Cement kiln dust treatment system and method
AssigneeMercutek LLC
InventorsPeter D'Amico, Christopher Poling, Thomas Lesniak
Life of this patent
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Abstract
A method for treating cement kiln dust is provided. The method includes the steps of receiving cement kiln dust (CKD) from a kiln; heating the collected CKD; forming a gas stream of vaporized metal and CKD by sufficient heating to separate at least one heavy metal from the collected CKD stream to create a cleaned CKD stream and a metal stream; providing a water soluble alkaline-earth metal polysulfide; combining the heavy metal stream with the water soluble alkaline-earth metal sulfide to create a combined stream; and removing at least a portion of one heavy metal from the combined stream.
Claims19
A method for treating cement kiln dust, comprising:
- receiving cement kiln dust from a cement kiln;
- heating the cement kiln dust to separate at least one heavy metal from the cement kiln dust to create a heavy metal containing gas stream;
- treating the heavy metal gas stream with a treating fluid, wherein treating the gas stream with the treating fluid comprises treating the gas stream with a treating fluid containing at least one alkaline-earth metal sulfide;
- and
- removing at least a portion of at least one heavy metal from the gas stream.
A system for treating cement kiln dust, comprising:
- a volatilization vessel;
- at least one heat source configured to heat a cement kiln dust stream within the volatilization vessel forming a gas stream containing at least one metal;
- a treating chamber in communication with the volatilization vessel;
- a treating fluid containing at least one alkaline-earth metal sulfide;
- and
- at least one nozzle within the treating chamber configured to spray the gas stream with the treating fluid separating at least a portion of the at least one metal from the gas stream.
A method for removing mercury from cement kiln dust, comprising:
- collecting cement kiln dust from a cement kiln;
- heating the collected cement kiln dust to a temperature at least as high as the volatilization point of mercury to form a stream of volatilized mercury and a stream of modified cement kiln dust;
- separating the stream of modified cement kiln dust for further use;
- treating the stream of volatized mercury with a treating fluid containing at least one alkaline-earth metal sulfide to form a particulate containing the mercury;
- and
- collecting the particulate for subsequent handling.
Dependencies are inferred from the claim text.