High Total Solids Research Articles

During the winter, the performance of a temperate-zone channel catfish biofloc technology production system

In an outdoor biofloc technology production system, channel catfish (Ictalurus punctuates) have been successfully produced. In the tropics, outdoor biofloc production systems are used all year, while channel catfish research was limited to the growth season and biofloc production tanks. Harvested and put to rest for the winter. If a biofloc production system is to be used outside, Farmers in temperate latitudes, then, throughout the winter, data gaps related to system and fish performance. This issue must be addressed. The purpose of this research was to fill up these data gaps for channel catfish culture. Low (153.3 mg/L) water from a recently finished biofloc production experiment for this research; high total suspended solids (790.0 mg/L) were maintained. Per water source, there are three 15.7-m3 tanks. For a 152-day period, each type was supplied (8 kg/m3) with market-size channel catfish from the same research. From November through April, you will be studying. During the experiment, mean chlorophyll a concentrations were comparable in both treatments. Treatments diverged after 55 days, and chlorophyll a concentration grew linearly. (P 0.001, R2 = 0.721) in the low solids treatment to a mean final concentration of 2251.7 mg/m3. Ammonia Spikes of ammonium chloride (1.25–1.5 mg TAN) were added three times throughout the experiment. Completely biotransformed, presumably via algal absorption and nitrification. Biotransformation rate of ammonia. In the high solids (P 0.001, R2 = 0.920) and low solids (P 0.001, R2 = 0.920), was directly linked to mean water temperature. Treatments with (P = 0.002, R2 = 0.761). In biofloc tanks, catfish survival was excellent (99.75%) throughout the winter. There were no significant differences between the treatments. There was no significant difference in net fish output between the two groups. Treatments. Net fish yields, on the other hand, were 1–4% lower than starting fish biomasses. In the biofloc, there is water. Regardless of the weather, production tanks seemed to maintain their capacity to biotransform ammonia throughout the winter. Regardless of whether phytoplankton or suspended solids predominate, and despite ongoing ammonia nitrogen addition, having a functioning biofloc in the spring eliminates the need for a lengthy start-up period when establishing a new biofloc. Biofloc is completely functioning, as are the TAN and nitrite spikes.

Methane gas production from a mixture of cow manure, chicken manure, cabbage waste, and liquid tofu waste using the anaerobic digestion method

Biomass is valuable alternative energy worldwide as a substitute for fossil fuels can be converted into various forms of usable energy such as heat, steam, electricity, biogas, and liquid transportation biofuels. Cabbage waste, tofu liquid waste, cow dung and chicken manure is dangerous for the surrounding environment, which produces CH4 gas and has quite high BOD and COD values. This liquid waste has an amount of COD, suspended solids, and a high total solids content. One solution to overcome this pollution is by processing the waste into biogas, especially methane gas. The material will be transformed into methane gas by fermentation through the anaerobic digestion method. Before converting into biogas, initial characterization will be carried out in total C content, total N, COD, and C/N ratio. Then, from the biogas produced, the maximum data obtained is in variable B4 (55% cow dung: 15% chicken manure: 15% cabbage waste: 15% liquid tofu waste) with a total amount of gas of 7140 ml. This shows that tofu liquid waste can increase the potential amount of biogas produced.

Evaluation of physicochemical properties and viability of starter culture of liquid cheese whey-based frozen yogurts supplemented with inulin

ABSTRACT: The study aimed to analyze the physicochemical properties and starter culture viability of frozen yogurts produced with liquid cheese whey (LCW) and inulin at different proportions (F0: 66% LCW and 0% inulin; F1: 65% LCW and 1% inulin; F2: 64% LCW and 2% inulin; F3: 62% LCW and 4% inulin). Results demonstrated that the frozen yogurt F3 presented higher total solids and carbohydrates levels. LCW and inulin contributed to the overrun increase (11.8-18.2%) but did not interfere significantly in the retardation of the melting rate and range in the samples’ hardness. Over the storage time, formulation F3 showed lower pH and higher titratable acidity. However, from the sixtieth day of storage, the formulations of frozen yogurts varied in the pH and titratable acidity profile associated with the decline in the viability of starter cultures. Even so, the inulin supplementation positively affected the strains’ viability during storage. Based on our data, the formulation F3 presented better nutritional value, physicochemical characteristics, and stability over the storage period.

