Landfill leachate can broadly be defined as the liquid produced from the decomposition of waste and infiltration of rainwater, moisture, snow or other liquids in a landfill. This leachate is a
high-strength wastewater that has a major impact and influence on landfill design and its operation. It usually contains:
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high concentrations of ammonia and organic contaminants
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halogenated hydrocarbons
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heavy metals
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nitrogen compounds
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high concentrations of inorganic salts (mainly sodium chloride, carbonate and sulphate)
Therefore, there is a need to develop reliable and sustainable options to manage leachate generation and treatment effectively over a longer period of time.
STAGE 1: PRE-TREATMENT
THE RAW LEACHATE WATER:
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is pumped from the external buffer tank through a coarse filter into the feed tank
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will be conditioned to a pH-value of 6,0 - 6,5 to avoid precipitation
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is pumped by a low-pressure pump (pre-pressure pump) continuously through a sand filter and cartridge filter system
STAGE 2: REVERSE OSMOSIS STAGE 1 WITH CIRCULAR DISC MEMBRANES
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in the first stage (RO1) the organic and/or mineral contaminated raw water of the landfill will be treated
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the design of the equipment is based on the maximum concentration values of the waste water
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this stage is operating at a maximum operation pressure of 65 bars and is equipped with circular disc membranes
STAGE 3: REVERSE OSMOSIS STAGE 2
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the permeate of the RO1 will be polished in an additional membrane stage
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this stage works at an operation pressure of about 40 bars and is equipped with spiral wound membranes