BRITISH CHEMICAL ABSTRACTS
B.—A P P L IE D C H E M IS T R Y
M A R . 14 a n d 2 1 , 1930.*
I.—GENERAL; PLANT; MACHINERY.
Heat transfer from a gas stream to a bed of broken so lid s. C. C. Fu r n a s (Ind. Eng. Chem., 1930, 22, 26—31).—Tlie transfer of Heat from air (of reduced oxygen content to minimise oxidation) to a bed of iron balls of varying sizes and covered with, a thin layer of rust was studied. Shielded thermocouples gave the temperature of either solid or gas as required.
The balls used were from 1-85 to 4-86 cm. in diam., air flow was from 0-01 to 0-053 litre/sec./cm.2, voids 39-5—50-6%, and temperatures up to 700°. I t was found that the coefficient of heat transfer from gas to solid varies with the 0-75 power of the gas velocity with constant temperature. With constant flow it is directly proportional to the temperature. Owing to the small size of the apparatus it w'as not possible to vary the particle size and the percentage of voids separately, but from certain assumptions it was con
cluded th a t with constant voids the coefficient per cm.2 of surface was independent of the particle size.
The conclusions are summarised in equations.
C. Ir w i n.
Efficiency of drying b y hot air relative to the m axim um perm issib le tem perature of the material.
0 . Ya jd a (Chem. Fabr., 1 9 3 0 , 2 5 — 2 7 ).—Graphs are given showing the relationships for a continuous hot-air dryer between (1) thermal efficiency and exit tem
perature, (2) total energy efficiency, including that required to move the air, and exit temperature. The total energy requirement falls with increase of tem
perature, but the permissible maximum temperature is limited by the nature of the material to be dried.
The relation between these two temperatures depends m\ whether the dryer works on the countercurrent principle or not. In the case of hygroscopic materials the degree of saturation of air which will effect drying is reduced in proportion with the reduction of vapour pressure by the material in solution. W ith the air and material moving in the same direction, the exit-air temperature is the maximum temperature of the material.
In a countercurrent dryer, safety under working con
ditions demands th a t the inlet-air temperature shall not exceed this maximum, but the reduction in possible saturation by hygroscopicity does not apply. I t is shown th a t for low maximum temperatures the counter- current dryer is the more economical, but for higher ones it is less so. The more hygroscopic the material, the greater is the advantage of the countercurrent
method. C. Ir w i n.
B oiler reactions at h igh tem peratures. W. L.
Denman and E. Bartow (Ind. Eng. Chem., 1930, 22, 36 39).—Corrosion tests were carried out in a laboratory
boiler operating a t a maximum pressure of 16 kg./cm.2, using charcoal-iron plates. These were cleaned from oxide by using them as cathodes in an. electrolytic cell. The tests were for 24-hr. periods, and in less than th at time the dissolved oxygen was exhausted and corrosion had ceased. The amount of corrosion was found to be directly proportional to the dissolved oxygen con
tent. Tests were also run with the addition of pyrogallol, oak extract, and sulphur dioxide. All reduced corrosion, oak extract in alkaline solution being found the most effective. Amongst inhibitors sodium arsenite was found to reduce corrosion, potassium dichromate was difficult to use effectively in the presence of halogens, the film being broken down with local corrosion, and if insufficient potassium dichromate was used corrosion was in any case increased. Some corrosion tests were also run with circulated water of varying hardness etc. The concentration of boiler water can be conveniently determined by the chloride content compared with th a t of the feed water. C. Ir w i n.
Internal corrosion of hot-water sy stem s by oxygen and carbon dioxide, and exterior injury to boilers by unsuitable fuel. G. Offb (Gas- u.
Wasserfach, 1930, 73, 73—76).—Oxygen and carbon dioxide in the presence of moisture at 70—80° produce visible corrosion on sheet iron in 12 hrs. and on zinc in 24 hrs. Efficient de-aerators are therefore necessary in hot-water plants employing these metals. The correct design of the boiler and arrangement of its connexions with a view to good circulation and elimination of gases is important. Other cases are recorded where failures of small boilers and water heaters were due to sulphur in the fuel (in one case wood waste, in another coke). Iron sulphide and free sulphur were found in the corrosion product, the air supply having been at times deficient. Such corrosion is much more severe than th a t produced by the equivalent of sulphur dioxide. I t is desirable to use good oven coke or gas coke burnt without the employ
ment of steam. C. Ir w i n.
[Boiler-]water softening. J. Go r d o n (G a s World, 1930, 92, Coking Sect., 10—14).—Figures for hardness of the feed water and boiler water in an installation in which water softened by addition of sodium hydroxide only was evaporated showed th a t considerable softening occurred within the boiler itself. W ith feed water at 12° average hardness, the average hardness and average alkalinity (grains/gal.) of the boiler water were 4° and 20-6, respectively. I t is concluded th a t the water after softening contains sodium bicarbonate, which forms sodium carbonate in the boiler, this then reacting with
calcium sulphate. S. I. Le v y.
* T he rem ain d er of th is s e t of A b s tra cts w ill a p p e a r in n e x t week’s issue.
221
B r itis h C h e m ic a l A b s t r a c t s — B .
222 Cl. I . — Gé n é r a i. ; Pla n t ; .Ma c h in e r y.
R. Fischer’s fall viscosim eter. H. L. Ma t t h i j s e n
(Chem. Weekblad, 1930, 27, 20—23).—The apparatus is more suitable than the Engler viscosimeter for deter
minations with very viscous fluids at 20°. The results obtained with various tars, varnishes, and paints are
tabulated. S. I. Levy.
The Ostwald colour system . F. Scholefield
(,T. Soo. Dyers & Col., 1930, 46, 5—7),—The method of construction of the Ostwald “ isochromatic triangle ” is described. Each triangle contains the “ bright clear range,” the “ dark clear range,” and every possible flat colour derivable from the particular full colour. The isochromatic triangles may be combined to form a
“ colour body ” in the form of a double cone, of which the periphery passes through all the full spectral colours and of which the axis represents the “ unhued ” range, with white at one end and black at the other. Colours harmonising with th a t represented by a particular point within the colour body are found on three straight lines and also on a circle passing through that point.
N. Ch a p p e l l.
Steam and power in cellulose works. Ma l m.—
See V.
Pa t e n t s.
Furnaces burning pulverulent fuels. A. W.
