REDUCING EXTRANEOUS MAlTER IN CANE LOADED MECHANICALLY

Instead of the cutter placing the three lines of cane in a conThis paper discusses how a marked improvement in cane tinuous windrow, the cane was placed in small bundles about 1 quality was achieved by modification of mechanised loading metre apart. (Interrupted windrow). procedures. The main change made was to cut into stacks instead of windrows thereby avoiding extraneous matter pick-up The 10ader operator then 'picked' UP each bundle until he had which is often characteristic of push-piling. It is estimated that a full grab (usually 3 bundles) which he then h i d e d into the the improvements achieved would have a beneficial effect on trailer. milling performance and throughput and ultimately reduce length of season. Results Introduction As indicated in Table 1 the weekly average cane quality The harvesting system used is hand cutting and mechanical delivered prior to the changes described, i t . before the 18th loading directly into trailers. All the cane is burnt before August, was normally inferior to that delivered by the ~ m harvesting. pangeni grower group. Sucrose was frequently below average while fibre was usually well above average. These conditions The soil can be divided into three types (55% Red Recent were identified on the South African Cane Growers AsSand; 25% Tugela Schist and 20% Wet Valley Bottoms). sociation's cane quality control system in. terms of 'excess mills he topography is undulating with a 30 metre difference ing capacity', and frequent warnings or penalties were advised. between the highest and lowest points. During the 1976177 season, problems were experienced with Subsequent to the changes imp1emented during Week 20 sand and tops in the consignments of cane delivered to the mill. Table 1 shows that sucrose rose significantly above group This resulted in numerous complaints being received from the average, fibre levels dropped steadily to remain below mill mill, and the mill group representative having to inspect the cane average and there was a marked improvement in purity levels as on at least two occasions. The cane cutters were placing 5 lines indicated by the reduced non-POI (and increased sucrose). ~ l l of cane in a single windrow, and a push-piler loader was used to warnings ceased as the cane was not in the default quality range load the cane into the trailers. Because of problems encountered of the quality control system. It is also interesting to note that with loading in steep, wet and awkward areas a Bell loader was the reduction in extraneous matter also led to a marked reducpurchased for the 1977178 season, ~h~ cutting method was also tion in the variability of individual cane test results as shown in changed to the Australian method of cutting where three lines 2to Week 20 the test were are placed in a single windrow. variable within each week as typified by Week 19 with sucrose varying from 16% down to 7,5%, fibre from 13% to over 3 1% Method and purity from 89 to 77. A marked reduction of the test variability was evident subsequent to the changes as shown by The cane quality did improve from the beginning of 1977178 the reduced standard deviation. but sand and tops were still evident in the consignments to the mill. The improvement was due mainly to the fact that the new loader did not pick up as much extraneous matter as the old Observations push-piler. 1. Since the introduction of mechanical loading in 1974175 After attending a symposium on the 18th August, 1977, season the sucrose has been about 1% below mill average, where push-piling was discussed, we decided to modify our whereas for 1977178 season the sucrose was actually above loading technique. mill average (see Table 3).