J.
ANNUAL REVIEW
L. ENGLESBERG
FILTRATION-THEORY Progress has been made in the deuelopment of
useful theories and design concepts iltration theory is catching up with practice.
Among
F the articles which attempt to deal with filtration
in more basic terms is one in which a mixture of two slurries (76A) was employed to investigate the correlation between the filtration characteristic of slurry mixtures and their ingredients using the Ruth compressionpermeability cell. This method, combined with apparatus for determining hydraulic pressure distribution, affords a basic tool for obtaining data analogous to temperature distribution curves in heat transfer. Many other articles give design methods for various types of filters and of filter system components. Abstracts of a selection of such articles are given below. Automation is now a n important factor in filtration equipment, reducing the costs of labor. Pressurized filtration equipment shows growth, because of higher operating temperatures. Materials are also affected by the increase in desired operating temperature-space manufacturers are looking for filter media capable of withstanding temperatures to 700’ F. Many filter media are available today to suit specific applications. Guidelines (7OB) for selecting the best medium help in narrowing down the field. Recent developments in the field of nonwoven filter media have added greatly to the technology of filtration. A review covering the last three years (26B) shows areas where various nonwoven fabrics have replaced other media. I n certain industries, air pollution problems are being solved by filtration. I n areas where waste dusts from local plants have left a characteristic coating on every nearby exposed surface for years or decades, glass-cloth filters have wrought a conspicuous change, favorably affecting living and working conditions and even property values. These filters (in the form of huge bags) achieve virtually 100% filtration. The same filters have proved equally eficient in applications such as carbon-black manufacture ( 78B),where the end product itself is a dust. Microfiltration is no longer a laboratory tool. Cellulose acetate filters ranging in pore size from 5 microns down to 10 millimicrons are finding increasing uses in research and development projects where contaminants must be controlled, where particles need to be sized,
A N D PRACTICE
counted, weighed, or classified microchemically. Microfiltration (ZOB) has become perhaps the most widely employed method for cleaning reagents, solvents and gases for use in instruments and analytical methods. Many other applications for the filter will occur to those who work in fields of fine chemicals, fluorescence analysis, electromicroscopy techniques, photography, crystal growth, and microchemical methods. The First International Filtration Symposium and Exhibit ( I H ) was held in London, 11-14 February 1964. Forty-six firms from the United States, Britain, France, Germany, and Switzerland showed their latest developments in the filtration field. Papers read included “The Nature and Behaviour of Contaminant Particulate Matter,” “Liquid Filtration in Industry,” “Filtration in Aircraft Hydraulic Systems,” “The Use of Filter Aids in Filtration,” “Polishing Filtration in the Process Industries,” “Digest of Air Filtration,’’ “Application of Pressure Filters for the Dewatering of Sludges,” “A Unique Approach to Fine Filtration,” “Filtration of Cutting Oils and Coolants,” “Air Hygiene-Setting, Meeting and Maintaining a Standard,” and “Highefficiency Air Filtration in the Atomic Energy Industry.” Copies of these papers may be obtained from Town and Country Exhibitions, Ltd., 145 Oxford Street, London, or from Fluid Handling at the same address.
ABSTRACTS OF ARTICLES Theory
The simplicity of the filtration design equations (IOA) are demonstrated by using heat-transfer equations as a n analogy. A filtration theory for compressible fibrous beds formed from dilute suspensions ( 7 7 A ) is presented. The application of the theory to paper making is discussed and need is shown for further research. A theory of diatomite filtration ( 7 A ) is evolved to aid in determining the optimum filter operating characteristics for producing potable water at the lowest cost. An equation is derived. A modified form of diatomite filtration equation (2%) involving the average specific resistance corresponds to established filtration practice, and relates resistance of clean filter aid in the precoat to that of dirty filter aid in the rest of the cake. A new definition of specific filtration resistance (73A) takes into account slurry concentration as well as applied pressure. Equations (77A) are derived for local and average porosity in a filter cake under controlled conditions. A simple constant-pressure filtration method VOL. 5 6
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was developed at the Forest Products Laboratory (5A) for obtaining the average specific filtration resistance of pulps. The system utilizes a constant-pressure tube, an electronic load cell, and a recorder system. The optimum operating rate for a filtration plant ( 4 4 ) is defined as the rate that results in maximum production per filter run and therefore minimum backwash percentage. The over-all optimum body feed, optimum filtration rate and optimum terminal head loss combine to produce minimum cost per gallon of potable water. These optimums (9A) are influenced by four cost factors -labor, power, diatomite, and equipment costs. -4 simple graphical solution ( 8 A ) can be used to design the washing operation for a filter cake on a rotary filter. Two articles by the same author (78A, 79A) give a formula for calculating the diameter of the largest pore of a hydraulic filter by means of