DE2027365B2 - Hot-gas purifier using pocket-type filter - with precooler to prevent damage to filter materials - Google Patents

Abstract

The pre-cooler and filter units are enclosed in a common enclosed space into which the cooling air, derived partially from within that same enclosed space and partially from the outside, warmed in the cooler is released being in turn released to atmos. via throttled adjustable outlets. A part of the efflux of warmed air from the cooler may also be released direct to the atmos. The temp. of this efflux is above the dew point of any aerosols or Cl, S or F cpds. in the smoke gases esp. from metallurgical smelters which are fed into the plant. Reduced corrosion of metal parts of filter and enclosure.

Description

3 4

With this solution it is possible to use the room temperature line? with regulating flap la from a valve

temperature of the dust gas filter and the cooler absorbing gate 8 is conveyed into the cooler, in the heat exhaust

changing building or room and thus the interior exchange to a temperature of around 100 to 120 ° C

The walls of the filter housing and cooler are cooled to a temperature required for the filter material in the dust gas fil above the dew point of the aerosols 5 ter is permissible. The cooled flue gases flow

or salt compounds of the cooler and the filter via a connection 9 in the filter 1 and become

Bring flue gas flowing through. It is via a suction fan 10 and a pipe 11 as

the cooler is blown out according to the following three aspects - clean gas is blown into the open, while the impurities

placed: the flue gases are retained by the filter

a) The smoke gases are released to ^{10 te} " ^will * \ _ .., _. _1ΛΛΟ ^

ζ B 120 ° C cooled down ^{The S1C in the} cooler 5 is heated to around 100 ° C

Cooling air is supplied via a connection 12 or a nozzle in

b) for cooling the fresh air, return air, or the, the filter 1 and the radiator used 5 containing mixture of fresh air and return air, space 2 blown and is provided via a connecting piece 13 of which ensure that the temperature in the ₁₅ space 2 removed , the cooling air inlet area of the cooler flowing through the room 2 at least _men d _e amount of cooling air either through the throttle 7 a is so high that here, too, at no point at the _{m of} the supply line 7 or a throttle 13 α in the Abdem flue gas facing surfaces to damage air line 13 is adjustable. The cooling air heats the leading condensation phenomena occur room 2, so that the inner walls of the can. _ao cooler and the filter housing 1 this temperature

c) The exiting from the cooler, by accepting heat, which is above the dew point of the exchanged heated cooling air is used to remove aerosols and chemical compounds that come into contact with flue gases, but not 40 to 50 ° C if possible to exceed the cooler and filter on its side facing the to the commission of the room still allow 2 facing to the flue-gas side to a temperature ^a control 5 of the bag filter. It is important to keep a door that does not allow condensation to form. ^is also that the entering into the condenser cooling air Optionally not mixing with increasing below, Sonderen above the dew point additionally introduced fresh air ensured ^de r od aerosols. like. lies. It is therefore so vorgegandaß the ambient temperature in the filter and g ^en > that the cooling air as a mixture of outside air and cooler area, especially in zones that enter the building for the 3 ° air from building room 2 into the cooler, are only intended to enter the building - The air intake 7 is held so high within the Raurade that the desired ^m es 2 still achieved with a suction effect (corrosion protection) opening into the room 2, but the connector 14 with the regulating flap 14 α for hot air to pass through the system is not seen impossible, so that the proportions of cold and warm air is made. 35 can be regulated by adjusting the two throttles 7 α and 14 α.

According to the German patent specification 767 029 it is understandable that the air exiting the cooler 5 from the nozzle is known to purify dust gases by centrifugal separator 12 in the space 2, which naturally with gases at any level above 40 to 50 ° C (dew point) is, ago temperature can be charged, the 40 and generally at about 100 ° C, so that the walls of the centrifugal separator the combustion temperature in room 2 despite any heat losses in a separator receiving air above a Temperature could be that heat a BeKammer, so that this heated air to go to room 2 by operating the filter relief of an air heater as a combustion air system no longer allows. To now room temperatures can be fed to a boiler. Such a 45 above 40 to 50 ° C, especially in the on-site possibility, is to be avoided in the filter system of the invention rich of the Raunes2, cannot be used in the room 2, because the hot flue gases from fresh air via a nozzle 15 with a regulating flap smelting furnace or the like. must first be fed to a temperature 15 α and fan 16, which are also cooled down, which mixes for the filter bags or the warm air from the cooler and the Tempe filter hoses are harmless. 50 ratur z. B. to 40 to 50 ° C reduced. To do one

The drawing shows an embodiment of the sufficient distribution of the heated, from the Filter system according to the invention for hot flue gases cooler 5 and the air exiting through the Stutin schematic representation. zen 15 blown outside air over the entire

A per se known or customary dust gas filter to reach space 2 is a channel on the connector 13

z. B. a bag filter or pocket filter 1, its 55 17 with regulating flaps 17 a distributed over the height

Filter surfaces by purge air and, if necessary, provided. One can also proceed in such a way that the

In addition, a vibrating device is used to clean the outlet connection 12 of the cooler with one to the outside

the, is in an enclosed space 2 underpassing branch connections and a control element verse

Bracht, which is hen through its own building or in one, so that only part of the heated cooling air

existing building by erecting sides 60 in the room 2 and the remaining part in the open air

walls 3 and a ceiling 4 is made. The Ta- will. This also makes it possible to adjust the temperature in the

interim filter 1 is an air cooler 5 for the clean-up room 2 to reduce to a value that is just

the hot flue gases from metallurgical furnaces, e.g. B. can still achieve the desired corrosion protection

an aluminum remelting furnace, connected upstream, which and at the same time the accessibility of the plant to the

is arranged in the same room 2. Allowed the cooler 5 65 for eligible locations. Next is

the hot flue gases from the furnace can be accessed via a walk-through area of room 2

Feed line 6 is supplied, and these hot flue gases are protected against higher temperatures by separating aprons.

are in the cooler through outside air, which is to be built in via a screen or deflection surface

which the inspection area is protected. The various measures mentioned above can be used can also be used in combination.

