Sustainable Agro-Food Industrial Wastewater Treatment Using High Rate Anaerobic Process

This review article compiles the various advances made since 2008 in sustainable high-rate anaerobic technologies with emphasis on their performance enhancement when treating agro-food industrial wastewater. The review explores the generation and characteristics of different agro-food industrial wastewaters; the need for and the performance of high rate anaerobic reactors, such as an upflow anaerobic fixed bed reactor, an upflow anaerobic sludge blanket (UASB) reactor, hybrid systems etc.; operational challenges, mass transfer considerations, energy production estimation, toxicity, modeling, technology assessment and recommendations for successful operation

Sustainable Agro-Food Industrial Wastewater Treatment Using High Rate Anaerobic Process

This review article compiles the various advances made since 2008 in sustainable high-rate anaerobic technologies with emphasis on their performance enhancement when treating agro-food industrial wastewater. The review explores the generation and characteristics of different agro-food industrial wastewaters; the need for and the performance of high rate anaerobic reactors, such as an upflow anaerobic fixed bed reactor, an upflow anaerobic sludge blanket (UASB) reactor, hybrid systems etc.; operational challenges, mass transfer considerations, energy production estimation, toxicity, modeling, technology assessment and recommendations for successful operation

Sustainable Agro-Food Industrial Wastewater Treatment Using High Rate Anaerobic Process

This review article compiles the various advances made since 2008 in sustainable high-rate anaerobic technologies with emphasis on their performance enhancement when treating agro-food industrial wastewater. The review explores the generation and characteristics of different agro-food industrial wastewaters; the need for and the performance of high rate anaerobic reactors, such as an upflow anaerobic fixed bed reactor, an upflow anaerobic sludge blanket (UASB) reactor, hybrid systems etc.; operational challenges, mass transfer considerations, energy production estimation, toxicity, modeling, technology assessment and recommendations for successful operation

Highly sustainable cascade pretreatment of low-pressure steam heating and organic acid on pineapple waste biomass for efficient delignification

Cascade pretreatment of low-pressure steam heating (LPSH) and maleic acid (MA) on pineapple waste (PW) biomass aims to improve delignification, increase enzyme accessibility to carbohydrate in the feedstock while reducing inhibitor by-products. The best conditions for LPSH pretreatment were determined using one-factor-at-a-time (OFAT) while the conditions of MA pretreatment (temperature, acid concentration and time) were optimized by Box-Behnken design. A total of 68% (w/w) delignification with 79.5% (w/w) hemicellulose removal were achieved while 77.6% (w/w) cellulose was retained in the solid residue after the cascade pretreatment. No 5-hydroxylmethyl furfural (5-HMF) and acceptable furfural (1.8 g/L) were detected in the hydrolysate by high performance liquid chromatography analysis, with negligible amount of phenolic compounds (0.01 g/L). Compared to the pretreatment with combined LPSH and conventional sulphuric acid pretreatment (H2SO4), the pretreated PW produced 3.6 g/L of furfural and 0.4 g/L of HMF at similar optimized conditions. The pretreated PW were further characterized by scanning electron microscopy and Fourier transform infrared spectroscopy to analyze structural morphology and functional group changes. The pooled solid and liquid hydrolysate fractions generated from the LPSH and MA cascade pretreatment and subsequent enzyme hydrolysis has successfully generated 356.32 mg/g glucose and 156.91 mg/g xylose. The optimized cascade pretreatments provide up to 54.79% of glucose yield and 69.23% of xylose yield. Furthermore, 67.87% reduction of lignin content from the cascade pretreatment can substantially enhance the glucose yield up to 95.76% and xylose yield up to 99.07% during enzymatic hydrolysis using the mixture of cellulase and hemicellulase

Microbial biotechnology approaches for conversion of pineapple waste in to emerging source of healthy food for sustainable environment

One of the most significant and difficult jobs in food sustainability, is to make use of waste in the vegetable and fruit processing sectors. The discarded fruits along with their waste materials, is anticipated to have potential use for further industrial purposes via extraction of functional ingredients, extraction of bioactive components, fermentation. As a result of its abundant availability, simplicity and safe handling, and biodegradability, pineapple waste is now the subject of extensive research. It is regarded as a resource for economic development. This vast agro-industrial waste is being investigated as a low-cost raw material to produce a variety of high-value-added goods. Researchers have concentrated on the exploitation of pineapple waste, particularly for the extraction of prebiotic oligosaccharides as well as bromelain enzyme, and as a low-cost source of fibre, biogas, organic acids, phenolic antioxidants, and ethanol. Thus, this review emphasizes on pineapple waste valorisation approaches, extraction of bioactive and functional ingredients together with the advantages of pineapple waste to be used in many areas. From the socioeconomic perspective, pineapple waste can be a new raw material source to the industries and may potentially replace the current expensive and non-renewable sources. This review summarizes various approaches used for pineapple waste processing along with several important value-added products gained which could contribute towards healthy food and a sustainable environment

Sustainable Agro-Food Industrial Wastewater Treatment Using High Rate Anaerobic Process