Co-Digestion of Grape Marc and Cheese Whey at High Total Solids Holds Potential for Sustained Bioenergy Generation.

At the end of fermentation, wine contains approximately 20% (w/v) of solid material, known as grape marc (GM), produced at a yield of 2 t/ha. Cheese manufacture produces cheese whey (CW), which is over 80% of the processed milk, per unit volume. Both waste types represent an important fraction of the organic waste being disposed of by the wine and dairy industries. The objective of this study was to investigate the bioenergy potential through anaerobic codigestion of these waste streams. The best bioenergy profile was obtained from the digestion setups of mixing ratio 3/1 GM/CW (wet weight/wet weight). At this ratio, the inhibitory salinity of CW was sufficiently diluted, resulting in 23.73% conversion of the organic material to methane. On average, 64 days of steady bioenergy productivity was achieved, reaching a maximum of 85 ± 0.4% CH4 purity with a maximum cumulative methane yield of 24.4 ± 0.11 L CH4 kg−1 VS. During the fermentation there was 18.63% CODt removal, 21.18% reduction of conductivity whilst salinity rose by 36.19%. It can be concluded that wine and dairy industries could utilise these waste streams for enhanced treatment and energy recovery, thereby developing a circular economy.

A multivariate snapshot of New Zealand milk seasonality in individual cows

Seasonal variation of milk composition poses a challenge for maintaining dairy product quality. Multivariate statistical techniques were used here to identify seasonal patterns in mineral levels, fatty acid profiles and selected metabolites for New Zealand raw milk collected from 24 individual cows in early-season (November), mid-season (January/February) and late-season (March). Partial least-squares discriminant analysis (PLS-DA) showed clear seasonal differences in mineral and fatty acid profiles that may have been related to supplementary feeding, dilution effects (higher total solids in late-season milk) and the lactation cycle. Fatty acid profiles showed an inverse relationship between the C6–C12 fatty acids and the branched- or long-chain fatty acids, which was thought to be related to feeding of maize in mid- and late-season. Targeted metabolite analysis suggested elevated phosphatase activity in March, and this warrants further investigation as an indicator of metabolic changes related to declining milk quality at the end of the milking season.

Effect of hydrogen peroxide on the microbial community present in biofloc production systems of the shrimp Litopenaeus vannamei

The biofloc technology (BFT) allows the production of aquatic organisms in high stocking densities with low effluent production. BFT is a system compounded of flocs highly colonized by aerobic heterotrophic and chemoautotrophic biota, which guarantee good water quality and represent a supplementary food source for the produced organisms. However, the large abundance of bacteria, protozoan, metazoan and raised organisms, may lead to a rapid consumption of dissolved oxygen in case of aeration systems malfunction or energy outbreaks. In BFT systems, one extreme alternative to keep oxygen in high levels is the addition of hydrogen peroxide (H2O2). However, H2O2 is a neutral molecule that can easily cross the cell membranes by diffusion, producing lipid and protein peroxidation and affecting the cells integrity. In a 10 days experiment, we have evaluated the effect of H2O2 on the microorganisms present in bioflocs during the production of the white shrimp Litopenaeus vannamei in a BFT system. Twelve 45-l containers with saltwater and mature bioflocs were stocked with 15 (5.51 ± 1.05 g) shrimp (333 shrimp m−3). Tanks were distributed into four treatments: control, with aeration and without application of H2O2, and the treatments 12 h, 24 h and 48 h with aeration suppression and the addition of hydrogen peroxide (10 μL H2O2 L−1) during these periods, whenever necessary to maintain dissolved oxygen levels above 6 mg L−1. The mean levels of dissolved oxygen were similar among treatments. Total suspended solids were significantly higher in the 12-h treatment. The addition of H2O2 did not affect the shrimp survival, but negatively influenced the nitrification process with the increment of ammonia and nitrite concentration. However, ammonia levels decreased few days after stopping H2O2 addition, whereas nitrite was still present in high concentration at the end of the experiment, indicating that ammonia-oxidizing bacteria recovered faster than nitrite-oxidizing bacteria. The Chlorophycea Planctonema sp. was mostly affected by hydrogen peroxide, with higher abundance in control than in 24 h and 48 h treatments. The abundance of these microalgae probably decreased due to light limitation caused by high total suspended solids in tanks. Protozoans, especially flagellates, were also negatively affected by the H2O2. Considering the results presented here, we must say that H2O2 should be used only in extreme cases, as an emergency tool.