bubble point tests, and discusses deviations from theory. A third article (6A) on bubble point filter tests discusses these two papers and describes further deviations from theory. There is an optimum concentration of flocculant which produces the maximum settling and filtration. It is possible to project mathematically (3A) the extent of flocculation needed to increase or decrease filtration. The design of a pressure filter system involves much more than just calculating the necessary filter area. A number of interrelated problems (7A) must be analyzed, including type of filtration, pump characteristics, filter media, and material handling aspects of the filter. Filtration formulas ( l 5 A ) are derived for sizing filters and pumps, and for determining filtration cycles. Standards are needed to clarify micrometer ratings of filters. Road dust called “AC test dust” ( 7 4 4 ) is probably the most practical artificial contaminant. Filter Aids and Filter Media
Miscellaneous Filter Media. Many articles have described properties and applications of various filter media. The asbestos filter pad (23B) is a depth-type filter which not only possesses a gradient densit) structure to trap solids but also has an adsorptive property to attract solids. It can also be used for sterile filtration. Metallized fibers (2 IB) duplicate the mechanical sieving and sorption of ordinary fibers, are not fragile, and are fully applicable to high temperatures. Activated carbon can now be produced in sheet form on paper fiber, glass, ceramics, quartz, and manila hemp (76B). High on the petroleum industry’s list of field problems through the years has been migration of sand into oil wells. Conoco has developed a chemical slurry (79B), which when pumped to the desired downhole point, forms a permeable plug or filter to strain out sand. A stacked column of disks made of metal or plastics ( I S B ) with precision calibrated grooves in the shape of equilateral triangles, graduated in size from the outer to the inner rim, is said to give absolute filtration from 750 to 1 micron. Details of a highly efficient air filter (6B) used to collect radioactive particles in the upper atmosphere have been revealed. The paper consists of a porous sheet of 66
INDUSTRIAL A N D E N G I N E E R I N G CHEMISTRY
minimum-refined pulp impregnated with dibutoxy ethyl phthalate which remains sticky between 40” to 100°F. Wheelabrator Corp. has developed a polyester fiber filter fabric of napped flannel that permits efficient dust collection at ratios of air-to-cloth higher than those associated with cotton sateen fabric (9B). Cellulose Acetate Media. As noted previously, cellulose acetate filter media have made microfiltration processes practical. A cellulose acetate membrane filter (22B) has a sufficiently weak infrared spectrum to permit direct examination of samples by means of the infrared differential technique. Sources of error (25B) in the use of membrane filters for weight determination were investigated. The effect of humidity on the reliability of gravimetric determinations using acetate membrane filters (2B) was investigated. A new and rapid technique for determining the carbon tetrachlorideinsoluble portion of bitumen materials uses a commercially available membrane filter (24B). The authors show good correlation between the new technique and the standard ASTM procedure. Three reports (4B, 5B, 74B) describe the use of membrane filters in the filtration of beer. Conventional pasteurization of beer is giving way to a simple technique based on microfiltration. Membrane filter counts were compared with most probable numbers of coliform in San Diego’s sewage system and found to be equal or higher than conventional MPN results (72B). Results obtained with the use of membrane filters (MF) in the Illinois Public Health Laboratories (77B) correspond closely to results obtained with the standard hlPN procedure, but the MF technique permitted the examination of larger volumes of samples in shorter time. Measurement of E. coli Type I by the membrane filter ( 7 B ) was found to be faster and to have greater accuracy than the EC multitube procedure. Glass Fiber Media. A study of the continuous cleaning of fabric filter tubes (8B) by direction of controlled countercurrent pulses of compressed air into the clean air exit tube showed that the over-all performance, space requirement, and estimated yearly cost per c.f.m. for two types of collectors appeared to be in the same range. A colloidal graphite finish (3B) triples the endurance of silicone-treated glass filter bags used for cleaning hot gasses. Fiber glass dust collectors (7B) are receiving wide use throughout the cement industry to handle the dust emission from kilns. The result of a 14-month operation of a pilot unit indicated that the ability of silicone-treated glass fabric filter tubes (73B) to recover the dust from a zinc concentrate roasting plant was excellent. Efficiencies of 99+% were obtained during normal operation at 450” F. Filter Systems
A self-cleaning vertical pressure filter (73C) containing braided filter tubes is used to remove solids from dry cleaning fluids. Backwashing shortens and widens the tube, shearing off the filter cake. A nonclogging automatic pressure filter (7C) will clarify solutions containing particles as small as 0.1
