streams by modern methods- and equipment

paper read at the Diamond Jubilee meeting of the AXERICAN CHEMICAL. SocImY in 1951. Today, tangible evidence is available to support this prediction...
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streams by modern methods- and equipment by Harold R. Murdock

offered a practical method for con- in stepwiee fashion, in producing hetverting spent cooking liquors into ter and cheaper wood pulps. The cheniicals for reuse in the digester. task of improving their methods was the pulp and paper industry to a mat- Today this method is vital foi eco- relatively easy for the kraft pulp proter of little importance. This state- noniic operation. On the othei hand, ducers, r h o needed only available ment was niade by the w i t e r in a the sulfite process has nerer had an materials of construction. The dpaper read a t the Diamond Jubilee economical means for reclaiming or fite piilp producers, however. required meeting of the AXERICANCHEMICAL even a satisfactory means foi disposing special stainless steels and other acidSocImY in 1951. Today, tangible of sulfite waste liquor. Yeais ago, resistant materials which were then evidence is available to support this nobody bothered pulp inills about almost unknon n to industry. Rut prediction. Process competition, downstream nater conditions, so theie even more important, the kraft propalong with its companion economics, was little incentive to make capital ess contained a pioved means of eventually always brings abatement in investment in chemical recovery equip- complete cycling to process qpent pollution from industrial wastes. ment beyond the point dictated by cooking liquors into reusable pulping There are two major chemical proc- economics and competition. TJTater chemicds. Only more efficient nieans esses used in industry today for con- was abundant and stream pollution for collecting, evaporating, and burnversion of wood to cellulose fibers. w-8- an inipractical subject foi discus- ing the spent liquor were needed. Incentire to make such changes origiThe older.niethod is called the sulfite sion. I n the eaily thirties. coiisuiiiei de- nated fioiii economics rather than process because calcium sulfite and free sulfur dioxide are the active mand for better qualities in wood pulp from a desire to abate pollution. In chemicals in the cooking process. necessitated that producing companies the sulfite pulp industry, no practical The other method, known as the kraft examine their processes carefully. By means existed for the recovery of wlor sulfate process, derives the name experimentation in the mills, togethei fite n aste for reuse in the process and sulfate from the make-up chemical, n ith cooperation from equipment materials of construction for handling sodium sulfate. The term “kraft” manufacturers, pulp milk succeeded, the corroske n-aste were expensive. means strong pulps. C o n s e q u e n t l y , sulfite Figure 1 shows the propulp producers f o u n d no justifiable economiduction capacity of the U. S. wood pulp industry cal reason for proceming their waste liquors. from 1935 to 1955. New mills contemplated or The growth of many under construction are industries during and included in the chart. following World ’Kar I1 The difference in growth created increasing pollubetween sulfate and sultion loads, which soon fite capacity is signififorced governmental cant. Sulfite capacity agencies to demand correction of water polluhas stood practically tion. The sulfite producconstant while sulfate ers were in a quandary. capacity has shown treniendous growth. There Deiiiand for wood pulp became tremendous, are several conditions but since they had no which may explain this difference, but certainly p r o v e d m e t h o d for n-aste disposal it was stream pollution is one folly to expand the of the important reasons existing mills or build w h y sulfite c a p a c i t y has not moved forward new sulfite mills unless the location permitted during t h e p a s t t w o decades of i n s a t i a b l e f1 eedoni to discharge all the waste wlfite Figure 1. Wood Pulp Production Capacity of demand for pulp. United States liquor directly into the From its inception, streams. the kraft process has * Includes defibrated, exploded, remichemical, and screenings N ANOTHER

