British Chemical Abstracts. B.-Applied Chemistry. June 10 and 17

BRITISH CHEMICAL ABSTRACTS

B.—APPLIED CHEMISTRY

JU N E 10 and 17, 1932.*

I.— GENERAL; PLANT; MACHINERY.

Fluctuating flow of heat in furnaces. R. J. Sa r- Ja n t (Trans. Ceram. Soc., 1932, 3 1 , 83—128).—In an experimental investigation into the flow of heat through furnace walls under practical conditions, the dimensions of walls, lagging, rate of heating, and ultimate soaking temp, have been varied. Curves are given showing the effect of these variations on the heat content of the wall and the rate of heat flow. These data have been correlated with theoretical expressions derived from the Fourier equation, and reasonable agreement was obtained. The nature and variation with experimental conditions of certain correction factors necessary to obtain this agree­

ment are explained. H. H. Ma c e y.

Heat exchangers in the chem ical industry. F. A.

M. Wu l f i n g h o f f (Cliem. Fabr., 1932, 81—84).—Petrol­

eum stills are described as an example of heat exchange with direct firing. Designs of heating coils and jackets are discussed. Desirable features for a heat exchanger are th a t any one section should be removable while the rest are working, th a t the elements should be short for ease of installation and repair, th a t parts should be standardised and stresses due to temp, changes mini­

mised. Corrosion and cleaning must be considered in design, in some applications. H eat exchangers handling hot and cold gases may be of tubular type or of plate type. Dust may have to be taken into account. The Ljungstrom recuperator consists of a rotating cylinder, the interior of which is divided into hot and cold sectors.

I t has great capacity relative to the space occupied.

I t is, however, difficult to keep gastight. C. Ir w i n.

Graphical method for determ ining pressure drop and heat transfer in pipes. R. A. Ba y a r d (Chem. Met.

Eng., 1932, 3 9 , 130—132).—A chart enables those quantities to be read for any fluid of which the sp. heat, heat conductivity, viscosity, and sp. gr. are known.

The frictional pressure-drop lines are based on Fenning’s formula. The chart also enables optimum size of pipe, cost of pipe and cost of pumping considered, to be read off, and linear velocity may be converted into gals, per rain. Air, oil, and water heat-transfer curves are given, together with other curves for any liquid. The same base-line is used as for pressure drop, as both are func­

tions of the Reynolds no. C. Ir w i n. E x a m i n a t i o n o f b o i l e r - f e e d a n d b o i l e r w a t e r s .

F. M. Wi e n i n g e r (Woch. Brau., 1932, 49, 91—95, 99—

102).—Full directions are given for the analytical control of water-softening plant, with special reference to the CaO and Na2C03 treatment, though others are dealt with. The harmful effects of silicate deposits, and the need for special attention t o the purity of the supply

t o high-pressure boilers, are emphasised. F. E . Da y.

Boiler slim e, a hitherto unrecognised source of danger. H. Ri c h t e r (Chem.-Ztg., 1932, 56, 173—174, 195).—When boiler feed-H20 is softened by the per- mutit process or by addition of Na2C03 or NajPO., there is always a small residual hardness which results in the production of slimes in the boiler; the NaHC03 and Na2C03 in the feed H 20 are hydrolysed at the high temp, and pressure in the boiler and the resulting bubbles of C02 coat or become attached to the particles of slime and these settle a t the ends of the boiler, around the seams and rivets, and along the tubes. The local high concn. of C02 has a marked corrosive action on Fe, which is converted into FeC03 with evolution of H 2.

The FeC03 eventually becomes oxidised and pptd. as Fe20 3, thus increasing the no. of slime particles and accelerating the corrosion. In addition the NaOH pro­

duced by hydrolysis of the Na2C03 produces caustic embrittlement of the weakest parts of the Fe and forms further crevices for the collection of C02 and slime.

Again, parts to which the slime adheres firmly, produc­

ing a protective coating, act anodically towards parts which remain relatively clean, and these latter are there­

fore subject to electrochemical corrosion. I t is suggested that these three actions are the cause of the severe local pitting often found in boilers ; the only remedy appears to be more frequent removal of slime, e.g., by opening the slime valve every 1—2 hr.

A. R. Po w e l l. Im provem ents in fuel econom y and steam gene­

ration. We i s s (Zellstoff u. Papier, 1932,1 2 ,153—159).

—The slag of lignite briquettes is less in quantity than that of coal, and severe corrosion of rnidfeather furnace walls occurs in consequence of the high temp. Repair costs have been reduced by cutting away the upper part of the midfeather, the wt. being taken by arches. The ash of lignite being basic in character, basic refractories should be chosen. Well grates are to be preferred.

Lignite gives rather better superheat than coal, and the fly-ash is less. Occasional removal of superheater tubes for cleaning with Na2C03 is recommended. Economisers with scrapers are not thought desirable ; it is better to clean occasionally with compressed air. Steam is not suitable, as it causes caking of the ash. Details of boiler trials are given. Automatic control of firing and lime- soda water softening are discussed. I n many cases the latter forms a means for a partial recovery of the heat in the blow-down water. C. Ir w i n.

Practical sun-still, serving also as a pyrohelio- m eter. T. Su z u k i and C. Ho r i e (J. Fuel Soc., Japan, 1932, 11, 23—24).—A still, which is described, has been used for measuring the H 20 distilled by solar energy.

D. K . Mo o r e.

* The rem ainder of this set of A bstracts will appear in next week’s issue.

483

B r itis h C h e m ic a l A b s tr a c ts —B .

4 8 4 Cl. I.— G e n e r a l ; P l a n t ; M a c h i n e r y .

Performance characteristics of cyclone dust collectors. L. C. Wh i t o n, j u n. (Chem. Met. Eng., 1932, 39, 150—151).—Dust cyclones working on coal fly-ash increase in collection with throughput, but the rate of increase gradually falls off with increasing gas vol. per min. Resistance also increases. For a given max. back­

pressure there is an optimum rate of throughput for any given group of cyclones, or, in other words, an optimum cyclone diam. Collection falls slowly with rising temp.

Results can be predicted only on the basis of trials as the fineness of the dust to be handled is usually an un­

known factor and is important. Increasing the diam. of the outlet pipe prevents dust being drawn back into the vortex, and rapid emptying of the cyclone is desirable.

C. Ir w i n.

Modern ball- and pebble-m ill technique. S. W.

Ke n d a l l(J. Oil & Col. Chem. Assoc. 1932,15, 66—93).—

The following types of ball mills are in use : (1) those with stone linings and balls, of which Belgian silex and Danish pebbles are the most satisfactory, (2) those with porcelain balls and linings, (3) cast-Fe or steel mills with cast Mn-Cr-Fe alloy or forged-steel balls (Brinell hardness should be 500). Tightly coiled, hardened steel spirals are efficient grinding media.