This review article compiles the various advances made since 2008 in sustainable high-rate anaerobic technologies with emphasis on their performance enhancement when treating agro-food industrial wastewater. The review explores the generation and characteristics of different agro-food industrial wastewaters; the need for and the performance of high rate anaerobic reactors, such as an upflow anaerobic fixed bed reactor, an upflow anaerobic sludge blanket (UASB) reactor, hybrid systems etc.; operational challenges, mass transfer considerations, energy production estimation, toxicity, modeling, technology assessment and recommendations for successful operatio

A critical review of the transformation of biomass into commodity chemicals: Prominence of pretreatments

Biomass production has been increasing steeply with rise in population across the globe. Majority of the produced biomass has been un-utilized and thrown to landfill or discarded without proper disposal. Due to production of greenhouse gasses, possible land, and groundwater contamination due to presence of trace organic contaminants (TrOCs), various countries across the globe have implemented stringent regulations or even banned landfill for waste deposition. On the other hand, depletion in available resources and ever-increasing product demand, utilization of waste to recover value added products has been need of the hour across the globe. Biomass, a low-cost and abundant nutrient resource having a tremendous potential for replacement for fossil fuels dependence. Pre-treatments like physical, chemical, and biological were applied on biomass for product specific application recovery. However, commercialization of recovered value-added products by utilizing biomass is still far from being achieved because of social unacceptability (i.e., public acceptance) due to the presence of contaminants. So, this review discusses about utilization of various pre-treatments for recovery of commodity chemicals from biomass and it addresses how the presence of TrOCs in biomass influences the recovery of products during their conversion

Combined anaerobic and activated sludge anoxic/oxic treatment for piggery wastewater

International audienceIntensification of pig production in Brittany (France) led to high quantity of manure to be managed. In this context, a process combining anaerobic digestion and anoxic/oxic treatment was developed. The aim was to partially convert organic matter (OM) into a valuable energy, at the same time respecting the environmental constraints as regards nitrogen and reducing the energy costs at the farm scale. However, OM content of digested pig slurry is insufficient to allow a further complete denitrification of the mineral nitrogen content. Hence, three configurations were developed to manage the OM requirement and achieve denitrification such that (i) a fraction of the raw wastewater bypasses the digester and feed directly the anoxic/oxic reactor (Phase1), (ii) in addition to bypass, a recirculation was done from oxic reactor to digester (Phase 2 and 3), (iii) neither bypass nor recirculation (Phase 4). Partial nitrification (PN) was applied by regulating oxygen inflow time in Phase 3 and 4. Thus, the combined process allowed a removal of about 38-52% of CODt, 79-88% of CODs, 66-75% of TKN and 98-99% of NH4 +N concentrations. Anaerobic digester was able to produce 5.9 Nm3 of CH4/m3 of slurry added. Due to PN, the oxygen and OM requirements respectively for nitrification and denitrification were reduced. Comparison between each configuration was intrinsically difficult to make due to the difference observed in the slurry characterisation in each phase. However, a raw influent bypass between 20-30% combined with PN is suggested for piggery wastewater treatment in France, as the interest of recirculation from oxic reactor to digester is very limited using a CSTR

Processing High-Solid and High-Ammonia Rich Manures in a Two-Stage (Liquid-Solid) Low-Temperature Anaerobic Digestion Process: Start-Up and Operating Strategies

Globally, livestock and poultry production leads to total emissions of 7.1 Gigatonnes of CO2-equiv per year, representing 14.5% of all anthropogenic greenhouse gas emissions. Anaerobic digestion (AD) is one of the sustainable approaches to generate methane (CH4) from manure, but the risk of ammonia inhibition in high-solids AD can limit the process. Our objective was to develop a two-stage (liquid–solid) AD biotechnology, treating chicken (CM) + dairy cow (DM) manure mixtures at 20 °C using adapted liquid inoculum that could make livestock farming more sustainable. The effect of organic loading rates (OLR), cycle length, and the mode of operation (particularly liquid inoculum recirculation-percolation mode) was evaluated in a two-stage closed-loop system. After the inoculum adaptation phase, aforementioned two-stage batch-mode AD operation was conducted for the co-digestion of CM + DM (Total Solids (TS): 48–51% and Total Kjeldahl Nitrogen (TKN): 13.5 g/L) at an OLR of 3.7–4.7 gVS/L.d. Two cycles of different cycle lengths (112-d and 78-d for cycles 1 and 2, respectively) were operated with a CM:DM mix ratio of 1:1 (w/w) based on a fresh weight basis. Specific methane yield (SMY) of 0.35 ± 0.11 L CH4g/VSfed was obtained with a CH4 concentration of above 60% for both the cycles and Soluble Chemical Oxygen Demand (CODs) and volatile solid (VS) reductions up to 85% and 60%, respectively. For a comparison purpose, a similar batch-mode operation was conducted for mono-digestion of CM (TS: 65–73% and TKN: 21–23 g/L), which resulted in a SMY of 0.52 ± 0.13 L CH4g/VSfed. In terms of efficiency towards methane-rich biogas production and ammonia inhibitions, CM + DM co-digestion showed comparatively better quality methane and generated lower free ammonia than CM mono-digestion. Further study is underway to optimize the operating parameters for the co-digestion process and to overcome inhibitions and high energy demand, especially for cold countries