(best examples and good practices) on household organic waste ...

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Heavy metals in digestate usually come from anthropogenic sources. Domestic
wastewater effluent contains metals from metabolic wastes, corrosion of water
pipes, <strong>and</strong> consumer products. Industrial effluents <strong>and</strong> waste sludge may
substantially contribute to metal loading. Agricultural wastes can contain
persistent organic contaminants such as (Pops) pesticide residues, antibiotics
<strong>and</strong> other medicaments. Industrial organic waste, sewage sludge <strong>and</strong> household
waste can contain aromatic, aliphatic <strong>and</strong> halogenated hydrocarbons, organchlorine
pesticides, PCBs, PAHs etc. (Al Seadi.,2003)
Biological Pollution
According to where they come from, a fact which differs from one region to
another <strong>and</strong> from time to time, organic wastes can contain various hazardous
matters, which can result in new routes of pathogen <strong>and</strong> disease transmission
to the whole feeding chain. Therefore, proper quality control of these types of
biomass must be done in relation with the biological treatment. The main
problems usually are related to:
(Al Seadi.,2003)
Pathogens
Seeds <strong>and</strong> Propagules
Transmissible Spongiform Encephalopathy (TSE
Physical Pollution
The digestate should be clean, in different circumstances, it could cause an
even more pollution, aesthetic damage to the environment, increase the AD
plants cost operation <strong>and</strong> affect operational stability of the plant, wear <strong>and</strong>
damage the plant components etc. The most frequent physical impurities are:
(Al Seadi.,2003)
Plastic <strong>and</strong> rubber
Metal
Glass <strong>and</strong> ceramic
S<strong>and</strong> <strong>and</strong> Stones
Cellulosic materials (wood, paper etc)
Other