{'fraction_non_alphanumeric': 0.01606425702811245, 'fraction_numerical': 0.01606425702811245, 'mean_word_length': 4.370689655172414, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Biofiltration of WWTP sludge composting emission at contact times of 2 to 8 seconds

The performance of a biotrickling filter for the abatement of composting emissions was 
evaluated at short contact times of 2 to 8 seconds. The effect of EBRT, pH control and 
water renovation rate were evaluated. The average elimination capacity was 13 and 3.3 
g N/C m-3 
h 
-1 
 for ammonia and VOCs, respectively, and the maximum EC obtained 
during a doping process were 40 and 20 g N/C m 
-3 
h 
-1 
. Biotrickling filters appear as a 
better alternative than biofilters due to their controllability. However, water renovation 
becomes a critical parameter to avoid substrate inhibition by nitrite and ammonia 
accumulation. Not only ammonia absorption is negatively affected at low renovation 
rate but it is also affected the biological process. A decrease of 40 % was detected in the 
nitrification step when the hydraulic residence time increased from 2 to 5 hours. Results 
presented herein demonstrate that high removal efficiencies can be achieved for 
composting emissions in a biotrickling filter operated at short contact times which 
entails a substantial reduction of operational and investment costs in comparison to 
traditional techniques.