PRODUCT AND PROCESS DEVELOPMENT
Preliminary Cost Study of Rice Wax Filtration-Extraction JOSEPH POMINSKI, K. M. DECOSSAS, P.
H. EAVES, H. 1. E.
VIX, AND E. F. POLLARD
Southern Regional Research Laborafory, New Orleans, La.
A
MODIFICATION of the filtration-extraction process which permits the simultaneous recovery of oil and wax from rice bran has been developed on a bench scale and has been previously reported ( 9 ) . Though no industrial filtration-extraction plants for producing rice oil are in existence today, commercial application of this process to other oilseeds (I, 6) and successful pilot plant runs on rice bran (7) show that the process can be extended to the commercial recovery of oil from rice bran. The purpose of this paper is to present a preliminary cost study of the application of the modified process to rice bran as an indication of the commercial feasibility of recovering rice wax from rice bran. Rice wax, with a potential domestic production of approximately 750,000 pounds annually, based on 1,000,000pounds of wax calculated from total U. S. rice production figures for 1952, compiled by Rice Millers Assn., and published in The Rice Journal (,January 1953), is a possible replacement for imported vegetable waxes for many uses. The United States imports practically all the hard vegetable waxes it uses in polishes, carbon paper, food wraps, and vegetable coatings, and for the past 10 years the imports have amounted to over 20,000,000 pounds per year. Xn 1951, 26,340,000 pounds of vegetable waxes valued at $21,082,000 were imported, approximately a/+ of which was carnauba worth an average price of $0.929 per pound (IO). Flow diagrams and material balance
Figure 1 shows the filtration-extraction process for recovery of only oil from rice bran (7'). Figure 2 shows the proposed process for the simultaneous recovery of wax and oil by filtration-extraction with additional equipment needed for wax recovery except the refrigerating system. The proposed flow sheet was based
on optimum conditions for bench scale work previously reported (9). I n the process rice bran is extracted with cold hexane a t 40' F. to remove oil, followed by a hot hexane extraction t o remove wax, both operations being conducted on a single continuous horizontal filter. Wax is recovered by cooling the hot wax miscella to 40' F., separating the precipitated wax by centrifugation, and desolventizing the solvent-wet wax by evaporation and stripping. Oil is recovered from the oil misceua by conventional means. The bench scale method on which this process is based gives a hard brown wax product that has a high melting point of approximately 79" C. and has the ability to take a high polish. Table I shows a material balance for a 100-ton-a-day rice bran processing plant employing the filtration-extraction process for simultaneous recovery of wax and oil. I n this plant 500 pounds of wax would be recovered while recovering over 28,000 pounds of oil.
Table 1. Material Balance for 100-Ton-per-Day Rice Bran Processing Plant Employing Filtration-Extraction Bran 13% HeO, 14.67% lipids, 0.333% wax Oil i i bran
Wax i n bran Final meal, 10.0% H20, 0.59% lipids, 0.104% wax Oil in final meal Wax in final meal Solvent in marc, 33.3% Oil extracted Wax recovered Miscella in eva orator, 13.79% solpent loss, Moisture evaporated
1.8%
Solvent-bran ratio
Pounds 200,000 29,833 667
161,240 949 167 80 620 28:384 500 205,764 2,000 9,876 1 . a t 1. o
Estimated plant investment costs are shown
,
I+l
I
I[-
CONTINUOUS FILTRATION EXTRACTION
i 1
l
-
Figure 1.
