A method and a corresponding plant for denitrifying bypass exhaust gases in a cement clinker production plant. Raw meal is sintered in a rotary kiln and deacidified in a calciner. A rotary kiln inlet chamber is connected to the calciner directly or by a riser duct. Bypass exhaust gas is drawn off near the inlet chamber. This exhaust gas is guided into a first mixing chamber, in which the exhaust gas is cooled to between 800 and 950 C., then the exhaust gas is guided through a reaction pipeline segment, wherein the dwell time is between 0.5 and 3 seconds and ammonia, aqueous ammonia solution, or ammonia-releasing substances are injected for denitrification. Then the exhaust gas is guided into a second mixing chamber, in which the exhaust gas is cooled to between 150 to 250 C. Then the exhaust gas is guided to a filter for dust removal.

A method and a corresponding plant for denitrifying bypass exhaust gases in a cement clinker production plant. Raw meal is sintered in a rotary kiln and deacidified in a calciner. A rotary kiln inlet chamber is connected to the calciner directly or by a riser duct. Bypass exhaust gas is drawn off near the inlet chamber. This exhaust gas is guided into a first mixing chamber, in which the exhaust gas is cooled to between 800 and 950 degrees C., then the exhaust gas is guided through a reaction pipeline segment, wherein the dwell time is between 0.5 and 3 seconds and ammonia, aqueous ammonia solution, or ammonia-releasing substances are injected for denitrification. Then the exhaust gas is guided into a second mixing chamber, in which the exhaust gas is cooled to between 150 250 degrees C. Then the exhaust gas is guided to a filter for dust removal.

The present disclosure provides a method for recycling soil contaminated with mercury and dioxin. The method includes: desorbing mercury and dioxin from the contaminated soil by an indirect rotary furnace; condensing the mercury and discharging it by a condensing and discharging unit; and a secondary indirect burner for decomposing dioxin at a high temperature, so as for the concentration of the contaminants in the exhaust being examined to meet regulation standards and the treated soil to meet the current regulations. The present disclosure also provides an apparatus for recycling contaminated soil containing mercury and dioxin.

The present disclosure provides a method for recycling soil contaminated with mercury and dioxin. The method includes: desorbing mercury and dioxin from the contaminated soil by an indirect rotary furnace; condensing the mercury and discharging it by a condensing and discharging unit; and a secondary indirect burner for decomposing dioxin at a high temperature, so as for the concentration of the contaminants in the exhaust being examined to meet regulation standards and the treated soil to meet the current regulations. The present disclosure also provides an apparatus for recycling contaminated soil containing mercury and dioxin.

A method and a corresponding plant for denitrifying bypass exhaust gases in a cement clinker production plant. Raw meal is sintered in a rotary kiln and deacidified in a calciner. A rotary kiln inlet chamber is connected to the calciner directly or by a riser duct. Bypass exhaust gas is drawn off near the inlet chamber. This exhaust gas is guided into a first mixing chamber, in which the exhaust gas is cooled to between 800 and 950 degrees C., then the exhaust gas is guided through a reaction pipeline segment, wherein the dwell time is between 0.5 and 3 seconds and ammonia, aqueous ammonia solution, or ammonia-releasing substances are injected for denitrification. Then the exhaust gas is guided into a second mixing chamber, in which the exhaust gas is cooled to between 150 250 degrees C. Then the exhaust gas is guided to a filter for dust removal.

A rotary kiln for sintering raw material powder includes a sintering device provided with a tube assembly configured to mix the raw material powder and a heating assembly configured to heat the raw material powder that is mixed by the tube assembly. Moreover, the rotary kiln includes a supply device provided with a supply assembly inserted into one end of the tube assembly to supply the raw material powder into the tube assembly and a collecting assembly provided on one end of the tube assembly to collect a gas and vapor, which are generated while heating the raw material powder. Additionally, the rotary kiln includes a condensing device configured to condense the vapor collected in the collecting assembly to liquefy the vapor into a liquid state. As a result, the vapor generated in the tube assembly may be smoothly removed.