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Dewatering is an important step in sludge treatment process; it reduces the quantity and valorize the quality of the produced sludge. This paper aims to discuss the use of screw press machine for dewatering sludge mixture from primary and secondary clarifiers in Jabal Asfar wastewater treatment plant (JAWWTP). The study was conducted using a pilot scale with capacity of 52 m3/h. Inlet and outlet samples were collected and transferred to the laboratory of JAWWTP for analysis. The speed of the screw press (rpm), the polymer dose (g) and the inlet TS% were monitored as operational parameters. Results showed that the screw press can dewater sewage sludge with lower total solids (TS) reached 0.5%. The optimum conditions for operating were regarded to the higher TS% in the outlet cake and the lower-energy and polymer consumption. Sewage sludge quantity entering the screw press fluctuated between 3.8 and 15.5 m3/h. Inlet TS ranged from 0.5% to 0.9% and the polymer consumption ranged from 2.7 to 18.6 g for each kg of dewatered sludge. Cost of dewatering processes ranged from US$ 0.009 to 0.064 for each kg of dewatered sludge depending on the polymer and energy consumption. TS outlet fluctuated between 13.12% and 21.6% depending on the TS inlet, the speed of the conveyer rotation and the polymer dose. The produced sludge will be dried and used for various purposes. It can be concluded that mechanical dewatering systems are suitable alternatives for conventional drying beds especially in highly populated cites, and screw press can dewater sludge with low TS content reached 0.5%. [ABSTRACT FROM AUTHOR]

Domestic biogas technology is a promising source of renewable energy for cooking in developing countries. It is popular in Nepal's rural and peri-urban areas and can be scaled-up to replace solid fuel cookstoves. This study focused on the technical assessment of installed biogas plants such as structural components, pipelines and valves, stove and burner, biogas production and utilization, and effluent disposal system in 303 homes in Kavre district, Nepal. Furthermore, it evaluated the feedstock material's physical and chemical parameters to ascertain their implications on biogas production. The plants' problems were mainly due to faulty components and lack of proper operation and maintenance. About 18% of plants were nonfunctional, out of which 9% of the plants were damaged due to the 2015 mega-earthquake. The highest number of damages was found in the mixture of the inlet structure. About 55% of mixtures were nonfunctional. Almost 77% of users used cow dung and toilet waste either individually or in combination with animal urine as feedstock materials in the digester. The Carbon: Nitrogen (C: N) ratio of feedstock materials ranged from 5:1–24:1, with only 4% of samples measuring C: N greater than 20:1. Similarly, pH (7.7) levels were on the higher side. • About 55% of mixtures and 30% of main valves were nonfunctional. • Above 80% users were not satisfied with the performance of biogas plants. • Faulty components and inadequate operation caused Inefficient plants' performance. • 18% of plants were nonfunctional, of which 9% were damaged due to 2015 mega-earthquake. • The C: N ratio of feedstock materials and pH were not in the desirable range. [ABSTRACT FROM AUTHOR]

This study performed bench scale studies on anaerobic co-digestion of cheese whey and septage mixed with biochar (BC) as additive at various dosages (0.5 g, 1 g, 2 g and 4 g) and total solids (TS) concentrations (5%, 7.5%, 10%,12.5% and 15%). The experimental results revealed 29.58% increase in methane yield (486 ± 11.32 mL/gVS) with 27% reduction in lag phase time at 10% TS concentration and 50 g/L of BC loading. The mechanistic investigations revealed that BC improved process stability by virtue of its robust buffering capacity and mitigated ammonia inhibition. Statistical analysis indicates BC dosage had a more pronounced effect (P < 0.0001) compared to the impact of TS concentrations. Additionally, the results were modelled using Gompertz model (GM) and artificial neural network (ANN) algorithm, which revealed the outperformance of ANN over GM with MSE 17.96, R2 value 0.9942 and error 0.27%. These findings validated the practicality of utilizing a high dosage of BC in semi-solid anaerobic digestion conditions. [Display omitted] • Biochar addition significantly enhanced methane generation by reducing lag phase time in anaerobic digestion of cheese whey. • Adding biochar improves methane generation, especially at low solids concentrations. • Gompertz model and artificial neural network (ANN) model were compared. • Optimal ANN model 2-9-1 attained MSE 18.96 and R2 value 0.9942. • Excellent fit of the Gompertz model with MSE of 24.10 and R2 of 0.9702. [ABSTRACT FROM AUTHOR]

