with pollutants adhered through the first fine granulation machine 21, the granular substances, which have been finely granulated by the first fine granulation machine, are subjected to, by the second fine granulation machine 22, mutual polishing among the granular substances themselves being acted by mutual rubbing forces of the substance themselves and thus the pollutants, such as heavy metals and dioxin class substances adhering strongly to the surfaces of the granular substances are separated and also the granular substances without containing the pollutants are classified from the granular substances which have already been finely granulated by the first and second fine granulation machines by the vibrational screen 30 and the classification means 50.
Abstract:
Granular substances with pollutants adhered, such as contaminated soils and incinerated ashes, are finely granulated to separate the pollutants from the granular substances efficiently and to enable the granular substances, from which pollutants have been separated, to be recycled. After fine granulation of the granular substances by a coarse disintegrating treatment through a first fine granulation machine, the granular substances, which have been finely granulated by the first fine granulation machine, are subjected to, by a second fine granulation machine, mutual polishing among the granular substances by mutual rubbing forces of the substances themselves and thus the pollutants, such as heavy metals and dioxin class substances adhering strongly to the surfaces of the granular substances, are separated, and also the granular substances not containing the pollutants are classified from the granular substances which have already been finely granulated by a vibrational screen and a classification device.