•
EQUIPMENT RAW
SLUDGE
UNIFORM
0
2 7.
- 10%
FEED
SOLIDS
RATE
R O T O - PLU-~
ICKENER
SLUDGE
AT
This sludge concentrator, developed by Edco, is said to provide a low cost method cf dewatering primary sewage sludge, using a minimum of power and eliminating the need for chemical treatment
I I ! I I I j
EDCO COMPRESSION FILTER
neers say that the thickened sludge dis charged from the thickener is usually at 15% solids; it is discharged from the filter at 2 7 % solids. The concentrator will handle mix tures of raw and activated sludge or digested sludges. Typical mixtures of these sludges as fed to t h e concentra tor will range from 2.5 to 3.75% solids, according to the company. Edco says the concentrator requires only Vu h p . per ton of sludge (dry weight) per 24 hr., including the power involved in pumping the sludge to the unit. A concentrator handling 8 tons (dry weight) per 24 hr. will require a total of only 2 3 / 4 h p . Units are available in sizes for ca pacities from 1 ton (dry weight) p e r 24 hr. up to whatever capacity may be required. Company says the concentra tor requires a relatively small floor space; a unit handling 8 tons of sludge (dry weight) per 24 hr. requires an area 10 X 10 X 10 ft. high. Ε 1
Continuous Reactor For Chemicals UNIFORM OF AT
RETURN RAW
DISCHARGE
DEWATERED 27
%
RATE
SLUDGE
SOLIDS
TO
SEWAGE
Dewatering Sludge N e w sludge concentrator is economical; power re quirement is low. Avoids chemical coagulation A .
SLUDGE CONCENTRATOR, developed
by Equipment Development, is said to fill the need for a low cost method of dewatering primary sewage sludge. Company says the concentrator uses a minimum of power and eliminates the need for chemical treatment. The concentrator is composed of two separate units, a Roto-Plug Thickener and a Compression Filter; these two units operate in series with each other. A positive displacement p u m p feeds un thickened sludge to the thickener. Here t h e sludge enters a rotating cylin der formed from a specially designed filter medium. A portion of the liquor in the sludge filters through the medium leaving a deposit of partially dewatered sludge. As the cylinder rotates, the de posit rolls toward the lowest point in the cylinder and soon forms into a cylindrical mass, rolling at the bottom of the cylinder. As the mass of sludge rolls over the material that is continu 4116
C&EN
SEPT. 26,
955
ously being deposited on the medium, additional liquor is expelled and at the same time the dewatered deposit is picked off of the medium by adhesion to the rolling mass. As the rolling mass increases in size, due to the sludge it has picked u p , it reaches a maximum diameter and then distends in the direction of its axis. The end of the distending mass of sludge is continuously cut away by a flanged enclosure as it rotates, and then it falls free. Discharged sludge falls into the filter where it is further dewatered by action of special rotating elements creating mechanical pressure in contained com partments, against a free draining sur face. T h e sludge is then discharged in continuous sheets to a conveyor. The concentrator can operate on primary sludge as low as 2% solids and on up t o whatever the sedimentation chambers may deliver. Edco engi
A continuous reactor for the prep aration of organic chemicals has been developed in Kodak Research Labs. Company says the reactor has advan tages over usual laboratory batch proc ess equipment. It is simple and com pact. Because it enables a given reac tion to continue as long as starting materials are supplied and the end product is removed, it is claimed to offer possibilities for preparing consid erable quantities of a desired com pound. The reactor is relatively inexpensive, according to Kodak Research Labs. A laboratory-scale unit for a variety of re actions can b e built of standard glass ware and materials for less than $50. According to company, the continu ous reactor is designed so that chemi cals are in contact with hot surfaces for a much shorter time. As a result, com pany claims there are fewer side reac tions. This is said to provide bettci quality compounds before purification and, in many cases, higher yield. €2
• Flow controller, by Builders-Provi dence, comprises a Venturi metering section and a pressure recovery section, a power-actuated valve mechanism, and a pneumatic, hydraulic, or electric positioning control unit. Its cast iron body for working pressures u p to 125 p.s.i., has pressure-averaging annulus at inlet and closed annular chamber with multiple vents at throat. Accuracy is within ± 3 % ranging from 25 to 100% of maximum capacity. Ε3
Corrosioneering N e w s Quick facts about the services and equipment Pfaudler offers to help you Ç
~J reduce corrosion and processing cost.
