clean air product selector - sly inc
TRANSCRIPT
The above illustrationdepicts typical plant emission sources. Forequipment selection, identify the process whichis most similar to yours.Once the process is identified, match the colors to the icons at rightfor preliminary equipmentselection. Depending onconditions and collection
requirements, most applications have multiplepotential solutions.Therefore, a variety ofpotential products areshown. Your Sly represen-tative can offer expertselection assistance todetermine the best airpollution control productsto meet your specificneeds.
Potential Applicationsof Sly Products
111
13
10
9
8
12 7 6
45
4
3
Impinjet® Wet Scrubber
Venturi Wet Scrubber
Eductor Venturi Scrubber
Venturi/Impinjet® Wet Scrubber Combination
TubeJet®/Impinjet® Wet Scrubber Combination
Pactecon® Collector
Reverse Air Collector
Shaker Collector
TubeJet® Collector
PleatJet™ Collector
Plant Processes
Dry bulk storage
Liquid bulk storage
Weigh bins
Mixer/reactor
Vibratory feeder
Reactor/slurry tanks
Dryers
Screener
Packaging operations
Size reduction equipment
Filter receiver
Filling operations
Centralized dust/fume/odor/vapor collection system
Cogeneration plant
Incineration plant
Coal or oil-burning power generation plant
Solid or liquid waste handling
Loading spouts
Product Icons
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
1
Combo
ComboCombo
Combo
Combo
1
1415
2
18
16
17
Impingement Scrubber
Venturi Scrubber
Packed Tower
Dry Cyclone Collector
Typical Particles
Particle Size, Microns.001 .01 0.1 1.0 10 100 1000
U.S. Screen Mesh
CARBON BLACK
GAS MOLECULES
PAINT PIGMENTSOIL FUMES
METALLURGICAL FUMES
ZINC OXIDE FUMES
MAGNESIUM OXIDE FUMES
RESIN SMOKE
STOKER FLYASH
GROUND LIMESTONE
PULVERIZED FLYASHHUMAN HAIR
GROUND TALC
S03 MIST
MILLED FLOUR
CEMENT DUST
ALKALI FUMES
PHOSPHATE ROCK DUST
METALLURGICAL DUST
A.C. FINE TEST DUST
H2S04 MIST
NH4 CL FUMES
32520
3040
5060
80100
120140
170270 200
230
Fabric Collector
PM-10
Information to Assist You in Understanding Your Problem
2
This chart provides relativesizes of commonly encounteredairborne materials. This information is to be used inconjunction with the selectionand sizing guidelines presentedin this brochure.
For assistance in under-standing how Sly can solveyour problem, call your localrepresentative or Sly at1-800-334-2957.
Blue areas indicate the most appropriate range for the various collection technologies shown in leftcolumn.
Cartridge Envelope Tube ImpingementFilter Filter Filter Baffle Plate Venturi Eductor
Particle Size: > 10 µ
Inlet loading:
Light - <1 gr/cf
Medium - 1-4 gr/cf
Heavy - 5-10 gr/cf
Very Heavy - >10 gr/cf
Particle Size: < 10 µ-PM 10
Inlet loading:
Light - <1 gr/cf
Medium - 1-4 gr/cf
Heavy - 5-10 gr/cf
Very Heavy - >10 gr/cf
Particle Size: < 1 µ-Sub Micron
Inlet loading:
Light - <1 gr/cf
Medium - 1-4 gr/cf
Heavy - 5-10 gr/cf
Very Heavy - >10 gr/cf
Temperature: <275°F
<375°F
>375°F
Dewpoint: Ambient
Process Moisture Added
Saturated
Hygroscopic
Granular
Fluffy/Fibrous
Sticky
Abrasive
Corrosive
Vapor
Mists
Condensing/Cooling
3
Appropriate for most applications Appropriate for some applications Generally not appropriate
Dry Filter Selection Wet Scrubber Selection
Sly Inc. sells three basic styles of wetscrubbers: the Impinjet® impingementbaffle plate; Venturi and Eductor.
Sly Inc. sells three basic styles of drycollectors: cartridge, envelope andtubular bag filters.