Be n n i s ( B .P . 323,219, 25.7.28).—The combustion cham
ber diverges from a grid at the bottom to the boiler at the top, primary air and fuel being admitted in a down
wardly inclined direction from the upper part. Part of the secondary air is supplied to the interiors of the hollow bars composing the grid, is thus preheated, and enters the furnace with a constant upward velocity.
The grid consists of a pair of squirrel-cage rollers or other moving device to discharge ash into a water-cooled conveyer. Another part of the secondary air may be preheated in the furnace walls. B . M. Ve n a b l e s.
Furnace fronts. [Burners for liquid and pul
verised fuels.] (a) W . A. Wh i t e ; (b) W . A. Wh i t e,
and Wh i t e Pa t e n t On, Bu r n in g Co., Lt d. (B.P. [a]
323,578,17.10.28, and [b] 323,661, 22.1.29).—Controllable devices are described which admit secondary air around burners for liquid or pulverised solid fuel, and afford provision for rapid change over of the fuel. In (a)
reference is mainly to the arrangement of four frusta of cones forming the walls of passages for secondary air, and in (b) to mounting of the Venturi tube, and to flame and air controls upon a double-hinged door, whilst the fuel supply valve is attached to a fixed part.
B. M. Ve n a b l e s.
[Tunnel] kiln. H . M. Ro b e r t s o n ( U .S .P . 1 ,7 3 7 ,5 4 0 , 2 6 .1 1 .2 9 . Appl., 2 5 .2 .2 8 ).—In a tunnel kiln combustion takes place in side chambers which are constructed close to the trucks of material a t the hottest zone. The products of combustion are led through conduits in the side walls of the preheating zone, and transverse air- circulation is maintained over these conduits and the goods. Air is drawn through the side walls of the cooling zones and is used for combustion.
B . M. Ve n a b l e s.
Retorts, kilns, dryers, heat interchangers, etc.
C. II. La n d e rand T. F. Hu r l e y(B.P. 323,715, 6.7.28).—
Apparatus specially suitable for the transmission of heat
into coal for the purpose of low-temperature distillation comprises a vertical retort of which some or all of the walls are composed entirely of tubes through which heating medium is passed from an inlet header a t one end to an outlet header a t the other : the material travels longitudinally. The walls may be inclined to allow for expansion (or contraction) of the material during treatment, and gases may be permitted to leave (or enter) between the tubes anywhere or only at predeter
mined points. The walls (if any) not composed of tubes may be constructed of castings or brickwork.
B . M. Ve n a b l e s.
Heat exchanger. E. Ha b e r ( U .S .P . 1,737,189, 26.11.29. Ger., 31.10.23. Appl., 11.11.24).—Regulating devices are described for the flow of the fluids through a recuperator constructed of steel plates.
B . M. Ve n a b l e s.
Heat exchanger. R. E. Wil s o n, Assr. to St a n d a r d Oi l C o. ( U .S .P . 1,737,347, 26.11.29. Appl., 22.1.27).—
A heat exchanger consisting entirely of straight tubes th a t can be easily opened and cleaned is constructed of a solid block of metal in which the tubes are drilled or cast. They are connected by detachable headers so th a t alternate ones carry the different fluids and so th a t the flow is, as far as possible, countercurrent.
B . M. Ve n a b l e s.
H eat-exchange device. G. Fl in t e r m a n n (U.S.P.
1,736,906, 26.11.29. Appl., 26.7.27).—A heat exchanger is built up from a number of plates stamped with cup
like projections tapering slightly so th a t when the cups are nested the plates are spaced apart. The bottom of every cup is perforated with a large central hole and a ring of smaller ones. Through the central holes a tube is threaded tightly, or it may be made from a number of nesting sections. More than two fluids may pass through the apparatus. B . M. Ve n a b l e s.
Prevention of scale deposits in boilers. A.
He i n r i c h ( B .P . 306,145, 14.2.29. Ger., 1 7 .2 .2 8 ).—A continual equalisation is maintained, through the boiler wall, of the electrical P.D . between the earth and the atmosphere. To this end the boiler is earthed a t one or more points and connected at one or more points either to several metallic points projecting into the air, or to an antenna preferably arranged parallel to any existing power wires in the neighbourhood.
B. M. Ve n a b l e s.
Dehydrator. J. M. Yo u n g e r (U.S.P, 1,737,068, 26.11.29. Appl., 3.12.27).—The material, e.g., vegetables, is stacked on trays and conveyed on trucks longitudin
ally through the dryer. I t is first subjected to a sweating process in steam-laden air, and then passes through a number of separate drying compartments in each of which a transverse, continuous, and reversible circula
tion of nearly saturated heated air is maintained by means of fans and louvres at the sides. There is a minor addition of fresh air from conduits beneath the
floor. B . M. Ve n a b l e s.
Dehydrator. F . C. Ch a p m a n, Assr. to Ch a p m a n De h y d r a t e r Co. ( U .S .P . 1,737,533, 26.11.29. Appl., 2.7.28).—The apparatus, specially suitable for materials, such as cotton, through which the drying air has to be forced rather than passed over, comprises a tunnel with
B r itis h C h e m ic a l A b s t r a c t s — B .
Cl. I .— G e n e r a l ; P l a n t ; M a c h i n e r y . 223
side inlet for air (from a fan) near the middle of its length.
The material is contained in two longitudinal rows of perforated baskets on trucks and makes substantially air-tight connexion with the floor and roof, but the rows are spaced apart from each other and from the side walls.
The trucks are progressed interm ittently and are caused to skip across the transverse air inlet. Bulkheads are provided a t the leading ends of the central passage and at the trailing ends of the side passages, so th a t in the first half of the dryer the (low of air is in through the central passage, across the containers, and out through the side passages, whereas in the second half the flow is vice versa and consequently in the opposite longitu
dinal direction. Both streams of exhaust air are mixed with fresh, heated air and taken back to the fan.
B. M. Ve n a b l e s.
D ryer. N. Pa n z i r e v ( U .S .P . 1,736,980, 26.11.29.
AppL, 5.12.28. Ger., 21.3.28).—A number of horizontal conveyers are arranged over each other in a casing, and both runs are operative so th a t the material takes a downward zig-zag course. On every storey there are two conveyers with spaces both at the centre and sides.