Highlights • Sensory properties of cooked rice are important for consumer acceptance. • Autoclaving mainly affects stickiness of cooked rice, not hardness. • Sensory properties controlled by molecular structure of leached starch. • Molecular structure of leached starch is slightly affected by the cooking method. • Stickier texture of autoclaved rice from more amylopectin leaching during cooking. Abstract Autoclave cooking is used to produce "convenience" rice. In this study, autoclaving effects on sensory properties are investigated, and mechanistic explanations in terms of the underlying molecular structure are explored by analyzing this structure by size-exclusion chromatography and fitting the results with models based on biosynthetic processes. Compared to steam cooking, autoclaving produces stickier texture, and slightly affects hardness. It is found that molecular sizes of leached starch of both autoclaved and steam cooked rice are similar, but significantly smaller than that of the parent grain starch; model fitting parameters of leached amylopectin and amylose structures between autoclaved rice and steam cooked rice display no large variations. The amount of leached amylopectin (an important texture-controlling parameter) of autoclaved rice is higher than that of steam cooked rice. Correlation analysis indicates that, compared to steam-cooked rice, the stickier texture of autoclaved rice is caused by more amylopectin leaching during autoclaving. [ABSTRACT FROM AUTHOR]

Biochar can be used to improve the anaerobic digestion (AD) of agricultural wastes for higher methane production. However, the interaction of biochar addition with other factors of the anaerobic co-digestion (Co-AD) process has rarely been investigated. In this study, process models based on response surface methodology (RSM) and artificial neural network (ANN) were compared in modeling the methane yield (MY, mL CH 4 /g VS added) from the Co-AD of poultry litter and wheat straw with biochar addition. Box-Behnken design was applied, with the controlling parameters being carbon to nitrogen ratio (C/N), total solids (TS, %), and biochar addition (Biochar, % TS). Numerical optimization and genetic algorithm (GA) were used as optimization tools for RSM and ANN, respectively. A significant second-order quadratic model was built by RSM (R2 = 0.9981 and RMSE = 0.91), which demonstrated significant interactions between C/N and TS (p < 0.0001), and between C/N and Biochar (p < 0.05). The trained ANN (3−3−1) was less accurate (R2 = 0.9926, RMSE = 1.80) compared to RSM. The optimization results by RSM and ANN coupled with GA (ANN-GA) were both validated with prediction errors <0.5%. The optimization results by ANN-GA should be used since it generated a higher maximum MY of 290.7 ± 0.2 mL CH 4 /g VS added , under the optimal conditions of C/N ratio 24.46, TS 5.03%, and Biochar 8.73% TS, showing an improvement of 20.6% (compared to the control) through process optimization. The methods can also be applied in other scenarios for process modeling and optimization. The optimized results could support real applications of using additives including biochar, active carbon, nanoparticles, etc., to promote the bioenergy production from AD of agricultural wastes. [Display omitted] • Poultry litter and wheat straw were co-digested for bioenergy (methane) production. • Biochar-improved anaerobic co-digestion was modeled based on a Box-Behnken design. • Response surface methodology and artificial neural network (ANN) were compared. • RSM indicated a significant interaction between biochar addition and substrate carbon-to‑nitrogen ratio. • Optimal methane yield was determined by ANN coupled with genetic algorithm. [ABSTRACT FROM AUTHOR]