micron. The filter tubes are fabricated by wrapping fine stainless steel wire over a stainless perforated core using epoxy resin to bind the wire to the tube. A percolation filter and complete flow chart is described for the finish refining of lubricating oils and other fractions (7C). Fullers earth is favored over bauxite as the adsorbent medium for heavy decolorization requirements. Another flow chart describes the continuous contact filtration process for solvent extracted acid wash lubricating oils which may also be applied to the finishing of waxes and specialty oils (6C). Cartridge filters or coalescers (74C) are used for separating both solid and liquid contaminants from liquids. I n another article, an in-line filter unit containing one, four, ten, and sixteen filter inserts ranging in area from 4.2 to 67.0 square feet uses any filter cloth (5C). Cyclone filters (77C) are efficient, inexpensive to maintain and eliminate risk of dumping accumulated debris. A packaged water filter treatment plant, factory assembled, (3C) is designed for traveling. A low temperature filtration device developed for the purification of crude nitrogen trifluoride is very useful for similar applications (15C). A South African cannery (4C) finds that a tubular filter chamber of the candle type is economical, efficient, and clean in sugar-syrup filtrations. Inadequate filtration (70C) is probably the greatest source of trouble in hydraulic systems, and an important consideration is the location of the filter. Boeing (9C) has redesigned the jet aircraft hydraulics system. T h e Norad tunneling project has imposed a heavy dust load on automotive equipment (2C). Good preventive maintenance with air, oil, fuel, and water filters has lowered maintenance and replacement costs. Filter screens on plastic extrusion machines remove foreign particles. A special filter was designed to provide instantaneous filter screen changing (72C). At the Savannah River Laboratory (76C), a filtration system has been developed to contain radioactive steam and steam-air mixtures (fog) in the event of an accident. Water coolant loss by nuclear reactors can be caused by a leak in a filter system external to the reactor tank. T o eliminate this danger, a Sethco submerged filter system has been installed inside a noncritical water moderated reactor (782). New filter systems include Sharples automatic centrifugal filtration equipment, Adams Poro-Edge strainers, Sperry’s plywood plate-and-frame filters, Baker Perkins push type centrifugal filters, Bowser-Briggs Model 610-D diatomite filter with its star shaped element, and GoslinBirmingham rotary drum dryers. Tubular Filters
Characteristics of depth filters are described (70) with a candid discussion of their advantages and disadvantages for hydraulic systems. AUTHOR J . L. Englesberg is President of Sethco Manufacturing Corp., Merrick, L.I., N.Y.
NASA conducted extensive tests on the pre-cleaning of wire mesh filter elements (60) before putting them into service. The best cleaning method was found to be simultaneous solvent flushing and ultrasonic vibration. For long life and trouble-free performance of hydraulic-system components, the system fluid must be kept clean. Various types of tubular filters ( 4 0 ) are discussed and factors are explained in selecting the correct filter for a particular application. For servovalves to operate efficiently, contamination in the hydraulic system must be removed by filtration. Methods, materials, and designs are discussed (80). Fram’s new combination fuel filter and water separator ( 2 0 ) and a high performance oil filter are described. American Oil is installing filters ( 5 0 ) at all pumps. A textile sleeve in a filter has been replaced by a specially perforated stainless steel sheet (70). The modified filter has less tendency to clog, it is easier to backflush for cleaning, and it has a higher range of permissible operating temperatures. Stainless steel Type 304 water well filters (30) are used instead of carbon steel because of corrosion resistance and because one third more holes can be punched because of the greater strength of stainless steel. Pressure Filters
A pressurized horizontal tank filter with vertical leaves (2E) gives continuous filtration of toxic, volatile or corrosive material requiring complete enclosure during filtering and cleaning. Hercules horizontal plate filter called “Funda Processor” (523) is fully automated for process work rather than simple filtration alone. The need for scavenger plate operation has reappeared in many cases where pressure tank type filters are used (63). Bird continuous centrifuges and rotary drum filters (7E) are available in enclosures which meet code requirements for operation u p to 150 p.s.i.g. Continuous pressure filtration ( 3 E ) and adiabatic drying of sludge is a problem if a flocculating agent has been used and the sludge consists of low density flocs with a high percentage of water. The sewage sludge dewatering plant of the city of Sheffield, England (4E), is reported to be the world’s largest. Vacuum Filters
T h e new causticizing system using an Eimco continuous belt clarifier-washer (5F) clarifies white liquor direct from the causticizer tanks thereby eliminating the need for the white liquor clarifier. Reputed to be the world’s largest, an Eimco rotary vacuum filter (4F) 8 ft. in diameter by 20 ft. long was installed by A. F. Murch Co. for filtering juice concentrates. It handles 5000 gal. per hr. of juice in a 36-hour cycle. Dorr-Oliver reports ( 7F) that their rotary-vacuum drum and disk filter are now available with standard interchangeable parts, permitting quick field conversion. Continuous Eimco vacuum filter equipment contained in pressure vessels ( 2 F ) is being applied to an increasing number of slurries of hazardous materials. VOL. 5 6
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Two Eimco string discharge filters handle barium carbonate slurry at Laport Industries Ltd. in England (3F) Radioisotopes in Filtration