The drying gases are adm itted through a longitudinal passage a t the bottom, pass up the central spaces, divide under a twin-arched roof, and pass down the sides to a pair of longitudinal outlets a t the bottom.
B. M. Ve n a b l e s.
Attrition m ill. E. M. Br e n n a n and A. P. Da n i e l,
Asms, to Ba u e r Br o s. Co. (U.S.P. 1,737,183, 26.11.29.
Appl., 8.3.28).—-A disc-grinder or similar type of mill is finely adjusted by means of a differential screw.
B. M . Ve n a b l e s.
Shaft packings for grinding m ills. Ha r t s t o f f- Me t a l lA.-G. ( Ha m e t a g), andE . Kr a m e r(B.P. 323,632, 24.12.28).—A twin bearing for a grinding mill of the dry, high-speed, or other type is arranged in a bearing block th a t makes an oil- and gas-tight joint with the casing of the mill and forms three chambers, viz., between the outer bearing and the driving means, between the two bearings, and between the inner bearing and the casing of the mill : a large sump chamber is also incorporated. The middle chamber is maintained full of oil by a pump, and oil throwers are situated in the other two, th a t in the inner one forming an oil screen by centrifugal force, in-which any dust escaping from the mill is entrained and run to the sump where it settles and whence the oil is pumped for re-use.
B. M. Ve n a b l e s.
D isintegrator or pulveriser and separator for solid products. At e l i e r s Ré u n i s, and E. Hi p p e r t
(B.P. 323,472, 29.9.28).—The powdered material is carried away from a disintegrator in a primary air current produced with or without the aid of a fan, and is caused to enter in the form of thin sheets a secondary air current, whence the too-coarse material drops out and is returned to the disintegrator. [Stat.. ref.]
B. M. Ve n a b l e s.
M ixing or separating apparatus. AnIm o s t a t,
L td ., and L. M. Hi r c h b e r g (B.P. 323.544, 5.10.28).—
Various forms of apparatus are described for mixing or scrubbing gases, for mixing solids while suspended in gases, etc. They consist of a straight or T conduit with distributing devices as described in B.P. 283,258, which
cause alternate expansions and contractions of the gas
streams. B. M. Ve n a b l e s.
Separating apparatus for [wet] treatment of ores, coals, etc. L. Ho y o is (B.P. 303,810, 9.1.29. Belg., 9.1.28).—The apparatus is of the upward-current type ; precautions are taken to make the current uniform over the whole section, and the downflowing feed enters in an annular manner. B. M. Ve n a b l e s.
Centrifugal separators. Ak t i e b. Se p a r a t o r (B.P.
299,422, 16.10.28. Swed., 26.10.27).—A bowl-type separator with discs is provided with three discharges, viz., two at the top for the lighter and heavier liquids, and a third downwards and inwards from a point near the bottom of the wall of the bowl for discharge of solids with the necessary quantity of liquid. The wall of the bowl may be conical to assist the travel of solids down
wards, and the outlets are preferably in the form of easily changeable jets. [Stat. ref.] B. M .^Ve n a b l e s.
Safety device for centrifugal m achines. H. J. M. C.
Kr a n t z (U.S.P. 1,736,975, 26.11.29. Appl., 25.10.26).—
A device is described for preventing the cover of a centrifuge from being opened unless the brake is on and the rotor at rest or nearly so. The motor switch, brake, and lock are operated by one lever. B. M. Ve n a b l e s.
Centrifugal m achine. A . U . Ay r e s, Assr. to
Sh a r p l e s Sp e c i a l t y Co. ( U .S .P . 1,737,137, 26.11.29.
Appl., 15.2.28).—A combined drag bearing and inlet is described for a super-centrifuge. B. M. Ve n a b l e s.
Filtering apparatus. J. B. Ve r n a y (B.P. 314,431, 21.6.29. Fr. 27.6.28. Addn. to B.P. 297,394; B., 1929, 459).—The double-storey apparatus described in the prior patent is provided with a vessel for repulping between the stages of filtration. B. M. Ve n a b l e s.
Fractional-distillation apparatus. R . B. Ch i l l a s, j u n., Assr. to At l a n t i c Re f i n i n g C o. (U.S.P.
1,736,845, 26.11.29. Appl., 25.2.26).—Bubbling-caps with downflow pipes are made interchangeable with plain caps so th a t the downflow of liquor may be dis
tributed as desired; they may be suitable for either round or long, narrow apertures in the plates, and the central down-pipe extends right through the top and has a radial or transverse passage to admit the liquor from a suitable depth on the tray. B. M. Ve n a b l e s.
Concentration of liquids at ver y low tem peratures.
P . C. Le m a l e (Addn. 32,681, 9.6.26, to F . P . 609,295 ; B., 1927, 241).—-The two stages of the vacuum are pro
duced by means of a water ejector which is coupled directly with the inside of the evaporator and, through a tubular apparatus provided with a throttle valve, with a heater for the evaporator. A . R . Po w e l l,
C rystallising vessel. Ma s c h in e n b a u-An s t a l t Hu m b o l d t ( G .P . 457,731, 15.12.25).—The vessel is provided with an internal cooling coil below which is a compressed- air pipe having a*number of air outlets closed by rubber lip valves so th a t air can be blown through the liquid to assist cooling and crystallisation. A. R . Po w e l l.
Apparatus for aerating and blending liquids.
J. W. Ba t t e r s b y (B.P. 323,242, 28.6.28).—The larger quantity of liquid (e.g., tap water) is caused to flow through a jet within a conduit, beyond the jet are holes
B r itis h C h e m ic a l A b s t r a c t s —B .
2 2 4 C l . I.—G e n k r a l ; P l a n t ; M a c h i n e r y .
for admission of air which is drawn in automatically and is well diffused, and further on still the smaller quantity of liquid [e.g., flavouring) is admitted at a controlled rate. B. M. Ve n a b l e s.
Feeding of liquids under predetermined con
ditions of speed and/or pressure. C. H. La n d e r
and T. F. Hu r l e y (B.P. 323,481, 2S.9.2S).—An appara
tus for delivering definite quantities of a liquid such as fuel oil at a definite rate by means of displacement by a heavier liquid such as mercury, which is supplied through a fine jet under a constant head, comprises three bulbs arranged in a closed circuit with capillary tubes on both sides of at least one of the bulbs, which is calibrated. Besides the closed circuit for lighter fluid there are an inlet jet for the heavier liquid in the highest bulb of all, an outlet for lighter liquid from the middle bulb, and connexions (w'ith stopcocks) for filling and refilling. If the apparatus is inverted a lighter liquid may be used as the displacer. B. M. Ve n a b l e s.
