Method and system for purifying fiber-resin emissions

A method and apparatus for purifying waste product emissions from the manufacture of glass fiber products, including a system in which an electrostatic precipitation may or may not be employed, and in which separate, and easily controlled, forming air and oven air scrubbing systems are employed.

This invention relates generally to the art of regulating and purifying the 
emission of chemical waste products into the atmosphere, and is especially 
adaptable for use in purifying waste product emissions associated with the 
manufacture of fiber glass insulation. The invention, however, is 
applicable to any manufacturing process involving the purification of 
gaseous, liquid and solid waste. 
BACKGROUND OF THE INVENTION 
Purifying emissions of chemical waste, such as fiber resins and other 
pollutants from fiber glass insulation manufacturing facilities, is an 
increasingly difficult problem. Strict environmental standards and the 
need to operate such facilities at a continuous and efficient level of 
production have given rise to a need for a safe, highly efficient, and 
reliable system for purifying emissions. 
The variety of apparatus and systems currently available do not 
economically provide for the purification of emissions at environmentally 
acceptable levels. In addition, none of the apparatus and systems found in 
the prior art and in current technology has been able to eliminate 
effectively the inherent safety dangers and operating problems caused by 
the accumulation of particulate matter in the purification system. These 
accumulations are especially dangerous in exhaust ducts leading from 
high-temperature manufacturing operations where they pose serious fire 
hazards. The accumulations also hinder the overall effectiveness of the 
purification system by lowering its efficiency and requiring it and the 
fiber glass insulation manufacturing operation to be shut-down for 
periodic cleaning. 
Accordingly, it is a primary object of the invention to provide a process 
and system for purifying waste associated with the manufacture of fiber 
glass insulation which is efficient, economical, environmentally 
acceptable, and avoids fire hazards and other disadvantages of currently 
known systems. 
A further object is to provide a process and system as above described in 
which freshly screened water is always pumped through orifices or 
restricted liquid flow paths whereby coagulation is minimized and blockage 
of spray tips, inlet ducts, fans, and, (if used), an electrostatic 
precipitator is prevented. 
Another object of the invention is to purify such waste emissions by 
utilizing scrubbing systems designed to effectively remove particulate 
matter therefrom. 
A specific object of the invention is to purify such emissions by utilizing 
separate scrubbing systems on forming air exhaust from the fiber glass 
insulation forming process and on oven air exhausted from the fiber glass 
insulation oven process. 
Yet another object of the invention is to further purify such emissions by 
channelling scrubbed forming air and oven air through precipitator means 
and discharge prior to ultimate discharge into the atmosphere. 
Yet a further object of the invention is to purify said emissions by 
channelling oven air emissions from the oven process through a scrubbing 
system and then into the forming process where the exhausted forming air 
may be further scrubbed and passed through discharge means prior to 
ultimate discharge into the atmosphere. 
Other objects and advantages of the invention will become apparent from a 
reading of the following exemplary description thereof.

Referring to FIG. 1, which shows a preferred embodiment of the invention, a 
rotary process fiber glass insulation manufacturing system is shown for 
purposes of illustrating and describing a specific application of the 
invention. It will be appreciated, however, that the invention is useful 
in connection with any manufacturing system requiring the regulation and 
purification of gaseous, liquid, and solid waste emissions resulting 
therefrom. 
A fiber glass insulation manufacturing system is shown generally at 50. Raw 
material ingredients typically comprising silica, nepheline syenite, 
borax, soda ash, dolomite, and limestone are batched into an electric 
furnace 51 wherein a glass melt is produced. The molten glass flows from 
the furnace to fiberizer and mat-forming process 55, hereinafter referred 
to as forming process, wherein glass filaments are formed and cut into 
random lengths. Resin 52 is introduced into the forming process in the 
presence of air 53 and water to provide for matting of the glass 
filaments. The resin is sprayed on the mass as it falls downwardly in the 
presence of the co-current air stream to a forming conveyor. The mass, or 
product, is then discharged and conveyed to a continuous curing oven 56 
wherein heated air is circulated in the presence of raw materials 
comprising urea, oil, silane, ammonia, ammonium sulfate and water to set 
the resin and bind the mat together. The product discharged from the oven 
process 56 is then trimmed, the trimmings being pulverized and recycled to 
process (not shown), cut into lengths, and boxed as end product 57. 
Pollutant water, air, and particulate matter is discharged from the forming 
process as shown at 58. Water and entrained particulate matter are drained 
to washwater recycle system 59. The particulate matter is eventually 
discharged through fiber and sludge removel system 31 and compactor 32. 
