US5018457A — Waste treatment system

Claim 1

Independent Claim 172 words

A method of processing hazardous waste comprising the steps of: a) incinerating the hazardous waste to a temperature sufficient to break down the hazardous waste; b) collecting the solids produced by the incineration step; c) directing at least a portion of the exhaust gas stream produced by the incineration step through a spray dryer; d) passing all of the gas stream from the incineration step including that portion exiting the spray dryer through a scrubbing and absorbing device to remove particulates and acid gas from the gas stream by contacting the gas stream with a scrubbing and acid gas absorbing slurry or solution; e) separating a portion of the scrubbing and acid gas slurry or solution liquid after contact with the gas stream as a waste liquor; f) spraying the waste liquor into the exhaust gas stream passing through the spray dryer to evaporate the water in said waste liquor and produce a dry residue; and g) collecting the dry residue so that there is no liquid waste output from the system.

Claim 2

Independent Claim 172 words

A method of processing hazardous waste comprising the steps of: a) incinerating the hazardous waste to a temperature sufficient to break down the hazardous waste; b) collecting the solids produced by the incineration step; c) directing at least a portion of the exhaust gas stream produced by the incineration step through a spray dryer; d) passing all of the gas stream from the incineration step including that portion exiting the spray dryer through a scrubbing and absorbing device to remove particulates and acid gas from the gas stream by contacting the gas stream with a scrubbing and acid gas absorbing slurry or solution; e) separating a portion of the scrubbing and acid gas slurry or solution liquid after contact with the gas stream as a waste liquor; f) spraying the waste liquor into the exhaust gas stream passing through the spray dryer to evaporate the water in said waste liquor and produce a dry residue; and g) collecting the dry residue so that there is no liquid waste output from the system.

Claim 3

Independent Claim 190 words

A system for processing hazardous waste comprising: incinerator means for incinerating the hazardous waste to a sufficient temperature to break down the hazardous waste, and produce an exhaust gas output; spray dryer means operatively communicating with said incinerator means to receive at least a portion of the exhaust gas output from said incinerator means, said spray dryer means including spray means for spraying a slurry into the exhaust gas stream to cause water in the slurry to be evaporated and pass out of said spray dryer means with the gas stream; scrubber means adapted to receive the gas stream output from said incinerator means including that from said spray dryer means; said scrubber means including a scrubbing slurry or solution and contacting means adapted to contact the gas stream in said scrubber means with said scrubbing liquid to clean same; and supply means for supplying a portion of said scrubbing slurry or solution from said scrubber means to said spray means in said spray dryer means to spray said waste liquor into the exhaust gas stream to evaporate the water from said waste liquor leaving a dry residue for collection.

Claim 4

Independent Claim 190 words

A system for processing hazardous waste comprising: incinerator means for incinerating the hazardous waste to a sufficient temperature to break down the hazardous waste, and produce an exhaust gas output; spray dryer means operatively communicating with said incinerator means to receive at least a portion of the exhaust gas output from said incinerator means, said spray dryer means including spray means for spraying a slurry into the exhaust gas stream to cause water in the slurry to be evaporated and pass out of said spray dryer means with the gas stream; scrubber means adapted to receive the gas stream output from said incinerator means including that from said spray dryer means; said scrubber means including a scrubbing slurry or solution and contacting means adapted to contact the gas stream in said scrubber means with said scrubbing liquid to clean same; and supply means for supplying a portion of said scrubbing slurry or solution from said scrubber means to said spray means in said spray dryer means to spray said waste liquor into the exhaust gas stream to evaporate the water from said waste liquor leaving a dry residue for collection.

Claim 5

Dependent Claim 17 words

The method of claim 1 wherein step d) includes passing the gas stream through a venturi scrubber.

Claim 6

Dependent Claim 27 words

The method of claim 3 wherein step b) further includes passing the gas stream through an absorber to further absorb any acid gas in the gas stream.

