Recovery of Household Waste by Generation of Biogas as Energy and Compost as Bio-Fertilizer—A Review

Abstract

Nowadays, organic waste and especially household waste represents a significant global issue due to population growth. The anaerobic digestion (AD) process is an essential operation contributing powerfully to the valorization of organic waste including food waste in terms of renewable energy generation (biogas) and the rich-nutrient residue that can be utilized as bio-fertilizer. Thus, this process (AD) allows for good recovery of household waste by generating biogas and compost. However, the AD operation has been affected by several key factors. In this paper, we aim to involve different critical parameters influencing the AD process, including temperature, pH, organic loading rate (OLR), carbon to nitrogen ratio (C/N), and total solid content (TS(%)). Further, the paper highlights the inhibition caused by the excessive accumulation of volatile fatty acids (VFAs) and ammoniac, which exhibits the positive effects of co-digestion, pretreatment methods, and mixing techniques for maintaining process stability and enhancing biogas production. We analyze some current mathematical models explored in the literature, such as distinct generic, non-structural, combined, and kinetic first-order models. Finally, the study discusses challenges, provides some possible solutions, and a future perspective that promises to be a highly useful resource for researchers working in the field of household waste recovery for the generation of biogas.

Assessment ofAegle marmelosFruit Extracts as Organic Insecticide forSpodoptera exiguaonAllium ascolanicum

“…All organic waste -agricultural waste, livestock waste, kitchen waste, leftover food, and human excrement from pit latrines and septic tanks [50][51][52][53][54][55] can return to A. ascolanicum plantations to maintain and increase soil fertility. With anaerobic processing in individual or communal biogas digesters [56][57][58], a double benefit will be obtained, i.e., biogas -clean and renewable energy, and two types of organic fertilizers, i.e., solid and liquid fertilizers which are beneficial for agricultural crops [59][60][61][62]. Based on an environmentally friendly, this organic fertilizer should be combined with a biological fertilizer -Plant Growth Promoting Rhizobacteria (63)(64)(65)(66)(67).…”

The Control Strategy and Kinetics of VFAs Production in an ASBR Reactor Treating Low-Strength Mariculture Wastewater

“…The acetogenic bacteria could further change macro-molecular VFAs (propionate and butyrate) to acetate under anaerobic condition. Acetate is a favorite substrate of methanogens [27,28]. The number of methanogens increased with the accumulation of acetate.…”

Biomass: A Versatile Resource for Biofuel, Industrial, and Environmental Solution

“…Fig. 6 Flow chart of anaerobic digestion [154] Anaerobic digestion results in the spontaneous production of biomethane which occurs in four stages. To begin the process of breaking down complex organic polymers, their component constituents, which include sugars, fatty acids, and amino acids, are first released.…”