Washwater drained from the fiber and sludge removal system is cleaned and 
recycled to the manufacturing process. 
It should be particularly noted that useable resin is recovered or 
recaptured and returned to the system. That is, that portion of the resin 
which remains soluble is useable and is recovered; that portion which is 
insoluble is filtered out. 
It will be appreciated that the air discharged from the forming process 
(hereinafter sometimes referred to as "forming air") has entrained 
particulate matter, both of which are pulled from the forming process and 
passed through the forming scrubbing system of the invention, shown 
generally at 60. In the forming scrubbing system, the forming air is 
purified of entrained particulate matter by means of a scrubbing agent. 
The forming scrubbing system cools and humidifies the forming air and 
converts condensible, volatile gases to solid and/or liquid particulate 
matter. the scrubbing agent used in the forming scrubbing system, 
preferably water, is drained therefrom into washwater recycle system 59. 
Similarly, oven air discharged from the oven process containing entrained 
particulate matter and volatile condensible gases, typically in lesser 
volume than the forming air, is passed through the oven scrubbing system 
of the invention, shown generally at 70. It wil be noted that the oven 
scrubbing system is located as closely as possible to the oven to lessen 
the length of duct communicating therebetween and minimize the danger of 
fire caused by the accumulation of particulate matter in the duct. In the 
oven scrubbing system, the oven air is similarly purified of entrained 
particulate matter by means of a scrubbing agent, preferably water. The 
oven scrubbing system converts condensible volatile gases to solid and/or 
liquid particulate matter. In this system scrubbers convert the 
condensible vapors to particulate matter which the precipitator can very 
effectively remove from the gas. The scrubbers also serve to keep the fans 
and ducts clean. The oven scrubbing system cools and humidifies the air. 
The scrubbed forming air and oven air together with entrained particulate 
matter are then channeled via ducts to precipitator 80. The scrubbed 
forming and oven air may be sprayed prior to introduction into the 
precipitator to prevent the collection of dried particulate matter within 
the precipitator. It is advantageous to humidify the air entering the 
precipitator to a very high relative humidity because high relative 
humidity reduces evaporation of water from particulate matter which 
collects on the internals of the precipitator, keeping it in a soft 
condition so that it is easily flushed off. The ducts through which the 
scrubbed forming and oven air pass may be sloped to allow drainage of the 
spray into the precipitator. An automatic plate damper (not shown) 
regulated by conventional temperature sensing means may be installed near 
the precipitator air entry zone so that, in the event a fire develops 
within the precipitator, the damper may automatically shut off discharged 
scrubbed forming air and oven air to the precipitator. Similarly, 
automatic fire spray means (not shown), located proximate to the 
precipitator and engageable by conventional temperature sensing means, may 
be utilized to put out a fire in the precipitator. 
Precipitator 80 may be the conventional wet electrostatic type typically 
including discharge electrodes (perferably having a voltage range between 
40,000 to 60,000 v.), metal collector plates, and washwater spray means. 
In the precipitator, the scrubbed forming and oven air pass through an 
electric field created by the discharge electrodes, and the entrained 
particulate matter thereby acquires an electric charge. The air then 
passes across the metal collecting plates, which have a charge opposite 
that of the charge of the particulate matter, and the particulate matter 
thereby is attracted to and collects on the metal collector plates. 
Washwater spray means washes the particulate matter from the collector 
plates to increase their attraction efficiency and prevent 
over-accumulation of particulate matter thereon which causes fire hazards. 
Particulate matter discharged from the precipitator is channeled into 
washwater recycle system 59 and is eventually discharged via fiber and 
sludge removal system 31 and compactor 32. Thus, it can be seen that the 
air discharged from the precipitator is substantially free of entrained, 
pollutant particulate matter. 
It will be appreciated that the effective operation of the precipitator 
requires the maintenance of a low level of solids in the washwater spray 
means, and the prevention of the accumulation of particulate matter near 
the tips of the washwater spray means to eliminate clogging. Saturation of 
the scrubbed forming and oven air in the ducts leading to the precipitator 
is also an important factor in the overall effectiveness of the 
precipitator by preventing the accumulation of dried particulate matter on 
the collector plates. 
The cleaned air discharged from the precipitator is then passed through 
discharge 90, which may typically include conventional stack means, from 
which it is eventually emitted into the ambient environment. The stack 
should also provide for a sufficiently low exit velocity of the emitted 
air, preferably between 25 to 35 ft/sec., to prevent water droplets from 
being blown out of the stack. 
