Control of accumulated volatile fatty acids by recycling nitrified effluent.

ABSTRACT:

Background

Volatile fatty acids (VFA) often accumulate in anaerobic digestion systems, decreasing pH levels and causing unstable operational performance and poor biogas production. The aim of this study is to improve anaerobic digestion efficiency by controlling/reducing the accumulation of VFAs in a continuous anaerobic digestion system.

Methods

NO₃ ^--N was added to the digester and its effects on VFAs were investigated. When the system reached an unstable condition with the accumulation of VFAs, the digester was fed at an organic loading rate of 6 kg COD (chemical oxygen demand)/m³∙d and 0.5Q of aeration tank effluent (1500 mg/L of NO₃ ^--N) was recirculated.

Results

With the addition of NO₃ ^-

SUBMITTER: Park JG 

PROVIDER: S-EPMC6148226 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature