Faster bulk transport may bring new look to refuse disposal
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EVELOPMENTS in road and rail r transport with the emphasis on faster,
r movement, not only in congested towns cities but in moving from town to ntry, all of which might call for a new look ttulk haulage of refuse, were among the jects discussed at the Institute of Public ansing Conference held in Bournemouth week.
he reduction of bulk by incineration or iposting, the possibility of increases in and speed of long distance vehicles in 7 road conditions, also fast motorway rel, could bring potential distant tips so
nearer in the time element that they ,ht present much more reasonable nomic propositions. The use of standard ge railway trucks for hauling refuse .1d perhaps once more become attractive he reorganized railway systeni as a means taking up spare track and engine time. , Bevan was speaking on "The Science I Practice of Controlled Tipping".
tefuse disposal in Greater London was isidered in a joint paper by Mr. E. H. k, director, Department of Public Health ;ineering Greater London Council, and . F. L. D. Flintoff, assistant director fuse Disposal) Department of Public Ilth Engineering Greater London Council. :y were already confident that the decision provide regional disposal for London's Ise was right. For the first time in the ory of this country a capable and Llified team was engaged, in the words the Royal Commission, on "systematic :arch into methods and costs of refuse )osal including transportation" and the t steps had been taken to "earmark and :guard the land required for tipping, to ;et a positive programme of land reclamaand to organize transportation".
)n March 31, 1965, the last day before London Government Act took effect, Ise disposal in the Greater London area being administered by 90 local authorities I 2,877,000 tons of refuse were being idled annually by various means. Transt of this refuse to tips was mainly by road 653,000 tons went by barge and 195,000 s by rail. All railing and barging was lertaken by contract; the bulk transters were operated in some cases by local horities and in others by contractors.
3u1k road transport of refuse was a field which little criticism could be levied and was certainly because at least three nufacturers had devoted much time, )rt and skill to ensuring that even light ise could be compressed sufficiently to ble a vehicle to carry an economic load. :h ever-falling densities, however, there ; little doubt that the vehicle which ried 12 tons today could be carrying only it tons in ten years time. A possible eption was the MPL system for which there was evidence of fairly constant bales, regardless of initial density. The steady fall in the density of refuse posed continuing problems in the design of bulk transport. Solution of to-day's problem was no guarantee that the effectiveness of compression would continue to maintain economic loads into the 'seventies and 'eighties.
Where refuse was transferred from the collection vehicle to bulk transport it would be a great advantage if, at that point, the character of the material could be changed in a way which at least increased its density substantially. The connection between this problem and that of treating material for controlled tipping was inescapable. However, one perhaps could jump too readily to the conclusion that it must be right to install pulverizing plant at transfer stations not only to produce a more suitable material for controlled tipping but, if possible, to achieve an economic load in a conventional vehicle without expensive compressing machinery.
Much work to he done
Much work remained to be done in this field but the following probabilities were beginning to emerge: (a) crude refuse pulverized in a hammer mill could initially occupy more space after treatment than before but very gentle compression would be sufficient to effect a density of twice or more that of the original material, (b) pulverization incorporating the addition of water at about 40-gal. per ton eliminated any tendency to flocculation and might result in a density 2+-3 times that of the original material. Present indications were that the cost of pulverization would not be fully recovered in the form of reduced road transport costs but the real justification for the treatment lay in controlled tipping needs.
A factor which it was thought necessary to .determine as soon as possible, because of the danger of conflicting interests between the boroughs responsible for collection and the Greater London Council for disposal, was the distance from the collecting point at which the transfer of refuse to bulk haulage became economical. Little had been published on this question and existing practice varied widely, some authorities effecting transfer for hauls of five miles or less. A preliminary assessment was attempted by taking a number of examples and arithmetic indicated that it was unlikely to be profitable to effect transfer for a haul of less than eight miles; the optimum distance could well be 12 miles for a single journey.
This question was thought to be one of great importance. Accordingly, the newlyformed operational research unit in the Greater London Council had been asked to make a full investigation and to produce a formula which would take all the variables into account in considering each particular situation.
Motorized age
Public cleansing was now in an era of compression vehicles, dustless and semi-dustless loading, mechanical and suction sweeping, said Mr. A. C. French, director of cleansing, Falkirk, in his presidential address. The improvements would amaze many former officers who had not been able to witness the transformation. In this motorized age it was imperative that steps be taken to ensure free flow of traffic in town and country alike. Plans and effort must be applied to deal expeditiously with the snow hazard.
Many local authorities provided a firstclass service but too often it was the failures that were publicized without proper inquiry into the many other successful operations carried out. Nevertheless, the service must do better and be prepared for the recurring headaches produced by severe weather. Such work might be costly, said Mr. French, but against this had anyone counted the cost of traffic delays, vehicle damage and human effort necessarily involved in times of snow and frost?
A rotating-drum 50 cu. yd. refuse collector was a new feature shown by Ronald Perham Ltd. at Wednesday's demonstration. The Shark is a continuous loader to a design developed by the Kuka organization which has worked on this system on the Continent for nearly 40 years and the latest model has been in operational use for the past four years. It is specially intended to deal with very low-density urban refuse.
The demonstration unit was seen on a Mercedes-Benz chassis. When bins are emptied into the hopper at the rear the elevating ribs carry the refuse to the main drum entry into which ills forced by a new type of guide; the refuse cannot return and the hopper is therefore continuously emptied.
Shown by the SMT organization was the Raynor 20-ton-payload tipping trailer, which, it was stressed, is particularly suitable for bulk refuse haulage. Another unit in the demonstration was the BennesMarrel multi-bucket outfit, shown by CAF Mechanical Handling Equipment Ltd. Rolba Ltd. demonstrated a Rolba-equipped
Unirnog snow clearer. A.T.