With respect to the water system, it can be seen that water source 1 is 
provided to introduce the scrubbing agent, in this case water, into the 
purification system in the manner shown. It will be understood, however, 
that the description showing the introduction of the scrubbing agent into 
the purification and manufacturing system is for exemplary purposes, and 
that other suitable fresh water introduction means along the washwater 
recycle system are within the concept of the invention. 
As shown in FIGS. 1 and 3, fresh water is introduced into oven scrubbing 
system 70; the oven system 70 discharges into the precipitator washwater 
system 85 and the precipitator washwater system 85 discharges into the 
forming scrubbing system 60 and fresh water is introduced into the 
precipitator washwater system 85, the precipitator washwater system 85 
discharges into the oven scrubbing system 70 and the oven scrubbing system 
70 discharges into the forming scrubbing system 60. Since the oven air 
present in the oven scrubbing system is hot and typically volatile, it is 
preferable to introduce fresh water into the oven scrubbing system as 
opposed to recycled washwater. Washwater discharged from the oven 
scrubbing system is passed into precipitator washwater system 85 for 
recycling into the precipitator and the forming scrubbing system. 
An alternative system is illustrated in FIG. 2. Specifically, in order to 
minimize the accumulation of water which needs to be used up in the 
process and to facilitate removal of greater volume of water from the 
precipitator washwater system 85 to reduce solids in the precipitator 
washwater system 85, the fresh water is added to the precipitator 
washwater system 85 and discharged to the oven scrubbing system 70. 
Whichever system is used depends on the particular needs that apply for 
water handling in the particular manufacturing process. Washwater 
discharged from the forming scrubbing system 60 is fed into washwater 
recycle system 59 and recycled through the manufacturing system in the 
embodiments of both FIG. 2 and FIG. 3. 
Specific preferred embodiments of critical portions of the purification 
system shown in FIG. 1 will next be described. 
Referring to FIG. 2, it can be seen that in a preferred embodiment of the 
forming scrubbing system, shown generally at 60', includes a plurality of 
scrubbers 61 and 62 in parallel arrangement with respect to each other. 
The scrubbing agent, namely water, is introduced into the forming 
scrubbing system by means of oven scrubbing system 70 via washwater 
recycle system 59 as hereinafter described. Forming air, emitted from the 
forming process and containing entrained particulate matter, is passed 
through the scrubbers for the purpose of substantially removing entrained 
particulate matter, condensing volatiles to particulate matter, cooling 
the air and humidifying the air. 
Scrubbers 61 and 62 may be of the conventional orifice type which permit 
the forming air to flow countercurrently to the flow of the scrubbing 
agent, water, sprayed from a plurality of sprayers within each scrubber. 
Particulate matter in the forming air is thus carried by the spray to the 
base region of the scrubber where it collects in a tank. The parallel 
arrangement of the scrubbers, a preferred embodiment of which comprises 
four scrubbers as shown, accommodates the plurality of air streams present 
in the system. The plurality of streams results from the fact that there 
is a variation in pack density in the forming portion of the manufacturing 
process which results in a plurality of suction vacuums which in turn 
produces air streams having dissimilar pressure and flow characteristics. 
It can be appreciated, therefore, that the amount of particulate matter 
passing through a given scrubber is substantially less than the total 
amount of particulate matter introduced into the forming scrubbing system. 
It is believed that the plurality of scrubbers may produce an increase in 
the overall system efficiency and scrubber effectivenss, with the result 
that the efficiency of the forming scrubbing system as a whole is 
substantially enhanced. 
In a fiber glass insulation manufacturing system wherein the rate of 
introduction of molten glass and resin into the forming process 
approximates 7,250 lbs./hr. and 1,630 lbs./hr., respectively, preferable 
design volumes for scrubbers 61 may range between 20,000 to 24,000 (ACFM) 
and for scrubber 62 between 40,000 and 48,000 (ACFM). 
As noted above, air and entrained particulate matter discharged from the 
forming scrubbing system passes through ducts where it may be sprayed by 
sprayer means 63 to facilitate the eventual discharge and removal of 
particulate matter from participator 80 and eliminate drying and clogging 
conditions from arising on precipitator internals. Washwater discharged 
from the forming scrubbing system is lead into scrubber washwater recycle 
system 59 from which it is ultimately recycled into the manufacturing 
system. 