A radioisotope gauge is employed to measure the density of a magnetite slurry (filter feed solids) without coming in contact with the slurry (4G). This automatic system has reduced the operators duties. Filter paper produced for use in automobile oil filters is evaluated using radioactivated carbonyl iron particles (ZG, 3G). Data concerning the relative response of different papers to changes in flow rate, particle-size distribution, and contaminant level can be taken rapidly and at low cost. The data so obtained can be used to compare papers. Radioactive tracers show great promise for studying filters (9G). Test filters were evaluated on the basis of the weight of contaminant trapped in cartridge filters downstream of the test filter. For removing strontium-90 from milk, gel filtration using “Sephadex” without acidification is possible (5G). Filtration Miscellaneous
By means of an IBM 709 computer (ZH)optimum operating conditions were found for 3-stage sand filters at Phillips’ Ambrosia Mill uranium operation. Comparison in cost ( 4 H ) of a vacuum filter fabricated in reinforced polyester, elastomer lined steel, and Hastelloy C shows elastomer lined steel to be 80% more expensive and Hastelloy C to be 300y0 more expensive than reinforced polyester. Penton cladding ( 3 H ) of filter press plates and frames extends their life to 10 years. Potable Water Filtration
Sand Filters. The design and construction of rapid sand gravity filters (21) from the viewpoint of a filter equipment manufacturer emphasize design for higher flow rates especially when the water is used for industrial applications. Russian improvements in rapid sand filtration (61) include flow of water in direction of diminishing size of sand grains, double-layer filters, and coagulation just prior to rapid sand filtration. Innovations in filtration practice in the Netherlands, Western Europe, and in Russia (71) are chiefly concerned with the centeredoutlet filter. This filter is based on a double flow (from the top of the bed downward, and from the bottom of the bed upward), toward a common collector system located within the bed. High flow rates are claimed. In addition the downward flow through the upper portion of the bed applies a downward pressure on the top of the bed thereby preventing excessive expansion of the bed and breakthrough at the relatively high upflow rates employed in the lower portion. The submerged filter at the St. Louis County Water Co., South County Plant (41),which serves as the treatment basin take-off system, has improved treatment basin velocities and sedimentation, and in general has resulted in a very substantial saving in plant construction costs. The essential advantages in the automatic valveless gravity sand filter have been described ( S I ) , 68
INDUSTRIAL A N D E N G I N E E R I N G CHEMISTRY
The proper management, maintenance, and operation of sand filters have been described in several articles
(71,31,81-721). Diatomite Filters. Interest in diatomite filtration of potable water ( 5 J ) has led to better understanding of the physical phenomena involved. The editors of Water Works Engineering devoted a special section to this topic. Diatomite filters become unsatisfactory when raw water turbidity exceeds 5 units at filter rates between 1 and 2 gal. per min. per square foot ( 8 J ) . More diatomite filters fail from inadequate body-feed systems than from any other cause ( I J ) . Pilot filter tests should be run before the plant is designed. A method for finding the optimum economical design ( 2 J ) for a municipal diatomite filter plant is demonstrated for three cities of different sizes and with waters of three iron concentrations. Cost of operation is the same as for sand filters while clarity is better ( 7 J ) . Two newly developed diatomite filtration methods by Johns-Manville ( 6 . 4 , one using an alkali addition and the other substituting calcined magnesite for the alkali, remove 10 p.p.m. of iron from well water to produce a finished water containing less than 0.1 p.p.m. The use of diatomite filters for iron removal was found feasible both practically and economically (54. They will also remove manganese but with shorter runs. An interesting discussion by J. Hem on the effect of oxidation potential and p H in oxidizing iron and manganese and keeping them oxidized indicates that stronger oxidants than air, for example chlorine or permanganate, should be used. Condensate filtration, an accepted refinement in water treatment for high pressure utility company boilers, is now proving practical in industrial plants (3J). Pilot plant studies in the field demonstrate that tubular filters using filter aid remove 80-90% of iron and 40-6070 (undissolved portion) of copper. Microstrahers. Microstraining is a form of simple filtration ( 3 K ) . The original application of microstraining was the primary clarification of water prior to slow or rapid sand filtration. It can also be used under certain conditions as the sole means of filtration of both public and industrial water supplies. The process involves passing water through a revolving drum strainer covered with a fine stainless steel fabric. Experience with microstraining is described in three articles ( I K , 2K, 4K). Processes
Flocculation, Sedimentation, a n d pH Control. It is an axiom that the safety and potability of water increase with the degree of clarity. Turbidity that passes through the filter system may contain not simply the comparatively unobjectionable clay particles but also much material that is obnoxious and even dangerous to public health, as for example virus containing hepatitis and chemical pesticides and fertilizers. The never ending search for improved quality of water effluent (4L) puts more and more emphasis on