Addition of a homeopathic, preventive product for mastitis in dairy cow feed: effects on etiologic agents, animal health, production, composition, and quality of milk

The aim of this study was to determine whether the addition of a homeopathic product to dairy cow feed would improve health and production efficiency, as well as composition and quality of milk. The product tested here was produced to stimulate immunity and indirectly to prevent the colonization of the mammary gland by bacteria, thereby decreasing somatic cell counts and bacteria in cow’s milk. Fifty dairy cows were used, divided into two groups: Control (n = 25) and Treated (n = 25). For 90 consecutive days, 50 grams of homeopathic product (treated group) was added to the concentrate; 50 g of the product vehicle (limestone) was added to the concentrate of the control cows. We performed composition and quality analysis on the milk (days 1, 15, 30, 45, 60, 75, and 90) as well as blood collection to carry out hematological and metabolism analyses (days 1, 30, 60, and 90). We found that fat content in the milk cows consuming the homeopathic agent was greater than that of the control group. Because of this increased fat content, there was a tendency towards higher total solids content in treated cows. A treatment effect was found in terms of total bacterial count (TBC); that is, there were lower TBCs in milk of treated animals than in control animals. There was a trend of a treatment effect versus day for somatic cell count (SCC); that is, there were lower SCC in animals that consumed the homeopathic on days 15 and 30 of the experiment. There was no difference between groups in terms of milk production; however, there was a negative correlation between milk production and TBC or SCC in the milk of cows that consumed homeopathic product. Animals in the treated group had lower total leukocyte and lymphocyte counts than did the control group, as well as a tendency toward lower neutrophil counts in these animals. Several bacteria were isolated from the cows' milk during the experimental period, with no treatment effect. In particular, we isolated Corynebacterium spp., Staphylococcus aureus, Staphylococcus epidermidis and Staphylococcus hyicus in greater numbers of cows compared to other etiologic agents. Based on these results, we conclude that consumption of the homeopathic product by dairy cows had positive effects on milk quality.

Changes and distributions of antibiotic resistance genes in liquid and solid fractions in mesophilic and thermophilic anaerobic digestion of dairy manure

This study mainly explored the changes and distributions of antibiotic resistance genes (ARGs) in liquid fraction (LF) and solid fraction (SF) in anaerobic digestion (AD) of dairy manure. After mesophilic and thermophilic AD, the copy numbers of ARGs in LF decreased by 0.06–1.80 logs while those in SF increased by 0.08–7.85 logs, suggesting the enrichment of ARGs in SF. Statistical analysis elucidated that high total solids promoted the enrichment of ARGs in SF. The increased abundances of genera such as Ruminofilibacter, Treponema and Sphaerochaeta in SF were responsible for the enrichment of most ARGs. These insights demonstrated the digested solid had the potential risks to promote the spread of ARGs in the environment, and the digested solid of livestock manure should be post-treated before the application.

Dry Anaerobic Digestion of Chicken Manure: A Review

Providing anaerobic digestion is a prospective technology for utilizing organic waste, however, for waste with a high content of nitrogen such as manure, dilution is necessary to decrease the ammonia inhibition effect which leads to the production of a huge effluent amount which is difficult to use. Dry anaerobic digestion has some advantages such as reduced reactor volume, higher volumetric methane yield, lower energy consumption for heating, less wastewater production, and lower logistic costs for fertilizers. These factors generate interest in using it for treatment of even high-nitrogen substrates. The purpose of this work was to analyze different dry anaerobic digestion technologies, the features of dry anaerobic digestion, laboratory studies on chicken manure dry anaerobic digestion, and methods of reducing inhibitors’ effects. Nowadays, there are no dry anaerobic industrial plants working on chicken manure. However, studies on dry anaerobic digestion of chicken manure have proven the possibility of methane production under fermentation of chicken manure with high total solids content, but the process has been described as being unstable. Co-fermentation, ammonium/ammonia removal, and adaptation of the microbial consortium have been used to decrease the effect of ammonia inhibition. A prospective way for ammonia concentration control is absorption using a non-volatile sorbent located in the reactor. It decreases ammonia content during wet anaerobic digestion by 33% and it is characterized by having a positive economic effect. Therefore, dry anaerobic fermentation of chicken manure is possible, but there is still no efficient way to provide it. The results of this article should be helpful in the selection of anaerobic digestion technology for treating chicken manure.