In like manner, oven air emitted from the oven process containing entrained 
particulate matter is passed through an oven scrubber system 70', here 
shown as including a plurality of impingement scrubbers 64 in the dual 
parallel arrangement. In this embodiment two scrubbers are used so that 
the air collected from each end of the oven can be scrubbed without using 
a long run of duct discharging into the scrubber. 
The oven air typically contains volatile material which will condense when 
the air cools. The oven air is therefore scrubbed with water from the 
precipitator washwater recycle system 85 to remove the condensible 
materials from the oven air and transfer them to the washwater recycle 
system for eventual discharge via fiber and sludge removal system 31 and 
compactor 32. Impingement scrubbers 64 may be of the conventional 
Rotoclone type designed with water and air flow controlling baffles and 
vanes which cause water contained in the Rotoclone to scrub the air which 
is sucked through the water by the fan which is part of the Rotoclone 
equipment. Impeller means are provided against which the oven air is 
directed to separate entrained particulate matter and washwater from the 
air and discharge it into a collection chamber. For the same reasons noted 
above concerning the effectiveness of the parallel arrangement of forming 
scrubbers 61 and 62, the parallel arrangement of impingement scrubbers 64 
maximize removal of particulate matter from the oven air being passed 
through the oven scrubbing system. 
The air and entrained particulate matter discharged from the oven scrubbing 
system may likewise be sprayed by sprayer means 65 to facilitate the 
discharge and removal of particulate matter from precipitator 80 and 
eliminate drying and clogging conditions from arising on precipitator 
internals. It can be seen, therefore, that the accumulation of dried 
particulate matter throughout the purification system, and especially on 
precipitator internals, is substantially eliminated. 
In a fiber glass insulation manufacturing system where in the rate of 
introduction of molten glass and resin into the forming process are 
equivalent to those noted above, a preferable design volume for 
impingement scrubbers 64 may range between 18,000 to 22,000 (ACFM). The 
design volume can be increased depending on demands of oven design and 
fumes desired to be removed from the manufacturing process. 
The following table illustrates a detailed breakdown of design data 
pertaining to the components of the purification system illustrated in 
FIG. 2 and described above: 
______________________________________ 
FORMING SCRUBBERS 61 
Preferred Design Volume 
20,000 to 24,000 (ACFM) 
Inlet Air Temp. Range 
100-130 (.degree.F.) 
Grain Loading 0.272 GR/DSCF (per CFM) 
Pressure Drop Across 
Collector 3-12 (in. water) 
Scrubbing Liquid Type - Preferably water 
Inlet Pressure - Gravity Flow 
Pumping Rate - 20-49 (gpm) 
Recycle Rate - 200-300 (gpm) 
FORMING SCRUBBER(S) 62 
Preferred Design Volume 
40,000-48,000 (ACFM) 
Inlet Air Temp. Range 
100-130 (.degree.F.) 
Grain Loading 0.272 GR/DSCF 
Pressure Drop Across 
Collector 3-12 (in. water) 
Scrubbing Liquid Type - Preferably water 
Inlet Pressure - Gravity Flow 
Pumping Rate - 20-40 (gpm) 
Recycle Rate - 400-600 (gpm) 
OVEN SCRUBBERS 64 
Preferred Design Volume 
18,000-22,000 (ACFM) 
Inlet Air Temp. 200 (.degree.F.) 
Grain Loading 0.091 GR/DSCF (per CFM) 
Pressure Drop Across 
Collector 10 (in. water) 
Scrubbing Liquid Type - Preferably water 
Pumping rate - 10 (gpm) 
ELECTROSTATIC 
PRECIPITATOR 80 
Preferred Design Volume 
150,000 (ACFM) 
Air Temp. Range INLET - 130 (.degree.F.) 
OUTLET - 100-130 (.degree.F.) 
Grain Loading 0.124 GR/DSCF (per CFM) 
Pressure Drop Across 
Collector 0.5 (in. water) 
Inlet Air pressure 
&lt;5 (in. W.C.) 
Velocity Across 
Collector Plates 3.6 (ft./sec.) 
Distance Between 
Collector Plates 12 (in.) 
Effective Collecting 
Plate Length Along 
Flow Path 16 (ft.) 
Total Plate Surface 
Area 25,200 (Sq. Ft.) 
Total Number Plates 
29 
______________________________________ 
An alternate, specific preferred embodiment of the purification system of 
the invention is shown in FIG. 3. The forming scrubbing system and oven 
scrubbing system are shown generally at 60" and 70", respectively. 