Mills over 3 ft. in diam. should be geared. Water- jacketed mills should be used for material sensitive to the slightest heating effect. Cylinders with the internal surface corrugated give increased efficiency.

Eccentric ball mills give more rapid grinding, but with increased power consumption. A modem development is the use of lifting bars parallel to the axis of the mill and spaced 12—24 in. apart and J— diam. from the internal surface of the cylinder. Rubber linings (usually 1 in. thick) when not affected chemically or dissolved by the material being ground last six times as long as 4-in. silex linings. Rexman balanced rod mills give increased grinding and reduced power consumption.

The smaller are the balls, subject to the limitation th at they do not float in the mixture being ground, the better is the grinding. For mills of the same diam., steel balls are more effective than pebbles. The working speed (formula given) should be such th at the balls are carried to the highest point of the mill, from which they cascade rapidly. The best grinding speed is th at requiring the max. power. The balls should occupy 45% of the vol. of the mill and the voids between the balls ( = 18% of the vol.) should be filled with the material (e.g., paint) being ground. In practice the material occupies 55—60% of the vol. to save handling charges. The working life of a lining is 10,000 hr. ; the wear on the balls varies from 1—3% for cast alloy to 20—30% for porcelain balls per 1000 hr.

D. K.. Moo b e.

The pachim eter, a machine for m easuring the shearing strength of plastic bodies. R. K. Sc h o­ f i e l d and G. W. S . Bl a i r (Trans. Ceram. Soc., 1932, 31, 79-82).-—A short cylinder of clay is rolled between two parallel horizontal planes (cf. B . , 1931, 676), and the min. pressure on the upper plane required to cause a permanent elongation of the specimen is measured.

H. H. Ma c e y.

Calculating washing efficiency in countercurrent décantation. M. T. Sa n d e r s (Chem. Met. Eng., 1 9 3 2 ,

39, 161—162).—For each washing vessel the liquid and dissolved solids entering and leaving are equated.

By solving these equations simultaneously an expression is obtained for the concn. of dissolved solids in the wth vessel in terms of known quantities, and then by sub­

stituting in the equation for this vessel, the loss of sol.

material in the sludge from the nth vessel is obtained.

Thus if the washing efficiency desired is known with the no. of vessels the quantity of wash-water required can be calc. By calculating this for varying nos. of vessels the most economical layout is obtained.

C . Ir w i n.

Apparatus for rapid m echanical crystallisation.

H. Ga b l e r and F. He b l e r (Chem. Fabr., 1932, 97—99).

—A double-walled trough is fitted with mechanical scrapers which keep crystals in motion. The jacket has water and steam connexions and cold compressed air is forced in at the bottom of the trough from a coil.

A current of cold air over the surface is maintained by an exhauster. The scrapers also serve for emptying the vessel when valves at the front are opened. The crystals fall upon a conveyor which transports them to a centrifuge. An apparatus occupying 20 sq. m.

will produce 1 |—2 tons of crystals at a time, and crystallisation is complete in 1—3 hr. The power con­

sumption is 3-75 kw. and the cooling-water requirement is 300 litres per hr. The crystals produced are finely

divided. C. Ir w i n.

Application of vacuum -cooling to continuous crystallisers. H. B. Ca l d w e l l (Chem. Met. Eng., 1932, 39, 133—135).—Vac.-cooling is unique in that it is not limited by the temp, of the cooling medium.

The avoidance of heat transfer through a solid wall from the solution removes many practical difficulties such as “ salting-up.” The first cost is much less, especially for corrosive solutions which under these conditions can often be handled in rubber-lined steel vessels.

Cooling below the temp, of the cooling water is effected by compressing the vapour leaving the crystalliser.

The use of this method for low temp, is, however, less economical than brine-cooling from an ice machine.

Salting-up of the crystalliser has been prevented by artificial circulation. “ Short circuiting ” due to failure of all the hot solution to reach the surface in the crystal­

liser, or to supersaturation, may cause difficulty and must be considered in design. When large vols. of solution are handled, 2- or 3-stage cooling is economical.

This method of procedure has been applied chiefly in the potash industry. I t is also feasible for the control of exothermic chemical reactions. C . Ir w i n.

Use of sm a ll coal.—See II. Apparatus for the essential oil industry etc.—See XX. D egassing H20 . —See X X III.

Pa t e n t s.

Air-cooled furnace w alls. Mo r g a n Cr u c i b l e Co.,

Lt d., and J. Wa l k e r (B.P. 369,413, 30.3.31).—Bricks with a recess on a face are used to construct walls with sinuous passages. B. M. Ve n a b l e s.

Heat exchanger. W. M. Cr o s s, Assr. to Ga s o l i n e Pr o d u c t s Co., In c. (U.S.P . 1,820,349, 25.8.31. Appl., 12.5.24).—A tubular exchanger heated by fire gases is provided with an arch of chequer-bricks over the

B r itis h C h e m ic a l A b s tr a c ts — B .

C l. I . —Ge n e r a l; P l a n t ; Ma c h i n e r y. 4 8 5

c o m b u s t i o n c h a m b e r ; t h e f i n n e d h o r i z o n t a l t u b e s a r e s i t u a t e d i n a n u p p e r c h a m b e r p r o v i d e d w i t h p r o j e c t i o n s o n t h e w a l l t o i n c r e a s e t h e r a d i a t i o n a n d t o d e f l e c t t h e g a s e s i n t o e f f e c t i v e c o n t a c t . B. M. Ve n a b l e s.

Furnace heat-exchange apparatus. R . S. Ri l e y,

Assr. to Ai r Pr e h e a t e r Co r p. (U.S.P. 1,820,199, 25.8.31. Appl., 10.8.25).—A continuous regenerator comprises a no. of stationary cells having vertical flow with horizontally rotating valves for the air and gases.

B. M. Ve n a b l e s.

Liquid heat-transferring com position. T. A.

Mo o r m a n n, Assr. to Sh a l e r Co. (U.S.P. 1,820,085, 25.8.31. Appl., 2.3.29).—A composition especially for use in vulcanisers comprises glycerin mixed with 10—

20% of C2H 4(0 H )2 containing about 1% H aO.

L. A. Co l e s.

Drying apparatus [for lum ber etc.]. J. B.

We l c h (U.S.P. 1,817,402, 4.8.31. Appl., 31.7.26).—

A progressive lumber kiln in which the temp, at the dry end is highest is provided with means to heat any inward leakage of air a t th at end. B. M. Ve n a b l e s.

Dehydrating apparatus. R. M. Wa s h b u r n, Assr.

to A. P. Hu n t (U.S.P. 1,817,048, 4.8.31. Appl., 31.12.28).—Desiccated material is drawn by a gas current through the hopper-shaped bottom of the desiccating chamber into a transverse tapered conduit, the slot leading from the hopper into the conduit being narrowest where the conduit is largest.

