Synthesis, Characterization, and Performance Evaluation of Hybrid Waste Sludge Biochar for COD and Color Removal from Agro-Industrial Effluent

Abstract

Agro-waste management processes are evolving through the development of novel experimental approaches to understand the mechanisms in reducing their pollution levels efficiently and economically from industrial effluents. Agro-industrial effluent (AIE) from biorefineries that contain high concentrations of COD and color are discharged into the ecosystem. Thus, the AIE from these biorefineries requires treatment prior to discharge. Therefore, the effectiveness of a continuous flow bioreactor system (CFBS) in the treatment of AIE using hybrid waste sludge biochar (HWSB) was investigated. The use of a bioreactor with hydraulic retention time (HRT) of 1–3 days and AIE concentrations of 10–50% was used in experiments based on a statistical design. AIE concentration and HRT were optimized using response surface methodology (RSM) as the process variables. The performance of CFBS was analyzed in terms of COD and color removal. Findings indicated 76.52% and 66.97% reduction in COD and color, respectively. During biokinetic studies, the modified Stover models were found to be perfectly suited for the observed measurements with R2 values 0.9741 attained for COD. Maximum contaminants elimination was attained at 30% AIE and 2-day HRT. Thus, this study proves that the HWSB made from biomass waste can potentially help preserve nonrenewable resources and promote zero-waste attainment and principles of circular economy.

Waste Derived Biocomposite for Simultaneous Biosorption of Organic Matter and Nutrients from Green Straw Biorefinery Effluent in Continuous Mode Activated Sludge Systems

“…This has an impact on the typical absorption peaks. Higher activation temperatures led to the disappearance of the absorption bands, particularly those around 3420-1640 cm −1 [37]. At 1432.64 cm −1 , the water-related absorption peaks associated with the bending vibration of the OH and NH groups of the hydrated reaction products can be seen.…”

Application of Artificial Neural Network for predicting biomass growth during domestic wastewater treatment through a biological process

“…The maximum measured COD concentration was 313 mg/L, which indicates high organic concentration in wastewater. High organic matter will require advanced treatment technologies and extended aeration, which consume high levels of energy due to additional airflow supply required [ 37 , 38 ].…”

“…Figure 10A shows that biomass growth was highest at the 2‐h mark which suggests that the stationary and death phases took place between the 2‐ and 4‐h mark. This indicates that when high wastewater temperatures are utilized, 4‐h hydraulic retention time is not necessary since the nutrients are already depleted and microorganisms have already reached the stationary and death phases [ 37 , 38 ].…”

Polymer-Based Nano-Adsorbent for the Removal of Lead Ions: Kinetics Studies and Optimization by Response Surface Methodology

“…This indicates that for advantageous (favorable) adsorption, 0 < 𝑅 < 1, 𝑅 > 1 denotes unfavorable adsorption, 𝑅 = 1 denotes linear adsorption, and 𝑅 = 0 denotes irreversible adsorption. According to study estimates, 𝑅 varied between 0.062 and 0.068, indicating that the adsorption is advantageous [41][42][43][44][45][46][47][48]. This indicates that for advantageous (favorable) adsorption, 0 < R L < 1, R L > 1 denotes unfavorable adsorption, R L = 1 denotes linear adsorption, and R L = 0 denotes irreversible adsorption.…”