October 1955
l
MARC-
i ,, l J
d
'L_-3-J
OIL HEXANE OIL R EGOVER Y SYSTEM
OIL
I
HEXANE
c
I
[
HEXANE
DRYER
1
1
MEAL
Filtration extraction of oil from rice bran
Table I1 shows estimated additional equipment and costs needed t o convert a plant extracting 100 tons of rice bran a day producing oil only to one that would simultaneously produce oil and wax. Equipment costs were based on the flow diagram shown in Figure 2, on quotations received from equipment manufacturers, and on published information (9,4,8). I n such a plant there would be no need for additional buildings other than a cold room. Facilities already located such as steam, water, and electrical services should be sufficient or require little change. Major additional equipment required would be a refrigerating system, a cooked meal cooler, a crystallizer to cool wax miscella, a centrifuge to separate wax, wax desolventizing equipment consisting of an evaporator and stripper, heat exchangers, and accessories. These figures are estimated additional costs for a plant that would be processing rice bran for oil by filtrationextraction. Presently, none of the rice bran extraction plants use the new filtration-extraction process; therefore, no costs for rice bran extraction using this method are available. However, they should approximate preliminary costs reported for the filtration-extraction of cottonseed (8).
INDUSTRIAL AND ENGINEERING CHEMISTRY
2109
PRODUCT AND PROCESS DEVELOPMENT Table II.
Estimated Additional Equipment and Costs
A. Refrigerating unit, 40 tons a t $400 per ton installed, including cooling tower, pump, labor for installation, a n d piping B. 5 H e a t exchangers for heating or cooling solvent a t $400each C.
D.
$ 16,000
2,000 5,000
Cr atallizer for cooling wax miscella
Cord room, includes materials, insulation, labor, a n d refrigeration of 3 tons
Centrifuge P u m p for centrifugal liquid discharge Evaporator and accessories, desolventizing equipment based n _ n_ nnntinnnnn ___ __ nnpration .=.~_ ... a. Strippef, desolventizing equipment I. Insulation of filter and slurryer Inatrumentation of centrifuges, and desolventization equipJ. ment K. 3 Pumps a n d 3 tanks for extra washings on t h e filter L. Installation of pentrifugals a n d deeolventization equipment M. Meal coolers N. Other expenses-i.e., piping, utility (20y0A through M)
E. F. G.
15,300 13,550 2,350 2.500 1,000 2,000 900 1,650 1,685 10,000 12,385
74 320 13:OOO
17% for contingencies
large pilot plant scale operation should show whether costs will increase or decrease
The estimated additional costs shown were based on available laboratory data and current equipment prices. Further engineering and development may either reduce or increase the costs. Large pilot plant scale work may indicate that cooling of meal is possible in the slurry mixer instead of in an additional expensive meal cooler, water washing the miscella may be advantageous, and the amount of operating refrigeration may be changed by the heat transfer characteristics exhibited on the filter and by the type of crystallization used (fast or slow). The expense of an evaporator and stripper for the wax desolventizing system would be greater if the operation is intermittent. The wax product obtained would have a brown color; bleaching this wax to a lighter color should cost approximately an extra $0.05 per pound.
87,320 13,100
0. Engineering expenses, 15% X 87,320
$100,420
Total additional costs
Net additional return i s the difference betw-een total income and total costs
A break-even chart (profit-loss chart ( 5 ) is shown in Figure 3 for the rice wax phase operation of a 100-ton-per-day plant. This chart is based on a return of $0.55 per pound for wax and includes all cost with the exception of federal income taxes. Fixed costs which do not vary with the amount of rice bran processed appear as a straight line. They include plant maintenance, overhead, depreciation (&year write-off ), interest rates, insurance rates, and tax rates (%, 11). Variable costs show as a sloped line and include solvent loss, labor, power, and water costs. Additional labor costs are estimated for the production of the wax, but it may be that the labor normally used in the extraction plant would be sufficient for production of wax. There is practically no additional materials cost, only the cost of greater solvent loss due to increased materials handling. Variable costs added to fixed coat give total costs. The difference between total income and total costs is net income. The break-even point is the point where the total costs line crosses the total income line. The break-even point for a 100-ton-per-day plant is about 105 days (g), and the chart shows an approximate net profit of $22,000 for plant operation of 250 days. This profit was based on a price of $0.55 per pound for wax; however, for a price of $0.75, which appears probable, the profit would approximately be doubled to $44,000.