polyelectrolyte coagulants. The use of a polyelectrolyte (2L) in dosages of 10-30 p.p.b. under certain conditions will effectively decrease turbidity of effluent waters. The Microfloc process (6L),is equally adaptable to rapid sand gravity and pressure filters and will produce water having a clarity better than distilled water. Increased filtration efficiency (5L) was found to correlate well with increasing electrophoretic mobility of SUSpended clay particles. The City of San Diego, Calif., used slaked lime to treat its Colorado River water (3L). By purchasing a lime recalciner plant it disposed of its sludge disposal problem and saved $5.00 per ton on softening lime. I n the Netherlands it is necessary to reduce iron content in ground water from 1-10 mg. per liter to less than 0.1 mg. per liter (7L). Because of other contaminants such as humic acids, simple aeration and subsequent filtration no longer reduced the iron content down to satisfactory levels. The prevention of sol particles during aeration was found to be the best answer. T o combat algae loading filters (7L)a presettling basin was constructed at Oshkosh, Wis., and copper sulfate is pumped into the intake pipe as water enters the basin. Activated Carbon. Selection of the location for activated carbon treating of a water supply ( 2 M )depends upon whether chemicals added to the water to alter pH or for disinfection render taste and odor compounds less or more adsorbable. Synthetic industrial and agricultural chemicals, some toxic, become water borne and affect plant, fish, and human life. The problem of identifying and determining the organic materials in surface waters by means of activated carbon has been standardized by the USPHS. Low values of concentration of the contaminant and flow rate through the apparatus gave best results ( 3 M ) . Data and operating experiences from several granular carbon installations in handling potable water show proved ability to produce odor-free water, ability to remove solids, ease of operation, and self-adjustment to changing loads ( 7 M ) . Coliform and Virus Control. Dewatering a sewage sludge by a vacuum filter process is a relatively new practice in this country. A study was made (3N)to determine the degree of coliform elimination during treatment and storage of the sludge. Future studies recommended ( 7 N ) for killing of waterborne viruses are the effect of lime softening as well as treatment with activated carbon. Pilot water plant studies ( 2 N ) showed complete polio virus death only if the water was previously flocculated. Erratic results were obtained through rapid flocculation-filtration procedures.
(30) by instrumentation in the new Wyandotte settling units has increased filter capacity 25%. The treatment of surface water in England is becoming more complex due to contamination by industrial impurities. An increasing use of automation (20) in the handling of wet and dry chemicals, settling tanks, filtration, automatic washing, chemical dosing and signaling has been the result. The chemical handling in Chicago’s Central District Plant (60)from receipt to application is tied into a working unit by an extensive network of instrumentation and controls. In the event of failure of any of the control equipment switching over to spares or manual operation is a simple changeover. The new filtration plant for Troy, N. Y . (50), incorporates multiple-use instrumentation for all filters, chemical feed control from a central console, and automatic filter backwash. Plants
Present-day water works filter trends are toward higher unit rates of operation (78P). T o offset deterioration of effluent quality by inherent surging, the control systems must provide stable performance. The trend is also toward centralization of operation with automatic backwash of filters. Control systems and components are available to provide the degree of stability needed. Another trend (74P)in the design of water treatment plants is to provide better flocculation and sedimentation facilities to pretreat the raw water so that the filter can be operated at a higher rate. Rapid sand filters are also undergoing changes with coarser sand and combination of anthracite and sand for higher filtration rates. Water research at the Iowa State University (2P)has been directed toward providing the engineer with information which will be useful in design. Research is being conducted in three areas: rapid sand filtration, diatomite filtration, and treatment and disinfection of small water supplies. Several designs for entire water filtration plants (7P) that depart from convention are described and unusual approaches to the design of some of the elements of a treatment plant are examined. The results of a study (7P)on the effect of filtration rate changes on quality should be of interest in filter design and operation. A discussion of the cost principles involved in the design of diatomite filters (3P)applies to both potable water for municipalities and industry and to the filtration of water in swimming pools. Case histories of plant construction, operation, and improvement are contained in other references (4P-6P,
SP, llP-73P, 15P, 76P,19P,2OP). Percolating or trickling filters (9P)are being successfully used for the treatment of food product wastes.
instrumentation
REFERENCES
Chemical dehumidification systems using lithium chloride ( 4 0 ) in two Philadelphia water filtration plants protect automatic controls and reduce maintenance. Butterfly valve actuators (70) are discussed for water and sewage filtration plant service. Turbidity control
Filter Theory (1A) Baumann, E., Cleasby, J., LaFrenz, R., Am. Water Works Assoc. J . 54, 1109-19 (Sept. 1962). (2A) Baumann, E., Oulman, C., Am. Water Works Assoc. . I 56, . 330-2 (Mar. 1964). (3A) Chem Eng. News 41, 45 (8 July 1963). (4A) Cleasby, J., Baumann, E., Am. Water Works Assoc. J . 54, 579-GO2 ( M a y 1962). (5A) Gertjejansen, R., Ta@i 47, 19-21 ( J a n . 1964). (6A) Gross, R. I., Hydraulic+ @ Pncumalics 18, 74 (Aug. 1963).