Method and apparatus for m aking em ulsions and m ixtures, applicable also for other purposes.
V. G. Wa l s iiand V . A. Co l l in s (B.P. 323,534, 4.10.28).
—A mixture which is to be converted into an emulsion, or into a substance of which the viscosity or surface tension is to be changed, is subjected in a closed vessel to a number of impulses from a piston, the main purpose of which is to produce pressure oscillations ; at the ends of its strokes, however, it serves also as a pump to draw' in fresh material and to force out emulsion through a small aperture. The motion of the piston may be suddenly accelerated when near the end of its in-stroke. Other applications indicated are : altering the viscosity of glucose, lowering the surface tension of castor oil, disintegrating molecular aggregates of tans, milk, etc. B. M. Ve n a b l e s.
Mechanical production of froth. E. Sc h r o d e r
and J. A. S. Va n De u r s (B.P. 306,550, 21.2.29).—
A gas and a froth-forming liquid are driven together, under a pressure at least 0-5 atm. above atmospheric, against stationary wires or rotary whipping apparatus.
In one form of apparatus the mixture is passed through a vessel containing a number of transverse baffles which are perforated alternately near the centre and near the circumference, and between which beaters rotate. Means may also be provided to hinder the rota
tion of the whole of the mixture. B. M. Ve n a b l e s.
Liquid and gas contact apparatus. Ba r t l e t t Ha y w a r d Co., Assees. of F. H. Wa g n e r (B.P. 307,453, 21.11.28. U.S., 8.3.28).—A tower is provided with perforated trays and the gas is forced up the tower with sufficient force substantially to prevent flow of liquid through the perforations ; downflow of the liquid is effected by siphons which maintain a predetermined level on the trays and deliver the liquid on to a series of discs rotated at centrifugal speed in, or just below, apertures which are left in the centres of the trays.
Additional fixed and rotating beaters and fixed wire screens may be provided above the trays and gutters around their edges. B . M. Ve n a b l e s.
Apparatus for using air or gases as a conveying m edium . Br i t. “ Re m a ” Ma n u f. Co. Lt d., P . H o w - d e n, a n d L . Ka h l e r ( B .P . 323,061, 8.10.28).—T h e c o n
duits are divided by longitudinal partitions into a number of separate conduits each provided with a valve at the inlet. When the load is reduced, valves are closed in sufficient number to maintain the velocity in the conduits remaining in use. B . M . V e n a b l e s .
Gas-purification apparatus. N .V . Ma c h i n e r i e e n e n Ap p a r a t e n Fa b r. ( F .P . 633,268, 26.1.28. Ger., 23.4.26).—To remove suspended solids or liquids from gases, the mixture is passed through a series of chambers provided with staggered channels the arms of which are at an angle of 50—70° to one another and their distance apart is half their length. A . R . Po w e l l.
Rem oval of dust from gases w ith m ovin g filters.
De u t s. Lu f t f i l t e r-Ba u g e s. m.b. H , Assees. of A.
Sc h r e m p p ( G .P . 457,430, 27.7.24).—The gas is passed through a series of continuously or interm ittently moving filters separated by stationary w'alls and pro
vided with a central opening in the axis of the apparatus for renewing the filtering medium. A. R . Po w e l l.
Separation of organic gases and vapours [from air]. I. G. Fa r b e n in d. A.-G., Assees. of A. En g e l h a r d t
(G.P. 455,175, 11.1.21. Addn. to G.P. 310,092; B .,
1921, 204 a).—The constituents absorbed by activated carbon from the gas mixture are removed from the carbon by superheated steam or the superheated vapour of organic solvents and the carbon is then dried and cooled by a current of flue gas. A. R . Po w e l l.
Gas washer w ith rotating centrifugal tubes.
W. Fe l d & Co. G.m.b.H. (G.P. 457,56S, 12.3.27).—
The apparatus comprises a closed, vertical, cylindrical vessel containing a number of flat bowls one above the other, into each of which dip a series of funnel-shaped concentric tubes carried by a central rotating axle so th a t the liquid is forced up the tubes by centrifugal force and is sprayed into the uext higher bowl in the form of a fine mist. The shape or position of the individual funnels is so arranged th a t the same volume of liquid passes up the annular space between every pair to ensure an even distribution of liquid throughout the chamber and consequent efficient washing of the
g as- A . R . Po w e l l.
Production of a dry m ixture of ch em icals su it
able for preparing fire foam . K . Sc h m i d t, Assr. to
Py r e n e-Mi n im a x Co r p. (U.S.P. 1,739,094, 10.12.29.
Appl., 18.4.27. Ger., 1.9.26).—Aluminium sulphate, sodium bicarbonate, saponin, and sodium carbonate are dried separately at 60°, then mixed, and ground pumice is added. H. Ro y a l- Da w s o n.
Machine for testing strength and ela sticity of m aterial. Go o d y e a r Ti r e & Ru b b e r Co., Assees. of M. L . Ko c h h e i s e r and S . A. St e e r e (B.P. 306,555, 22.2.29. U .S ., 23.2.28).—A pair of cords, standard and sample, are stretched equally and simultaneously by means of a screw-operated stretcher. B. M. Ve n a b l e s.
Boiler for evaporation or heating of liquids.
A. L. Hitchcock-Spencer (U.S.P. 1,743,918, 14.1.30.
Appl., 27.3.29. U.K., 23.3.28).—See B.P. 319,380;
B., 1929, 963.
E dge filtration. H. S. Hele-Shaw and J. A.
Pickard (U.S.P. 1,744,510, 21.1.30. Appl., 20.11.25.
U.K., 17.12.24).—See B.P. 249,202; B., 1926, 423.
B r i t is h C h e m ic a l A b s t r a c t s — B .
Cl. I L — F u e l ; G a s ; T a i i ; M i o t s b a l O i l s . 2 2 5
[Baffles for flues of boiler] furnaces. Y. Haya- SHIDA (B.P. 323,562, 9.10.28).
Com bustion product power plant. A .-G . Br o w n, Bo v e r i & Co. ( B .P . 292,150, 15.6.28. Ger., 15.6.27).