Published by The Pfaudler Co., Rochester,
Ν. Υ.
N e w P W drive for agitator speeds from 60 to 340 R P M ! H e r e is new flexibility for y o u r l a b o ratory arid pilot plant operations. You can tackle a big variety of jobs w i t h a new drive now offered on r e actors u p to 100 gallons. It is the P f a u d l e r PW drive —a variable speed d r i v e which can be easily adjusted between 60 and 340 R P M . T h e P W drive is standard e q u i p m e n t on all Pfaudler reactors up to 100 gallons. It has constant speed sheaves, which can be a r r a n g e d to give six different speeds: 60, 90, 120. 175, 250 and 340 R P M . A s a n alternative, variable pitch sheaves may be supplied to provide quick, precise adjustment of speeds within t h e range 60 to 300 R P M .
Confidential tests, using your own product, will be conducted to get data on performance in this dryer-blender.
More power, too In the speed reducer, both the w o r m and gear are "full-throated" to i n crease t h e load carrying capacity of the gears. In brief, "throating" is the construction of gear teeth and w o r m in arc shapes, which fit together so t h a t there is a larger area of contact p e r tooth and a greater n u m b e r of t e e t h in contact. A s a result of this practice, gears in the standard Pfaudler PW drive are rated to carry up to 3.6 H.P. at 175 RPM, well beyond t h e capacities normally required in small reactors. You'll also find it easier to get at the top head, to connect supply lines, because the P W d r i v e is smaller and t h e motor is mounted above instead of alongside the drive. P a r t of the
Test your product free i n Pfaudler dryer-blender! For laboratories and pilot plants, new PW drive is supported high and out of the way, providing better access to top of reactor.
over-all space saving is in the smaller g e a r housing, another result of throated gear construction. Still a n o t h e r advantage is the extra quietness of this new drive. Because t h e gear teeth m a k e contact over an increased area, you get accurate meshing, without distortion. F o r more data about this versatile n e w drive, available on Pfaudler glassed steel, stainless steel or alloy reactors u p to 100 gallons, write for Bulletin 923.
Huée reactor sets n e w record in size T h i s is a 3,700-gallon glassed steel reactor, built for use as a polymerizer in a Ludwigshafen, G e r m a n y , polyvinyl chloride plant.
Designed to take internal pressure u p to 225 psi, it stands 17'4" high and is t h e largest high-pressure vessel of this type built by Pfaudler—too large, in fact, to be fabricated in Europe! I t was built at Rochester, Ν. Υ., using the corrosion resistance of glass p l u s the working strength of steel. This eliminated the extra expense of heavy alloy construction (the top h e a d is 1"%" thick), and provided the required protection against metallic contamination and adherence of the product. Dual r o t a r y seals and extra-rigid Pfaudler V R L H drive w e r e included as measures to maintain sealing u n d e r high pressures. P e r h a p s you h a v e a similar p r o b l e m that can b e solved by t h e s u r p r i s ingly versatile resources at Pfaudler. W r i t e us a b o u t it.
You can n o w get valuable i n f o r m a tion on t h e drying a n d blending of your specific product in Pfaxidler's glassed steel conical d r y e r - b l e n d e r . A test unit has b e e n made avail able in t h e Pfaudler laboratory, for conducting sample r u n s of pr-oducts sent in by chemical processors. F r e e of charge, a product will be tested a n d j a full report m a d e to you ox* y o u r observers as to the d r y i n g r e s u l t s of various processing conditions. Such test data m a y be infinitely useful to you in deciding to i m p r o v e your d r y i n g operations. In actual full-scale operation^ these g l a s s e d steel d r y e r - b l e n d e r s h a v e performed 1 in 7 hours, an a m o u n t of woirk for merly r e q u i r i n g 4 days. I Write for further details o n o u r d r y e r - b l e n d e r laboratory tests.
