Effect of Pressure on the Removal of NH<sub>3</sub> from Hydrolyzed and Pre-Fermented Slaughterhouse Waste for Better Biomethanization

Slaughterhouse waste (SW) is potentially a good source of biomethane; however, its excessive ammonia content quickly causes inhibition of microbial processes. Our aim was therefore to remove ammonia from SW before putting it into a biogas reactor. Experimental 120 L pressure container was constructe...

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Bibliographic Details
Main Authors: Aleš Zver, Rajko Bernik, Rok Mihelič
Format: Article
Language:English
Published: MDPI AG 2019-05-01
Series:Energies
Subjects:
Online Access:https://www.mdpi.com/1996-1073/12/10/1868
Description
Summary:Slaughterhouse waste (SW) is potentially a good source of biomethane; however, its excessive ammonia content quickly causes inhibition of microbial processes. Our aim was therefore to remove ammonia from SW before putting it into a biogas reactor. Experimental 120 L pressure container was constructed to observe NH<sub>3</sub> removal from diluted slaughterhouse waste at constant air flow of 144 NL/min, temperature 130 &#176;C, and at different pressures: 300 kPa, 600 kPa, and 900 kPa. SW was first allowed to hydrolyze for 14 days at 38 &#176;C. The SW was diluted with water (DSW) to 8.4% dry matter (DM) and forcibly aerated for 334 min. From the DSW, 0.7%, 3.8%, and 9% of initial total N were removed at 300 kPa, 600 kPa, and 900 kPa, respectively. However, the C/N ratio changed only slightly, from the initial 4.38 to 3.17, which is not a promising result for biomethanization. Further research on the presented system with the addition of bases might be promising to remove more ammonia.
ISSN:1996-1073