It will be appreciated that the flow patterns of air, particulate matter, 
and water in the preferred embodiment of FIG. 3 are substantially 
identical to those shown and described in the embodiment of FIG. 2. It is 
understood, as described in previous discussions, that the fresh water can 
be introduced into the precipitator washwater system or into the oven 
scrubbing system with appropriate changes of water routing as are required 
to preserve a dynamically interconnected system. The embodiment of FIG. 3, 
is intended for use in, for example, a fiber glass insulation 
manufacturing system wherein the rate of introduction of molten glass and 
resin into the forming process approximates 7,200 lbs./hr. and 1,020 
lbs./hr., respectively, however it will be understood that these figures 
are given by way of example, and the rates of introduction may vary widely 
from those stated, depending on many process factors, including factors 
which have no significant relevance to the disclosed inventive concept. 
Conventional forming scrubbers 66 and 67 may be of the venturi type, 
wherein water and air are forced through a small nozzle, or construction, 
which results in good mixing and air-water contact. A preferred embodiment 
of the forming scrubbing system comprises three forming scrubbers 66 in 
parallel arrangement with the two scrubbers 67. Preferable design volumes 
of these scrubbers may range between 40,000 to 48,000 (ACFM) for scrubbers 
66 and between 20,000 to 24,000 (ACFM) for scrubbers 67. It should be 
understood that scrubbers of substantially equal capacity may be used if 
desired; here, the provision of two smaller scrubbers provides closer 
process control to the system operator. 
Oven impingement scrubbers 68 may likewise be of the rotoclone venturi 
type, having a design volume ranging between 18,000 to 22,000 (ACFM). 
The following table illustrates a detailed breakdown of operating data 
pertaining to the components of the purification system illustrated in 
FIG. 3 and described above: 
______________________________________ 
FORMING SCRUBBERS 66 
Preferred Design Volume 
40,000-48,000 (ACFM) 
Inlet Air Temp. Range 
100-130 (.degree.F.) 
Grain Loading 0.101 GR/DSCF (per CFM) 
Pressure Drop Across 
Inlet Size 46 (in.) 
Outlet Size 24 (in.) 
Scrubbing Liquid Type - Preferably water 
Inlet Pressure - 5-7 (psig) 
Pumping Rate - 10 (gpm) 
Recycle Rate - 400-440 (gpm) 
FORMING SCRUBBERS 67 
Preferred Design Volume 
20,000-24,000 (ACFM) 
Inlet Air Temp. Range 
100-130 (.degree.F.) 
Grain Loading 0.101 GR/DSCF (per CFM) 
Pressure Drop Across 
Collector 10 (in. water) 
Inlet Size 30 (in.) 
Throat Size 23 (in.) 
Scrubbing Liquid Type - Preferably water 
Inlet Pressure - 5-7 (psig) 
Pumping Rate - 10 (gpm) 
Recycle Rate - 200-220 (gpm) 
OVEN SCRUBBERS 68 
Preferred Design Volume 
18,000-22,000 (ACFM) 
Inlet Air Temp. 200 (.degree.F.) 
Grain Loading 0.056 GR/DSCF (per CFM) 
Pressure Drop Across 
Collector 10 (in. water) 
Scrubbing Liquid Type - Preferably water 
Puming Rate - 10 (gpm) 
ELECTROSTATIC 
PRECIPITATOR 80 
Preferred Design Volume 
216,000 (ACFM) 
Air Temp. Range Inlet - 130 (.degree.F.) 
Outlet - 100-120 (.degree.F.) 
Grain Loading 0.052 GR/DSCF (per CFM) 
Pressure Drop Across 
Collector 0.5 (in water) 
Inlet Air Pressure 
&lt;5 (in. W.C.) 
Velocity Across 
Collector Plates 4.0 (ft. sec.) 
Distance Between 
Collector Plates 12 (in.) 
Effective Collecting 
Plate Flow Path 19 (ft.) 
Total Plate Surface 
Area 32,300 (sq. ft.) 
Total Number of 
Plates 35 
______________________________________ 
A modification of the rotary process fiber glass insulation manufacturing 
system of FIG. 1 is shown in FIG. 4. Specifically, it will be noted that 
the system illustrated in FIG. 4 is substantially the same as that shown 
in FIG. 1 and described above, except that the system of FIG. 4 does not 
include an electrostatic precipitator which is a costly and relatively 
complicated (and somewhat dangerous) piece of equipment. It will also be 
appreciated that except for the modifications hereinbelow described, the 
characteristics of the system illustrated in FIG. 1 are applicable to the 
embodiment of FIG. 4. 