Claim 7

Dependent Claim 36 words

The method of claim 1 further including the step of passing the gas stream through a heat exchanger in heat exchange with combustion air to cool the gas stream after step c) and before step d).

Claim 8

Dependent Claim 21 words

The method of claim 5 further including the step of passing the gas stream through a mist eliminator after step d).

Claim 9

Dependent Claim 23 words

The method of claim 6 further including passing the gas stream through a filter to remove submicron particulate matter from the gas stream.

Claim 10

Dependent Claim 30 words

The method of claim 1 further including the step of passing the gas stream through a separator device between steps a) and c) to remove solids from the gas stream.

Claim 11

Independent Claim 128 words

A method of removing particulates from a heated gas stream comprising the steps of: a) passing at least a portion of the gas stream through a sprayer dryer; b) passing the gas stream through a heat exchanger to further cool the gas stream c) subsequently passing the gas through a gas scrubbing device while exposing the gas stream to a scrubbing solution or slurry to clean the gas stream; d) removing a portion of the scrubbing solution or slurry from the scrubbing device as waste liquor; and e) spraying the scrubber waste liquor into the gas stream passing through the spray dryer to cause the gas stream to evaporate the water in the scrubber waste liquor leaving a dry residue for collection while simultaneously cooling the gas stream.

Claim 12

Independent Claim 128 words

A method of removing particulates from a heated gas stream comprising the steps of: a) passing at least a portion of the gas stream through a sprayer dryer; b) passing the gas stream through a heat exchanger to further cool the gas stream c) subsequently passing the gas through a gas scrubbing device while exposing the gas stream to a scrubbing solution or slurry to clean the gas stream; d) removing a portion of the scrubbing solution or slurry from the scrubbing device as waste liquor; and e) spraying the scrubber waste liquor into the gas stream passing through the spray dryer to cause the gas stream to evaporate the water in the scrubber waste liquor leaving a dry residue for collection while simultaneously cooling the gas stream.

Claim 13

Independent Claim 150 words

A method of removing particulates from a gas stream with a temperature of about 1800-2500° F. (982-1371° C.) comprising the steps of: a) passing at least a portion of the gas stream through a spray dryer; b) subsequently passing the gas stream through a gas scrubbing device while exposing the gas stream to a scrubbing solution or slurry to clean the gas stream; c) removing a portion of the scrubbing solution or slurry from the scrubbing device as waste liquor; and d) spraying the scrubber waste liquor into the gas stream passing through the spray dryer to cause the gas stream to evaporate the water in the scrubber waste liquor leaving a dry residue for collection while simultaneously cooling the gas stream to reduce the gas stream temperature about 1200-1900° F. (641-1038° C.) in the spray dryer as a result of spraying the scrubber waste liquor into the gas stream.

Claim 14

Independent Claim 150 words

A method of removing particulates from a gas stream with a temperature of about 1800-2500° F. (982-1371° C.) comprising the steps of: a) passing at least a portion of the gas stream through a spray dryer; b) subsequently passing the gas stream through a gas scrubbing device while exposing the gas stream to a scrubbing solution or slurry to clean the gas stream; c) removing a portion of the scrubbing solution or slurry from the scrubbing device as waste liquor; and d) spraying the scrubber waste liquor into the gas stream passing through the spray dryer to cause the gas stream to evaporate the water in the scrubber waste liquor leaving a dry residue for collection while simultaneously cooling the gas stream to reduce the gas stream temperature about 1200-1900° F. (641-1038° C.) in the spray dryer as a result of spraying the scrubber waste liquor into the gas stream.

Claim 15

Dependent Claim 33 words

The method of claim 3 wherein step d) includes exposing the gas stream to a scrubbing liquid selected from the group comprising sodium hydroxide, sodium carbonate, potassium hydroxide, magnesium hydroxide and calcium hydroxide.