[Arrangem ent of burners in boiler] furnaces for burning powdered fuel. Cl a r k e, Ch a p m a n & Co.,
Lt d., and W . A. Wo o d e s o n (B.P. 323,484, 1.10.28).
Refrigerating m achines. L. Sz il a r d (B.P. 299,783, 29.10.28. Ger., 31.10.27).
A bsorption refrigerating apparatus applicable to ice-m aking. E. R. Mi t f o r d and L. Cr u m p (B.P.
323,815, 13.10.28).
Liquid-distributing devices for gas absorption and like apparatus, particularly for refrigerating.
El e c t r o l u x, Lt d., Assees. of Pl a t e n-Mu n t e r s Re f r i g e r a t i n g Sy s t e m Ak t ie b o l a g e t ( B .P . 303,521, 5.1.29.
A p p l., 6.1.28).
Spraying apparatus. G. El l io t (B.P. 324,117, 1.11.28).
[A sbestos-m etal] packing m aterial [for cylinder blocks of internal-com bustion engines] and its manufacture. H. Re i n z Di c h t u n g s- Fa b r. (B.P.
323,900, 18.12.28. Ger., 3.10.28).
Capsule packing. I. G. Earbenind. A.-G. (B.P.
306,114, 8.10.26. Ger., 17.2.28).
Drying of m aterials (B.P. 297,480).—See IX.
Gas purification (G.P. 457,888). Autom atic titration apparatus (U.S.P. 1,739,230).—See XL Distillation colum n (F.P. 632,450).—See XVIII.
n.—FUEL; GAS; TAR; MINERAL OILS.
Coal rich in spores. Winter seam , N ostell Colliery, Yorkshire. R. G. H. Bo d d y (Fuel, 1930, 9, 38—39).—Microscopical examination of this seam, which a t Nostell Colliery has a thickness of 2 ft., shows it to consist largely (50—60%) of plant residues, e.g., niacerated spores, thick-walled cuticle, and fragments of sporangium wall, which are of the usual type found in durains. The microspores, however, are present mainly in aggregations of crushed spores, quite free from extraneous material. A. B . Ma n n i n g.
M icroscopical study of som ecoalsfrom Szechuan, South-W est China. C. Y. Hs i e h (Fuel, 1930, 9, 'I—19).—Nineteen samples of coal from Szechuan have been examined microscopically by reflected light from a polished surface, after maceration in Schulze’s reagent, and also in thin sections by transm itted light when it was desired to show some special structures. The distribution of the constituents, durain, vitrain, and fusain, the mode of occurrence of the ash, and the character of the plant remains observed in each sample are described in detail. A . B . Ma n n i n g.
Coal cleaning, w ith special reference to Japanese coals. R. L e s s i n g (Fuel, 1930, 9, 20—29).—Nine Japanese coals have been cleaned by a process involving first the removal of the dust and then the separation of the remainder with the aid of solutions of calcium chloride of the requisite density. All samples were subdivided into five fractions of increasing sp. gr., and
the proximate composition of each fraction was deter
mined. All the coals yielded a fraction (70—8 0 % )
containing 3 — 6 % of ash. Carbonising tests at 9 0 0 ° in the Lessing assay apparatus were carried out on all fractions. The coals, with one exception, showed caking properties of gradually descending order as the sp. gr. increased to 1 - 6 0; fractions of sp. gr. greater than 1 • 6 0 were practically non-caking.
A. B . Ma n n i n g.
Fuels. E. St a n s f i e l d, W. A. La n g, J. W. Su t h e r l a n d, K. C. Gi l b a r t, and S . Ze a v i n (Ninth Ann. Rept.
Sci. Ind. Res. Council of Alberta, 1 9 2 8 , 1 5 — 1 9 ).—The slacking of coals on exposure to the atmosphere has been studied under standard conditions; it is found th a t bituminous coals lose 1—5% by wt. as fines, but th a t the losses with sub-bituminous coals are somewhat greater, and with domestic coals are from 4 0 to 1 0 0 % .
Attention has been paid to a number of binders in briquette making, and it is found th a t phosphoric acid is not suitable for this purpose. Ash fusibility has been investigated by using a much larger number of cones than is generally taken, and heating these individually to temperatures a t 2 5 ° intervals; the characteristics of different ashes are emphasised by this method.
R. H. Gr i f f i t h.
D eterm ination of m oisture in coal. T. So m iy a
and S. Hir a n o (J. Soc. Chem. Ind. Japan, 1 929, 3 2 , 2 4 7 — -248 b).—The loss in weight of a coal sample heated at 1 0 5 — 1 10° was determined continuously (1) in still air, (2) in currents of air and of commercial and pure nitrogen and carbon dioxide. The curves show the oxidising effect of oxygen even when present only to the extent of 2 • 5 % as in “ commercial ” nitrogen, and also absorption of carbon dioxide when this latter gas was used. A reliable result is only obtainable with pure
nitrogen. C. Ip.w i n.
Removal of the ash constituents of coal by density separation. B . Mo r y and I. Pe t e r (Szenkis. Kozl.,
1 9 2 8 [1 9 2 7 ], 2 , 1 1 3 — 125 ; Chem. Zentr., 1 9 2 9 , ii, 8 1 5 ).— Fractional separation was effected by centrifuging the powdered mineral (particles < 0 - 0 9 4 mm.) in zinc chloride solution, carbon tetrachloride, and benzene.
The ash of lignite is chiefly embedded between the layers. " A. A. El d r i d g e.
Structure of the ash of coal. B . Mo r y (Szinkis.
Kozl., 1 9 2 8 [1 9 2 7 ], 2, 1 07— 112 ; Chem. Zentr., 1 9 2 9 , ii,
8 1 5 ).—A photomicrographic and A-ray study of
Hungarian coals. A. A. El d r i d g e.
Evaluation of gas coal. II. J. A. d e Go e y and G . A.
Br e n d e r a Br a n d is (Gas- u. Wasserfach, 1 9 2 9 , 72,
1 2 3 7—1 2 4 2 ).—The Geipert method ( B ., 1 9 2 6 , 9 3 8 ) of determining the gas yield of a coal, using a vertical retort, gives results much closer to actual practice than the determination of volatile matter, using a crucible ; there is no constant relationship between the two. The
“ value ” of a coal is the product of the gas yield by the Geipert method and the calorific value of the gas produced. The “ specific value ” is the value per unit of volatile m atter as found by the crucible. These views are illustrated by analytical data for a number of English and German coals. The specific value increases with the age of the coal from cellulose to anthracite or with
B r i t is h C h e m ic a l A b s t r a c t s —B .
