Abstract: In accordance with the present invention, there is provided a calcium removal method capable of reducing operation cost. A solution L2 containing potassium or/and sodium, and calcium is passed through an ion-exchange resin 35 to separate the solution into a solution containing potassium or/and the sodium, and a solution containing calcium. Operation cost can remarkably be decreased since potassium carbonate is not required to remove calcium as before. Timing for changing a calcium-containing water L3 and a salt water L4 discharged from the ion-exchange resin can be performed based on at least one measurement result selected from the group consisting of: a calcium or chlorine concentration; electrical conductivity; and pH of a fluid which is discharged from said ion-exchange resin. The solution may be a filtrate L1 that is obtained by washing a chlorine bypass dust D generated in a cement burning process, or a leachate W of a final disposal site 50.

Abstract: To minimize harmful effects on operation due to scale adhesion while accommodating increase in the amount of generated chlorine bypass dust and suppress facility cost and running cost including medical agent cost low when incineration ash and dust contained in extracted cement kiln combustion gas are subject to water treatment. [Means for Solving Problems] A water treatment system 1 comprising: a dissolution tank 32 for dissolving a fly ash A in a water W; a dissolution tank 22 for dissolving a dust D contained in combustion gas extracted from a kiln exhaust gas passage running from an inlet end of a cement kiln to a bottom cyclone in a water W; and a vertical filter press 11 for separately filtering a slurry S2 fed from the dissolution tank 32 and a slurry S1 fed from the dissolution tank 22 from each other.

Abstract: To provide a low price industrial salt by reducing facility and operation costs without electro-deposition and crystallization and through reduction in quantity of chemicals used. An industrial salt S obtained by the steps of: extracting a part of combustion gas from a kiln exhaust gas passage running from an inlet end 12b of a cement kiln 12 to a bottom cyclone 13; recovering dust D from the extracted gas G2 and washing recovered dust; and drying a filtrate L1 after the washing in a gas stream. The industrial salt can be obtained by removing a calcium component from the filtrate and drying the filtrate from which the calcium component is removed in a gas stream. Further, from the filtrate can be removed sulfate radical, and drying the filtrate from which the calcium component is removed in a gas stream to obtain the industrial salt. For the drying can be used an exhaust gas discharged from a clinker cooler 12a and a spray drier 43 may be used for the drying.

Abstract: In accordance with the present invention, there is provided a calcium removal method capable of reducing operation cost. A solution L2 containing potassium or/and sodium, and calcium is passed through an ion-exchange resin 35 to separate the solution into a solution containing potassium or/and the sodium, and a solution containing calcium. Operation cost can remarkably be decreased since potassium carbonate is not required to remove calcium as before. Timing for changing a calcium-containing water L3 and a salt water L4 discharged from the ion-exchange resin can be performed based on at least one measurement result selected from the group consisting of: a calcium or chlorine concentration; electrical conductivity; and pH of a fluid which is discharged from said ion-exchange resin. The solution may be a filtrate L1 that is obtained by washing a chlorine bypass dust D generated in a cement burning process, or a leachate W of a final disposal site 50.

Abstract: To minimize harmful effects on operation due to scale adhesion while accommodating increase in the amount of generated chlorine bypass dust and suppress facility cost and running cost including medical agent cost low when incineration ash and dust contained in extracted cement kiln combustion gas are subject to water treatment. [Means for Solving Problems] A water treatment system 1 comprising: a dissolution tank 32 for dissolving a fly ash A in a water W; a dissolution tank 22 for dissolving a dust D contained in combustion gas extracted from a kiln exhaust gas passage running from an inlet end of a cement kiln to a bottom cyclone in a water W; and a vertical filter press 11 for separately filtering a slurry S2 fed from the dissolution tank 32 and a slurry S1 fed from the dissolution tank 22 from each other.

Abstract: To provide a low price industrial salt by reducing facility and operation costs without electro-deposition and crystallization and through reduction in quantity of chemicals used. An industrial salt S obtained by the steps of: extracting a part of combustion gas from a kiln exhaust gas passage running from an inlet end 12b of a cement kiln 12 to a bottom cyclone 13; recovering dust D from the extracted gas G2 and washing recovered dust; and drying a filtrate L1 after the washing in a gas stream. The industrial salt can be obtained by removing a calcium component from the filtrate and drying the filtrate from which the calcium component is removed in a gas stream. Further, from the filtrate can be removed sulfate radical, and drying the filtrate from which the calcium component is removed in a gas stream to obtain the industrial salt. For the drying can be used an exhaust gas discharged from a clinker cooler 12a and a spray drier 43 may be used for the drying.

Abstract: A molding of calcium silicate having high strength, which is similar to a natural timber, wherein tobermorite, C--S--H (Calcium Silicate hydrate) and quartz are mixed, and glass fiber and pulp are added, respectively, and a Ti/Qi peak ratio of which is powder X-ray diffracted is 0.1 to 1.0, and an absolute bulk density of the molding is 0.3 to 0.7 g/cc.