Performance Evaluation of Mesophilic Anaerobic Digestion of Chicken Manure with Algal Digestate

Na Duan,Panagiotis Kougias,Yuanhui Zhang,Xia Ran,Ruirui Li,Cong Lin,Hongbin Liu

doi:10.3390/en11071829

Abstract

Dilution is considered to be a fast and easily applicable pretreatment for anaerobic digestion (AD) of chicken manure (CM), however, dilution with fresh water is uneconomical because of the water consumption. The present investigation was targeted at evaluating the feasibility and process performance of AD of CM diluted with algal digestate water (AW) for methane production to replace tap water (TW). Moreover, the kinetics parameters and mass flow of the AD process were also comparatively analyzed. The highest methane production of diluted CM (104.39 mL/g volatile solid (VS)) was achieved with AW under a substrate concentration of 8% total solid (TS). The result was markedly higher in comparison with the group with TW (79.54–93.82 mL/gVS). Apart from the methane production, considering its energy and resource saving, nearly 20% of TW replaced by AW, it was promising substitution to use AW for TW to dilute CM. However, the process was susceptible to substrate concentration, inoculum, as well as total ammonia and free ammonia concentration.

Highlights

Livestock manure without appropriate management can cause serious problems to the environment, such as odor, attraction of insects, rodents, and other pests, release of animal pathogens, as well as surface and groundwater pollution [1]
The maximal methane production (104.39 mL/gVS) of diluted chicken manure (CM) was obtained with algal digestate water (AW) at total solid (TS) of 8% (Figure 1), which was 11.27% higher than that of the best performed tap water (TW) group at TS
79.79% was achieved by the diluted with AW of Results that the SCODremoval removal decreased with the increasing substrate concentration

Summary

Introduction

Livestock manure without appropriate management can cause serious problems to the environment, such as odor, attraction of insects, rodents, and other pests, release of animal pathogens, as well as surface and groundwater pollution [1]. Anaerobic digestion (AD) is considered to be an attractive and efficient technology for livestock manure treatment, apart from the main target of organic matter removal and environment pollution control, simultaneously producing biogas for local energy needs [2]. AD technology in livestock manure treatment for biogas production is very mature and considerable research has been intensively conducted [6,7], limited studies can be found on the AD of CM, especially mono-digestion [4,8]. The AD of original CM with a low carbon to nitrogen (C/N) ratio of 5–10 usually ends up with reactor instability, and even failure, due to its Energies 2018, 11, 1829; doi:10.3390/en11071829 www.mdpi.com/journal/energies

Methods

Results

Conclusion