Rice oil producer income should increase substantially despite added investment and operating cost to produce wax from rice bran
A preliminary cost study based on bench scale data and current equipment prices has been made for the commercial filtrationextraction of rice bran to produce rice wax. Estimated cost and profits for producing rice wax by a new process in which wax and oil are simultaneously and separately recovered from rice bran by filtration extraction are given. This preliminary estimate indicates that the additional investment and operating costa required to produce wax from rice bran are reasonable and that the process could considerably increase the net income of a rice oil producer. Acknowledgment
The authors wish to express their appreciation to E. A. Gastrock, Engineering and Development Section, under whose general supervision this work was accomplished; R. M. Persell, Office of the Chief of Branch, for his technical assistance; and G. I. Pittman, Engineering and Development Section, for making the drawings.
RICE B R A N
WAX FRE RECOVERY OIL
EXANE
1
HEXANE STRIPPER
]
MISCELLA
DRYER
1
HEXANE-
M AL
1
WAX
Figure 2. Simultaneous production of wax and oil from rice bran by filtration extraction 2110
DAYS OF OPERATION PER Y E A R
Figure 3. Break-even chart for rice wax,production b y filtration extraction in 1 00-ton-per-day bran plant
INDUSTRIAL AND ENGINEEBING CHEMISTRY
Vol. 4'1, No, 10
PRODUCT AND PROCESS DEVELOPMENT L. J., and Spadaro, J. J., J . Am. Oil Chemists’ SOC.,30, 139-43
literature cited
(1953). (8) Persell, R. M., Pollard, E. F., Deckbar, F. A., Jr., and Gastrock, E. A., Cotton G i n & Oil Mill Press, 53, No. 17, 18, 20 (1952). (9) Pominski, J., Eaves, P. H., Vix, H. L. E., and Gastrock, E. A., J . Am. Oil Chemists’ Soc., 31, 451-5 (1954). (10) Sayre, J. E., and Marsel, J., Chem. V e e k , 71, No. 13, 29-50 (1952). (11) Spilsbury, C. C., “Marketing and Processing Costs of Cottonseed Oil Mills in the Post War Period, 1946-7 to 1950-1,”p. 32, U. S. Dept. Agr., Production and Marketing Adm., Fats and Oils Branch, Washington 25, D. C., 1952.
(1) Andrews, J. P., and Kurtz, A. E., Cotton G i n & Oil Mill Press, 54, NO.24, 12, 13,37-8 (1953). (2) Brewster, J. M., “Comparative Economies of Different Types of
Cettonseed Oil Mills and Their Effect on Oil Supplies, Prices, and Return to Grower” U. 5.Dept. Agr. Marketing Research Rept. 54, 107-9 (1954). (3) Chilton. C. H., Chem. Eng., 56, No. 6, 97-106 (1949). (4) “Data and Methods for Cost Estimation; A Collection of Articles from Chemical Engineering,” McGraw-Hill, New York, 1946-52. (5) Gastrock, E. A.,Persell, R. M., and Pollard, E. F., Cotton Trade
J.,34, No. 49, 6 (1952). (6) Gastrock, E. A., Spadaro, J. J., Gardner, H. K., Knoepfler, N. B., and Molaison. L. J., Oil Mill Gaz., 59. No. 2. 40-1
RECEIVED for review December 9,1954. ACCEPTED March 26, 1955. One of the laboratories of the Southern Utilization Research Branch, Agricultural Research Service, U. S. Department of Agriculture. Presented a t the Southeastern Regional Meeting, ACS, Birmingham, Ala., October 21, 1954.
(1954). (7) Graci, A. V., Jr., Reuther, C. G., Jr., Eaves, P. H., Molaison,
Ozonolysis of Alpha-Pinene FRANK HOLLOWAY’,
H. JOYCE ANDERSON,
AND
WALTER RODIN
Armour Research Foundation o f Illinois Instifufe of Technology, Chicago 16, 111.