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(?A) Jahries, C. A,, Chem. Eng. 70, 237-40 (11 Nov. 1963). (SA) Klein, I,, Hydrocarbon Process. Petrol. R e f i n ~ r42, 137-40 (Jan. 1963). (9A) LaFrenz, R., Baumann, E,, A m . Water Works Asroc. J. 54, 847-51 (July 1962). (10A) .Martin, G., Chem. Eng. 70, 103-6 (21 Jan. 1963). (11A) Mcyer, H., Toppi 41, 296-310 (April 1962). ( 1 2 4 Patel, V. J. and others, American Society of Chem. Eng. 90, No. SM2 Parr I : 87-100 (Mar. 1964). (13.4) Piller, F., Shirato, M., A.1.Ch.E. J. 10, 61-6’7 (Jan. 1964). (14.4) Prod. E n g . 34, 86-7D (9 Dec. 1963). ( 1 3 ) Sharbaugh, J. C., Chem. E r g , 69, 153-8 (10 Dec. 1962). (16A) Shirato, M . a n d others, A.I.Ch.E. J. 9, 599-605 (Sept. 1963). (17.4) Tiller, F. M.,Cooper, Harrison, A.Z.Ch.E. J.8, No. 4, 445-9 (Sept. 1962). (18.4) LVheeler, H. L., Hydraulics @ Pneumatics 15, 84-5 (Nov. 1962). (19A) Ibid., 16, 102-4 (Apr. 1963). Filter Media; Filter Aids (1B) Ballard, W. E., Rock Prod. 6 5 , 60-3+ (Oct. 1962). (2B) Cahn, L., Mater. Res. Std. 3, 377 (May 1963). (3B) Chem. Eng. 69, 92 (12 Nov. 1962). (4B) Ibid., 71, 62 (17 Feb. 1964). (5B) Chem. Eng. Hews 41, 48-9 (2 Dec. 1962). (6B) Ibid., 41, 45 (27 M a y 1963). (7B) Delaney, J. E. and others, W a t e r Sewage Works 109, 289-94 (Aug. 1962). (8B) Dennis, R., Silverman, L., A S H R E A J. 4, 43-52 (Iviarch 1962). (9B) Dick, G. A,, Mining Congr. J. 49, 31-34 (Aug. 1963). (10B) French, R.: Chem. Eng. 70, 177-92 (14 Oct. 1963). (11B) Herod, B., Pit t 3 Quarry 55, 96-101 (Aug. 1962). (12B) Hoffman, D . A . and others, Water Pollutron Control Federation J. 36, 109-17 (Jan. 1964). (13B) Landucci, L. P., Eyre, R. E., Can. Insl. o j Mining and .Mela/lrirgy 6 5 , 337-40 (April 1962). (14B) Lawler, F. K., Food Eng. 35, 45-7 (Dec. 1963). (l5B) Machine Design 36, 12 ( 2 July 1964). (16B) M a t e r . Design Eng. 57, 93 (May 1963). (17B) McCaffrey, J., A m . Water Works Asroc. J . 5 5 , 560-4 ( h l a y 1963). (18B) 011 Gas J.GO, 118-19 (2 July 1962). (19B) Petrol. Eng. 34, 90 (Aug. 1962). (20B) Powers, J,, Research/Deueiop. 14, 32-4 (June 1963). (21B) Rodman, C. A,: Staricenka, J. A,, Mech. Eng. 85, 54-7 (Feb. 1963). (22B) Sloane, H. J., Anal. Chem. 35, 1556-8 (Sept. 1963). (23B) Stapowick, H. E., Am. Perfumer B Cosmetics 78, 21-3 (July 1963). (24B) Varma, M. M., Sheffert, P. C., Mater. Res. Std. 3, 560-1 (July 1963). (25B) Winneherger, J. H. and others, Water Pollution Control Federation J . 35, 80?--13 (June 1963). (26B) Wrvtnowski, A , , Chem. Eng. Prog. 58, 61-7 (Dec. 1962). Filter Systems ( l C ) Chem. Eng. 69, 112 (12 h’ov. 1962). (2C) Diesel Equipment S u p . 40, 21 (March 1962). (3C) Eng. News-Record 172, 50 (5 March 1964). (4C) Food Eng. 34, 130 (May 1962). (5C) Food Technol. 16, 35 (Dec. 1962). (6C) Hydrocarbon Process. B Petrol. Rejiner 41, 205 (Sept. 1962). ( ? C ) Hydrocarbon Processtng B Pet. Rejiner 41, 219 (Sept. 1962). (8C) Kvlodney, M., Chem. Eng. Dept., College of the City of New Yvrk, personal communication, Der. 1963. (9C) Lesser, R . H., S.A.E. J.71, 73-74 (Jan. 1963). (lOC) hiathe, J. A , , Plant En,?. 16, 131-4 (Nov. 1962). (11C) Oii Gas J . 