It is an independent, self-constituted organization of technical workers and others directly interested in the technical aspect of the South African sugar industry. THE PRESIDENT: This association of ours works under the direction of the South African Sugar A s o c iation.
TWENTY-FIRST ANNUAL SUMMARY OF CHEMICAL LABORATORY REPORTS
As in the case of the boiling house recovery, it has only happened once later than September in the past five seasons. This period To date This period To date This period To date This period To date This period To date This period To date This period To date This period To date This period To date This period To date This period To date This period To date This period To date This period To date This period To date This period To date This period To date This period To date This period T o d a t e.
GENERAL REPORT ON WEATHER CONDITIONS FOR THE YEAR 1945
A characteristic of the latter part of the year was the number of days with very little rainfall or rain. The lack of rainfall was accompanied by a very low average number of rainy days during the second half of the year.
ABSTRACT FROM REPORTS SUBMITTED BY FACTORIES ON THE SEASON'S WORK
27 In the Empangeni district (ie excluding Nkwalini) approximately 95 percent of the sugarcane grown is the Co.281 variety. A characteristic of the Co.281 variety which seems to require investigation is the tendency of three-year-old or older cane to break down in the fields. Thus, the entire consignment is credited to the analysis of the sap which is extracted from the virile cane in the consignment.
And the net result is a fictitiously high assessment of the shipments containing broken stalks and a misallocation of sucrose. Manufacturing.-The prominent feature of the manufacturing process throughout the season under review was the sudden fall in recovery during the August period. which coincided with the supply in quantity of the decomposed cane mentioned above. It is of great interest to see in the monthly laboratory reports from 1945, which the majority of the mills have. registered decreasing extractions compared to last year. It is to be hoped that the drought has forced a most desirable thing, viz. wipe out or severely limit stand-over crops.
NE STATISTICS 1945-46
This superiority of Co.301 over Co.281 is almost entirely due to its better performance south of the Tugela. Indeed, Co.301 outscored Co.281 in every district south of the Tugela except the Port Shepstone area. In the following table the yield of the various ratoons is given compared with 100 as the plant cane crop:—.
Zululand produced a higher percentage of the total crop (36.6 percent) than in the previous two years. This was an indication of the type of cane they had to handle in some factories. In one particular shipment, only 20 percent of the volume of cane was estimated to be good.
WORKING WITH THE CARBONATATION PROCESS UNDER SOUTH AFRICAN CONDITIONS
In the successful adaptation of the process to our special South African conditions, the following factors had a far-reaching influence on the technique of our factory and consequently on the ultimate percentage of recovery of our final product. In view of our particularly difficult conditions, it is gratifying to compare our efficiency for the past eight years with that of the average of the 53 Javanese factories3 which worked through the carbonation process, before the war, as indicated in the juice sucrose balance. sheet. Investigation of the colloids of sugarcane juice and syrup in Natal and Mauritius, I.S.J. 1923-4): The case for the carbonation process in the manufacture of white sugars.
VIGER said he noticed on the flow sheet a gas absorption tower on top of the first carbonation tank. Phosphate, nitrogen and organic matter in the carbonation cake were lower than this. Larger amounts of impurities were eliminated in the carbonation process of the scrubber than in sulfiting.
FIBRE PER CENT. CANE AND EXTRACTION
Thus Uba and Co.290 during the last eight years at Darnall reduced from 28 percent and 30 percent respectively to 3 percent. Under the same milling conditions that have existed for the past eight years, considerable seasonal variations in the fiber percentage, cane had no practical effect on the average crop extractions. The fiber immediately fell by one per cent, and the extraction increased by more than half a per cent., while the capacity of the mill also increased.
Individual mill performance tests showed that the improved extraction was as much a result of the nature of the fiber as it was the total amount of fiber. Dymond's paper, fiber and extraction were given, but not the absorption and grinding rate per hour, and these items could influence extraction and therefore influence the effect of fiber on extraction. The effect of sugarcane fiber percentage on extraction within seasons was much more regular than at present, although some sort of relationship still appeared to exist.
SEASONAL PURITIES OF CANE JUICES
The quality of non-sugar substances and their effect on processing is a much more complicated topic, since we do not have enough knowledge either about what they are or about the extent of factors such as the age of the cane, the time between cutting. and milling, physical condition, soil and weather, disease and variety may affect the amount of any of them. Thus, at Darnall, Amatikul, and Felixton, the difference between crusher juice purity and blended juice purity, as well as the difference between blended juice purity and processing, varies significantly from year to year. In the four representative centers of the sugar belt, the simple average purities of the first and second half of the thirty-year period are the same.