T
-
HE discovery that the esters of pink acid (2,2-dimethylby the ozonolysis of a-pinene in the liquid phase using concentrations of ozone up to 100%. The structural formulas of the 3-carboxy-cyclobutylacetic acid) have excellent lubricant (8) and plasticizer (3, 6 ) properties has stimulated interest in this principal compounds are compound and in its precursor, pinonic acid (2,2-dimethyl-3acetylcyclobutylacetic acid). The cost of producing these acids by permanganate oxidation of a-pinene to pinonic acid and furtheis oxidation to pink acid with hypochlorite is expensive. On the other hand, an ozonolysis process might be developed 02* which would be economically attractive. Harries and coworkers (6)made a cursory investigation of the ozonolysis of a-pinene and reported about 25% yields of a liquid pinonic acid. Subsequently Brus ( 9 ) obtained low yields of solid optically active pinonic acid PINENE PlNONlC ACID PlNlC ACID by decomposition of an ozonide of a-pinene. More recently, Spencer and coworkers (9) have reported that vapor phase ozonization of aTable I. Effects of Solvents and Post-Ozonization Methods on Pinonic and Pinic Acids Yields pinene yields an ozonide conOzonization Conditions taining five atoms of oxygen Pinene 10 ml. Carrier gas Nitrogen which yields pinonic acid. Ozone a t 10% level 1 gram Fritted glass pencil gas dispersion unit They question the validity Ozone a t 5% level 0.5 gram Ozone flow rate 10 l./hr. of Harries identification of Ozonization Oa pinonic acid. Post-Ozonization mole Temp., Yielda, Prior to the initiation of Method Solvent MI. % c. % Special Conditions the research reported here, Standard aq. HzOz added, Acetic acid 30 10 25 46,49b Oz carrier gas refluxed 2 hr. Acetic acid 20 10 25 315 Perforated glass tube gas workers at the Naval Stores He0 1 dispersion unit i n pinene phase; 50 ml. Station of the United States Acetic acid 26 10 0 27 pinene Department of Agriculture, Methyl alcohol 4 Acetic acid 30 10 25 23 Southern Utilization ReIDreozonizedl search Branch, had verified Acetic acid 28 10 25 33 Acetic anhydride 2 the fact that pinonic acid is Reduced in volume t o CCL 30 5 25 58b actually obtained by liquid about 5 ml. b y heating CClr 30 5 25 68,666 over water b a t h and then 2 phase ozonolysis of a-pinene refluxed 2 hr with standacid 30 5 2 5 50 ard HzOz -’ CHICOOH ~ ~ acid ~ ~ 2 i c using low concentrations HzO solution (295) of ozone ( 4 ) and had Ethyl acetate 30 5 25 24 increased the yield of pinonic Ethyl alcohol 30 5 0 14 Methyl alcohol 30 5 -12 51b acid to about 5070. This Chloroform 30 5 0 53 Perforated glass tube diswork consists of a broad Acetic acid 2 persion unit 30 10 25 276 Total ozonized system Nitro methane screening program of the heated for 5 hr. over 25 28 effect of a number of variwater b a t h and then H ~ ~ ~ ~ ~ l u 30 o r o lo vigorously refluxed 2 hr. 2 ables on the production of withstandard HnOt-CHs30 5 25 36 COOH-Hz0 solution pinonic acid and pinic acid Acetic acid 2
8 bo*” 6
2:k:
1
Present address, Air Products,
October 1955
:;r
a Combined percentage yield of pinonic acid and pinic acid based on amount of ozone used. acid t o pinic acid approximately 9:l. b Best of multiple runs.
INDUSTRIAL A N D ENGINEERING CHEMISTRY
Ratio of pinonic
2111