decade, modern methods

I and well-designed equipment will have reduced stream pollution from

102 A

INDUSTRIAL A N D E N G I N E E R I N G CHEMISTRY

Vol. 45, Ne. 11

1. low initial c o s t - A substantial saving in basic sweetening equipment is possible if you are starting from scratch to use Du Pont Antioxidant No. 2 2 . However, if existing equipment is to be employed you will benefit by2. low r e v a m p i n g cost-Because antioxidant sweetening is a simple procedure, the cost of revamping existing equipment is considerably cheaper than when treating agents, other than Antioxidant No. 2 2 , are used. 3. lower o p e r a t i n g costs-While operating costs vary with treating methods the use of Antioxidant No. 2 2 reduces the need for additional chemicals and reduces regeneration expenses. 4. No u n d e s i r a b l e chemicals-Since Antioxidant No. 2 2 sweetening does not require the use of sulfur or copper, the chances of reduced efficiency of additives resulting from these elements in the gasoline is eliminated unless they originate from some other source. A n t i o x i d a n t a n d s w e e t e n i n g a g e n t combined-These 5. two qualities are available in the single, inexpensive operation of adding DuPont Antioxidant No. 2 2 to your stocks. o c t a n e loss-With some sweetening 6. No g a s o l i n e loss-no methods there is a definite gasoline loss during processing; in other cases there is a loss in octane number. There is no loss of gasoline or octane number with D u P o n t Antioxidant No. 2 2 .

DUPONT ANTIOXIDANT No. 2 2 DuPont

Antioxidant

secondary

No.

22

i s N:N’-di-

butyl-para-phenylenediamine.

Since different gasoline stocks vary widely in their response to antioxidant sweetening, additional information on the advantages and

application of

this

process to

your

stocks i s available through any DuPont Petroleum Chemicals Division representative.

6etter things for Better living through Chemistry

.. .

Petroleum Chemicals ........................................................ E. 1. DU PONT DE NEMOURS & COMPANY (INC.) Petroleum Chemicals Division

Wifmington 98, Delaware

N E W YORK, N. Y.-1270 Ave. of the Americas.. .Phone COlumbur 5-3620 CHICAGO, ILL.-8 So. Michigan Blvd.. Phone RAndolph 6-8630 TULSA, 0KLA.-1811 So. Baltimore A v e n u e . . ..Phone Tulsa 5 - 5 5 7 8 .Phone PReston 2857 HOUSTON, T E X A S - 7 0 5 Bonk of Commerce Bldg.. LOS ANGELES, CALIF.-612 So. Flower S t . . .Phone MAdison 1691

......... . .. . . .. . . . . . .. .

IN CANADA: Canadian Industries Limited-Toronto, 0nt.-Montreal, Que.-Colgary, Alto. OTHER COUNTRIES: Petroleum Chemicals Export-Nemoun Bldg., 6539-Wilmington 98, Del.

---________________------------------------------------November

1953

I N D U S T R I A L AND ENGINEERING CHEMISTRY

103 A

Industrial Wastes Regiorial and local studies ~ w r c made to solye this acute problem. Aifirst the situation seemed inextricable, for suitable materials of construction were not available, but toda,y, as tlic result of reseai,c:h, the sulfite industry has a selection of various means for disposal of sulfite waste liquor if it ticsires to use them. K e shall ment,ioii a few of those developments which arc in cvmmiercisl operation today in oiic or more sulfite mills. First' let u s look a t the magnitude of the prohlein and the chemical nature of Dhe waste. Table I shows the soluble wood subst'atace and cooking cheniicals present] in R single day's produc,tion of sulfite waste liquor in thc United States. The collected liquor is based upon 7Oy0 recovery of tlic total licpiot, leaving the digesters.

processir v

t a n k production

off its feed?

Table 1. Soluble Wood Substance and Cooking Chemicals in U. S. Sulfite Waste liquor

\Vlicn the appctitc lor nvork of' your heating and cooling processes dinzinislies, the trouble may well be coil-ilis. Poi*, downtime due to pipe failures and liniit a t'lolls call swiously delay your production flow. Swi tch to Pla tccoils, the iicw tonic f o r production, a s revolutionary as the m i \ \vender drugs. Platccoils take 50 70 less tank space leaving more rooin for grcater payload. They heat o r cool 5 0 % faster. 'They simplify maintenance a n d sa\'c hours of dovmtirnr, Eqiially important, Platecoils cost as 111 ucli as 50% less in the first place. Platecoils cure production troubles involving lwat transfer and give production a shot i n the aim.

I PLATECOILS ELIMINATE

A 6.TO.8 HOUR-A-DAY

CHIPPING JOB

Write for Bulletin P75 today!

(Ba\ii

I,.

Wood siipnw

Lignins, gime

1

At Sealed Power Corp., installation of Platecoils has completely eliminated a 6-to-8 hour-a-day chipping job. Three Platecoils now heat a tank that previously took 4 pipe coils. Ask about Qther case histories.

