AT THE HEART OF THE ROAD TRANSPORT INDUSTRY.

Call our Sales Team on 0208 912 2120

Streamlined Street Cleans! Ind Trade Waste Collection

14th June 1963, Page 76
14th June 1963
Page 76
Page 77
Page 78
Page 79
Page 76, 14th June 1963 — Streamlined Street Cleans! Ind Trade Waste Collection
Close
Noticed an error?
If you've noticed an error in this article please click here to report it so we can fix it.

Which of the following most accurately describes the problem?

P. A. C. BROCKINGTON, A.M.I.Mech.E. -1N the four street-cleansing districts of the cleansing superintendent's section of Cardiff City Surveyor's Department, refuse is collected either by individual sweepers using orderly trucks or in some areas by teams of three men using a pedestrian-controlled electric truck. Until March 1 this year, the refuse was transferred to a parent vehicle of 7-9-cu.-yd. capacity for delivery to one of the Department's tipping sites.

Two years ago, a time-and-motion study of street cleansing in these areas was undertaken to obtain a detailed assessment of operating costs and it was decided that the use of a Dempster Dumpster vehicle with multiple containers, located in strategic points to receive the waste, would reduce the number of parent vehicles required and would release part of the labour force, which could then be employed to increase sweeping frequency in certain critical" districts. A provisional estimate indicated that the Dumpster would afford a saving of £2,172 a year.

The results obtained in the practical application of a Dumpster since March I give promise that this estimate was conservative, and future projects include the purchase of a second Dumpster which would work in conjunction with the existing vehicle in the collection and disposal of trade waste. This would line up with the detailed plans made by the Hygiene and Cleansing Department of the County Borough of West Bromwich for trade waste disposal and with the services provided by C. Williams and Sons Ltd., a private haulier of Aston, Birmingham, under contract to the Lucas group of companies, which are described later in this article.

. Manufactured by the Powell Duffryn Engineering Co. Ltd., Cambrian Works, Cardiff, Dempster Dumpster equipment is available with a variety of containers, notably the bottom-dump and tilt types. The container is fully demountable in that it is unloaded from the vehicle to ground level and can, therefore, be parked on the site without the aid of a stand or other type of fixed installation. Twin booms are operated by the vertical hydraulic rams and a third hydraulic ram, mounted horizontally between the chassis-frame members, is linked to a carriageand-skid frame. In the loaded position, the container is located on a forward-sloping bracket to the rear of the carriage, and for unloading, boom chains are hooked to trunnion extensions of the container. The container is then moved rearwards by the combined action of the booms and carriage and lowered to the ground, which occupies a few minutes. A reverse procedure is employed for loading.

For dumping the refuse from a drop-bottom type of container (as currently employed or authorized by the three undertakings mentioned) the container is moved to the rear of the back wheels and is held in position by the carriage, the floor section being lowered by the booms to release the material. With the tilt type the container is tipped rearwards when the booms are lowered, the notable advantage of this type being that the solid bottom obviates spillage of fluid when the vehicle is on the road. Cardiff plans to use the tilt container for trade refuse. which will include waste from abattoirs and sewage pumping stations. The Cardifl containers are of 6-cu.-yd. capacity, mounted on an Austin 6-7-ton chassis, whilst the 8-cu.-yd. container of the West Bromwich outfits will be based on a Bedford TK 7-ton chassis. A Dodge 7-ton chassis is employed by the Williams company for its 8-cu.-yd. containers. Application of the container system to trade waste collection in Cardifl would enable the two vehicles to be used on a joint-operations basis with sufficient spare capacity to provide for an essential service in both cases with one vehicle in the event of a breakdown..

The existing Dempster Dumpster machine is employed in conjunction with 13 containers and an order has been given for eight additional containers. The provisional hourly rate for the vehicle without driver is 12s. 6d., whilst machines will be depreciated -over seven years and containers over 12 years. Sites for the containers include the depots operated by the Department and by the Highways and Works Superintendent, the garages of housing-estate flats, car parks, sports stadiums and so on. The 3-5-cu.-ft. bins of the street orderlies are tipped direct into the containers, full containers being replaced with empty units by the Dumpster driver working without a mate for delivery to the nearest of the three tipping sites, an average distance of about three miles. About 40 containers are emptied a week by the one Dumpster.

The rendezvous system has the disadvantage that the men must leave their beats to meet the parent vehicle, the-timing of which is very difficult in heavy traffic conditions. The parent vehicles formerly employed to collect street refuse were two Dennis Herons and two Karrier Bantams of the side-loading type. Now one Heron and two Bantams are used part-time on the street-cleansing service. Only about 50 per cent of the. Dumpster's nominal capacity is in fact employed, but it collects approximately 60 per cent of the total street refuse.

In areas near the four main cleansing depots, the Harbilt pedestrian-controlled 2-cu.-yd. electric trucks are returned to the depot for emptying, the vehicle being elevated on a taycock 8-ton four-post hoist so that the refuse content can be tipped direct into one of the Scammell articulated trailers, or alternatively the truck is tipped into the trailer from a ramp. Each hoist is fitted with detachable bearers between the two platforms to accommodate the reduced track of the wheels, and this facility also enables the mechanical sweepers to tip their loads into the trailers, which avoids the necessity of driving the machines on to the tipping sites.