B. M. Ve n a b l e s.

Causing a reaction between an aqueous reagent and im purities in oil. A. E. Fl o w e r s, Assr. to

De La v a l Se p a r a t o r Co. ( U . S . P . 1,818,702, 11.8.31.

Appl., 9.6.27).—One fluid, preferably the oil, is circulated through an elongated casing closely surrounding a hollow cylinder of porous m aterial; the other liquid is supplied to the interior of the porous cylinder, which has no outlet except through the pores. B. M. Ve n a b l e s.

Liquid [feed-water] treating apparatus. H. Be r g- q u i s t, Assr. to El l i o t t Co. (U.S.P. 1,818,188, 11.8.31.

Appl., 15.6.27).—In an apparatus for degasifying feed- water, the condensers in at least two stages are within the same casing as is the evaporator. B . M. Ve n a b l e s.

Heat-insulation m aterial. H. W. Gr e i d e r, Assr.

to Ph i l i p Ca r e y Ma n u f g. C o . (U.S.P. 1,819,893, 18.8.31. Appl., 18.4.29).—The material contains, e.g., 55% of a 1 : 1 mixture of Mg(OH)2 and CaC03 (preferably pptd. simultaneously from basic Mg carbonate solution), 15% of asbestos fibre, and 30% of kieselguhr ; MgC03

may also be added. L. A. Coles.

Treatm ent of [heat- and sound-]insulating m aterials. 0. F. Mo t t w e i l e r a n d D . C. Dr i l l, Assrs.

to Ge n. In s u l a t i n g & Ma n u f g. Co. (U.S.P. 1,818,346, 11.8.31. Appl., 25.11.27).—Material such as slag wool is impregnated with, e.g., petroleum during the wool- forming stage of manufacture, the petroleum being pre­

viously dispersed in the steam or air blast.

B. M. Ve n a b l e s.

Fire extinguisher. R. W. Au s t i n (U.S.P. 1,815,963, 28.7.31. Appl., 29.4.27).—Solutions for foam genera­

tion on admixture contain (a) K2C03, KOH, and a foaming agent (e.g., liquorice, saponin), and (b) H3P 0 4.

L. A. Co l e s.

Non-inflam m able liquid [for use in fire extinguishers]. G. 0. Cu r m e, j u n., Assr. to Ca r b i d e

& Ca r b o n Ch e m i c a l s Co r p. (U.S.P. 1,817,893, 4.8.31.

Appl., 30.4.27).—The liquid comprises CC14 and C2H4C12.

L . A. Co l e s.

Ham m er m ill. J. Mu r s c h, Assr. to Bu f f a l o Ha m m e r Mi l l Co r p. (U.S.P. 1,818,570, 11.8.31. Appl., 8.11.29).—A disintegrator for sheet material which might stay out of the range of the hammers in a partly broken state, work round, and obstruct the outlet screen is provided with a breaker plate which has upstanding ridges intercalating with the rows of hammers, the edges of the ridges being tangential to a circle of smaller radius than the max. of the hammers. B. M. Ve n a b l e s.

Crusher. 0. C. Wi n t e r s (U.S.P. 1,819,583, 18.8.31.

A p p l . , 20.2.30).—B e t w e e n a p a i r o f o p p o s i t e l y i n c l i n e d f i x e d j a w s a A - s h a p e d h e a d i s o s c i l l a t e d b y m e a n s o f a n e c c e n t r i c a n d l i n k s . B. M. Ve n a b l e s.

Grinding m ill. P. Ki t t a y (U.S.P. 1,820,462, 25.8.31. Appl., 15.5.29. Austr., 18.5.28).—To the inlet side of the casing are attached grinding rings inter­

calating with others on the rotating disc, the outermost- one having a serrated face. B. M. Ve n a b l e s.

Grinding wheel, and method of producing it, for flour m ills, pulp m ills, etc. J. W. Yo u n g (B.P.

369,378,10.3.31).—Discs are built up from spirally wound ribbon or strand of textile material impregnated with abrasive and binding material. If single strands are used, one face of the disc may have abrasive of coarser texture than the other. B M . Ve n a b l e s.

Cleaning of coal and other interm ixed m ate­

rials. Wo o d a l l- Du c k h a m (1920), Lt d., ( Si r) A. McD.

Du c k h a m, and H . Ha l m s h a w (B.P. 369,284, 14.5.31).—

A first concentrate of, e.g., coal is obtained from the end of a dry jigging table assisted by currents of air ; the middling product from the side of the dry table is treated in a wet separator and the concentrate is added to the other coal. B. M. Ve n a b l e s.

Mixer. K. Ad a m s(U.S.P. 1,820,171, 25.8.31. Appl., 21.1.30).—A mixer for stiff concrete etc. comprises a fixed bowl with one set of stirrers scraping the wall and part of the bottom and another oppositely rotating set lifting the material in the centre and sending it outwards.

B. M. Ve n a b l e s.

Dispersion. F. Zw i l g m e y e r, Assr. to Na t. An i l i n e

& Ch e m. Co., In c. (U.S.P. 1,817,958, 11.8.31. Appl., 21.8.26).—The substance in the fluid state is mixed with an emulsifying agent and the dispersion medium and impelled by steam or other motive fluid through a sinuous passage, the steam preferably meeting the mixture through jets a t right-angles, as in a scent spray. The process is particularly applicable to the prep, of an emulsion of NHPh2, which; is liquefied before mixing, for the production of azo dyes. B. M. Ve n a b l e s.

Machine for separating liquids from solid bodies m ixed or suspended therein. R. E. Wa g n e r a n d J. D.

Ul l g r e n, A s s r s . t o Ak t i e b. Ka r l s t a d s Me k a n i s k a We r k s t a d ( U . S . P . 1,817,594, 4.8.31. A p p l . , 6.6.30.

S w e d ., 30.3.29).— T h e s o l i d m a t t e r , e.g., w o o d p u l p , is c o l l e c t e d o n w i r e b e l t s p a s s i n g o v e r v a c . r o l l e r s a n d is s q u e e z e d i n t h e n i p o f t h e r o l l e r s : t h e c a k e w h e n f r e e

a 2

B r itis h C h e m ic a l A b s tr a c ts —B .

4 8 0 Cl, I . — Ge n e r a l ; Pl a n t ; Ma c h i n e r y.

is attracted as a whole to one of the belts (rather than unevenly to both) by adjustment of plates behind the belt, permitting the vac. to be kept on at one side a moment longer than a t the other. B. M. Ve n a b l e s.

Filter. C. B . Foley, Assr. to S. F. B o w s e r & Co., Inc. (U.S.P. 1,820,533, 25.8.31. Appl., 18.7.29).—Filter discs are constructed of a pair of spirally -wound metallic ribbons w ith lune-shaped piercings, the pair being assembled so th a t the horns point in opposite directions.

