Nowadays the cities are expanding so fast and the materials are being consumed, so the waste is being increasingly produced. So the right method of waste disposal is getting extremely critical. In recent years they’ve been developed two methods of waste disposal: pit-type and dump-type.
Pit type: In this method, one would seal the soil-bed with HDPE special coverage after almost 100 meters of excavation. Then one puts the drainage pipes and connects them to the shaft network.
The drainage system would collect the seepage from the waste and the leakage from the rain water and dispose them through the shafts.
Dump type: In this method, a region would be constrained with embankment (up to 20 m) and then it would be sealed with HDPE special coverage. Afterward the drainage systems are put there and then they’ll be connected to the manholes outside the region.
TNS can provide the requirement in this field with presenting the drainage pipes and shafts with great strength and chemical resistant to the various chemicals.
In principle at the dump type disposal only the drainage pipes are transferred into the waste object, the shafts are outside. Different to the pit disposal with waste heights of up to 100 m the dump usually reachs only a waste height of up to 20 m.
The TNS had as the first manufacturer worldwide an admittance for the drainage pipes of the DIBT (German Institute for construction technology in Berlin) and developed together with the LGA (Country Trade Institute in Nürnberg) calculation methods by the Finite Elemente Method. Today our drainage pipes are layed in almost all landfill sites of the Federal Republic Germany with waste cover heights of up to 100 m. The know-how of the TNS not only comprises the production of the PROFILEEN® drainage pipes and the static calculation but also the competent advice with regard to the optimize installation of the products.
The Finite Elemente Calculation method considers the kind of embedding of the pipes, so we recommend standard installations which are developed in years of research. The diameter of the drainage pipes is 300 mm. At first sight this seems to be oversized but the experience has shown that as a result of the aggressive chemicals in the seeping water there is the danger that the perforation of the pipes grows over with the years and that inside the pipes the chemical reaction produces foam which completely blocks smaller pipes.
At the PROFILEEN® drainage pipes the perforation and the pipe diameter are optimized so that a blockage can hardly happen and even if it should happen, the pipe can easily be cleaned again by a flush.
In principle, there are two kinds of landfills, the dump-type and the pit-type. In the pit the seeping water must be piped to the shafts which are also placed in the waste. The effects on the shafts which are caused by the settings in the waste of up to 40%, destroy every normal shaft construction. Therefore the TNS developed the so-called telescopic shaft about 20 years ago. Here the individual shaft elements are stored flexibly and can move with the waste object.
Usually the shafts have a diameter of 2000 mm or more because the maintenance must be carried out in the shafts. On the bottom of the shaft there are pumps for the transport of the seeping water as well as the entrances to the lechate pipes which have to be cleaned in regular distances. The telescopic shafts allow construction heights of up to 100 m in the waste object. The landfill site Mechernich at Cologne is a reference in this extremely difficult installation case.
Nowadays our PROFILEEN® telescopic shafts are found in all pit-type disposals of the Federal Repuplic Germany and with the adaption of the European norms and quality standards more and more neighbouring countries also consider this innnovative product by planning the landfill sites. Telescopic shafts can also be integrated into the existing dumps later so that the quality of old landfill sites can be improved considerably. Such projects were carried out by us on a large scale in England in the last few years.