2 2 6 Cl. I I . — Fu e l ; Ga s ; Ta r ; Ml k e r a l Oi l s.
reduction in oxygen, content-. The effect of the oxygen content on gasification is discussed in detail and the conclusion is drawn th at the true “ value ” of a gas coal reaches a maximum with 28% of volatile m atter (Geipert method), and then falls to a minimum a t 36%.
The maximum point is approximately that of maximum
methane yield. C. Ir w i n.
Low-temperature treatment of Brazilian coals.
F. W. F r e i s e (Petroleum, 1930, 26, 113—114).—Brazil possesses in the three southern States of Parana, S.
Catharina, and Rio Grande do Sul coal of the lowest Permian formation in five strata, and eight mines are in operation. The evaluation of the raw material by means of low-temperature treatment was investi
gated, and the yields of semi-coke, gas, and tar are given.
In one case washing of the semi-coke gave a product poor in ash which can be compounded with 4% of pitch from the tar distillation to make briquettes con
taining only 4—7% of ash. Tertiary lignite from the regions of Fonseca and Gandarella has a mean content of 45% of water and volatile constituents, 18% of ash, and 37% of solid carbon. Low-temperature treatment carried out at 450° in a revolving furnace produced sandy coke, tar, and gases of an inferior quality.
W. S. E. Cl a r k e.
Coke and charcoal. I. Structure of coke and charcoal. II. Nature of carbon com posing coke and charcoal. III. Reactivity of carbon m aterials.
Y. Os iiim a and Y. Fu k u d a (J. F a c . Eng., Tokyo Imp.
Univ., 1929,18,125—193).—I. Methods for determining the total, open-pore, and closed-pore porosities are dis
cussed, and a new method for determining the open- pore porosity by measurement of the air contained in the open pores is described. The true sp. gr. was obtained by the pyknometer method, using 250-mesh coke and ether. It was found th at the amounts of closed pores in most cokes were small (2—5%), and that the volume of open pores was usually 40—70%.
Microscopical examination of wood charcoal indicated that the distribution of its pores was similar to th at of the original w ood; reasons for the pronounced differ
ences between the microstructures of charcoal and coke are advanced.
II. Finely-ground samples of artificial graphite, retort carbons, oven coke, gas coke, semi-coke, charcoals, pitch carbon, petroleum coke, and active carbon were examined by an A'-ray m ethod; all the samples gave indications of the presence of graphite, the amount decreasing as the temperature of carbonisation fell.
I t is concluded th at coke and charcoal consist princi
pally of minute particlesof graphite contaminated by and cemented together with hydrocarbon complexes. The size and number of these minute carbon (graphite) crystals increase with rising carbonisation tem perature; the nature of coke and charcoal carbon is therefore nearly identical, provided that their carbonisation is effected at the same temperature. Examination of samples of coke taken from various parts of an oven, by the A'-ray method, showed th at “ bottom ” coke was in a more developed stage of carbonisation than “ top ” coke, and th a t the degree of carbonisation progressively decreased from the centre of the charge to the oven wall.
III. The reactivities of a number of cokes and char
coals have been examined by their gasification, in carbon dioxide, at various tem peratures; the amount of carbon dioxide decomposed was determined by a gas interferometer method in which the composition of the gas was obtained from an examination of its refractive index. The conclusions arrived a t are the following :—
(1) The initial temperature a t which coke and charcoal begin to react with carbon dioxide is dependent solely on the maximum temperature of carbonisation a t which the sample is produced, and hence on the state of its carbon (as described above in II). (2) Reactivity is also governed by the nature of the reacting surface ; hence the reactivity of a coke, in general, is independent of its initial temperature of reaction with carbon dioxide.
(3) Reactivity may be affected during the course of an experiment by (a) activation by the reaction itself, due to surface etching and development of microstruc
ture, and (b) deactivation by thermal effects in which the surface atoms tend to arrange themselves in the more stable positions of the graphite lattice, i.e., graphitisa- tion. (4) The surface of high-temperature coke is not as reactive as its inner portion, due to the deposition of stable films from the hydrocarbon vapours evolved during carbonisation; semi-cokes do not exhibit this difference, because their temperature of carbonisa
tion does not effect decomposition of hydrocarbon vapours. (5) The greater reactivity of charcoal is due to its microstructure, which consists of a large amount of surface per unit volume, and to the large number of unstable carbon atoms on this surface. (6) The relation
ship between the effective surface area of a coke and the rate of flow of carbon dioxide necessary to give a definite amount of carbon monoxide in the reaction products can be expressed in the form of an equation ; this can be confirmed experimentally, and indicates th a t an absolute measure of reactivity can be obtained in terms of effective reacting surface. C. B. Ma r s o n.
Coke and charcoal. IV. Form of , carbon com posing coke and charcoal. Y. O s h im a and Y. F u k u d a
(J. Soc. Chem. Ind., Japan, 1929, 32, 208—210 b).—
Various kinds of coke and charcoal were investigated by A-ray methods. R etort carbon alone gave the sharp graphite spectrum ; the other varieties of carbon gave graphite spectra having one or more broadened bands. I t is concluded th at coke and charcoal consist principally of graphite in an extremely fine state of subdivision, but are contaminated to a greater or smaller extent with complex polymerised hydrocarbons. The size and number of these minute crystals of graphite increase with rising carbonisation temperature and corresponding decreasing hydrocarbon content. The results obtained support the non-existence of amor
phous graphite. By Y-ray examination it was found th a t the coke produced in the lower part of a Kuroda coke oven is more highly carbonised than th a t in the upper part, and th a t in each p art of the oven the degree of carbonisation is the higher the nearer is the wall of the oven. I t is confirmed th a t the symmetry of graphite is orthohexagonal. S. K. T w e e d y .
Coke and charcoal. V. R eactivity of graphite.
Y. Os h im a and Y. Fu k u d a (J. Soc. Chem. Ind. Japan,
B r itis h C h e m ic a l A b s t r a c t a — B .
Cl. I I .—Fu e l ; Gas ; Ta b ; M i n e b a l Oil s. 227
1929, 32, 226—227 b).—The reactivity of artificial graphite to carbon dioxide a t 1000° was investigated.