Claim 16

Independent Claim 141 words

A method of removing particulates from a heated gas stream comprising the steps of: a) passing at least a portion of the gas stream through a spray dryer; b) subsequently passing the gas stream through a gas scrubbing device while exposing the gas stream to a scrubbing solution or slurry to clean the gas stream and passing the gas stream through an absorber to further absorb any acid gas in the gas stream; c) passing the gas stream through a mist eliminator; d) removing a portion of the scrubbing solution or slurry from the scrubbing device as waste liquor; and e) spraying the scrubber waste liquor into the gas stream passing through the spray dryer to cause the gas stream to evaporate the water in the scrubber waste liquor leaving a dry residue for collection while simultaneously cooling the gas stream.

Claim 17

Independent Claim 141 words

A method of removing particulates from a heated gas stream comprising the steps of: a) passing at least a portion of the gas stream through a spray dryer; b) subsequently passing the gas stream through a gas scrubbing device while exposing the gas stream to a scrubbing solution or slurry to clean the gas stream and passing the gas stream through an absorber to further absorb any acid gas in the gas stream; c) passing the gas stream through a mist eliminator; d) removing a portion of the scrubbing solution or slurry from the scrubbing device as waste liquor; and e) spraying the scrubber waste liquor into the gas stream passing through the spray dryer to cause the gas stream to evaporate the water in the scrubber waste liquor leaving a dry residue for collection while simultaneously cooling the gas stream.

Claim 18

Dependent Claim 45 words

The method of claim 1 wherein step a) includes raising the temperature of the gases to a temperature of about 1800-2500° F. (982-1371° C.) and wherein step c) includes cooling the exhaust gas stream to a temperature of about 400-500° F. (204-260° C.) or less.

Claim 19

Dependent Claim 17 words

The method of claim 1 wherein step d) includes passing the gas stream through a venturi scrubber.

Claim 20

Dependent Claim 33 words

The method of claim 14 wherein step d) further includes passing the gas stream through an absorber after passage through said venturi scrubber to further absorb any acid gas in the gas stream.

Claim 21

Dependent Claim 21 words

The method of claim 15 further including the step of passing the gas stream through a mist eliminator after step d).

Claim 22

Dependent Claim 37 words

The method of claim 16 further including the step of passing the gas stream through a heat exchanger in heat exchange with a second fluid stream to further cool the gas stream between steps c) and d).

Claim 23

Dependent Claim 30 words

The method of claim 17 further including the step of passing the gas stream through a filter after step e) to remove additional submicron particulate matter from the gas stream.

Claim 24

Dependent Claim 58 words

The method of claim 18 further including the steps of discharging the gas stream out of a stack after passage through the filter and injecting at least a portion of the second air stream heated in said heat exchanger in the gas stream in the stack to minimize the visible water vapor plume in the discharging gas stream.

Claim 25

Dependent Claim 22 words

The system of claim 2 wherein said scrubber means includes a venturi scrubber for contacting the gas stream with said scrubbing liquid.

Claim 26

Dependent Claim 39 words

The system of claim 20 wherein said scrubber means further includes an absorber downstream of said venturi scrubber to contact said scrubbing slurry or solution with the gas stream to further absorb any acid gas in the gas stream.

Claim 27

Dependent Claim 35 words

The system of claim 21 further including a mist eliminator down stream of said absorber through which the gas stream from said absorber passes to remove liquid and solid particulate matter from the gas stream.

Claim 28

Dependent Claim 42 words

The system of claim 22 further including a heat exchanger located between and communicating with said spray dryer and said venturi scrubber for placing the gas stream in a heat exchange relation with a second fluid stream to cool the gas stream.

Claim 29

Dependent Claim 62 words

The system of claim 23 further including a stack through which the gas stream is discharged after passage through said mist eliminator and means for mixing at least a portion of the heated second fluid stream from said heat exchanger with the gas stream in said stack to minimize the visible water vapor plume in the gas stream discharging from said stack.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1994-05-27	1994-11-26	1995-05-28	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1998-05-27	1998-11-26	1999-05-28	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2002-05-27	2002-11-26	2003-05-28	$7700.00	Window Closed / Lapsed

Waste treatment system

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