REPLACES PIPE COILS

Coil-itis - Diagnosed as tank heatin and cooling p r o b ems. Platecoils - t h e m e -

7

9000 tons pulp a n d 34,000,000 g a l ~ a d liquor e from digesters) Weak l'otal ('ollected Strong Liquor t o PPI 1.lquor St_ream. ,pas, ions inns L ons etr.

1,400 8,600

?E

600 2,400

300

2,000 8,000 tf?!?

Coliectetl liquor is obtained hj, a inxiwhich sirriulates kraft mill practice, except that expensive shinless steel a11G other acidproof materials are esseiitial For practical performance.

steel rot8aryva,ciiiini washers suspenilrd ovei' aonci.ete vat's which are lined with ilcirlproof tile. The wash water floivs c ~ o u n t e t ~ c ~ ut ~ o ~the ~ e flow r ~ t of pulp8 so t'hat tlie filtrate leaving the dischai,ges f r n t r i that xasher receives the pulp and liquor sus1)ciirion tliscliitrged from the digest)ers. 1Jtiliaatioii of wood sugars has w(*eive(l attention from some siilfitc mills. 'L'liree mills have ronstrwtctl etlij.1 alcohol plants and two Kircwisill siilfit,c! rtiills have erected t'ot,iil:i. t plants which are siificiriit, to desrigar all their siilfite I' protluc:tion. The wsidiial ligriiii liquor then (:an be processed 1 ) ~ hiimirig iii specially designed fm.naws to produce steam for processing. It has been impossible to evapm'wlc

Avoid losing money on chemical-resistant clothing If DYNEL Garment-Life is greater than Test DYNEL garments under your own conditions..

.

Present Garment Life X Cost of DYNEL Cost of Present Garment then you are losing money on your present industrial clothing!

Wherever work garments deteriorate from exposure to chemi-

cals DYNEL offers economy-in coveralls, jackets, trousers, and socks. Available in a range of weights and constructions suited to varying working conditions-indoors or out, hot or cold. Your choice of attractive solid shades.

DYNEL'S superior performance 1. Unaffected b y most chemicals 2. Strong-wet or dry 3. High abrasion resistance 4. Washable-won't shrink or stretch 5. Long laundry life 6. Will not support combustion 7. M a y be cleaned or decontaminated in acids without harm

WRITE on

business stationery for your copy of Bulletin S-147.

TABER PUMP CO. (Est. 1859) 294 ELM ST.

BUFFALO 3, N. Y.

1

cuts costs!

20-hour Immersion tests prove

DYNEL'S amazing chemical resistance Write for results of 20-hour immersion tests in 57 different chernicals (acid:, bases, oxidizing agents, solvents), DYNEL industrial clothing, thanks to its built-in chemical resistance, has outworn clothing of other fibers in the same service by as much as 10 to 1. For a list of manufacturers of DYNEL industrial clothing, the DYNEL Chemical Resistance Folder, and complete data on Immersion Tests, write: Textile Fibers Dept., P1, Carbide and Carbon Chemicals Company, A Division of Union Carbide and Carbon Corp., 30 East 42nd St., New York 17, N. Y.

Performance will tell November 1953

. . . it's

INDUSTRIAL AND ENGINEERING CHEMISTRY

DYNEL

P

105 A

Industrial Wastes

it’

we

A RidHT TURN of the page and you’ll see why. It’s 36 feet long 9 foot diameter. ..it‘s type 304 stainless steel and it’s designed for storage of chemicals. It’s an example of BRIGHTON’S capacity to build BIG and to build RIGHT! Brighton .is one of the nation’s leading suppliers of all types a n d sizes of chemical process equipment.

-

BRIGHTON

If you would like to know more about Brighton and how you can get more for your money in chemical process equipment. write Dept. E for eomprehenrive bulletins.

