**3.5 Anaerobic digestion residue management**

Environmental impact assessment of an anaerobic digestion plant (a biogas station) should take into consideration both the plant emissions and the digestate management. The first aspect mainly relates to flue gas and odour emissions. The exhaust gases from gas motors must fulfil emission limit values, which is not a problem when appropriate gas pretreatment

reactors self-heating. It is advisable to use regeneration (Fig. 12), even in mesophilic temperature ranges, to minimize this expenditure, which on annual basis can contribute to

10-20 % of all biogas production (Pöschl et al., 2010).

Fig. 12. Scheme of the heat regeneration from output to input flows.

Fig. 13. Injection of biogas into natural gas grid (Behrendt and Sieverding 2010)

Environmental impact assessment of an anaerobic digestion plant (a biogas station) should take into consideration both the plant emissions and the digestate management. The first aspect mainly relates to flue gas and odour emissions. The exhaust gases from gas motors must fulfil emission limit values, which is not a problem when appropriate gas pretreatment

**3.5 Anaerobic digestion residue management** 

(sulphide and ammonia removal) has been applied. Unpleasant odours mainly originate from storage, disintegration and internal transport of organic waste. These should be carried over in a closed system, equipped with an air collection system fitted with a biofilter or connected with the gas motor air supply.