During high-solids anaerobic digestion (HS-AD) of the organic fraction of municipal solid waste (OFMSW), an important total solid (TS) removal occurs, leading to the modification of the reactor content mass/volume, in contrast to ‘wet’ anaerobic digestion (AD). Therefore, HS-AD mathematical simulations need to be approached differently than ‘wet’ AD simulations. This study aimed to develop a modelling tool based on the anaerobic digestion model 1 (ADM1) capable of simulating the TS and the reactor mass/volume dynamics in HS-AD of OFMSW. Four hypotheses were used, including the effects of apparent concentrations at high TS. The model simulated adequately HS-AD of OFMSW in batch and continuous mode, particularly the evolution of TS, reactor mass, ammonia and volatile fatty acids. By adequately simulating the reactor content mass/volume and the TS, the HS-AD model might bring further insight about potentially inhibitory mechanisms (i.e. NH 3 buildup and/or acidification) occurring in HS-AD of OFMSW. [ABSTRACT FROM AUTHOR]

This study evaluated the accumulated solids spatial distribution and their relationship with hydraulic conductivity ( K ) in a multi-cell horizontal subsurface flow (HSSF) constructed wetland (CW). The system is located near the Caribbean Coast of Colombia where tropical conditions reign. After three years of operation, total suspended solids (TSS) and volatile suspended solids (VSS) accumulated within the interstitial spaces and those that adhered to the surface of the gravel were quantified. Samples were collected at six points and at two depths (0.1 and 0.35 m) within each of five cells of the CW. Similar quantifications were made three months after a washing process of the granular bed. The average values for the first samples collected were 3.129 kg m −2 TSS and 35.5% VSS. The average values for the second samples collected were 0.224 kg m −2 TSS and 42.7% VSS. K values were measured after the gravel washing process using the falling head method. K values registered above 400 m d −1 , which coincided with the low amount of accumulated TSS (<1 kg m −2 ). This assessment revealed an inverse relation between accumulated solids and hydraulic conductivity (R 2 = 0.76), indicating that the accumulation rate of solids was the primary factor causing clogging within the constructed wetland treatment cells. In order to evaluate the state of clogging in tropical constructed wetlands, a dimensionless number was proposed as an indicator of clogging severity. [ABSTRACT FROM AUTHOR]

The volatile fatty acids (VFAs) concentration has been considered as one of the most sensitive process performance indicators in anaerobic digestion (AD) process. However, the accurate determination of VFAs concentration in AD processes normally requires advanced equipment and complex pretreatment procedures. A simplified method with fewer sample pretreatment procedures and improved accuracy is greatly needed, particularly for on-site application. This report outlines improvements to the Nordmann method, one of the most popular titrations used for VFA monitoring. The influence of ion and solid interfering subsystems in titrated samples on results accuracy was discussed. The total solid content in titrated samples was the main factor affecting accuracy in VFA monitoring. Moreover, a high linear correlation was established between the total solids contents and VFA measurement differences between the traditional Nordmann equation and gas chromatography (GC). Accordingly, a simplified titration method was developed and validated using a semi-continuous experiment of chicken manure anaerobic digestion with various organic loading rates. The good fitting of the results obtained by this method in comparison with GC results strongly supported the potential application of this method to VFA monitoring. [ABSTRACT FROM AUTHOR]

The development and utilization of bioenergy from various biomass can effectively reduce our dependence on fossil fuels and mitigate greenhouse gas emissions. The dry anaerobic digestion (AD) process is a promising technology for the treatment and stabilization of organic wastes (e.g., agricultural residues, livestock waste) with high total solid contents (15%–40%), while simultaneously recovering energy through biogas production (mainly methane). In the past few years, it has attracted significant attention because it possesses several advantages over wet AD, including higher volumetric methane yield, reduced digester size, less digested residue, and greater ease in handling the low-moisture digestate. This technology, however, still faces challenges owing to its excessive solids content. Additionally, dry AD is greatly different from wet AD in terms of technical operation, reactor design, and process performance. It is therefore essential to comprehensively understand dry AD and its characteristics, to analyze its operational factors, and to evaluate the optimization methods and techniques in order to develop practical applications. This paper presents a critical overview of the fundamental and engineering aspects of dry AD, and reviews specific characteristics of dry AD. Moreover, the operational conditions affecting the process stability of dry AD are discussed, as well as the strategies for improving its performance. Finally, challenges and prospects for its future application in treating high-solid organic waste are discussed. Future research on continuous/semi-continuous operations and scaling up of the lab-scale dry AD systems should be conducted. [Display omitted] • Dry AD is characterized by retarded mass transfer, high ammonia and high VFA concentrations. • High TS content has significant effects on methanogenesis pathway. • Co-digestion effectively reduces VFA accumulation and improves process stability. • Conductive materials promote microbial metabolic activity and biofilm formation. • Percolate recirculation improves mass transfer and speeds up biogas production. [ABSTRACT FROM AUTHOR]