60, 74 (31 Dec. 1962). (12C) Plastics World 22, 24 (Jan. 1964). (13C) Prod. Eiig. 33, 72 (5 hlarch 1962). (14C) Redmon, 0. C., Ckem. Eng. Prog. 59, 87-90 (Sepr. 1963). (15C) Schoenfelder, C. W., J . Sci. Inrtr. 39, 88 (Feb. 1962). (16C) IValker, J. LV,, Peters, A. H., Itiech. Eng. 8 5 , 46-50 (Sept. 1964). T u b u l a r Filters (1D) Davis, H. D . , Hydraulics @ Pneumatics 16, 77-9 (I\iarch 1963). (2D) Diesel Experiment Sup. 41, 44 (Nov. 1963). (3D) Engineering 194, 51 (13 July 1962). (4D) Engstrom, A . H., Romeo, F., Machine Design 35, 227-31 (9 M a y 1963). (5D) Oil Gas J . 60, 75 (July 1962). (6D) Riehl, W. A,, Hawkins, C. E., Hydm~riicsG” Pneumatics 15, 68 (Feb. 1962). (7D) Sled 153, 59 (26 Aug. 1963). (ED) IVheeler, H. L., Sherril, E. A,, Hydraulics B Pneumatics 15, 111-14 (April 1962). P r e s s u r e Filters (1E) Amero, C. L., IND.Eso. CHEM.55, 40-43 (Oct. 1963). (2E) Chem. Enq. 70, 114 (14 Oct. 1963). (3E) Fluid Handling, 164, 305-7 (Sept. 1962); 165, 360-2 (Oct. 1963) (4E) Ibtd., 16.5, 319-27 (Sept. 1963). (5E) Food Eng. 35 96 (Dec. 1963). Chem. Eng. Prog. 59, 91-3 (hlay 1963) (6E) Jahreis, C.
A,,
V a c u u m Filters (IF) Chem. Eng. 70, 102 (16 Sept. 1963). (2F) Fleming, D. K.: Dahlstrom, D. A,, Chem. E y q . Pro,o. 59, 62-67 ( J d y 1963). (3F) Fluid Handling 165, 342-4 (Oct. 1963). (4F) Food Eng. 34,116 ( M a y 1962). (5F) Paper lndultry 44, 80-1 ( M a y 1962). Radioisotopes i n Filtration (1G) Brown, R. M.,Ross, J. M., Hydraulirs B Pneuniotics 15, 120-2 (Sept. 1962). (2G) Gruverman, I. J., .\icieonics 21, 70 (Dec. 1963).
70
I N D U S T R I A L A N D E N G I N E E R I N G CHEMISTRY
(3G) Rosenthal, F., Instr. Control Systems 35, 111-12 (April 1962). (4G) Sheary, G . W., Mzning Eng. 14, 50-2 (May 1962). (5G) Sirilan, S., Chem. Ind. (London) 1195-6 (20 July 1963). Filtration Miscellaneous Fluid Handling 15, 55-65 (Feb. 1964). Kohle, R . A., Goard, H. W’.,Chem. En!. Pro!. 58, 56-60 (Dec. 1962) Plaftics Technoi. 8, 66 (April 1962). Torres, A. F., IND.ENC. CHEM.56, 32-36 (June 1964).
(1H) (2H) (3H) (4H)
S a n d Filters (11) Becker, R . J., .4m. Wuter Works Arsoc. J . 55, 1157-64 (Sept. 1963). (21) Burton, J . W., Tappi 47, Sup: 157.4-161A (Jan. 1964). (31) Henderson, A. D., Water Works Eng. 116, 811 (Oct. 1963). (41) Hartung, J., Tuepker, J., Am. Water Work5 Arsoc. J. 55, 1165-73 (Scpt. 1963). (51) McKee, D., Am. Water Works Arsoc. J.54, 603-5 (May 1962). (61) Minz, D., Public Works 93, 212 (June 1962). (71) Smit, P., A m . Water Works Arsoc. J . 55, 804-6 (June 1963). (81) Symons, G . E., Water Works Eng. 116, 646 (Aug. 1963). (91) Thompson, W.J., Water Works Eng. 116, 38-9 (Jan. 1963). (101) Water Works Eng. 115, 358 ( M a y 1962). (111) IVoter Works Eng. 115, 502 (June 1962). (121) Water Works Eng. 116, (July 1963). Diatomite Filters (1J) (25) (35) (45) (55) (6J) (75) (8J)
Bell, G. R., A m . Water Works Assoc. J . 54, 1241-56 (Oct. 1962). Baumann, E., LaFrenz, R., Am. Water Works Arsoc. J. 5 5 , 48-58 ( J a n . 1963). Carr, H. E., Poaer 106, 65-7 (Dec. 1962). Coogan, G. J., Am. Water Works Assoc. J . 54, 1507-17 (Dec. 1962). Jackson, T. M., Water Works En,?. 116, 46, 113 (Jan.-Feb. 1963). Kollin, W., W a t e r fezcage Works 109, R 182 (30 Nov. 1962). Schultz, C. J., Pubiic Works 93, 116 (March 1962). Vrlde, T., Cramley, C., A m . Water Wotks Arroc. J . 54, 1493-506 (Dec. 1962).