B . M . Ve n a b l e s.

Filter-press leaf. R. L. Ho l c o m b and E. E. Ba r t e l s,

Assrs. to St a n d a r d Oi l Co. (U.S.P. 1,818,623, 11.8.31.

Appl., 13.4.28).—The filter medium is bolted to a solid frame which is welded to a hollow frame forming the outlet for filtrate. B . M. Ve n a b l e s.

Filtering-apparatus. J. W . Hu g h e s, Assr. to Bu d d Wh e e l Co. (U.S.P. 1,819,602, 18.8.31. Appl., 2.8.26).—

To the suction pipe of a centrifugal or other large-vol.

pump is attached a breeches piece each leg of which is provided with a strainer foot. The crutch is formed as a cylinder, from the middle of the length of which the single suction pipe leads to the pump. A piston recipro­

cating in the crutch acts also as a valve, cutting off each leg in turn from the pump and simultaneously causing a back-flow through th at leg and screen.

B . M . Ve n a b l e s.

Centrifugal separator. E. W. T n iE L E , Assr. to

St a n d a r d Oi l Co. ( U . S . P . 1,817,593, 4.8.31. Appl., 29.10.26).—A misty vapour after passing through a screen, which somewhat increases the size of the drops, enters tangentially into a circular chamber, the outlet of which is tapered and further increases the whirling prior to admission to another separating chamber.

B . M . Ve n a b l e s.

[Centrifugal] separators. P. B. Sh e e, Assr. to

Se a r s, Ro e b u c k & Co. (U.S.P. 1,817,464—5, 4.8.31.

Appl., 5.4.30).—In (a) a form of separable bowl and cover is described, and in (b) a bowl cover in two pieces with means to prevent leakage along the outer surface of the neck. B. M. Ve n a b l e s.

[Centrifugal] separating apparatus. T. and J. R . Ra y (U.S.P. 1,817,207, 4.8.31. Appl., 1.3,28).—

A centrifugal separator of the impervious-wall type has a smaller chamber a t the feed end in which a preliminary separation of the coarser solid m atter is effected and from which it is continuously removed, thus postponing the time when it is necessary to stop and clean the main chamber. B. M . Ve x a b i.e s.

[Laboratory] distilling apparatus. M. R.

Mi t c h e l l and R. W. Sk o o g, Assrs. to Ba l t i m o r e Ga s En g. Co r p. ( U . S . P . 1,819,190, 18.8.31. Appl., 15.9.27).—In a laboratory still, direct heat is applied to the H 20 in an annular open-feed launder before entering the still chamber. B . M . Ve n a b l e s.

Concentration of aqueous solutions of volatile substances [ e . g . , acetic acid]. F . E. Li c h t e n t h a e l e r

(U.S.P. 1,817,993, 11.8.31. Appl., 19.5.25).—The H„0 is removed by the hydration of an anhyd. salt, e.g., alum, and the volatile substance removed from the spongy mass of salt by a current of gas (inert to the volatile substance) at a temp, below the m.p. of the

hydrated salt, and recovered by condensation or other

means. B. M. Ve n a b l e s.

Evaporation and concentration of solutions.

C . B. Cl a r k, Assr. to Ge n. Ch e m. Co. (U.S.P. 1,817,349, 4.8.31. Appl., 5,2.27).—Solutions of salts, e.g., A12(S04)3, having their b.p. close to their f.p. and therefore tending to become viscous in spray evaporators having a dry atm., because the temp, of the solution is largely deter­

mined by the wet-bulb temp, of the atm., are sprayed into an atm. which is recirculated through a superheater and deliberately allowed to remain so moist th a t the wet-bulb temp, is above the setting point of the conc.

solution. Sufficient moisture to continue the use of the same atm. is condensed out, preferably in a heat exchanger which forms the heater of a vac. evaporator for the early Btages of the same liquid.

B. M. Ve n a b l e s.

Evaporation of liquids, drying of m aterials, or crystallisation of salts from their solutions.

E.M.S. In d u s t r i a l Pr o c e s s e s, Lt d., and R. A. St o k e s

(B.P. 369,359, 26.2.31).—The fluid is passed in succession through a no. of superposed troughs which are heated both by jackets and by internal drums, and are provided with scrapers which operate on both the drum and trough surfaces. B. M. Ve n a b l e s.

Preparation of durable, dry products from liquids, suspensions, em ulsions, and the like by evaporation. J. H. Ak k e r m a n (B.P. 369,136,8.8.31).—

Liquids, suspensions, etc. containing albumins, vitamins, enzymes, etc. are conc. below 37°, dried « O '5% H 20), and the powder is sterilised a t > 85° for 20 min.

E. H. Sh a r p l e s.

Air filters. A. W. S t e w a r t (B.P. 369,400, 21.3.31).

—The use of perforated metal strips or sheets in spiral

o t scroll form is claimed.

Filter apparatus [for air or other gases].

A . Jo r d a h l, A s s r . t o Am e r. Ai r Fi l t e r Co., In c. (U.S.P.

1,816,854—5, 4.8.31. A p p l . , [a] 6.5.26, [b] 12.6.26).—

I n (a) c e lls o f f i l t e r m e d i u m a r e c o n n e c t e d t o g e t h e r t o f o r m a c h a i n ; i n (b) t h e c e lls a r e d e t a c h a b l e f r o m f r a m e s w h i c h f o r m t h e c h a i n . B. M. Ve n a b l e s.

Separating and rem oving dust and ash particles from flue gases by w ashing. E. Ha b e r (B.P.

369,376, 9.3.31).—The flow of the gases is reversed above the surface of a pool of the washing liquid, close to which surface steam-jets are rotated, pointing upwardly and spraying the water. After the change of direction at the main pool the gases may be reversed again at a lower one. B. M. Ve n a b l e s.

Cleaning and coating of air filters. C. H. Gac.e n,

Assr. to Am e r. Ai r Fi l t e r Co., In c. (U.S.P. 1,816,836, 4.8.31. Appl., 21.4.27).—The filter is telescopic and is extended when in use. For cleaning purposes it is dropped into a tank of liquid and telescopes therein, so th at the tank need be only comparatively shallow.

When the filter is in use again the liquid may be regener­

ated by filtration or other treatment.

B. M. Ve n a b l e3.

Impregnation of [sm oke] filters [for respirators].

N. E. Og l e s b yand R. S. Br o w n, Assrs. to H. A. Ku h n

(U.S.P. 1,818,155, 11.8.31. Appl., 28.10.26).—The filter is impregnated by colloidal C produced, e.g., by the crack-

B r itis h C h e m ic a l A b s tr a c ts — B .

Cl. X I.— Fu e l ; Ga s ; Ta b ; Mi n e r a l Oi l s. 4 8 7

ing of oil vapour or gas, and deposited on the filter as soon as possible to prevent growth of the particles, the necessary period of cooling to prevent damage to the filter being kept a t the min. B. M. Ve n a b l e s.