The combined length of streets covered by the cleansing vehicles is 322 miles, the total area of the city being about 18,066 acres. Cardiff has a population of approximately 260,000, whilst the number of domestic premises is around 77,000. Amounts of refuse collected from all sources in a day average 300 tons in the summer and 400 in the winter, the total tonnage of refuse taken to the tips normally being about 133,000 tons, including trade waste.

Until recently street refuse in the centre of the city waS collected manually by seven sweepers who delivered the material on foot to the nearby Trade Street depot. The walking time of each man was 3 hr. of the 8+-hr. working day, but the use of electric trucks and parent vehicles was not considered practicable on account of traffic congestion. This difficulty was, however, overcome by employing a Harbilt 760 electric milk float, converted to a refuse side loader with a capacity of 3 cu. yd., which is compact and highly mancruvrable. Six manual sweepers are now employed and the seventh man drives the vehicle round the streets to collect material from the bins.

The main streets are cleansed by mechanical sweepers, which comprise seven Lewins and a Johnston vacuumoperated type. A total of 40 vehicles is employed for refuse collection. which include Karrier Dual Tip 25-cu.-yd. machines, Shelvolce and Drewry Fore-and-Aft 12and 16cu.-yd. collectors and one S.D. Pakarnatic 50-cu.-yd. bulk

loader, in addition to the older side loaders. Of the Department's fleet of 138 machines, 14 are electric trucks. Diesel-powered vehicles are preferred to petrol-engined

equivalents on the score of fuel economy and the longer interval between major engine overhauls.

Although the service offered to industrial concerns for the disposal of trade refuse in containers by the West Bromwich Cleansing Department will not be inaugaurated until July 1 of this year, the scheme has been accepted by at least 20 traders because it will provide a cost advantage in a typical case in addition to improved disposal.

Since the implementation of the Clean Air Act of 1956 and the introduction of restrictions on the disposal of trade waste by burning on open ground and by unsuitable methods of incineration, the Department has introduced the container scheme to compensate traders for the current difficulty of waste disposal and to ensure that unsuitable tipping methods and sites are not employed. Whilst the charges made for the service will cover costs, they are highly competitive and the containers afford a number of factory-site advantages, including a saving in space and general tidiness compared with dumping the waste on the ground.

Upwards of 20 8-cu.-yd. containers of the standard dropbottom universal type will be employed in conjunction with a single prime mover based on a Bedford TK chassis. Dimensions of the container include an overall width of 8 ft. and a height and length of 6 ft., loading doors being provided at the top and both ends. The container's weight of more than a ton is regarded as a favourable feature as it is indicative of its resistance to damage. A full container will be replaced by an empty container at intervals stipulated by the trader, who will be charged a flat rate for hiring and for each collection, refuse being taken to the March Lane tip, an average distance of 24-3 miles. It is emphasized by Mr. S. Cayton, chief public health inspector and cleansing superintendent, that private tips are a potential menace to hygiene and public security because they can attract rats and crickets. Fires may create a hazard, too. None of these criticisms apply to the Department's site.

The County Borough covers an area of 7,172 acres, and refuse is collected by a fleet of 12 Shelvoke and Drewry vehicles from 30,000 premises, the total population of the area being 97,050. In the case of multi-storey blocks of flats (up to nine storeys) refuse is discharged from each floor into chutes, which feed two 1.25-cu.-yd. bins, and collections are made twice a week by an S. and D. 16 cu.-yd. Fore-and-Aft vehicle equipped with a bin lifter.

The vehicle is manned by a driver and loader.

The possibility of using a single 8-cu.-yd demountable container in place of the two bins is now being reviewed as a meaty; of reducing vehicle and labour costs. If the scheme were adopted, one collection a week would suffice and the driver could exchange containers without the assistance of a loader.

The Williams company has been employing two Dempster Dumpster machines for the past six months and has a third machine on order. Essentially the container service provided offers the same basic advantages as the prospective West Bromwich scheme, but there is a greater emphasis on the value of the system in terms of space saving, refuse concentration and so on at the works, and of particular importance enclosing the refuse in a virtually air-tight receptacle eliminates the fire risk when a corn, bustible material is being carried and also prevents spillage on the road.

Normally refuse bins are tipped into the site containers by a rotating head fork-lift truck, and collections are made according to need.

Formerly, conventional types of shortwheelbase tipping vehicles were used for dis posal and were, in the main, loaded by mechanical means or from a chute, but in some cases manually. The saving in vehicle turn-round time by employing containers is relatively small, but it is considered that when the system has been developed to cater for the majority of the refuse it will enable four machines to do the

work of five tippers. Refuse is taken to a number a tipping sites an average distance of 7-10 miles. It is anticipated that within 12 months the amount of rubbish carried in containers may correspond to a rate of 25,000 tons a year.


comments powered by Disqus