0.5 0.6 0.7 0.8 0.9 1.0 1.1
GRAPH C PARTICLE SIZE/TEMPERATURE FACTOR
TEM
PERA
TURE
(°F)
LESS THAN 3 MICRONS
1.2
275
250
225
200
175
150
125
100
75
3 TO 10 MICRONS
10 TO 50 MICRONS
50 TO 100 MICRONS
OVER 100 MICRONS
C
0.7 0.8 0.9 1.0 1.1 1.2 1.3
10
9
8
7
6
5
4
3
2
1
GRAPH B2 PROCESS FACTOR
GRAI
N LO
ADIN
G (G
RAIN
S/FT
3 )
PROCESS GAS CURVE
PRODUCT COLLECTION CURVE
NUISANCE VENTING CURVE
B2
0.60 0.65 0.70 0.75 0.80 0.85 0.90
100
90
80
70
60
50
40
30
20
10
GRAPH B1 PROCESS FACTOR
GRAI
N LO
ADIN
G (G
RAIN
S/FT
3 )
PROCESS GAS CURVE
PRODUCT COLLECTION CURVE
NUISANCE VENTING CURVE
0.95 1.00
B1
Guidelines for CalculatingAir-to-Cloth RatiosOperating experience is unquestionably the best reference for determining air-to-cloth ratios (A.C.R.). However, the informationbelow may be used as guidelines:
A.C.R. = Materialx Processx Particle Size/Temperature
Step 1To determine the Material Factor, find your material and select the appropriate valuefrom the Material Factor Table. (Table A, top right.)
Step 2Material Loading is expressed in grains per cubic foot.
The Process Factor is a function of the inlet grain loading and type of process. Firstdetermine the material loading which is expressed in grains per cubic foot (gr/cf).
To calculate gr/cf from lbs/min,Multiply: 7,000 gr/lb x lb/min = gr/cf
CFMNext, establish the process curve which most closely defines your application. The following applications are listed as guidelines.
The applications are defined by:- Process Gas Filtration: Dryers, Kilns, Reactors- Product Collection: Air Conveying, Size Reduction, Classifying- Nuisance Venting: Bulk Material Handling
To determine the Process Factor, use either:- Graph B1, if your grain loading is > 10 gr/cf- Graph B2, if your grain loading is < 10 gr cf
On the graph, find your grain loading and move horizontally to the appropriate application curve. Move vertically to the bottom of the graph to obtain Process Factor.
Step 3The air-to-cloth ratio is also affected by temperature and particle size. Graph C is used todetermine your Particle Size/Temperature Factor. Locate the temperature of your application and move horizontally to the appropriate particle size curve. Then move ver-tically to the bottom of the graph to obtain the Particle Size/Temperature Factor.
Step 4Calculate the air-to-cloth ratio: A.C.R. = A x B x C
Example:Ventilating a belt conveyor bucket elevator and screen handling, silica sand at ambienttemperature with an estimated inlet loading of 2 lb/min. Air volume is 5,000 CFM.Average particle size is greater than 10 microns.
A.C.R. = 8 x 1.1 x 1.0= 8.8 : 1
A filter’s design and cleaning mechanisms affect the final filter ratio. This additional equipment factor must be considered and is noted on the specific TechnicalData Sheet of the dust collector being considered. Consult your Sly representative or Slyat 1-800-334-2957.4
TABLE A MATERIAL FACTOR TABLE
MATERIALFACTOR 9 8 7 6 5
MATERIAL
GRAINPAPERSAWDUSTTOBACCO
KAOLINSANDGYPSUMLIMESALTSODA ASHTALCABRASIVES
ALUMINAMETALLIC ORECEMENTCOALFLOURFERTILIZERLIMESTONE
COKEPIGMENTSFLYASHDETERGENTSLEAD OXIDESUGAR
ACTIVATED CARBONCALCIUMCARBON BLACKGRAPHITECHARCOALMETALLURGICAL FUMEZINC OXIDE
A
[
Velocity.75
4005
2( ([ [4000.75
4005
2[ = 1.77"
= InletLoss
34567
89101112
1314151617
1819202122
2324252627
2829303132
3334353637
3839404244
4648
.049
.087
.136
.196
.267
.349
.442
.545
.660
.785
.9221.0691.2271.3961.576