Two surface changes o ccur: (a) the formation of an
“ etched ” surface of highly unsaturated atoms (com
parable with Taylor’s structure for the surface of a nickel catalyst) tending to raise the reactivity of the graphite ; (b) a thermal transformation of the most highly un
saturated surface carbon atoms into a more saturated condition, tending to lower the reactivity. The dimin
ished reactivity of coke is probably due to the deposition of carbon from hydrocarbon vapours on the reactive surface, with consequent destruction of the micro
structure, during coke formation. S. K. Tw e e d y.
Coke and charcoal. VI. Reactivity of coke.
Y. Os ii i m a and Y. Fu k u d a (J. Soc. Chem. Ind. Japan, 1929, 32, 251—252 b).—As coke is composed essentially of minute particles of graphite crystal, the effective surface area (A) of a coke sample can be determined by comparing the rates of flow (F, V ) of a current of carbon dioxide which the sample will reduce to the extent of 50% to carbon monoxide with th a t of a current similarly reduced by a graphite rod of area (A') under similar conditions; then A /A ' = V /V '. The specific effective surface area is this value divided by the weight. A number of such determinations on coke samples are given, and it is claimed th a t the specific effective surface area is a measure of the reactivity. After the tests the samples showed blackening a t the surface, the extent of the blackening being the greater the more reactive was the
sample. C. Ir w i n.
Tem perature changes, heat flow, and heat capacity of coke-oven w alls. M . St e in s c h l a g e r
(Arch. Eisenhiittenw., 1929—1930, 3, -331—338 ; Stahl u. Eisen, 1929, 49, 1797).—The thermal conditions in the walls of a coke oven during charging and discharging hare been investigated; the results demonstrate the greater heat conductivity of silica brick compared with firebrick and the necessity for rapid charging and dis
charging in economising heat. A. R. Po w e l l.
Combustion, wind, and flue equipm ent. C. A.
Ma s t e r m a n (Gas J., 1930, 189, 154—156, 204—208).—
Factors of which a knowledge is necessary for the design of correct flue equipment are discussed. Expressions are given for determining, in a flue of given area, the critical height a t which the products of combustion from coal gas, coal, coke, or oil will be completely removed and sufficient draught provided to meet normal com
bustion requirements. C. B. Ma r s o n.
Liquid purification [of gas] by soda ash solution.
W. J. G. Da v e y (Gas J., 1930, 189, 157—159).—An account of investigations into the Seaboard process of hydrogen sulphide and cyanogen removal by washing the foul gas with a 3% solution of soda ash (cf. Sperr, B., 1922, 359 a ; Cook, B., 1926, 35). Equations are given for the reactions occurring during purification of the gas and activation of the foul liquor by an air- blast. The purification reactions are not so simple as those stated by Sperr, which indicate an efficiency in excess of th at actually obtainable ; it is suggested that the absorption of hydrogen sulphide might be speeded up by replacement of part of the soda ash by sodium hydroxide. The final product from the removal of
cyanogen is sodium thiocyanatc, and profitable recovery of this compound would decrease the cost of the process, and also eliminate a noxious constituent from the ammonia plant effluent ; the commercial possibilities of its recovery as the insoluble copper salt are discussed.
The foul gases from the actifier may either be burned under boilers or rendered innocuous by passing them through an oxide purifier. D. G. Mu r d o c h.
Sulphur production and gas purification. T. P. L.
Pe t i t (Chem. Weekblad, 1929, 26, 542—547). J. H.
Konus (Ibid.. 599). T. P . L . Pe t i t (Ibid., 599).—For removing hydrogen sulphide, coal or coke-oven gas is scrubbed by means of concentrated potassium car
bonate solution, from which the hydrogen sulpiiide is driven out again by carbon dioxide and passed through iron oxide. The oxide after repeated regeneration and re-use is treated with solvents for recovery of pure sulphur. The potassium carbonate solution is heated to break up the bicarbonate formed, the carbon dioxide being thus recovered for re-use. Figures for operating cost and some theoretical considerations on the equi
libria involved are given. A polemical note by Ko e r s
is followed by a reply by Pe t i t. S. I. Le v y.
Desulphurisation of gas with Köflach lignite charcoal. F. Ne u w i r t h (Berg- u. Hiittcnmänn.
Jahrb., 1928, 76, 1—13 ; Chem. Zentr., 1929, ii, 514).—
The use and regeneration of the charcoal are described.
A. A. El d r id g e.
Determ ination of calorific values of producer gas. H. Lö f f l e r (Chem.-Ztg., 1930, 54, 51—52).—A note on the direct-reading Strache -Löffler caloriscope.
S. I. Le v y.
Natural gas. E. H. Bo o m e r (Ninth Ann. Rept.
Sei. Ind. Res. Council of Alberta, 1928, 51—53).—Gas from the Viking field, containing 93% CH4, 3-5% C2II6, and 3% N, has been used as a raw material for thermal decomposition into carbon-black or to low-boiling hydrocarbons. Direct, oxidation processes are found to be of little value, but conversion into water-gas has been achieved. The use of the gas for high-pressure synthesis is considered, and attention is being paid to the removal of sulphur, which is present in large amount.
R. H. Gr i f f i t h.
M icroscopical researches on coal-tar solutions.
F. J. Ne l l e n s t e y n (Gas World, 1 930, 92, 54. Cf. B.,
1 9 2 8 , 3 2 4 ; 1 9 2 9 , 2 3 1 ).—A method of determining the
“ micron number of tar is described. The tar (0 • 2—•
0-3 g.) is dissolved in nitrobenzene to give a 1% solu
tion (by vol.), which is heated, thoroughly mixed, allowed to cool to room temperature, and then filtered through a specified filter paper. The microns in the filtrate are counted in a Thoma hæmocytometer, at a magnification of 4 0 0 ; particles consisting of adhering smaller particles are counted as a single body. The method demands exact standardisation, mainly in respect of the filter paper and of the time interval between the preparation and filtration of the solution.
Solvents other than nitrobenzene; having a surface ten
sion of at least 4 0 dynes/cm. at 2 0 °, e.g., quinoline, fur- furaldehyde, may be used, but different micron numbers will then be obtained. The micron number, which may vary between zero and 6 X 10 7 per mm.3 of tar, assists in
b
B r itia h C h e m ic a l A b s t r a c t s — B .
