Method for removing chlorine from fly ash

Abstract

The invention belongs to the technical field of fly ash, and particularly relates to a method for removing chlorine from fly ash. The invention provides a method for removing chlorine from fly ash. The method comprises the following steps of 1) adding fly ash, water and alkali carbonate into a stirring tank; stirring for 1-10 minutes at the temperature of 20-80 DEG C to obtain a mixture; 2) carrying out solid-liquid separation on the mixture obtained in the step 1); and 3) sending the solid obtained in the step 2) back to an original fly ash recovery system of an enterprise for recycling; andcarrying out post-treatment on the liquid obtained in the step 2). According to the method, water and alkali metal carbonate are added into the fly ash, and then solid-liquid separation is carried outthrough a filter press to obtain the dechlorinated purified ash, so that the chlorine content is greatly reduced, and the recovered alkali metal chloride can be used as industrial salt; and the resource comprehensive utilization of the fly ash without secondary pollution is realized.

Description

technical field

[0001] The application belongs to the technical field of dust removal, and in particular, the application relates to a method for removing chlorine from dust removal. Background technique

[0002] With the continuous deepening of the construction of beautiful homes with "blue sky, pure land, and green water", the internal recycling of solid waste in iron and steel enterprises has become a standard configuration for enterprises, and the recycling of dust in the factory has become inevitable. The composition of dust removal ash produced by different enterprises is different, generally containing Fe 35%-40%, Zn 3.5%-4.0%, Pb 1.5%-2.0%, Cl 1.5-2.0%. At present, the preferred method of recycling dust is high-temperature sintering, evaporation and recovery of zinc and lead powder, and the sintered agglomerate is returned to the blast furnace for smelting. Lead is a raw material in batteries, cables, bullets and ammunition, and an additive in gasoline. Because met...

Examples

Embodiment 1

[0050] A kind of method for dust removal chlorine, by weight, comprises the following steps:

[0051] 1) Add 100 parts of chlorine-containing 1.5% (mass) dedusting ash, 1900 parts of water and 5 parts of sodium carbonate into the mixing tank, and stir for 5 minutes at a temperature of 20° C. to obtain a mixture;

[0052] 2) using a fully automatic filter press to carry out solid-liquid separation of the mixture obtained in step 1);

[0053] 3) Send the solid (i.e. purified ash) obtained in step 2) back to the original dust removal ash recovery system of the enterprise for recycling; the solution obtained in step 2) is sent to the evaporation crystallizer, and the evaporated steam is condensed and then returned to the water tank. The crystallized sodium chloride is dehydrated to obtain the finished salt.

[0054] The dedusting ash is the dedusting ash in the ironmaking process.

Embodiment 2

[0056] A kind of method for dust removal chlorine, by weight, comprises the following steps:

[0057] 1) Add 20 parts of chlorine-containing 2% (mass) dedusting ash, 80 parts of water and 3 parts of sodium carbonate in a stirring tank, and stir for 5 minutes at a temperature of 50° C. to obtain a mixture;

[0058] 2) using a fully automatic filter press to carry out solid-liquid separation of the mixture obtained in step 1);

[0059] 3) Send the solid (i.e. purified ash) obtained in step 2) back to the original dust removal ash recovery system of the enterprise for recycling; the solution obtained in step 2) is sent to the evaporation crystallizer, and the evaporated steam is condensed and then returned to the water tank. The crystallized sodium chloride is dehydrated to obtain the finished salt.

[0060] The dedusting ash is the dedusting ash in the ironmaking process.

