Landfill Remediation
Why Remediate Old Landfills?
The main reasons and benefits behind landfill remediation are:
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To rehabilitate contaminated areas |
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To redevelop/rezone land areas |
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To create new landfill capacity of up to 60% |
The Challenges of Landfill Remediation
There are many challenges that environmental engineers face during landfill remediation. The following needs to be managed effectively:
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Difficult working conditions for personnel on site |
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High demands on segregation technologies to separate different material types, as well as coarse and fine fractions |
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The need for gas extraction, gas stabilisation and neutralisation |
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Dust abatement measures |
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IUT’s Landfill Remediation Solution
IUT offers a complete and comprehensive solution for landfill remediation which includes:
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Preliminary investigation of the landfill |
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Feasibility study and safety plan |
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Logistics, excavation and transportation |
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Landfill gas stabilisation and neutralisation |
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Opening of landfill and mining of landfill material |
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Separation of material and chemical characterisation |
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Treatment on site or off site and backfilling |
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Characterisation and treatment of contaminated ground water |
The landfill remediation process is carried out in four main stages:
STAGE 1: STABILISATION
The first stage of the landfill remediation process is to stabilise landfill gas. Using IUT’s patented SMELL WELL System, methane and other noxious and hazardous landfill gases are treated and neutralised. This unique and patented system of landfill gas treatment allows safe and unimpeded work on the landfill site.
Patented SMELL WELL System
Here is a brief description of the SMELL WELL System:
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Lances are driven into the landfill in a grid formation (100-150 m²) |
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By means of pipes the lances are connected to two bio-filter stations |
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Fresh air is sucked through one bio-filter and forced into the landfill |
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The mixture of landfill gas and air is extracted and fed through another bio-filter for purification |
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The direction of airflow is regularly reversed |
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After 4-10 days, the environment inside the aerated area changes from anaerobic to aerobic |
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Odours and methane emissions are now eliminated and neutralized and excavation works can begin safely |
STAGE 2: MINING
Once an aerated area is stabilised, mining of material occurs in 3 metre layers. Fleet logistics is the key to the moving of large volumes of materials to the sorting stations. Abatement measures are necessary to minimise dust formation and air pollution.
STAGE 3: SORTING
The next stage of landfill remediation is material sorting and separation. The separation of materials is based on the following principles:
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The careful handling and subsequent treatment of landfilled waste |
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The classification of materials according to its properties |
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The application of low cost and robust sorting technology |
STAGE 4: TREATMENT
The last stage of landfill remediation is the process and treatment of the sorted materials. The handling and treatment of these sorted material includes:
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Recycling and reuse of recyclables which includes ferrous and non ferrous metals, wood waste and glass |
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Incineration of toxic and hazardous waste like chemicals |
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Plastics are treated and converted into refuse derived fuel (RDF) |
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Inerts like rocks, stones and sand are graded and backfilled into the landfill |