Peynir Altı Suyu Proteini Hidrolizatının Ayranda Yoğurt Starter Kültürleri ve Probiyotik Bakteriler Üzerine Etkilerinin İncelenmesi

This study aims to monitor the effect of whey protein hydrolysate (WPH) on the growth and activity of probiotic bacteria (Streptococcus thermophilus, Lactobacillus delbrueckii spp. bulgaricus, Lactobacillus acidophilus, and Bifidobacterium lactis) in ayran, and also to enhance the functionality of ayran by addition of the probiotics. Effects of WPH and probiotics addition as 0%, 0.25%, 0.5% and 1% on the growth of probiotic bacteria were studied before and after the fermentation and 7th, 14th, and 21st days of the storage. WPH and probiotics had a significant effect (p<0.05) on the growth of target microorganisms and the biochemical variables. The addition of WPH and probiotics significantly (p<0.05) increased the growth of probiotics compared to the control after the fermentation up to the 21st day of storage. The samples containing different WPH levels had lower (p<0.05) pH levels compared to the control during the study time. The mixing of WPH at 1% had the highest total solids and protein content compared to the control samples. The WPH decreased (p<0.05) the viscosity and Hunter color parameters in added the samples. Results indicated that WPH had great potential for enhancing the growth of probiotic bacteria and the nutritional of ayran.

Optimization of mixing in a Chinese dome digester for tropical regions

Optimization of mixing in a Chinese dome digester for tropical regions

Evaluating the Effectiveness of Adding Chicken Manure in the Anaerobic Mesophilic Codigestion of Sewage Sludge and Wine Distillery Wastewater: Kinetic Modeling and Economic Approach

Anaerobic digestion (AD) has been extensively investigated to obtain energy from chicken manure (CM). However, CM has high total and volatile solids (TS and VS) contents, making wet AD unsuitable f...

Metagenomic Study of Bacterial and Archaeal Populations during Anaerobic Digestion of Lignocellulosic Waste in Lab-scale Biogas Reactors

This study evaluated using 16S rDNA gene-based metagenomics technique the populations of bacteria and archaea in digestate samples from lab-scale anaerobic bioreactors digesting pretreated and untreated coconut husk fiber, pineapple floret and banana stem. Result of biodegradability experiment indicated high microbial activity in digestate (biogas slurry), with untreated banana stem having the highest total solids (TS) and volatile solids (VS) removal efficiencies of 78.3 % and 92.9 % respectively. Similarly, all pretreated substrates exhibited higher TS and VS losses with corresponding TS (77.8 %) and VS (87.2 %) removal efficiencies. This TS and VS removal rates signaled increased rate of organic matter decomposition with concomitant biogas productivity. Diversity comparisons performed between samples showed rich microbial diversity in untreated sample than the pretreated sample. Taxonomic composition revealed that, for untreated samples at the phylum level, the bacterial community was predominantly Firmicutes (relative abundance 97.0 %), with 0.30 % Actinobacteria and 0.10 % Proteobacteria. The genus Oxobacter (35.0 %), Clostridium (12.0 %) and Ethanoligenens (10.0 %) were ubiquitous and abundant in the untreated sample. The archaeal community was however dominated by the Euryarchaeota with one methanogenic order Methanomicrobiales, and a high abundance of the genera Thermacetogenium. For pretreated samples, at the phylum level, bacterial community was also dominated by Firmicutes (95.0 %), followed by Proteobacteria (1.02 %), Actinobacteria (0.18 %) and Tenericutes (0.06 %). The genus Clostridium (41.0 %), Ethanoligenens (29.0 %) and Lactobacillus (15.0 %) were also ubiquitous and abundant in the pretreated sample. Archaeal community was also dominated by Euryarchaeota with the two methanogenic orders Methanomicrobiales and Methanosarcinales dominating. The major microbial groups were hydrolyzing and fermenting populations. These findings revealed rich microbial assemblage and diversity among microbial communities in biogas digestate.