Plant for treating gas. B. Rz e c z k o w s k i (U.S.P.

1,820,161, 25.8.31. Appl., 10.1.29. Poland, 23.1.28).—

Liquid sprays operated by compressed air are projected horizontally across a tower from slots which extend the full width of the tower and are staggered as regards height on opposite sides. B. M. Ve n a b l e s.

T esting instrum ents for m easuring the m echan­

ical properties of steel and other m aterials. L. H.

Ho u n s f i e l d (B.P. 369,432, 17.4.31).—In measuring the usual mechanical properties, the load is applied through a stiff spring, the deflection of which is measured by external optical means. C. A. Ki n g.

Friction m aterials. Soc. An o n. Fr a n? , d u Fe r o d o

(B.P. 369,506, 4.8.31. F r . , 7.8.30. Addn. to B.P.

264,471; B., 1928, 413).—Pb powder and fine Pb shot, or other metals in the form of turnings etc., are incorpor­

ated in the fibrous material (asbestos thread waste or wadding) before agglomeration. H. Ro y a l- Da w s o n.

Manufacture of asbestos friction elem ents [clutch rings]. L. Ki r s c h b r a u n, Assr. to Ra y b e s t o s-Ma n- h a t t a n, In c. (U.S.P. 1,810,714, 16.6.31. Appl., 31.10.28).—Unwoven felted asbestos rings are impreg­

nated a t 149—177° for about 2 hr. in a 4 :1 mixture of a Mexican crude petroleum (d 0-985) and gas oil and are then heated a t 93°, rising to 260° in 5 hr. The rings are baked a t 260° for 12 hr., reimpregnated, and baked for a further 12 hr. a t about 260°. The final product has a Brinell hardness of 15—25 and a tensile strength of 2000—3000 Ib./sq. in. D. J. No r m a n.

[Burner for] obtaining high temperatures in a rotary furnace, with a view to m elting ores or other m aterials. H. Ga r r e a u (B.P. 370,035, 30.12.30).

[Combined deflection and whirling type of com pressed-]air scrubbers and the like. Fa r r i n g- d o n Wo r k s& H. Po n t if f.x & So n s, Lt d., and J. Ch i g n e l l

( B . P . 369,524, 21.9.31).

Reheating furnaces. B rass [for condenser tubes],—See X. Detecting suspended m atter in fluids. Rem oving dust from ga ses.—See XI.

II.— FU EL; G A S ; T A R ; MINERAL OILS.

Properties of coal seam s. F. S . Si n n a t t (Gas J., 1932,198, 35—37).—A generalisation of the information given in the various published papers of the Physical and Chemical Survey of the National Coal Resources.

C. B . Ma r s o n.

Specific-gravity investigation of com m ercial coal sam ples. P . E. Ha l l (J. Chem. Met. Soc.

S. Africa, 1932, 32, 174—180).—Tabulated data are given which show th at the % of material which sinks in CC14 (d 1-6) affords a suitable measure of the amount of impurity present in Natal coals, and the % of ash in the heavy material indicates the type of impurity

(shale, sandstone, and pyrites). A. R. Po w e l l.

Tendency of coal to spontaneous com bustion.

I. D. J. W. Kr e u l e n (Chem. Weekblad, 1932, 29, 201—204).—The “ initial temp.” is defined as the

point of intersection of the temp, line of the coal and a line parallel to, but 6° above, the temp, of the jacket (cf. B., 1930, 847). This temp, has been determined for 5 different coals; it varies from about 145° for a coal containing volatile matter 41-6%, ash 4-2%, II20 14-1%, to about 200° for a coal containing volatile matter 14-7%, ash 6-0%, H |0 0-3%. The method provides a more satisfactory classification of coals than has been available hitherto. Tests made in an atm. of 0 2 are more accurate than those carried out in air, and indicate satisfactorily the behaviour of a coal in air.

H. F. Gi l l b e.

Standard method for determ ining the caking index of coal. R. Ka t t w i n k e l (Brennstoff-Chem., 1932, 13, 103—104; cf. B„ 1926, 905).—The apparatus and technique of a modified Meurice caking-index determination are described in detail. A mixture of 1 g. of coal with 17 g. of specially selected sand is carbonised a t 1000° ( ± 50°) in a P t crucible, and the crushing strength of the coke button is then determined.

The caking index is given b y : (crushing strength in

g,)/17. A. B. Ma n n i n g.

U tilisation of coals from southern Brazil. A.

Gi r o t t o (Ann. acad. brasil. sci., 1931, 3, 79—81).—

The solvent action of the acid liquor from marcasite- bearing coals is greater than th a t of corresponding H2S 04- f FeS04+ F e 2(S04)3 solutions.

Ch e m i c a l Ab s t r a c t s.

Low-temperature carbonisation [Salem i sy stem ].

P. Sa l e r n i(Gas J., 1932, 197, 454—455).—A mixture of finely-ground coal, semi-coke, and the heavy oil pro­

duced in the process is carbonised by heating a t 450°

in a revolving drum. The coke is discharged by gravity in the form of spheroidal blocks of high density and coherency. The oil produced is free from dust and has a low sp. gr. due to its second passage through the retort.

By blending non-caking coals with high-temp. pitch a satisfactory semi-coke is obtained. As there is no relative motion between the working parts of the retort, even if overheated, distortion will not take place.

R. N. B . D. Br u c e.

U se of dilute am m oniacal liquor for coke quench­

ing. C. B . Ma r s o n and H. V . A. Br i s c o e (Fuel, 1932, 11, 152—153).—Further experiments are described and the earlier conclusions ( B ., 1931, 790), th at liquor quenching has no effect on the quality of the coke, are

confirmed. C. B. Ma r s o n.

Oven for determination of ash in solid fuels.

H. Br u c k n e r and G. Se u f f e r t (Gas- u. Wasserfach, 1932,75, 276—277).—Four crucibles containing the fuels are supported on a porcelain plate heated at 850° by radiation from a series of electrically wound S i 0 2 rods.

A long porcelain tube placed over each crucible draws a current of hot air over the fuel and assists its com­

bustion. Coal, in distinction to coke and breeze, must be heated gently for the first 5 min. The overall time for a determination is 30—50 min., compared with 90—240 min. using the ordinary gas-muffle method. Consistent results, which agree with those given by other methods, are obtained. R. N. B . D. Br u c e.

U se of sm all coke in gasw orks. A. Ko l a r (Gas- u.

Wasserfach, 1932, 75, 255—262).—Coke breeze, which

B r itis h C h em ica l A b s tr a c ts —B . .

4 8 8 Cl. IX .— Fu e l ; Ga s ; Ta r ; Mi n e r a l Oi l s.

may amount to 10% of the coke produced, can be burned direct under boilers, gasified to producer gas, or used as a briquetting medium. The combustion temp, varies greatly with the moisture content and amount of excess air used, and has a large effect on clinker formation.