With respect to the purification system of FIG. 4, it will be understood 
that air and entrained particulate matter discharged from the forming 
process is passed through scrubbers 20, which are disposed in parallel 
arrangement with respect to each other, to maximize removal of particulate 
matter in the scrubbing process as previously noted. Water is provided to 
scrubbers 20 by means of the washwater recycle system. Washwater and 
entrained particulate matter discharged from scrubbers 20 are carried to 
washwater recycle system 59, wherein the water is ultimately recycled to 
the manufacturing process and the particulate matter is eventually 
discharged via fiber and sludge removal system 31 and compactor 32. Air 
discharged from scrubbers 20 is passed through discharge means 90, 
typically comprising conventional stack means as previously noted, and is 
ultimately emitted into the atmosphere at environmentally suitable levels. 
Scrubbers 20 may be of the conventional venturi type, providing for 
increased velocity of the forming air flowing concurrently with the flow 
of the scrubbing agent; i.e.: water, in the respective scrubbers. 
Particulate matter is thereby removed from the forming air and is carried 
by the scrubbing agent to the base region of the scrubbers where it 
collects in a tank. In a preferred embodiment, the forming scrubbing 
system comprises two scrubbers 20, although only one scrubber may be used, 
or additional scrubbers may be added, within the concept of the invention. 
It will also be noted that oven air and entrained particulate matter 
discharged from the oven process are channeled through impingement 
scrubber 21, located in close proximity to oven 56 to minimize the length 
of duct communicating therebetween and thereby minimize fire risks. 
Scrubber 21 may be of the conventional rotoclone type. Impeller means are 
provided against which the oven air is directed to separate entrained 
particulate matter from the air and discharge it into a collection 
chamber. The scrubbing agent, fresh water, is introduced into scrubber 21 
from water source 1. In a preferred embodiment, only one scrubber 21 may 
be used, however, the addition of other scrubbers is within the concept of 
the invention. 
Air and entrained particulate matter discharged from scrubber 21 is 
channeled into the forming process, from which the particulate matter is 
ultimately discharged and further purified with the forming air by means 
of venturi scrubbers 20 and discharge means 90. It will be appreciated 
that cycling of the scrubbed oven air into the forming process reduces the 
total volume of air handled in the purification system which maximizes 
efficiency. It will also be noted that the forming process itself acts as 
a purification means for the scrubbed oven air introduced therein since at 
least some particulate matter entrained in the scrubbed oven air will be 
integrated into the green product. 
In a fiber glass insulation manufacturing system wherein the rate of 
introduction of molten glass and resin into the forming process 
approximates 2,000 lbs./hr. and 300 lbs./hr., respectively, preferable 
design volumes for scrubbers 20 may range between 23,000 to 27,000 (ACFM) 
and for scrubber 21 between 13,000 to 17,000 (ACFM). 
The following chart illustrates a detailed breakdown of operating data 
pertaining to the components of the purification system illustrated in 
FIG. 4 and described above: 
______________________________________ 
FORMING SCRUBBERS 20 
Preferred Design Volume 
23,000-27,000 (ACFM) 
Inlet Air Temp. Range 
100-130 (.degree.F.) 
Grain Loading 0.172 GR/DSCF 
Pressure Drop Across 
Collector 22 (in. water) 
Inlet Size 30 (in.) 
Throat Size 23 (in.) 
Scrubbing Liquid Type - Preferably water 
Inlet Pressure - 5-7 (psig) 
Pumping Rate - 2 (gpm) 
Recycle Rate - 10 gal. per 
1,000 ACFM 
OVEN SCRUBBER(S) 21 
Preferred Design Volume 
13,000-17,000 (ACFM) 
Inlet Air Temp. 200 (.degree.F.) 
Grain Loading 0.043 GR/DSCFM 
Pressure Drop Across 
Collector 10 (in. water) 
Scrubbing Liquid Type - Preferably water 
Pumping Rate - 0.2 (gpm) 
______________________________________ 
Although preferred embodiments of the invention have been illustrated and 
described, it will be apparent to those skilled in the art that variations 
and modifications may be made within the scope of the inventive concept. 
Accordingly, it is intended that the scope of the hereinafter appended 
claims when interprested in light of the prior art, and not by the scope 
of the specific, exemplary preceding descriptions.