A holistic assessment of water quality condition and spatiotemporal patterns in impounded lakes along the eastern route of China's South-to-North water diversion project

Water quality is one of the key determinants for assessing effectiveness and success of water diversions, but rarely studied at a spatial scale that crosses large river basins. Multiple statistical methods and the water quality index (WQI) were used to assess overall condition and detect spatiotemporal patterns of water quality in a series of impounded lakes along the Eastern Route of China's South-to-North Water Diversion Project. Principal components analysis and analysis of variances identified three groups with distinct water quality characteristics: upstream Gaoyou Lake and Hongze Lake showing relatively higher nutrients, turbidity, and total suspended solids; downstream Dongping lake and Donghu Lake showing higher conductivity, total hardness, and chloride; and Luoma Lake and Nansi Lake intermediate between the two former groups. The WQI indicated overall “Good” water quality with an improving trend from upstream to downstream lakes. The upstream Gaoyou Lake had over 55% of the monitoring sites with “Moderate” water quality in all the seasons. Management should focus on preventing high nitrogen, phosphorus, turbidity, and total suspended solids in upstream lakes, high chloride in downstream lakes, high nitrogen during water diversion seasons, and high phosphorus during non-water diversion seasons. These findings greatly improved our understanding of the spatiotemporal water quality patterns of the impounded lakes, and can be used to develop water quality management strategies. This study exemplifies a methodology for investigating and securing water quality for inter-basin water transfer projects.

Infection dynamics of Theileria equi in carrier horses is associated with management and tick exposure

The tick-borne equine hemoparasite, Theileria equi, is endemic in many parts of the world where prevalence may be high, and most infected horses are apparently healthy but serve as life-long carriers. To determine the factors that affect T. equi dynamics, we followed parasitic loads in apparently healthy horses at four time points during one year. A total of 1094 blood samples were collected from 395 horses, along with ticks and demographic and clinical data. Infection and load of T. equi were tested by PCR and qPCR, and for the spring dataset, infection was also tested serologically by IFAT (n = 268). Theileria equi was molecularly detected in 64.8 % of the horses. The agreement between molecular and serological results was 79.8 % (K > 0.674) and positively correlated with parasitic load. Infection was associated with pale mucus membranes, lower packed cell volume and higher total solids (all P < 0.001), although these changes had only minor clinical importance. While parasitic loads in qPCR-positive samples (n = 561) were generally low (mean = 7.9−10−4% parasitized erythrocytes), younger horses showed higher loads, possibly suggesting development of immunity. Infection and parasitic load were associated with housing management and tick exposure, illustrating different patterns of exposure. Endemic stability is suggested in pasture farms with constant exposure to ticks, where parasite prevalence was high (96 %) and associated with T. equi 18S rRNA genotype D, low parasitemia and high antibody titers. Endemic instability can be suggested in case were horses are kept in paddocks (prevalence = 49 %) with intermittent exposure to ticks, where infection was associated with high parasitemia when ticks were present. A steady state is suggested in stabled horses (prevalence = 46 %), with no exposure to ticks; where infection was associated with genotype A, low parasitemia and low antibody titers. The ability to identify different risk groups within endemic areas may improve the administration of suitable treatment and control practices in an effort to reduce the risk of clinical disease.

Impact of total solids content on anaerobic co-digestion of pig manure and food waste: Insights into shifting of the methanogenic pathway

Dry anaerobic digestion (AD) has advantages over wet AD in treating high-solid organic wastes like livestock and food wastes, but an elevated total solids (TS) content would affect the AD performances. In this study, methane production of digesters co-digesting pig manure (PM) and food waste (FW) at different TS contents (R1, TS 5%; R2, TS 10%; R3, TS 15%; and R4, TS 20%) was assessed. The results showed the specific methane yield had no significant difference with the increase of TS contents from 5% to 15% (278.8–291.7 NmL/g VSadded), while it was reduced at a 20% TS content (259.8 NmL/g VSadded). Two peaks of total volatile fatty acids and daily methane production were observed in the high-solid digesters (R2-R4), while only one peak occurred in wet AD (R1). A new kinetics model was developed to describe the two-peak methane production behavior at high TS contents. The analysis on the microbial community structure clearly showed the different evolutions of methanogenic pathways in low and high solids content systems. In dry AD (R4), there was a general shifting from the acetoclastic pathway, to mixotrophic pathway and hydrogenotrophic pathway, with the dominance of mixotrophic and hydrogenotrophic methanogens.