228 Cl. I I . — Fu e l ; Gas ; Ta r ; Min e r a l Oil s.
evaluating the tar with respect to its binding power, and depends on the origin of the coal, the temperature of carbonisation, and the distillation of the tar, the better tars generally showing the higher numbers.
The test may be regarded as complementary to the ordinary “ free carbon ” test, which is an approximate measure of the micelle content adequate for practical purposes. A more exact value is given by the difference between the values obtained for the precipitates with a liquid of low surface tension, e.g., ether, and one of high surface tension, e.g., nitrobenzene, this difference being the sum of the micronic and ultramicronic micclles.
D. G . Mu r d o c it.
Russian asphalt. E. Gr a e f e (Petroleum, 1930, 26, 101—107).—Petroleum bitumen is produced prin
cipally in Baku from Binagadi crude oil, the charac
teristics of which are tabulated. The oil is blown in a still (capacity 80 tons) at 220—270° with a mixture of steam and air for 2-1 hrs. External heating is unneces
sary as the reaction is exothermic. The yield amounts to 90%, calculated on the residue, and the asphalt yield is 25—30%, calculated on the crude oil ; the latter value is reduced to 15% when straight-run asphalt is blown with steam only. When the asphalt has attained the desired degree of hardness it is passed under pressure from the still to the reservoir, and thence is led to the conveyer. The monthly output of asphalt so produced is 3000 tons. Three methods of obtaining bitumen from the residue from the acid tars from petroleum distillates are described. The acid is removed by washing with hot water and the bitumen compounded with lime and used to produce “ Mastix ” ; or the unneutralised tar is decomposed with hot water (85—
95°) and mixed with air. After keeping for several hours, the separated acid is removed, the operation repeated twice with the residue, and the product so obtained blown at 110—220° with steam and air.
Solvent naphtha can also be used as a means of separat
ing the acid. The bitumen dissolves in this solvent, which can be recovered by distillation, and sulphuric and sulphonie acids remain undissolved. Asphalts so pro
duced are used for electrotechnical purposes, cables, etc., and as road-making material. W. S. E. Cl a r k e.
Extraction apparatus for bitum inous road m ate
rials. F. J. Ne l l e n s t e y n (Chem. Weekblad, 1930, 27, 19).—The ordinary Soxhlet apparatus is modified by elimination of the siphon tube, so th at the solvent runs through continuously. To allow liquid to accumulate in the body of the extractor, if desired, a cock is provided in the connecting tube. S. I . Le v y.
Action of alum inium chloride on hexahydro- arom atic and saturated aliphatic hydrocarbons.
R. St r a t f o r d (Ann. Office Nat. Combust, liq., 1929, 4, S3—108, 317—359; Chem. Zentr., 1929, ii, 1287).—
On treatment with aluminium chloride, ethyl-, propyl-, and butyl- or m-diethyl-cÿcZohcxane afforded, respec
tively, di-, tri-, and tetra-methylci/cZohexane ; o- and p-dimethyl- and cthy!-cÿc/ohexane afforded m-dimethyl- cyefohexane, whilst the propyl compound afforded 1 : 3 : 5-trimethyleycfohexan e. Fission of the side chain is a secondary effect which increases with the length of the chain ; diethylci/c/ohexane afforded butane, n-amyl-
arid •isoamyl-cj/cZohexane gave different yields of methyl- and tetramethyl-ci/cfohex'ane, the iso-compound also apparently producing the pentametlivl compound.
Normal aliphatic hydrocarbons break between the fourth and fifth carbon atoms, giving butane ; a chain containing more than eight carbon atoms breaks at- both ends, forming butane (2 mols.) and an unsaturated residue. Hydrocarbons containing secondary groups are subject to fission and to transposition of the radicals.
The cracking process is attributed to re-arrangement rather than to fission between the nucleus and side chain. Normal aliphatic chains up to C-^Hy and cyclic hydrocarbons with a side chain of C8Hn or C5Hn did not afford fractions corresponding with those of light petrol
eum, which were formed only with compounds con
taining secondary groups, e.g., wobutyl and isoamyl.
The fission, but not the rearrangement, depends on the amount (5—100%) of aluminium chloride employed ; in the cracking of petroleum, using 10—15% of alumin
ium chloride, both reactions probably take place.
Hydrogenation of aromatic hydrocarbons to cyclo- hexane derivatives by Voorliees and Adams’ method was satisfactory unless the side chain contained more than four carbon atoms, when some formation of mcthyl- cyctohexane occurred. Dehydrogenation by Zelinski’s method was employed in a study of the structure of certain cyclic hydrocarbons. Values for the m.p. or b.p., cl, and jid of a number of hydrocarbons are recorded.
A. A. El d r i d g e.
Therm al properties of petroleum products.
C. S. Cr a g o e (U.S. Bur. Stand. Misc. Publ. No. 97, 1929, ‘18 pp.).—Various thermal properties of petroleum products, viz., thermal expansion, heats of combustion, sp. vol. of vapour, thermal conductivity, sp. heat, latent heat of vaporisation, and heat content, are given in numerous tables prepared in forms convenient for use in engineering. These tables embody the results of a critical study of the data in the literature, together with hitherto unpublished data. The experimental basis for each table, and the agreement of the tabulated values with experimental results, are given, as well as empirical equations for their derivation. Each table is accom
panied by a statement regarding the estimated accuracy of the data and by a practical example of the use of the
data. H. S. Ga r l i c k.
U se of organic solvents for extraction of high- sulphur oils from crude petroleum . G . E. Wo o d
w a r d (Ind. Eng. Chem., 1929, 21, 1233—1235).—The
miscibility of 61 organic solvents with Inglewood crude petroleum has been investigated qualitatively, and in many cases has actually been determined, together with the relative amounts of sulphur extracted by them.
Furfuraldehyde, absolute ethyl alcohol, and acetalde- hyde showed the highest concentration of sulphur.
H. S. Ga r l i c k.
Decom position of paraffin w ax on heating. II.
H. I. Wa t e r m a n, J. N. J. Pe r q u i n, and H. A. v a n We s t e n (J. Inst. Petroleum Tech., 1930, 16, 29—33;
cf. B., 1928, 512).—A Rangoon paraffin wax, when distilled at 360° and 385° in an apparatus previously described (loc. cit.), yielded small quantities of hydrogen a t both temperatures and large quantities of unsaturated