1.7671.9692.1822.4052.640
2.8853.1423.4093.6873.976
4.2764.5874.9095.2415.585
5.9406.3056.6817.0697.467
7.8768.2968.7279.62110.56
11.5412.57
147262409589802
1,0471,3251,6361,9802,356
2,7653,2073,6824,1894,729
5,3015,9076,5457,2167,919
8,6569,425
10,22611,06111,928
12,82813,76114,72615,72416,655
17,81918,91520,04421,20622,400
23,62724,88726,18028,86331,676
34,62337,699
171306478687936
1,2221,5461,9092,3102,749
3,2263,7424,2954,8875,517
6,1856,8927,6368,4199,239
10,09810,99611,93112,90513,916
14,96616,05417,18018,34519,548
20,78722,06823,38524,74026,133
27,56529,03530,54333,67436,955
40,39443,982
196349546786
1,069
1,3961,7672,1822,6403,142
3,6874,2764,9095,5856,305
7,0687,8768,7279,621
10,559
11,54112,56613,63514,74815,904
17,10418,34819,63520,96622,340
23,75825,22026,72728,27429,867
31,50333,18334,90638,48442,234
46,16450,266
220393614884
1,202
1,5701,9882,4542,9703,534
4,1484,8115,5226,2837,093
7,9528,8619,818
10,82411,879
12,98314,13715,34016,59217,892
19,24220,64122,08923,48625,133
26,72828,37330,06631,80933,600
35,44137,33139,27043,29547,513
51,93556,549
245436682982
1,337
1,7462,2092,7273,3003,927
4,6095,3456,1366,9827,882
8,8369,845
10,90812,02713,199
14,42615,70817,04418,43519,880
21,38122,93524,54426,20727,925
29,69831,52533,40735,34337,434
39,37941,47943,63348,10652,793
57,70562,850
PIPEDIAMETER(INCHES)
PIPEAREA
(SQ. FT.)
VELOCITY FPM (FEET PER MINUTE)
3000 FT. 3500 FT. 4000 FT. 4500 FT. 5000 FT.
VELOCITY PRESSURE, INCHES W.G.
.561 IN. .764 IN. .998 IN. 1.262 IN. 1.558 IN.
PIPEDIA.
AVEL.
C
PIPELENGTHIN FT.
B
FRICTIONLOSS IN
INCHES OFWATER D
LINER
508000
40
7000
30
6000
205000
4000
109
8
73000
6
5
4
3 2000
2
.01
1
.05
.1
3
456789 .
2
.3
.4
.5
10
20
30 .6.7
40 .8.9
50 1.0
100 2
200 4
56789
300
400
500 10
To find the friction loss in a pipe of given diameter (A) and length (B) with air moving at a given velocity (C):
1. Connect A and B to a point on line R.
2. Connect point on line R with C.
3. Read loss on line D.
Example: As indicated by dot and dash lines, a 6" pipe (A) 53 feet long (B) with velocity of 4250 FPM (C) will have a loss of 2.4 inches (D).
How To Use Friction Loss Chart:
3
5
Friction Loss Chart
Duct Sizing &Static Pressure Loss
Air Volumes in Pipe Lines at Various Velocities andCorresponding Velocity Heads in Inches of Water
Inlet LossesEstimated inlet losses for standard conditions may becalculated by the following formula:
Typical Inlet Losses(To maintain suction at ventilation point)3000 FPM ......................1.00 in.3500 FPM ......................1.36 in.4000 FPM ......................1.77 in.4500 FPM ......................2.24 in.5000 FPM ......................2.77 in.
Fan Static PressureTotal fan static pressure = Inlet loss + Friction loss in piping+ Loss through filter equipment + Loss through fan exhauststack or weather cap
Equivalent Resistance In Feet of
Straight Pipe
DIA.OF PIPE
90° ELBOW*
3"4"5"6"7"8"
10"12"14"16"18"20"24"30"36"40"48"
3 FT.4 FT.6 FT.7 FT.9 FT.
10 FT.14 FT.17 FT.21 FT.24 FT.28 FT.32 FT.40 FT.51 FT.64 FT.72 FT.89 FT.
* For 60° elbow, multiply by 0.67. For 45° elbow, multiply by 0.50.
2D
D
Sly’s Approach to AirPollution Control:• conservative design• flexible engineering• controlled manufacturing• comprehensive field
services
6
Founded in 1874, Sly has been providingsolutions to environmental problems sincethe turn of the century. From the beginning,we have done all our engineering andmanufacturing in-house.