The heat generated in unit time per const, grate area is larger for breeze than for any other solid fuel. The design of boilers and producers for treating breeze is discussed and details (heat balances, efficiencies, etc.) are given for a no. of plants installed in gasworks for the especial utilisation of breeze. R. N. B . D. Br u c e.

Low-temperature cooling and drying of gas, with special reference to the Lenze process. F. St e d i n g

(Gas- u. Wasserfach, 1932, 75, 164—169 ; cf. B., 1932, 296).—Methods of dehydrating gas are reviewed. In the Lenze process the gas is cooled to 5° in summer (0° in winter) by washing with chilled aq. NH3 and H 20.

The low-temp. cooler may be placed either before or after the usual purifying train. In the first case C10H8, tar, and NH3 are removed, the advantages being absence of tar fog in the oxide boxes, production of a conc. NH3- liquor, partial removal of polymerisable substances, e.g., indene, and complete removal of C10H8, thus eliminat­

ing blockage of mains. In the second case, C30Hfi and H 20 are removed, thereby eliminating blockage due to ice and corrosion of mains, service pipes, etc. A descrip­

tion of a plant treating 1 -5 million cu. m. of gas per day is given, whereby the NH3, tar, and C10He contents are reduced to 2, 2, and 0-25 g. per 100 cu. m. The costs of the process, using absorption and compression cooling units, are given as 0-0145d. and 0-016d. per cu. m., respectively. R. N. B . D. Br u c e.

Improvement of gas by low-temperature cooling and catalysis. II. Re h m e r (Gas- u. Wasserfach, 1932, 75, 269—273).—Gas, after passing through the usual train of condensers, is treated a t 0° with dil. NH3- liquor, which is thereby conc. to 4%. I t is then washed with oil at —10° to —20° to remove last traces of C10H8 and C6H6, and most of the organic S and polymerisable compounds. At —10° only 0-15 cu. m. of oil is needed for treating 1000 cu. m. of gas. H2S is removed by any of the usual wet or dry processes. The cooling is supplied by an NH3 absorption-refrigeration plant, worked by the sensible heat of the flue gases. The gas is then saturated with II20 at 70° and passed through a series of catalyst vessels a t 300—380°; the CO is decomposed in two ways: C 0 + H 20 C02 + H2, and CO + 3II2 -> CII4 -f H 20. Ni, Fe, Co, Cu, Mn02, Cr20 3 alone or mixed with alkalis and alkaline-carths are active catalysts. Ni, which is the most efficient, also saturates any unsatu­

rated hydrocarbons present. A gas treated with Ni + 15% T h02 a t 300° changed in composition as follows : C02 5-2% (to 5-9), unsaturateds 2-1% (0*3), 0 2 0-4%

(0-2), CO 15-9% (4-6), H 2 48-3% (24-4), CH4"l8-4%

(26-9), and N2 9-7% (10-1). If water-gas is purified the high % of C02 present may be removed by pressure- washing ; the gas must always be dried before sending out to the consumer. The sp. gr. and calorific val. are decreased only slightly ; the vol. decreases about 30%.

The costs of the process are discussed, taking into account the advantages of elimination of blocking and corrosion troubles, and removal of toxic properties.

R. N. B. D. Br u c e.

Rendering gas non-toxic by bacterial m eans.

R. Li e s k e (Gas- u. Wasserfach, 1932, 75, 228—229).—

The author agrees with Bertelsmann (B., 1932, 296) and points out th at by raising the temp, and by other means the reaction velocity may be increased 15-fold. Bertels­

mann’s method of calculation is criticised. The contrac­

tion in vol. during the process should be included.

R. N. B . D. Br u c e.

Odorising of gas. W. v o n Pi o t r o w s k i and J.

Wi n k l e r (Gas- u. Wasserfach, 1932, 75, 262—263).—

The properties of an ideal substance for treating natural gas are discussed. EtSH is considered unsuitable owing to its high price, volatility, and poisonous properties.

Coal-tar fractions must be used in high concns. and lose their odour on passing through earth ; carbyl- amines are too expensive. Tar-oil fractions rich in unsaturateds (A) and in org. S compounds (B), hydro­

carbons containing aldehydes produced by oxidation (C), and oils formed by reaction of G with NH3 (D) have been examined. The wt. in g. of the following com­

pounds necessary to odorise 1 cu. m. of gas is : EtSH 0-15—0-20, coal-tar fraction 5—10, A 2—5, B 0-25, C 0-8—1-0, G + EtSH (1 :1 ) 0-2, and D 0-6—0-8.

R. N. B . D. Br u c e.

Combustion reactions in flam es. K . Bu n t e (Gas- u. Wasserfach, 1932, 75, 213—218).—Graphs are given for the change in velocity of combustion of mixtures of air and the following substances: CH4, C2H4, C2H 2, C3H8, C3H6, C5H 10, C6H12, C6H14, CS2, COMe2, E t20, and CgH6. In each case a max. occurs. The effect of added CO on these maxima is shown. The combustion of CO, H2, and hydrocarbons is discussed from a theor­

etical view-point. R. N. B . D. Br u c e.

Modified apparatus for d eterm in in g nitrogen in coal gas and allied gases. D. J. S. Ro b b (Chem. Eng.

Min. Rev., 1932, 24, 178).—The apparatus comprises a gas burette, a S i0 2 combustion tube packed with CuO, two absorption pipettes, a measuring pipette, and a C02 Kipp apparatus for flushing out the combustion tube.

100 c.c. of the gas are passed to and fro over the CuO, heated to redness by a burner, until combustion is com­

plete ; the C02 and any residual 0 2 are then absorbed in 40% aq. KOH and alkaline pyrogallol, respectively, and the residual N2 is measured. A. B. Ma n n i n g.

N itric oxide content of coke-oven gas. P.

Sc h u f t a n (Brennstoff-Chem., 1932, 13, 104—108; cf.

Pieters, B,, 1931, 956).—NO in coke-oven gas is deter­

mined by passing a mixture of 2 vols. of the gas (pre­

viously freed from NH3 and H 2S by washing with aq.

KOH) with 1 vol. of 0 2 through a reaction bottle in which the gases have a contact time of 15 min., and thence through a solution of ?n-C6H4(NII2)2 in dil. AcOH. The N 0 2 formed is thereby determined colorimetrically and the NO content of the original gas calc, therefrom, account being taken of tlie incomplete conversion of NO into N 0 2 when equilibrium is attained under the experi­

mental conditions. This method and the “ static ” method described by Tropsch and Kassler (B., 1931, 1033) both give satisfactory results for gases containing 10~4 to 5 x 10~5 vol.-% NO. A. B. Ma n n i n g.

Coke-oven gas for iron-sm elting furnaces. E.