Studying sludge rheology is an important factor for the management and disposal of produced sludge in a wastewater treatment plant. In this paper, the rheological characteristics of fresh and conditioned municipal sludge at different total solid contents (ranging from 1.8 to 3.7 g/l) were investigated. The selected conditioning agent was cationic polyacrylamide high molecular weight (CPAM-80). It was found that all samples behaved as shear thinning and limiting viscosity increased with increasing total solid concentration which followed Bingham model. In addition, settling index was increased by 50% with increasing solid content by 50%. The use of conditioning agent improved settling properties and the increased concentration of this agent reduced yield stress and limiting viscosity. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effects on feed intake, calf performance, feed efficiency, fecal score, passage rate, apparent nutrient digestibility, development of rumen and other organs, and body composition of increasing the total solids content of liquid feed (whole milk) by adding increasing amounts of milk replacer powder during the preweaning period. Crossbred Holstein-Gyr calves (n = 32) were assigned to 1 of 4 treatments (n = 8 per group), which consisted of different total solids concentrations: 12.5, 15.0, 17.5, and 20.0% of liquid feed. Calves received 6 L of liquid per day, divided into 2 equal meals (0800 and 1600 h) and provided in buckets, from 5 to 55 d of age. Starter and water were provided ad libitum during the entire experiment. At 56 d of age, animals were killed. Laboratory analysis determined that the actual total solids contents of the liquid feed were 13.5, 16.1, 18.2, and 20.4%, for the proposed 12.5, 15.0, 17.5, and 20.0% total solids treatments, respectively. The osmolality of liquid feed treatments was 265 to 533 mOsm/L. Fecal score was similar among treatments, except for wk 2 and 7. Intake of liquid feed was similar among treatments from 6 wk of age. During wk 4, 5, and 6, we detected a linear decrease in starter intake. After wk 7, we observed greater starter intake for calves fed approximately 16.1% total solids. Water intake, feed efficiency, and withers height were similar among treatments. Increasing concentrations of total solids in liquid feed quadratically affected average daily gain, final body weight, and empty body weight. We observed a greater average daily gain for calves fed approximately 20.4% total solids. Passage rate, nutrient digestibility, development of pre-stomachs and intestine, and body composition were similar among treatments. Increasing the concentration of total solids in liquid feed up to 20.4% reduced starter intake between 4 and 6 wk of life, but increased average daily gain. It did not affect passage rate, nutrient digestibility, ruminal and organ development, or body composition in calves during the preweaning period, indicating that this strategy may be a viable alternative for feeding without increasing the total volume of liquid feed provided to dairy calves. [ABSTRACT FROM AUTHOR]