Many companies makeair pollution controlequipment, but none havebeen doing it as long as Sly.
Nearly a century haspassed since our originalpatent for cloth dust filters.Over the years, we’velearned plenty about theapplication and fabricationof dust collectors andscrubbers. Here are themain points:
“In the pollutioncontrol business,conservativeapplication oftechnology is best.”
Equipment misappli-cation has no place in thepollution control business.Not only is improperequipment apt to fall shortof collection requirements,it is oftentimes moreexpensive to operate thanthe proper machinery. Forexample, incorrect sizingand improper media choicecan easily lead to excessivemaintenance and costlydowntime. When you dealwith Sly, we have your bestlong term interests inmind.
“We believe in fittingthe equipment to thecustomer’s needs, notthe customer to theequipment’scapabilities.”
Unlike many equip-ment suppliers, we refuse
to mass-produce product andthen hope for a good fit. Wehave maintained flexibility inour engineering techniqueswhich permit us tomanufacture each order tofit the task at hand, whilemaintaining a price to youthat is comparable to mass-produced equipment.
In many cases it costs nomore to get the very bestequipment for the job.
This approach earns usthe respect and repeatbusiness of many sophisti-cated buyers of pollutioncontrol equipment. Thesepeople, many of whom buydozens of collectors orscrubbers every few years,have always represented alarge portion of ourcustomer base.
“We build our ownequipment...for somevery good reasons.”
Part of the reason Slycan custom-make a collectorfor you while keeping acompetitive price is just that:we are the manufacturer.Unlike the majority of ourcompetitors, we don’t jobout our production. We doour own engineering,sewing, metal fabrication,painting, assembly, qualitycontrol, and laboratory R&D.This way we control everystep of the process, allowingus great flexibility to buildthe best collector or
scrubber for your individualneeds. We have a strongcommitment to shippingdates and routinelyguarantee ship dates whenrequested.
“Our obligation to thecustomer doesn’t endwhen the equipment isshipped.”
Sly’s staff engineers canpromptly assist you introubleshooting or withother field service problemsshould they arise at yourfacility. This commitmentto total customer supporthelps guarantee superiorvalue for your investment.
“We’re a privatecompany, and intendto stay that way.”
The corporaterestructurings and shortterm goals of today’sbusiness scene aren’t for us.Sly is owned and operatedby descendants of thefounding family. We are inthe business for the longrun, and will maintain theprofessionalism andcontinuity required tocontribute to the longterm success of yourbusiness.
7
All assembly and testing is performed in our ownplant. We control the quality and delivery scheduleto an extent not possible from other suppliers, mostof whom sub-contract much of their work.
Dust, fumes or vapors can occur singularly or in many combinations. Only a company with Sly’s level of experienceis capable of tailoring the correct air pollution controlequipment to your specific application.
All our collectors are made under ourroof...from cutting fabric for filterbags to painting.
Sly employs the most modern automated engineering techniques,allowing us to respond quickly with custom-tailored designs to fityour needs. Options and specials are no problem for us.
Sly TubeJet® dustcollectors offer on-linecleaning with a steadypressure drop. Bag changesare exceptionally easy withour “no tools required”design. Capacities to200,000+ CFM.
Ask for our TubeJet Catalog.
8
Pulse Jet Collectors
Snap ring filter bags, cages and pulse pipes areremoved and installed quickly without tools.
The Sly TubeJet collector offers low cost installation and easy maintenance. It arrives factory-wired, factory-painted (primed insideand out, with an enamel finish on external surfaces), and ready for installation.
9
Conservative application of equipment and filter media results inhigh collection efficiencies. Continuous on-line cleaning isaccomplished with low consumption of compressed air.
Rugged construction is standard for Sly TubeJet collectorswhich feature 12 gauge design for operation to +20" W.G.
Cylindrical TubeJet collectors are for high pressure/highvacuum applications. All-welded construction permits rangesof +20" W.G., +100" W.G., and +17" Hg. Top or side bagremoval styles available.
Pulse-CleanedEnvelope Bag Collectors
Sly Pactecon® collectorsoffer advantages only available with envelopebags: low headroom, outside bag removal andcompact overall size.Additional advantages arecontinuous operation withoff-line cleaning, anddownflow design whichleads to long bag life. Easyinstallation; bags shippedinstalled. Capacities to100,000+ CFM.
