January, 1923
INDUSTRIAL AND ENGINEERING CHEMISTRY
etc. The measuring and weighing devices for the raw materials are such as t o get very accurate results, this being a very important part of the manufacture. The mixing of the acid phosphate and excavating the acid phosphate go on simultaneously. The acid phosphate remains in the den 24 hrs. before it reaches the excavator. Since the construction of the den is such t h a t it is not opened up, the phosphate retains the heat until it is cut. The cuts are about l/8 in. thick when the steam is liberated and drawn off by an exhauster. The thin layer of phosphate, as i t is cut, falls onto angle-iron trays where it is discharged t o any convenient point, its condition resembling sand. The excavator is simply a two-strand elevator with links capable of withstanding the free phosphoric acid present, with angle-iron trays in place of buckets. The capacity of the den is from 100 t o 150 tons per day, but if operating continuously i t is approximately 400 tons per 24 hrs. The den only revolves while the mixing is being done; when completed the den is stopped. The finished product as it leaves the den is very light and contains usually about 11 per cent moisture, with about 1 t o l l / d per cent insoluble P~06,which in a short time rapidly reduces. It is equivalent t o acid phosphate made three t o four weeks by the other methods. There is only one man operating it-namely, the mixer-and either a crane man or car man t o take it t o storage from the den.
87
no difficulty in handling 600 lbs. t o a load on a good floor, and discharging it in the car stacked, obviating stackers unless the car is t o be heavily loaded. This method gives a clean bag with accurate weight. Test bags should be taken at intervals t o see that the weight is correct. The complete fertilizers are delivered to a hopper in front of the bagging machine, requiring one man a t the elevator, one on the machine, one weigher, two sewers, one chute man, two or three tuckers, one tag boy, and, if stackers are used, two additional men. These easily do 200 t o 225 tons per 10 hrs. A modern factory can put out fertilizer in good mechanical condition without harm to the bags, maintaining a uniform output with a very small labor charge; the overhead expenses are not excessive and the upkeep of a well-designed and well-built factory is low, enabling the manufacturer t o produce his goods at the lowest possible cost and make a profit when others fail t o do so. I n days of close competition the old-type factories are at a great advantage as compared with the modern factory.
Hotel Accommodations for the Spring Meeting of the A. C. S.
It is very apparent t h a t the coming spring meeting of our SOCIETYwill be very largely attended, and i t is recommended that all who desire hotel accommodations make their reservaThis is done most economically by the electrically operated tions as early as possible-at least thirty days in advance of the grab-bucket crane of from 2- or 4-cu. yd. capacity. One crane man meeting. The hotel headquarters will be at the Hotel Taft, at one of the factories handles 6000 tons per 10 hrs. with a 2l/~-cu. and the management of this hcstelry advises that reservations for this hotel be made, if possible, ninety days in advance. In yd. bucket. No hand labor or any other mechanical device has case there is an overflow which cannot be provided for with acbeen able t o come anywhere near this when labor and equipment commodations in New Haven, arrangements have been made upkeep are taken into consideration, as it not only handles the whereby guests may obtain suitable reservations in hotels of neighboring cities-namely, Hotel Stratfield in Bridgeport, material but digs it a t the same time. Conn., Hotel Winthrop in Meriden, Conn., and Hotel Elton in Waterbury, Conn. MANIPULATION OF COMPLETE FERTILIZER The committee on hotels and transportation have canvassed very carefully the hotel and apartment house situation and deAccurate weighing is absolutely essential t o success. The in- sire t o announce the following list of hotels, arranging them as accurate weighing of ingredients with consequent overages is nearly as possible in the order of convenient location. one of the chief sources of loss to manufacturers. NEW HAVEN HOTELS Usually, a series of hoppers is elevated so as t o admit of a CAPACITY RATES wide belt being installed t o carry the materials t o the manipulating Single Room Double Room T a f t . . ..................... 400 $3 to $3.50 $5 to $6 or bagging machines, as the materials are discharged from the Garde.. .................... 100 $2.50 up $5 to $6 Duncan.. .................. 100 $2 t o 83 $4 t o $6 scale hoppers and located underneath the storage hopper. Bishop.. ................... 50 $3 $5 The crane or other mechanical device puts the various in- Strand ..................... 40 $1.50 to $3 $3 to $5 $2 (flat rate and for men only) Baths.. ...............l50 gredients into the hoppers, which have close cut-off gates, The Liberty Royal .................... 75 $1.50 (men only) $2 t o $3 scales have large dials so that the operator sees the weight all the time the material is on the scale and can shut off instantly OUTSIDEHOTELS when the desired weight is attained. The scale hoppers are CAPACITY RATES Sin le R o o m Double Room discharged a t a given signal, and refilled for the next batch. Stratfield Bridgeport.. ...... 100 $3.50 $5 to $6 The hopper system calls for fewer men than are generally needed. Winthrod, Meriden.. ........ 50 $2 t o $3 100 $2.50 up $5 to $8 Elton, Waterbury.. ......... The manipulated goods are taken by the crane t o storage and are finally passed through bagging machines. The Hotel Taft offers a special arrangement on the American The manipulating and bagging machines are of various types. plan : The vibrating screens are receiving much attention. Good Double room bath meals 3) $13.00 per day work has been done with the hexagonal revolving screens with Double room: bath: meals { 2 ) $11.00 per day suitable tapping devices. Rapid operation is necessary t o get It is too early for the committee t o make any announcement tonnage; hence, a batch mixer has to be used that will fill, possible accommodations in university dormitories. mix, and empty in a very short time. Automatic weighing regarding It can be stated, however, that the Yale dining hall will be in machines are being extensively used, and little difficulty is ex- operation during the week of the convention. The members of the hotel committee will be glad t o assist in every way possible perienced when the goods are dry. Instead of weighing the bags on the ground floor, this is in the making of early reservations. being done on an elevated platform, with an endless slat conveyor HOTEL AND TRANSPORTATION COMMITTEE located so t h a t as the weigher drops the bag i t falls onto the slat DR. RALPH W. LANGLEY, Chairman, 84 McKinley Ave., conveyor where the bag sewer gets it. The bag travels till it Haven, Conn. is discharged at the end, down a chute, where the chute man di- New PROF. H. W. FOOTE, Sterling Chemistry Laboratory, rects i t onto a truck-three 200-lb. bags or five 135-lb. or six 100- New Haven, Conn. lb. bags being dropped onto a hand truck. The truck man has DR. E. MUNROEBAILEY,621 Elm St., New Haven, Conn.
HANDLING ACIDPHOSPHATE