These can be caused by the qualities of the non-sugars, which are affected by factors such as cane age, time between cutting and milling, physical condition, soil and weather, disease and variety. Similarly, the quality of the non-sugars was largely responsible for the boiling house recovery that could be achieved. RAULT found it difficult to mathematically assess the effect on recovery of small fluctuations in purity, but in general the purity of the juice, i.e.
MECHANISATION AS APPLIED TO THE SUGAR FARM
A retractable point is attached to the toe of the standard with the back wings about 6 to 8 inches above its lowest point. This unit is portable and water can be sprayed up to 200 feet on either side of the furrow. The capacity of the existing harvesters, approximately 200 tons per eight hours, is too much for the average planter and would mean a drastic reorganization of the transport system for the large planter.
The yield is based on an average of 25 tonnes per hectare for each of the three crops, and total preparation costs are charged to the total yield. The CHAIRMAN said that this document was most appropriate in view of the rising cost of labour. Some existing types of loaders could be modified to make them suitable for sugarcane loading.
IRRIGATION FOR THE INCREASED PRODUCTION OF SUGARCANE
Next comes a column for the "average" of these measurements, which is worked out in the irrigation office, just like the rest of the columns. However, the costs of operation and maintenance in the latter case are far higher than those of the former. The high cost of steam-electric water is due to the large overhead costs associated with maintaining qualified mechanical and electrical personnel.
On the contrary, they are allowed to float to the sea and carry the very lifeblood of the land with them - the land. The water particles were so finely divided that it facilitated evaporation, and this process was further aided by the fact that a great deal of water adhered to the leaves of the cane. He believed that the best way to water was to get the water to the roots of the plants.
A REVIEW OF THE PRESENT SUGARCANE VARIETY AND DISEASE POSITION
The presence of large quantities of the wild grass Setaria sulcata with mosaic disease in the affected area suggests that there is a natural source of infection from which the disease can be acquired. Of minor diseases, Co.281 is susceptible to brown spot, which sometimes, especially in the colder months, gives the fields a brownish appearance, and under these conditions is likely to cause some damage by disrupting the normal photosynthetic activities of the grass. the leaves. Co.301 is particularly sensitive to rust and causes some damage of the same nature as the brown stain on Co.
This aspect of the disease problem was also observed during the red rot position investigation in Eshowe, in which it was observed that the most affected fields, e.g. The presence of root rot has been mentioned in Co.281; This disease, indeed, seems to be one to which this variety is proving susceptible. Of the other commercially grown varieties, Co.331 has not been reported with any diseases other than the mosaic already mentioned, and the pineapple disease;.
THE REJUVENATION OF OLD RATOONS BY MEANS OF AMMONIUM SULPHATE
REPAIR OF OLD RATONS BY MEANS OF AMMONIUM SULFATE. for the same series in cane culture. In like manner, the number of sulphate of ammonium in the past, would now take 200 lbs. Assuming this to be the case, if the treatments had not been changed, the overall mean percentage might have been of similar proportions in the third ratoon crop to that found in the second ratoon crop.
T he aftereffect in the case of this particular crop appears to be in the region of 4 tons per acre, or about 12 percent. The results of the third ratoon crop are given, illustrating a reversal in fertility attributed to the change in the amounts of ammonium sulphate applied. He wondered if any information was available here on the effect of the nitrogen-potash ratio on the growth of sugar cane.
THE FOOD PRODUCTION DRIVE AND THE SUGAR INDUSTRY
If the vegetable matter can be hay or something of considerable fodder value in itself, so much the better, but it is not always considered absolutely necessary. The quantity of dried vegetable matter to be added to a given quantity of molasses will of course vary according to the absorbent nature of the vegetable matter used and the density of the molasses. The feed mixture must be dry enough to be transported in bags and if it has a granular texture it is easy to handle when used.
It is very unusual for a farmer to be able to get molasses this way, and most farmers who have to transport molasses from the rail to their farms by road can't carry as much as a tank truck at a time, so they are forced to make do with what little they get in the drums. This station should also look at what extra substances needed to be added to get a properly balanced ration. As a dry fiber to be mixed with molasses to make a meal, he suggested the ground shells of monkey nuts, which were plentiful in the northern Transvaal.
INSTRUCTIONS TO AUTHORS