Agricultural anthropogenic nitrogen (N) and phosphorus (P) continue to be major surface and subsurface water pollutants in developed countries. Integrated crop-livestock systems in the semi-arid Texas Rolling Plains are characterized by continuously cultivated monoculture combined with grazing. Improperly managed grazing can increase soil compaction, and subsequently, decrease infiltration, which leaves the soil exposed to erosion. Grazing is therefore of paramount importance to water quality. Cover crop (CC) use improves soil ecosystem services and functions. The objective of the current study was to characterize soil water quality following CC under continuous wheat (Triticum aestivum), grazing, tillage, and no-till practices under a typic Haplustepts, Rotan clay loam soil type. Treatments evaluated include 1) conventional tillage without a CC (CT); 2) no-till without a CC (NT); 3) no-till with a CC (NTC); and 4) no-till with a grazed CC (NTCG). Portable rainfall simulators were used to assess surface runoff water quantity and quality after CC implementation in a long-term no-till continuous wheat system. Cover crop treatments, both grazed and un-grazed, reduced the amount of runoff by 4–6 times compared to no CC treatments (NT and CT). Converting 12-year-old NT to CT reduced infiltration by at least 43 % and increased runoff by 58 % compared to long-term NT. Consequently, total solids load and concentration for CT were 4–14 times greater than all NT treatments (NT, NTC, NTCG). Conventional tillage (CT) also increased total P loads and concentrations by 2–11-fold compared to all NT treatments (p < 0.05). Rainfall events occurring within three weeks after CC termination resulted in about 6 times greater soluble reactive P (SRP) (except NTCG) and about 2–3 times greater dissolved organic C (DOC) concentrations from CC treatments than non-CC treatments, although this was not observed for subsequent runoff events. Tilling the soil had more deleterious effects compared to flash grazing CC. Adopting NT, either alone, or long-term in combination with CC (either flash grazed or un-grazed) are potentially sustainable viable practices in semiarid regions that can reduce environmental contamination. • Cover crops (CC) reduced runoff 4–6 times no CC treatments on Rotan clay loam soil. • CC increased dissolved organic carbon and soluble reactive phosphorus (SRP). • Grazing CC reduced SRP discharged into the environment compared to un-grazed CC. • Tillage reduced infiltration by 43 % and surged runoff by 58 % compared to no-till. • Flash grazing CC offers a chance for integrated crop-livestock systems resilience. [ABSTRACT FROM AUTHOR]

This study investigated the influence of soybean aging (cultivars Coodetec 214 and BRS 267) on the physicochemical properties of soymilk and tofu. Two aging conditions were adopted: accelerated aging (84% relative humidity and 30 °C, up to 9 months) and natural aging (ambient temperature and relative humidity, up to 18 months) and a control condition (47% relative humidity, −20 °C). Tofu was coagulated with MgSO 4 . Optimum coagulant concentration (OCC) decreased with increasing coagulation temperature and soybean aging time. OCC showed positive correlation with total solids, protein, ash, Ca, Mg and P contents of soymilk. The products showed, in general, reduced color parameters (L ∗ and h°), proteins, lipids, carbohydrates, ash, Ca, Mg, P and total solids (except in the tofu) and firmness (tofu) with increasing aging time. Tofu yields decreased with accelerated aging time. [ABSTRACT FROM AUTHOR]

[Display omitted] • First study exploring the effect of 3 key process parameters on the LD-DF of FVW. • Boosted H 2 production at pH 7, 5% total solids and 1.8 g VSS/L cell concentration. • H 2 production agreed with the lactate uptake and acetate and butyrate production. • Moderate H 2 yield (50 mL/g VS) but an outstanding rate (976.4 mL/L-h) was achieved. • Lactate-based DF is a promising route to transform FVW into H 2 at high rates. This study aims at investigating the influence of operational parameters on biohydrogen production from fruit-vegetable waste (FVW) via lactate-driven dark fermentation. Mesophilic batch fermentations were conducted at different pH (5.5, 6.0, 6.5, 7.0, and non-controlled), total solids (TS) contents (5, 7, and 9%) and initial cell biomass concentrations (18, 180, and 1800 mg VSS/L). Higher hydrogen yields and rates were attained with more neutral pH values and low TS concentrations, whereas higher biomass densities enabled higher production rates and avoided wide variations in hydrogen production. A marked lactate accumulation (still at neutral pH) in the fermentation broth was closely associated with hydrogen inhibition. In contrast, enhanced hydrogen productions matched with much lower lactate accumulations (even it was negligible in some fermentations) along with the acetate and butyrate co-production but not with carbohydrates removal. At pH 7, 5% TS, and 1800 mg VSS/L, 49.5 NmL-H 2 /g VS fed and 976.4 NmL-H 2 /L-h were attained. [ABSTRACT FROM AUTHOR]

