The Selection and method of employment of Landfill Site Mobile Operational Plant is an important topic for any landfill operator and getting this right can provide a boost to the bottom line profitability of a site while by ensuring good high density emplaced waste with good compaction giving reduced settlement and minimal potential instability problems for the final landfill shape.
Bomag Landfill Compactors
Where wastes are tipped on top of each bay in the landfill cells the plant is used to push the refuse into position over the tip face after discharge from the vehicle. A skilful operator whilst doing this will, by keeping his blade slightly above the intended level, roll the bulk of the refuse in front of him and leave the dust and cinder as a layer behind him.
This method means that the refuse is compressed by the weight of the bulldozer as it advances and also by the weight of vehicles delivering refuse to the tip face. Wheeled vehicles, of course, are cheap to buy and run and are capable of a greater compressing effect than a tracked vehicle as their weight is not spread out as with tracked vehicles.
Where wastes are tipped at the foot of the bay the operation of the tractor in forming the sub-layers is an upward motion and it is fairly common practice to operate the tractor continuously as it forms the sub-layers, thus producing greater compaction, albeit at the cost of increased wear and tear on the machine.
Choice of Machine
Tired wheeled vehicles possess the advantage of versatility, in addition to their comparatively low cost compared with other forms of traction, in that they can be used to trim and cover the tip face; to dig and load cover material from other parts of the site with little time lost in travelling; and to travel on the public highway to other tips in cases of emergency, or to local depots for garaging and possibly other work.
Point loading also gives this type of machine good compressibility capability to compact the waste well.
All these features together with relatively low cost make tired wheeled vehicles good standby machines in almost any organization.
The disadvantages are a limitation on capacity, less efficient initial settlement and levelling, and a puncture and physical damage problem, although this can be partly solved by using solid and filled tires.
The tracked machine is more costly to buy and maintain than the tyred wheel machine but can work under conditions which would be impossible for a wheeled machine. Although compressibility is not so good, improved levelling can be achieved, especially when a blade is fitted, and the same machine can haul a scraper for soil stripping, stockpiling and replacement.
The use of shovels, as opposed to blades, on tractor equipment has become almost universal because of their capacity to dig material and to be used for loading. A further development is the 'four in one' shovel ( commonly called by its original UK manufacturers name of JCB) which, in addition to digging and loading, can also be used as a grab to pick up material. Although versatile these machines are not often used for day to day landfill operations, but are very useful for development work on any landfill.
The 'dozer blade gives a better finish to the landfill surface but the use of a bucket is more versatile.
The steel wheeled vehicle (compactor) is a machine specifically designed for landfill use and ruggedized designs more suited to the constant dust and short track stressing movements so common for compaction. These are now commonplace and this the comparative newcomer to the range of machinery available for controlled landfill operations, has become a core plant requirement for all landfill operators.
RESOURCE MANAGEMENT NEWSLETTER
The Selection and method of employment of Landfill Site Mobile Operational Plant is an important topic for any landfill operator and getting this right can provide a boost to the bottom line profitability of a site while by ensuring good high density emplaced waste with good compaction giving reduced settlement and minimal potential instability problems for the final landfill shape.