Embodiment 3

[0062] A kind of method for dust removal chlorine, by weight, comprises the following steps:

[0063] 1) Add 30 parts of chlorine-containing 2% (mass) dedusting ash, 70 parts of water and 1.5 parts of sodium carbonate into the mixing tank, and stir for 5 minutes at a temperature of 80°C to obtain mixture 1;

[0064] 2) using a fully automatic filter press to separate the mixture 1 from solid to liquid;

[0065] 3) Add mixture 1 to a stirring tank, add 70 parts of water and 1.5 parts of sodium carbonate at the same time, stir at a temperature of 80°C for 5 minutes, and obtain mixture 2;

[0066] 4) The mixture 2 is subjected to solid-liquid separation;

[0067] 5) The solid (i.e. purified ash) obtained in step 4) is returned to the original dust removal ash recovery system of the enterprise for recycling; the solution obtained in step 2) is sent to the evaporation crystallizer, and the evaporated steam is condensed and then returned to the water tank. The crystallized sodium ...

technical field

[0001] The application belongs to the technical field of dust removal, and in particular, the application relates to a method for removing chlorine from dust removal. Background technique

[0002] With the continuous deepening of the construction of beautiful homes with "blue sky, pure land, and green water", the internal recycling of solid waste in iron and steel enterprises has become a standard configuration for enterprises, and the recycling of dust in the factory has become inevitable. The composition of dust removal ash produced by different enterprises is different, generally containing Fe 35%-40%, Zn 3.5%-4.0%, Pb 1.5%-2.0%, Cl 1.5-2.0%. At present, the preferred method of recycling dust is high-temperature sintering, evaporation and recovery of zinc and lead powder, and the sintered agglomerate is returned to the blast furnace for smelting. Lead is a raw material in batteries, cables, bullets and ammunition, and an additive in gasoline. Because met...

Examples

Embodiment 1

[0050] A kind of method for dust removal chlorine, by weight, comprises the following steps:

[0051] 1) Add 100 parts of chlorine-containing 1.5% (mass) dedusting ash, 1900 parts of water and 5 parts of sodium carbonate into the mixing tank, and stir for 5 minutes at a temperature of 20° C. to obtain a mixture;

[0052] 2) using a fully automatic filter press to carry out solid-liquid separation of the mixture obtained in step 1);

[0053] 3) Send the solid (i.e. purified ash) obtained in step 2) back to the original dust removal ash recovery system of the enterprise for recycling; the solution obtained in step 2) is sent to the evaporation crystallizer, and the evaporated steam is condensed and then returned to the water tank. The crystallized sodium chloride is dehydrated to obtain the finished salt.

[0054] The dedusting ash is the dedusting ash in the ironmaking process.

Embodiment 2

[0056] A kind of method for dust removal chlorine, by weight, comprises the following steps:

[0057] 1) Add 20 parts of chlorine-containing 2% (mass) dedusting ash, 80 parts of water and 3 parts of sodium carbonate in a stirring tank, and stir for 5 minutes at a temperature of 50° C. to obtain a mixture;

[0058] 2) using a fully automatic filter press to carry out solid-liquid separation of the mixture obtained in step 1);

[0059] 3) Send the solid (i.e. purified ash) obtained in step 2) back to the original dust removal ash recovery system of the enterprise for recycling; the solution obtained in step 2) is sent to the evaporation crystallizer, and the evaporated steam is condensed and then returned to the water tank. The crystallized sodium chloride is dehydrated to obtain the finished salt.

[0060] The dedusting ash is the dedusting ash in the ironmaking process.

Embodiment 3

[0062] A kind of method for dust removal chlorine, by weight, comprises the following steps:

[0063] 1) Add 30 parts of chlorine-containing 2% (mass) dedusting ash, 70 parts of water and 1.5 parts of sodium carbonate into the mixing tank, and stir for 5 minutes at a temperature of 80°C to obtain mixture 1;

[0064] 2) using a fully automatic filter press to separate the mixture 1 from solid to liquid;

[0065] 3) Add mixture 1 to a stirring tank, add 70 parts of water and 1.5 parts of sodium carbonate at the same time, stir at a temperature of 80°C for 5 minutes, and obtain mixture 2;

[0066] 4) The mixture 2 is subjected to solid-liquid separation;

[0067] 5) The solid (i.e. purified ash) obtained in step 4) is returned to the original dust removal ash recovery system of the enterprise for recycling; the solution obtained in step 2) is sent to the evaporation crystallizer, and the evaporated steam is condensed and then returned to the water tank. The crystallized sodium ...

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