Microstrainers
(1K) (2K) (3K) (4K)
Berry, A. E., Am. W a t e r Works Assoc. J. 53, 1503-8 (Dec. 1961). Carter, R . C. and others, A m . Water Works Asroc. J.54, 606-20 (May 1962). Evans, G. R,, Boucher, P.L., Water Sewage Works 109, R 184-9 (30 Nov. 1962) Jones,A. L., rV=!er WoiorkrEng. 116, 118 (Fcb. 1963).
Flocculation, Sedimentation a n d p H Control
(1L) (2L) (3L) (4L) (5L) (6L) (7L)
Fluid Handling 34, 231-33 (Aug. 1962). Am. W a t e r Works Arsoc. J.55, 597-601 (May 1963). Garnell, M., Graham, R . E., Water Works Eng. 115, 571 (July 1962). Harwood, R. M., A m . W a t e r Works Assoc. J . 55, 487-9 (April 1963). Jorden, R., Am. Water Works Arsoc. J. 55, 771-82 (June 1963). Rice, A. H., Conky, W. R., Toppi 47: Sup. 167A-171A (Jan. 1964). Stauss, J., Water Sewage Works 110: 267-8 (July 1963).
Activated C a r b o n (1M) Flentje, M . E., Hager, D. G., Wate, Sewage W o r k s 111, 76-9 (Feb. 1964). ( 2 M ) Hyndshaw, A , , Am. Water Works Assoc. J. 54, 91-98 (Jan. 1962). (3M) Rambow, C. A , , A m . Water W o r k s .hx.J.5 5 , 1037-43 (Aug. 1963). Coliform a n d Virus Control (lh-) Hartung, H., ,4m. Water Works Arsoc. J. 54, 1290-92 (Oct. 1962). (2N) Rvbeck and others, A m . Water Works Arsoc. J. 54, 1275-90 (Oct. 1962). (3N) Shook, W. M . and others, Water Sewage Works 109, 352-4 (Apr. 1962). Instrumentation (10) (20) (30) (40) (50) (60)
Brazaitis, A . J., ?Voter Sewage Works 109, 232-7 (June 1962). Griffiths, J. H. T., Fluid Handling 115, 47-54 (Feh. 1964). Hazey, G. J., W a t e r W o r k s Eng. 116, 175-7 (hiarch 1963). Parrvs, G. J., Publzc Works 94, 91 iFeb. 1963). Prendiville, P.. W o t e r W o r k s Waste Evg. 1, 80-1 ( h l a y 1964). Roth, hi., W a t e r Works Waste Eng. 1, 71-4 (May 1964).
Plants
(1P) (2P) (3P) (41’)
Am. Sac. C.E. Proc. 88 (SA No. 3127), 55-74 (May 1962).
Baumann, E. R., Oulman, C. S., Ct’nter Works Eng. 116, 366-68 ( M a y 1963). Bauman, E , and others, Water Sewage Works 111, 229-33 ( M a y 1964). Bozeman, H., Oil Gar J . 62, 92-4 (23 Mar. 1964). (5P) Chem. Eng. 70, 90-2 (13 May 1963). (6P) Cleasby, I. L., W’otalrr Works Eng. 115, 7 3 3 (Sept. 1962). (7P) Cleasby, J. and others, A m . Water Worki Assoc. J . 5 5 , 869-80 (July 1963). (8P) Crew, A , , Public Works 93, 68-71 (Dec. 1962). (9P) Fluid Hondlicig, 108, 22-8 (Jan. 1964). (1OP) Gardner, J. R., Stika. A . J., Public il’orks95, 109-110 (March 1964). (11P) Hanaon, L., Am. Water Works Assoc. J . 5 6 , 535-42 (May 1964). (12P) Jones, C. L,,,M h t e r Works Eng. 116, 488-90 (June 1963). (13P) Lawrence, R . L., IVoter Works Eng. 116, 956-8 (Dec. 1953). (14P) Ling, J. T., W o t e r Sewage Works 109, 315-19 (Aug. 1962). (15P) McDuniel, E,, Blair, T., A m . W a t e r W o r k s Assoc. J . 54, 1491-2 (Dec. 1962). (16P) Petrol. M a n a g m e n t 35, 197 (Dec. 1963). (17P) Robeck, G. and others, A m . FVoter Works Arsoc. J. 56, 198-213 (Fpb. 1964). (18P) Rogers, hi. E., Tappi47, Sup. 161.4-167.4 (Jan. 1964). (19P) Water Sewoge Works 109, 440-1 ( S o v . 1962). (20P) iVater Sewage M’orkr 109, 485-6 (Dec. 1962).
