TREATMENT OF LANDFILL LEACHATE

BASIC INFORMATION ABOUT LANDFILL LEACHATE

 

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:

  • high concentrations of ammonia and organic contaminants 
  • halogenated hydrocarbons
  • heavy metals
  • nitrogen compounds
  • 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.

Key requirements

  • Highest standards in technology
  • Highest environmental standards
  • Highest safety for the ecosystem
  • Highest safety for the population

reverse osmosis

  • the most efficient treatment of landfill leachate is Reverse Osmosis (RO) technology
  • advances in membrane technology have allowed the development of RO systems designed specifically for the treatment of leachate
  • the Reverse Osmosis (RO) technique aims to extract clean water from the aqueous solution of organic and inorganic contaminants that constitute the landfill leachate
  • the most efficient and best in class development is the circular disk membranes of Compentis, these modules have been specially developed for the treatment of highly contaminated waste water 

Stages of treatment

STAGE 1: PRE-TREATMENT

 

THE RAW LEACHATE WATER:

  • is pumped from the external buffer tank through a coarse filter into the feed tank
  • will be conditioned to a pH-value of 6,0 - 6,5 to avoid precipitation
  • 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

  • in the first stage (RO1) the organic and/or mineral contaminated raw water of the landfill will be treated
  • the design of the equipment is based on the maximum concentration values of the waste water
  • 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

  • the permeate of the RO1 will be polished in an additional membrane stage 
  • this stage works at an operation pressure of about 40 bars and is equipped with spiral wound membranes