Ask for our PacteconCatalog.
Collectors are cleaned off-line, cell-by-cell...contributing to long bag lifeand low compressed air consumption.Filter bags and bag cleaning systemare completely factory-installed.
10
Standard modules can be easily configuredto handle large air volumes.
11
Rectangular envelope bagsprovide several unique advantages: maximum filterarea in a minimum filter housing size, low headroomdesign, and safe side bagremoval from outside the collector.
Unlike most pulse-cleaned collectors, we use a downflowdesign which enhances particulate separation. Bag life isextended by minimizing cleaning cycles.
Shaker-Cleaned Envelope Bag Collectors
If your applicationpermits intermittentoperation, consider a SlyShaker collector, which issimple to operate andmaintain. Filtering velocitiesare low, which providesuniform dust distributionand long bag life.Accumulated dust isintermittently shaken offfilters while air flow istemporarily interrupted.
Ask for our Shaker Catalog.
12
Long, trouble-free service for non-continuous applications. Ideal for binvents where no compressed air isavailable.
Vertical Cartridge Collectors
The Sly PleatJet™
Cartridge collector offersthe fastest filter changesanywhere!
Maximum capacitiesare realized by dual stageseparation systemconsisting of a classifierinlet and internal bafflingsystem. Capacities to50,000+ CFM.
13
Ask for our PleatJet Catalog.
The Sly PleatJet collector offers low initial cost,low headroom requirements, and virtuallyeliminates dust reentrainment. Pleat-lock designmaintains maximum filter surface area.
Avoid dust during cartridgechanges– Sly’s linkedcartridges are easilyremoved at waist level
14
PleatJet II™ Horizontal Dust Collectors
Specially engineered Opti-Pulse™ venturi pulsesystem maximizes energy release … provides moreuniform dust release. Cleans all of the cartridge,including the hard-to-clean cartridge tops which arenot cleaned by conventional pulse systems.
Plus, the PleatJet II is loaded with standard featuresthat you probably would pay extra for with othercollectors.
Optimized Opti-Pulse™ Cartridge Cleaning System Delivers OptimalCollector Performance.
• Optimal cartridge cleaning √ Opti-Pulse venturi cleaning system√ MP-404™ timer with “Clean-On-Demand” module
• Long service life √ All welded (one piece) construction√ Heavy duty cartridge support (not cantilevered)
• An exact fit to your needs √ Modular design offers a multitude of configurations√ Multiple inlet and outlet locations√ Accommodates low head room
• Easy maintenance √ No-tools quick release doors√ Uses industry standard cartridges√ Cleaning system accessible from grade
You get this… …because we do this!
0
100
90
85
95
PARTICLE SIZE, (MICRONS)
EXPE
CTED
EFF
ICIE
NCY
%
PARTICULATE COLLECTION EFFICIENCIES
1.0 2.0 3.0 4.0 5.0
1–STAGE IMPINJET®2–STAGE IMPINJET®
20' ∆P VENTURI
30' ∆P VENTURI
.40
VOLUME CORRECTION FACTOR
INLE
T M
OIST
URE,
#H 2
0/#D
RY A
IR
VOLUME CORRECTION CHART
.35
.30
.25
.20
.15
.10
.05
.40 .45 .50 .55 .60 .65 .70 .75 .80 .85 .90 .95 1.00
2000
°
1500
°
1250
°
1000
°
750°
500°
450°
350°
250°
225°
200°
175°
150°
125°
Basic Criteria forSizing A Wet Scrubber
15
The first step is todetermine which type ofSly scrubber to select. Thenature of the pollutant orcontaminant will deter-mine if the Venturi,Impinjet, Packed Tower orcombination scrubbersystem is best suited foryour application. (Seepages 2 & 3.)
Sizing the scrubber isthe next step. The factorsaffecting sizing are gasflow rate, temperature,pressure, gas composition,humidity, contaminantloading and desired outletrequirements. Also, theavailability of an appropri-ate scrubbing liquid is animportant consideration.
Gas streams entering awet scrubber may or maynot be fully saturated,however they will exit thescrubber fully saturated.This process of saturationresults in a change involume, temperature anddensity.