CAN YOU USE A GUARANTEE AGAINST CORROSION? An actual 12-month guarantee against corrosion is now being supplied with Pfaudler a-cidalkali - resistant glassed steel processing e q u i p m e n t for cer tain applications. This guaran tee provides for free on-the-spot repairs, or F.O.B. factory repairs to the vessel if it is rendereti. in operable by corrosion d u r i n g its first year after delivery. To learn more a b o u t the c o n ditions for which this u n i q u e guarantee is offered, and to> get help with your particular co>xrosion problem, write to: I>«pt. CEN9, T h e Pfaudler Co., Roch ester 3, Ν. Υ.
SEPT.
2 6.
1955
C&EN
4117
^tW-UQVIDS-CASCSSOLIDS-LIQUrOSOAStMWJOi
S T O J J 3$vo-soinor>«onos ·$ 3Svos«inonsàn5 "The
Versa tile
Desiccant"
DRY GASES for the
LABORATORY with the
EQUIPMENT r Canned rotor pump (model S series), by Chempump, are priced from $ 1 0 0 to $150 lower than their older but still available counterparts, the m o d e l C series. The new S series Chempumps utilize fabricated parts in thieir con struction which can bê clad with such metals as titanium, zirconium, and Hastelloy series metals, as well a s Monel, Carpenter 20, and various t y p e s of stainless previously available. Ε4 • Portable
DROITE LABORATORY GAS DRYING UNIT Constructed of glass and metal employing indicating DRIERITE.
dewpoint
indices-tor,
by
General Klectric, is designed for appli cations where only periodic checks of dew point are desired. The indicator determines the moisture content of a gas by measuring the temperature at which the moisture begins to condense. This is done b y cooling a mirror sur face and observing the temperature at which dew first forms. The dew point directly describes the water vapor con
tent of a gas. The indicator gives ac curate readings over the range of d e w point temperatures from ambient t o - 100° F. (0.0003% moisture by vol ume in air ) . Ε5 r Lower
cost a n g l e
disintegrator,
by
Rietz, occupies only 2 sq. ft. of floor space. The angled motor mount and motor, directly coupled to the disinte grator head and rotor, serve as a selfcontained base for the entire unit. Vari ous sized disintegrator heads are avail able with 4, 6, or 8 in. diameter stainless rotors, to operate on horse powers of from 2 to 25. Ε6
I !
I j
Further useful information o n E q u i p m e n t m e n t i o n e d is readily available Use handy
coupon
on page
4120
Literature on Request
W. A . H A M M O N D DRIERITE COMPANY
itillF
XENIA, O H I O
Π
THE PROBLEM:
PUMPING SULPHURIC
ACID
THE SOLUTION:
VANTON PLASTIC PUMP No stuffing box! No gasket ! No shaft seals!
A leading producer of welding gas had the problem of transferring con centrated sulphuric acid (93%) from storage to process tanks. The pump had t o operate 6 to 10 hours daily and deliver 10 gpm against a 15 ft. head. The answer was found in a Vanton "flex-i-liner" pump, model PX60, •with its polyethylene body Mock and hypalon flexible liner. If you're troubled with pumping corrosive or abrasive liquids and slur ries, get the facts on the Vanton "flex-i-liner." Catalog 55 on request.
VANTON P U M P A EQUIPMENT CORP. 2 0 1 S w e e t l a n d Ave. Hillside, N . J . division o f Cooper Alloy Corporation
L
4118
C&EN
SEPT. 2 6,
1955
m
UH^
Distributing Low Pressure Fluids Spray head, b y N. C. Stearns, i s said to b e universally adaptable for the even spray distribution of low pressure fluids from discharge pipes. Called Gyrospray, it provides a controlled spray o£ evenly divided fluid articles at pressures under 5 lb. per sq. in. It assures an even pattern of wetting from the center out, accord ing to company. Also, in co»oling towers the Gyrospray pattern will efficiently cover the width of a standard horizontal cooling section without water loss, and on vertical coils maxiiïium efficiency is gained by the use of dual baffle boards, according to Stearns. Permissible ambient temperature range, —50° to 250° F .