.*

copper works inc, 820 slate ave

‘“ONS

est. 1914 engineers b metalsmiths machinists derlgners,

106 A

cincinnali 4 e ahie

F C DECKEBACH SONS CO., HAMILTON COPPER 6 BRASS WORKS, BUCYRJS KETTLE WORKS

producers of chemical processing equipment

centrations of 65% desired for furnace incineration, because scaling of the heat exchanger surfaces by calcium is persistent. The industry has had t o await technological developments in evaporator design. The problem was ponderable until a design was conceived which permits the operator t o switch the steam and liquor from one side to the other side of the heat exchanger surface, so that the steam may soften and scour off the lime deposits before they have a chance to harden as scale. Two mills have now installed these unique evaporators, which can handle either desugared OP straightrun sulfite waste liquor. Careful attention has been given to the design of a furnace and steam boiler which will burn the concentrated sulfite waste liquor and give a reasonable return on the investment. If the cooking chemicals could also be recovered, in addition to the heat from burning the soluble wood substances in the liquor, then the economics of the recovery n-ould be improved substantially. The kraft process has such advantages and so does the magnesiabase sulfite mill of Weyerhaeuser Timber Co. at Longview, Wash., where, by burning the waste liquors in a heat recovery system, both magnesia and sulfur are scrubbed from the gases for reuse in the process. Of outstanding interest is the ammonium-base pulping operations of Crown Zellerbach Gorp. Such waste liquors have been found to change on heating. The ammonia, lignin sulfonates, and sugars all appear to condense to larger molecular structures with different characteristics. The properties of these condensation products suggest many applications. If in the quest to find better means to utilize lignin sulfonates, which compose over 60% of sulfite waste liquors, new compounds such as the ammonium lignin condensate are found, they could create an economic return that might turn sulfite pulp production sharply upward. It clearly appears that both kraft and sulfite gulp mills are reducing their pollution load on streams by modern methods and well-designed equipment. Process competition will be a driving force toward such an end. Garrespondenoe concerning this column will be forwarded promptly if addressed to the author. % Editor. INDUSTRXAL AND ENGINEERINQ CBBMHBTRY, ll5b---16%hBt., N.W., Washington 6, D. 6.

INDUSTRIAL AND ENGINEERING CHEMISTRY

Vol. 45, No. 1 1

For 100% Effective REMOVAL and RECOVERY of DUST and DRY MATERIALSanywhere in your plant 1

See the

‘THEM SHOW” Be sure to see PREMIER’S two n e w dispersators a t the ‘Chem Show‘the Series 3200 (shown a t right) a n d the Series 2400 for 30 to 300 gallon batch a n d continuous mixing. Both series meet tank and motor closure requirements and have a complete range of electrical characteristics.

HOFFMAN lndustrial Pneumatic

Permanently piped, stationary systems that pick up where present collectors leave off! On process operations or plant cleaning, Hoffman-designed systems provide big capacity for central collection of dust from several areas at same time. Sizes from 3 to 100 H.P., or larger to your requirements. Engineering survey, without obligation. Write for technical Bul letin A-939.

HOFFMAN ALSO BUILDS HEAVY-DUTY INDUSTRIAL PORTABLE VACUUM CLEANERS 4 Sizes

See them at

BOOTH C-14 Philadelphia November 30 to December

5

The complete range of PREMIER Dispersators are now efficiently handling viscosities up to 15,000 cps. and above. They utilize rugged maintenance-free design features such as separate shaft support, flexible motor couplings, and ready interchangeability of DISPERSATOR heads. You can depend on PREMIER’S 30 years’ background experience in the intense mixing field for responsible recommendations and quality equipment. if you cannot

Series 3200 for closed tank with flange mounting.

attend the ‘Chern Show,’ write for

- Write for Bulletins

PREMIER MILL CORPORATION 1180

GENESEE ST., GENEVA, N. Y.

Series 2400 for channel mounting.

Intermediates

S y n t h e t i c Rubber

S y n t h e t i c Fibers

Resins, Solvents, S p e c i a l t y Oils

Vinyl P l a s t i c s

Low-cost acetylene. . for high-demand products Acetylene is fast pushing into the limelight as a base material for inaking organic chemicals. In stride with this activity, Luniinus makes available the Wulff Process for the production of high-purity low-cost acetylene from light hydrocarbons. There is much to recommend a plant utilizing the WuIff Process:

Lummus is prepared to design, engineer and build a Wulff Process plant to fit your acetylene scheme, We’d be pleased to team up with you.

L U M M U S

T H E 3 8 5

-

MADISON

H O U S T O N

N I N G E N G I N E E R S AND

I08 a

AVENUE,

C H I C A G O

CONSTRUCTORS

C O M P A N Y

NEW

L O N D O N

YORK

17,

P A R I S

N . Y . C A R A C A S

F O R THE PETROLEUM A N D CHEMICAL INDUSTRIES

INDUSTRIAL A N D ENGINEERING CHEMISTRY

Val. 45, No. 11