By designing the filter system according to the invention, condensation will in any case be formed on the inner walls of the filter housing and cooler avoided, with the heating of the the Filtei and the cooler receiving space in a simple manner: by the heated cooling air of the upstream th flue gas cooler is reached.

1 sheet of drawings

Claims (7)

1 require 2 hep effort. In these electrical patent claims, the following can also be found in the following: Corrosion trofilter due to acids that are formed even in the presence of small amounts of water vapor 1. Plant for cleaning off hot smoke or aerosols or the like contained in the smoke gas, in particular from metallurgical furnaces, but this is at least partially lower Use of a dust gas filter with filter tabs that can be used with higher temperatures see or filter hoses and with upstream work is carried out. Washout filters are already in tem air cooler, through which the temperature of the trial, but which use water, so that hardly hot flue gases are reduced to a temperature. Corrosion due to the formation of acids can be avoided that can affect the filter surfaces of the pocket, apart from the fact that the washer filter is contaminated is harmless and therefore has to be clarified or discharged into water, shows that the filter (!) and the cooler (5) lead to higher expenditures or to Gewässerverin a closed space (2) arranged impurities leads. are, in which the cooler (5) leaving it. On the other hand, it is known that dust gas filters with warmed cooling air escapes freely and from which there are 15 filter bags or filter bags even with the finest Dust with an extremely high degree of cleaning via a controllable extraction line (17, 13) flows. relatively cheap investment outlay 2. Plant according to claim 1, characterized and that filter materials are available today draws that the cooling air of the cooler (5) are part, z. B. Needle felts, which are cleaned with a high level of cleaning the outside air and partly the closed 20 degrees can withstand temperatures of up to about 180 ° C. It is nen space (2) is removed. known such dust gas filter for cleaning 3. System according to claim 1 or 2, characterized by using hot flue gases by the indicates that the air cooler (S) of the hot filter is connected to a cooler through which the smoke-flue gases is designed so that the temperature gas temperature to a temperature of z. B. 100 to the 25 entering the closed space (2) is cooled down to 120 ° C. This cooled smoke-air From the cooler (5) above the dew point gases are then discharged through the dust gas filter aerosols contained in the smoke gases or not. Since the aerochlorine contained in the flue gases, Sulfur and fluorine compounds. brines and chemical compounds have a dew point 4. Plant according to one of claims 1 to 3, below 40 to about 80 ° C, it is characterized in that the pocket filter 30 of the temperature of the flowmenter through the pocket filter (1) and the cooler (S) Closed hot gases are possible to achieve a dry separation of the space (2) through the connections from the cooler (5), thus preventing the cooling air from attacking a temperature of about filter surfaces by the acids formed 40 to 50 ° C is heated. can be. 5. System according to one of claims 1 to 4, 35 It has now been found in practice, characterized in that in the Entnahmelei- that, since the dust gas filter systems with cooler often device (13) of the cooling air from the closed outdoors or be installed in cold buildings, room (2) an adjustable throttle (13 ä) is built into the outer walls of the filter housing and cooler. on an annual average at an outside temperature 6. Plant according to one of claims 1 to 5, 40 door of about 15 ° C and thereby in colder years characterized in that the times from the cooler are far below. These temperatures lie- (5) exiting, heated cooling air immediately below the dew point of the aerosols and the at the outlet connection (12) of the cooler, some of the connections in question in the flue gases can be regulated, so that is wisely directed into the open. due to the temperature gradient on the inside 7. Plant according to one of claims 1 to 6, 45 of the walls of the filter housing and the cooler characterized in that in the region of the condensates are formed by their salt content to operate the filter system - acid, sulfuric acid and fluoric acid the walls attack the part of the closed space (2) separating the housing and cause corrosion and scuffing or deflecting surfaces lead to the protection against interference. It has been shown that even with the heated cooling exiting the cooler so use of very expensive insulation thermal bridges air are arranged. not at certain points or only through additional ones high effort can be avoided, so that often in individual particularly endangered areas Corrosion damage cannot be prevented.
55 The object of the invention is therefore to The invention relates to a system for corrosion and destruction of the housing walls-Abreinigen hot flue gases, in particular from a metallurgical furnace with filter bags or filter hoses, using a dust-armed dust gas filter system and a hot gas filter with filter bags or filter hoses and flue gas on one for the filter bags or filters with an upstream air cooler, through which the temperature of the flue gases, which depresses the temperature of the flue gases, can be avoided in a simple manner,
is pressed, which is harmless to the filter surfaces. This object is achieved according to the invention It is known that hot flue gases from metallur- solved that in the above-mentioned system for Chemical furnaces, e.g. aluminum remelting furnaces, cleaning of hot flue gases from the filter and the Aerosols and / or chlorine, fluorine and sulfur coolers 65 arranged in a closed room contain bonds, so that you are for cleaning, in which the heated leaving the cooler of these flue gases in general previously electrostatic precipitator cooling air escapes freely and from which it is reused via a which work perfectly, but flows off a hoopable extraction line.