The overall scrubbersize (diameter) is afunction of velocity ofsaturated gas through thescrubber shell. Knowingthe moisture content of agas stream (generallyexpressed as pounds ofwater per pound of drygas) and the inlet tempera-ture, the saturationtemperature and saturatedvolume content can becalculated. The volumecorrection chart at theright can be used for aclose approximation of thechange in gas volume.
Example:10,000 ACFM @ 450°Fcontaining 0.15# H2O/#dry air
The chart shows acorrection factor of 0.75.Inlet volume x correctionfactor = outlet volume or10,000 x 0.75 = 7500 ACFM.The scrubber would be sizedfor this saturated outletvolume.
For Impinjet scrubbersthe maximum capacity isbased on shell velocity of 500feet per minute. Dividing thecorrected or saturatedvolume by 500 yields theoverall tower cross-sectionalarea from which the diametercan be determined.
Example (continued):7500 ft3/min = 15 ft2
500 ft/min
Area = 15 ft2 = πD2
4D=diameterDiameter = 4.37 ft
The calculated diameterbecomes the reference pointfor equipment selection.(Refer to specific productcatalog.)
The approximateparticulate and/or mistefficiencies for Venturis andImpinjet scrubbers can bedetermined by the efficiencychart on the right.
To determine the numberof Impinjet stages requiredfor the absorption of gasessuch as acids requires acomplex calculation with toomany variables to use a
simple chart. However thefollowing information isimportant:- gas volume- process description- temperature- particle size- moisture content- type of contaminant
For assistance in under-standing your problem, callyour local representative orSly at 1-800-334-2957.
Impinjet® Scrubbers
Sly Impinjetscrubbers clean, cool andabsorb gases and collectparticulates. Highcollection efficiencies(98+% @5 microns) areachieved with low waterconsumption andminimum pressure drop.Capacities to 200,000+CFM.
Ask for our Scrubber Catalog.
16
Constructed in either metal or plastic,each stage acts as a discreetfractional collector. Multiple stagedesigns are available to maximizeefficiencies.
Highly resistant to fouling, the Impinjetcollector is the ideal scrubber forapplications requiring both absorptionand particulate removal. Completepackage systems are available.
Venturi Wet Scrubbers
The Sly Venturi scrubberefficiently collects fineparticulate and mists.Scrubbing liquid is atomizedinto fine droplets whichentrap particles. Adjustablethroats for performanceoptimization are standard.Capacities to 100,000+ CFM.
Designs are available forhigh temperature, highlycorrosive applications.Venturis can be coupledwith Impinjet scrubbers orPacked Towers to achievemaximum efficiencies.
Ask for our Scrubber Catalog.
17
Packaged, shop assembled systemscomplete with instruments and controls areavailable. The standard manually adjustablethroat can be automated for remoteoperation.
Eductor Scrubbers
Venturi and cyclonicseparator
Eductor scrubbers aredesigned to remove solublegases and particulate byinducing a gas flow usinghigh pressure liquid focusedinto a venturi throat.Additionally, eductorscrubbers can be used fordirect-contact condensation.
A high liquid flow ratemakes the Sly eductorparticularly appropriate forcollection of sticky and/orgummy particulate, as wellas gases which decomposeupon contact with water,such as SiCl4 and H2SiF6.
Ask for our Scrubber Catalog.
18
CFanInlet Gas
Automatic AdjustableThroat
Venturi Impinjet
ChemicalAddition
Blowdown
Pump
Tank
Fresh H 02
To Stack
CombinationScrubber Systems
If ultrafine particulateand noxious gases are presentin the same gas stream,special combinations ofscrubbers are appropriate. A typical example is incineration, which calls firstfor a Venturi to remove fineparticulate and then anImpinjet scrubber to absorbthe gases. Complete packagesystems, includinginstrumentation andcontrols, are available.
Printed in U.S.A.
Catalog PS-100201
©2007 Sly Inc.
PleatJet is a trademark and Pactecon,Dynaclone, TubeJet and Impinjet are registered trademarks of Sly Inc.
DOING OUR PARTPrinted on recycled paper.
P. O. Box 5939Cleveland, OH 441011-800-334-2957(440) 891-3200Fax: (440) 891-3210Web: www.slyinc.comE-mail: [email protected]
SLYINC
TECHNOLOGY FOR ACLEAN ENVIRONMENT