Tobacco Documents Online

CHARGE NUMBER : 1503 PROGRAM TITLE : Modified Smoking Materials PERIOD COVERED: July 1-31, 1981 PROJECT LEADER: G. D. Keritsis f C I. RCB STUDIES (J..W. Leik)1 Laboratory studies indicate that the homogenization of production RCB slurries with a Gaulin homogenizer (one pass) increases the RCB sheet tensile by'35-40%, and that the addition of 2% NaCMC (DWB) to the homogenized production slurry increases the sheet tensile by an additional 20-40%. The latter increase was obtained with the addition of 2% NaCMC 7HF, a high molecular weight/viscosity gum. This study is now being repeated with stem-free RCB slurries and with RCB slurries containing bright stems in place of burley stems. A larger run at the BL Pilot Plant will also be attempted to produce larger quantities of RCB with 2% CMC for testing. II. WATER EXPANSION (H. H. Sun)2 In an effort to generate data for scaling up the WET process, four a3ditional trials were made at Westab (24" tower) with uncased DBC bright filler at .. 28% feed OV (as cut). In these trials the feed rate of the wet tobacco_to the tower was 1000 aad•2000 lbs/hr, the tower inlet temperature was 62'5° and 675°F, and the process gas velocity varied between 140-167 ft/sec. At these conditions the tobacco was partially expanded (eq SV = 1.4 - 1.8 g/cc, eq CV - 53 - 71 cc/10 g). The higher values were achieved with the lower feed rate (1000 1bs/hr) and higher tower temperature and gas velocity. At these conditions, however, the expanded tobacco was "toasted" and had a pronouned salt and pepper appearance with the darker tobacco having an eq. SV - 3.9 cc/g and the ligher portion having an eq SV - 1.7 cc/g,yielding an average eq SVgg - 2.11 cc/g. The fillers produced in these trials will now be evaluated in blended cigarettes. Indications are that bright expands to a higher eq CV than burley, and that there is a tendency for the lower stalk position bright to expand to a higher eq CV than the top stalk position bright. This, however, was not evident with burley. One mode of applying the WET process is to dry the entire blend at the primary using a tower in place of the ADT dryer to increase the blend CV to over 50 cc/10 g. Such a trial was made with freshly cut Marlboro filler at 26% OV in the 3" tower at 550-650°F in the presence of steam. In this case, the blend eq CV was increased from 32 to 52 - 66 cc/L0 g, and the eq SV'increased from 0.89 g/cc to 1.3 - 1.6 g/ec depending on tower treatment temperature. The treatment time in all cases was - 1 second. The same filler that was conventionally dried (ADT dryer) reached an eq CV of 35 cc/10 g. It is of interest to note that the tobacco expands further with a second pass through the 3"' tower at its exit OV from the first pass. This is illustrated by the following: a 20% feed OV DBC bright that was treated in the 3" tower at

2 650°F exited the tower at 1% OV and achieved an eq SV' = 2.0 and an eq CV = 69 (eq OV = 11.5%). When this filler was fed to the 3" tower at the same temperature (650°F) and at 1% OV, the filler properties increased further as follows: eq SV - 2.9 and eq CV = 103 (eq OV'= 9.8%). This indicates that a major degree of expansion is still achieved when the filler reaches a very dry state and that the WET process expansion mechanism may not be entirely due to water. An effort to study this is in progress. III. FUNDAMENTAL STUDIES A. Denitration of Tobacco by Chemical Means (S. E. Wrenn)3 It has been found that the treatment of tobacco (burley stems) with hot formic acid fumes significantly reduced the N03-N level in tobacco. Attempts to scale up the process for treating burley strip by this non-extractive denitration process are underway. B. Self Extinguishing Cigarette (N. B. Rainer)4 Based upon preliminary observations on hand-made cigarettes, it appears that treatment of cigarette paper with a DAP/Na-tetraborate solution causes the coal to have less tendency to ignite any material the cigarette is in contact with. This information was passed on to Dr. A. Kallianos for his studies. C. Tobacco Stiffening (N. B. Rainer)4 It has been found that the addition of 1% Ca to bright tobacco filler causes a 10-30X CV increase. The Ca is added as Ca(OH)2 into the bright casing used to case the filler. IV. REFERENCES 1. J. W. Leik Notebooks Number 7395 and 7644. Z. H. H. Sun Notebook Number 7379. 3. S. E. Wrenn Notebook Number 7621. 4. N. B. Rainer Notebook Number 7278. ti, ~A"vv-~ /deb