Ma a s e(Feuerfest, 1932,8 , 33—37).—A discussion of the

B r itis h C h e m ic a l A b s tr a c ts —B .

Cl. I I . — F u e l ; G a s ; T a b ; M i n e r a l O i l s . 4 8 9

economics of various gases and gas mixtures for firing smelting and heat-treating furnaces in the steelworks.

Coke-oven gas can be used in admixture with blast­

furnace gas for heating steel furnaces provided th at the mixture is preheated a t above 1100° or is carburised with tar vapours, and th a t the moisture content of the blast-furnace gas is reduced to < 4%.

A. R. Po w e l l.

Distillation of coal tar. J. M. We i s s (Chem. &

Ind., 1932, 219—223, 246—250).—A review of the various stills in use for the distillation of tars, especially coke-oven tars, is given. The effect of vac., steam, and gas recirculation on the yields of oil and pitch from batch stills is discussed. The yield of oil is increased by the use of series batch and pipe stills. A recent type, described in detail, involves contacting the ta r with raw hot coke-oven gas, whereby the sensible heat of the gas is used, and volatilisation takes place a t a lower temp., thus giving max. oil yields.

R. N. B . D. Br u c e.

General constituents of Japanese petroleum.

II. Composition of fractions distilling above 200°

at atm ospheric pressure. R. Ko b a y a s h i (J. So c.

Chem. Ind., Japan, 1932, 3 5 , 107—111 b ; cf. B., 1931, 1034).—The residue from distillation at 200° has been fractionally distilled in vac. up to 230°. Details of the physical properties and constitution of the rectified fractions from 5 samples are detailed. The presence of Ci4H 28, C15H30, C16H32, and C17H34 is assumed.

E. Le w k o w i t s c h.

Handling of liquefied petroleum gases. T. W.

Le g a t s k i (Chem. Met. Eng., 1932, 39, 155—156).—

The thermal expansion of C4H 10 and other liquefied petroleum gases of b.-p. range —45° to 8° were determined by H 20 displacement and by measurement of pressure developed, the v.p. and sp. gr. for each sample being also measured. From these results the free space necessary when loading any liquefied petroleum gas in either tank cars or drums is calc., the possible rise of temp, being taken as up to 40° in the first case and to 55° in the second. C. Ir w i n.

Production, selection, and application of lubri­

cating oils. F. J. Sl e e (Papermaker, 1932, 83, Suppl., 184—186).—A brief review.

Determination of acidity of [lubricating etc.]

oils, using alkali-blue 6B as indicator. A. R.

Ma t t h i s (Chim. et Ind., 1932, 27, 503—512).—Alkali- blue 6B is especially suitable for titrations in an E tO II- C6H6 (2 : 1) medium. A filtered, fresh, 1—2% solution of the solid indicator in 94 or 96% EtOH (about one third is insol.) is preferable to the solution supplied commercially. The indicator should be used in the cold;

O’lA7-alcoholic K01I is suitable for titration, and it is better to do a blank than to attem pt to neutralise the solvent prior to titration. The end-points are clear and the liquid may be agitated by a stream of C02-free air where desirable. E. Le w k o w i t s c h.

Utilisation of acid sludge from lubricating oils.

Ny u r e n b e r g (Groznenski Neft., 1931, 1, No. 8—10, 116—118).—Acid is more easily recovered from the second (12—15% of acid) than the first (6—10% of acid) sludge by agitation (1-5 hr.) with 2 vols. of H aO at

93°, whereby the sulphonic acids are decomposed. The acid which separates contains 18—35% of free acid. The sludge is again treated with hot H20 . About 70% of the spent acid can thus be recovered. The residue is treated with fuel oil for use as fuel.

Ch e m i c a l Ab s t r a c t s.

Heat exchangers.—See I. Detection and separa­

tion of hydrocarbons.—See III. Rubber packings in gas w ashers.—See XIV.

Pa t e n t s.

Coke oven. C . H . Hu g h e s, Assr. to Se m e t-So l v a y En g. Co r p. (U.S.P. 1,818,713,11.8.31. Appl., 13.5.26).—

The walls between the heating flues and tlie coking chambers of a by-product coke oven are constructed of a material of relatively high thermal conductivity consisting of approx. 90% of S iC and 10% of a refractory bonding material, e.g., fireclay. The opposite walls of the flues are constructed of a heat-insulating material consisting substantially of Z r02. A. B. Ma n n i n g.

Production of coke and gas in horizontal chamber ovens. C. St i l l (B.P. 369,089, 11.6.31. Ger., 19.6.30.

Cf. B.P. 356,079 ; B., 1931,1036).—A travelling device is provided on the roof of the oven which permits a series of rods or tubes, suspended on winding cords, to be lowered into the charge of coal through suitable openings in the roof, and then raised again, in order to form vertical ducts in the charge and thereby facilitate the rapid with­

drawal of the gases and vapours therefrom during car­

bonisation. Each of the openings above the ducts so formed may be connected with a horizontal gas-collecting pipe in the oven roof, which, in turn, communicates with a gas and tar main. A. B. Ma n n i n g.

Manufacture of coke. T. B. Sm i t h, and Do r m a n, Lo n g& Co., Lt d. (B.P. 368,881,24.12.30).—Metallurgical coke is manufactured by carbonising an intimate mixture of pulverised coking coal rich in resinous binding con­

stituents with pulverised non-coking material, e.g., coke breeze or anthracite. The materials should be ground so th a t <£80% passes a 60-I.M.M. sieve. The proportion of non-coking material should be just sufficient to neutralise the excess of resinous binding constituents in the coking coal. The optimum propor­

tion is found by carbonising a series of mixtures under standard conditions, e.g5, by heating 25 g. a t 900° for 30 min. in a specially designed crucible, and determining the mixture giving the coke of max. crushing strength.

A . B. Ma n n i n g.

Heat treatment of coal and like carbonaceous m aterial. E b b w V a l e S t e e l , I r o n & C o a l Co., L t d . ,

and D . Thickins (B.P. 368,820, 9.12.30).— A smokeless fuel of high calorific val. and density is produced by carbonising a charge of coal within an externally-heated container provided w ith vents of comparatively small area such th a t during carbonisation considerable gas pressure is developed within the charge. The hydro­

carbon gases and vapours gradually passing outwards through the hotter portion of the charge are cracked, active C being deposited thereby in the cells of the coke.

The container m ay comprise two main portions, each of channel shape in cross-section and fitting together, and an end door. One or more charged containers are heated in a muffle furnace or oven. A. B. M a n n i n g .

B r itis h C h em ica l A b s tr a c ta —B .

4 9 0 C l . IX .— F u e l ; Ga s; Ta r; M i n e r a l , O i l s .

Distillation of carbonaceous m aterials. W. E.