Treatment of poultry slaughterhouse wastewater using tubular microfiltration membrane with fly ash as key precursor

Tubular membranes with fly ash as the primary precursor have been fabricated via extrusion process, which not only addresses the disposal issue of fly ash generated by thermal power plants but also aids in poultry slaughterhouse wastewater treatment. The fabricated membranes were characterized, and an optimum composition of 75% fly ash, 20% quartz and 5% calcium carbonate (Membrane K3) was fixed for the membranes to be used for separation processes. Membrane with the optimized composition has a pore size of 0.133 μm and porosity of 40.17% and offers outstanding chemical and mechanical stability. This membrane was further used for the treatment of poultry slaughterhouse wastewater, which is known to have high chemical oxygen demand (COD) and total suspended solids (TSS) content. The membrane successfully separated the organic matters present in the wastewater and the permeate water collected from the process satisfied the necessary environment protection norms regarding discharge and reusability. Hence, the inference can be drawn that the produced permeate water is completely reusable in poultry processing industries, which will help in mitigating the water scarcity problem prevailing nowadays.

Radical Aqueous Emulsion Copolymerization of Eugenol-Derived Monomers for Adhesive Applications.

Biobased monomers derived from eugenol were copolymerized by emulsion polymerization to produce latexes for adhesive applications. Stable latexes containing ethoxy dihydroeugenyl methacrylate and ethoxy eugenyl methacrylate with high total solids content of 50 wt % were obtained and characterized. Latexes synthesis was carried out using a semibatch process, and latexes with particle diameters in the range of 159-178 nm were successfully obtained. Glass transition temperature values of the resulting polymers ranged between -32 and -28 °C. Furthermore, tack and peel measurements confirmed the possibility to use these latexes in adhesive applications.

Soy ice cream as a carrier for efficient delivering of Lactobacillus casei

PurposeAmong soy products, soy ice cream with neutral pH, high total solids contents and prebiotic oligosaccharides is an appropriate vehicle for probiotics. The purpose of this paper is to survey soy ice cream as a carrier for the efficient delivering of Lactobacillus casei, or L. casei.Design/methodology/approachProbiotic soy ice cream containing L. casei was produced via the powder of soy milk. The physicochemical and organoleptic properties of the product were assessed. Also, the viability of L. casei was surveyed over a 180-day period of storage at −25 °C.FindingsThe density characteristic of probiotic soy ice cream demonstrated a significant rise (P < 0.05). The result of the viability analysis showed significant alterations in the number of probiotics in this product after freezing and throughout the 180-day period (P < 0.05). The most noticeable drop was seen throughout the first 60 days about 1.83 logs after that the trend of survival of this probiotic strain leveled off over the next 120 days. Also, no significant differences were found in the organoleptic properties of both ice creams.Originality/valueSoy ice cream with prebiotic elements protected the growing and activity of probiotic bacteria. The results showed that L. casei is a good probiotic for soy ice cream.

Up-flow vs downflow anaerobic digester reactor configurations for treatment of fats-oil-grease laden poultry slaughterhouse wastewater: a review

Abstract The process of anaerobic digestion has been and still remains the most efficient, cost effective and environmentally benign treatment process for poultry slaughterhouse wastewater (PSW). The PSW is characterized by a high concentration in chemical oxygen demand (COD), biological oxygen demand (BOD) and fats, oil including grease (FOG). The reactor configuration influences the performance of such anaerobic systems in the treatment of such oily wastewater. The up-flow reactor configuration provided by the Up-flow Anaerobic Sludge Blanket (UASB) Bioreactor or the Expanded Granular Sludge Bioreactor (EGSB) are highly dependent on up-flow velocity, which often contributes to periodical sludge washout during the treatment of PSW with high FOG and total suspended solids (TSS) concentration, resulting in poor reactor performance in comparison with downflow reactors such as the Static Granular Bed Reactor (SGBR), which achieves high organic load removal efficiency particularly when treating PSW due to its ability to retain sludge granules and solidified residue within the reactor. The washout of the sludge results from sludge flotation, which is induced by the inhibition of the anaerobic granular biomass by the accumulation of long chain fatty acids (LCFAs) from poor hydrolysis. The aim of this review is to highlight reactor configuration deficiencies, and to elaborate on the advantages of using anaerobic digestion for the treatment of FOG-laden PSW, with a focus on reactor performance. Additionally, a comparative analysis between up-flow reactors, such as the UASB including EGSB, and downflow reactors, such as SGBR, was performed.