Tr e n t, Assr. to Tr e n t Pr o c e s s Co r p. ( U . S . P . 1,818,912, 11.8.31. Appl., 20.1.26).—A chamber comprising a metal cylinder of substantial thickness surrounded by an insu­

lating jacket is heated by the combustion therein of pul­

verised coal or oil. A charge of the carbonaceous material, e.g., coal, oil, or plastic coal-oil mixture, is then intro­

duced and is carbonised or cracked by the heat stored in the walls of the chamber. The latter is preferably supported on rollers so that it can be rotated during the treatment. The volatile products are withdrawn through a suitable outlet and collected. When carbonisation is complete the residue is discharged and the cycle of opera­

tions repeated. A. B. Ma n n i n g.

Destructive-distillation apparatus. E. L. Day

(U.S.P. 1,820,600, 25.8.31. Appl., 17.12.28).—From the heated chamber the gases pass through fractionating units : (a) in the base of a tower, (6) to and fro in a horizontal extension therefrom, and (c) up the remainder of the tower, all zones having suitable filling.

B. M. Ve n a b l e s.

Distillation of pitch into coke. C . V. McIn t i r e,

Assr. to Co n s o l i d a t io n Co a l Pr o d u c t s Co. (U.S.P.

1.817.926.11.8.31. Appl., 3.2.28. Cf. U.S.P. 1,479,827;

B., 1924,209).—The pitch is passed continuously through a horizontal retort which is heated from below. The bottom of the retort is of metal and is corrugated in such a manner as to form deep transverse grooves.

The upper part of the retort and the end walls are of refractory material. The pitch is agitated during distil­

lation by means of rotating paddles attached to a hori­

zontal shaft. The volatile products are withdrawn through a suitable outlet and the coke is discharged in the form of carbonised pellets. A. B. Ma n n i n g.

Manufacture of ( a ) active carbon, (b ) activated charcoal. H. B. Hass, Assr. to G a s o l i n e R e c o v e r y C o ri* (U.S.P. 1,819,165—6, 18.8.31. Appl., [ a ] 28.5.27,

[ b ] 17.9.28).—( a ) Carbonaceous materials are impreg­

nated with H3P 0 4, calcined in the absence of 0 2, and then partly oxidised with, e.g., C02 or H 20 at > 700°.

(b) Charcoal is heated at 700—1100° in an inclined rotary kiln in the presence of C02, steam, etc., which gases are introduced through holes in a stationary tube running down the axis of the kiln. The spent activating gases are partly burned by a controlled current of 0 2 and used again. The heat of combustion is used to maintain the temp, of the furnace.

R. N. B. D. Bruce. [Production of hard granular] activated carbon.

P. Zu r c h e r, Assr. to Co n t i n e n t a l Oi l Co. (U.S.P.

1,819,314, 18.8.31. Appl., 13.8.28).—Petroleum coke granules mixed with heavy hydrocarbons are treated with vapours containing S compounds a t 450°, and then heated at 650° with steam until all traces of S are removed. R. N. B . D. Br u c e,

Manufacture of carbon black. A. W. Fr a n c i s,

Assr, t o Ma g n o l i a Pe t r o i j s u m C o . ( U . S . P . 1 ,8 2 0 ,6 5 7 ,

25.8.31. Appl., 4.5.27).—Gaseous hydrocarbons and air a t a pressure 10 lb., preferably 300 lb., per sq. in.

are burned with a luminous flame, which impinges on a disc rotating in an enclosed vessel. The C black formed (8%) is scraped off the disc and withdrawn

through two gate valves. The exhaust gases may be used in a gas engine or waste-heat boiler.

R . N . B . D . Br u c e.

Dispersion of carbon. W . F. Tu l e y, Assr. to

Na u g a t u c k Chem. Co. (U.S.P. 1,818,770, 11.8.31.

Appl., 9.11.29).—The finely-divided C is heated with a 1—10% solution of an alkali sulphite in a polar liquid medium, e.g., I I 20 or EtOH. If the C is then separated by filtration, and is washed and dried, it will again disperse immediately when added to H 20, EtOH, etc.

A. B . Ma n n i n g.

Catalytic com bustion [in internal-com bustion engines] by m eans of refractories. G . H. Wy c k o f f,

Assr. to Do h e r t y Res. Co. (U.S.P. 1,820,878, 25,8.31.

Appl., 22.9.26. Renewed 3.1.31).—The combustion space is lined with native zircon containing traces of a radioactive substance. R. N. B . D . Br u c e.

Removal of carbon deposits [from internal- com bustion engines]. W . G . Lo v e l l and T. A.

Bo y d, Assrs. to Ge n. Mo t o r s Re s. Co r p. (U.S.P.

1,820,395, 25.8.31. Appl., 28.8.29).—The deposit is loosened by treating a t > 65° with an aromatic alcohol, e.g., CH2Ph-OH, furfuryl alcohol, or terpincol, alone or mixed with CfiH 0 and EtOH, and removed by blowing out through the exhaust. R . N. B . D . Br u c e.

Water-gas producers. Po w e r- Ga s Co r p., Lt d.,

N. E. Ra m b u s h, and J. 0. De a n ( B . P . 369,054,5.5.31).—

The blower of the plant is driven by a steam turbine, the exhaust steam from which is stored in a jacket boiler surrounding the generator. This steam, together with th at from the normal evaporation in the jacket boiler, is utilised during the “ make ” periods in the generator, whereby steam at a higher pressure than formerly is provided at the commencement of the gas-making period, the pressure then gradually falling off as the temp, of the fuel bed falls. High-pressure steam for driving the turbine may be generated in a waste-heat

boiler. A. B . Ma n n i n g.

Gas-manufacturing process and apparatus.

F. W . Sperr, j u n., Assr. to Koppers Co. (U.S.P.

1,817,777, 4.8.31. Appl., 5.8.26).—Coal gas is purified from HoS and HCN by means of an alkaline absorbent solution, which is reactivated by aeration, in known manner. The fouled air from the reactivation process is then utilised as the blast air of a water-gas generator, in the fuel bed of which the H 2S and HCN are converted into S 0 2, H 20, C02, and N2. The difficulty of co­

ordinating the supply of air from the reactivation process with the interm ittent demand of the generator is overcome by (a) operating several water-gas sets simultaneously, whereby the fluctuations in the demand are to some extent smoothed out, and providing an automatic regulator controlling the blower to the leactivating p la n t; (6) providing a gas-holder for temporarily accommodating any excess supply of fouled a i r ; or (c) providing a sump for the accumulation of fouled solution which is automatically supplied to the revivifier a t a rate proportional to the fluctuating

current of air passing therethrough. A. B . Ma n n i n g.

Production of gaseous m ixtures by treating carbonaceous m aterials. A. H. Ma l l e r y, Assr. to

Ma l l e r y Pr o c e s s Co r p. (U.S.P. 1,818,901, 11.8.31.