As a fast growing plant, giant reed has good potential to be used as a feedstock for methane production via anaerobic digestion (AD). The effect of total solids (TS) content, an AD operating parameter, was studied. Results showed that increasing TS from 8% to 38% decreased methane yield, due to the inhibition of volatile fatty acids (VFAs) and total ammonia nitrogen (TAN); while the maximum volumetric methane production was obtained at 20–23% TS. Comparison of solid-state AD (SS-AD) at 20% TS and liquid AD (L-AD) at 8% TS was conducted at feedstock to effluent ( F/E ) ratios of 2.0, 3.5, and 5.0. The best performance was achieved at an F/E of 2.0, with methane yields of 129.7 and 150.8 L-CH 4 /kg-VS for SS-AD and L-AD, respectively. Overall organic components were degraded by 17.7–28.5% and 24.0–26.6% in SS-AD and L-AD, respectively; among which cellulose showed the highest degradation rate and the highest contribution to methane production. [ABSTRACT FROM AUTHOR]

Abstract: The hemodilution effect of manually preheparinized syringes was determined by evaluating the packed cell volume (PCV) and total solids (TS) from blood samples collected from 50 American alligators (Alligator mississippiensis). A volume of 0.2mL of blood was drawn into 3 syringes of 1mL: control with no heparin sodium, heparin sodium drawn to 0.1mL and then expelled, and heparin sodium drawn to 0.2mL and then expelled. PCV and TS values were determined from each syringe immediately after collection. Mean PCV and TS values were compared between the control and heparin groups using linear mixed modeling. The syringes coated with heparin resulted in a significantly lower mean PCV and TS values when compared with controls, with no significant difference between the heparin groups. This dilution effect was also found to be inconsistent and not accurate from one syringe to another. An adjunct method of obtaining 0.5mL from already-collected blood samples into 1-mL syringes that were coated with heparin drawn to 0.2mL and then expelled also showed a significant decrease in PCV and TS values when compared with the control samples, although to a lesser extent. As a result, it cannot be recommended to manually preheparinize syringes when collecting small volume of blood samples from American alligators because significant and unpredictable hemodilution is likely to occur. [Copyright &y& Elsevier]

Abstract: Anaerobic digestate have been identified as a rich source of essential plant nutrients. Nevertheless, its safety measured by the concentration of pathogen present is of great concern to end users. This research explored the efficiency of the mesophilic biodigestion process in the stabilization and sanitization of cow dung and chicken droppings. Six (6) kg each of cow dung and chicken droppings were collected fresh and free from impurities, pre-fermented, mixed with water in the ratio 1:1 w/v to form slurry, fed into the respective reactors and digested for 30 days at an average ambient temperature of 30 ± 2 °C. The pH of the medium fluctuated between 6.5 and 8.0. The analysis of the feedstock and effluent of the digesters showed that a total solids reduction of 75.3% and 60.1% were recorded for cow dung and chicken droppings while the reduction in total coliforms was 95% and 70% respectively for the dung and droppings. Microbial analysis of the biofertilizer produced reveals both aerobic and anaerobic organisms which include species of Pseudomonas, Klebsiella, Clostridium, Bacillus, Bacteroides, Salmonella, Penicillum and Aspergillus. Escherichia coli and Shigella spp. were removed while species of Salmonella and Klebsiella were still present in the digestate. Notwithstanding these results, the digestate still requires further treatment for it to be suitable for application on unrestricted crops either as fertilizer; otherwise a health problem would be created as attempt is made to improve soil fertility. [Copyright &y& Elsevier]

Abstract: Chitin is a natural copolymer found in crustacean shells and has potential for use in a wide range of faculties. During the chitin obtainment process, effluents with high organic charge are generated. These should be treated before discharge in order to avoid environmental problems. This work aimed to investigate the treatment of effluents from chitin obtainment process using chitin (CH) and aluminum sulfate (Al2(SO4)3) as coagulants. The effects of coagulant type (CH and Al2(SO4)3), coagulant concentration (150 and 300mgL−1) and pH (6.0 and 8.5) were evaluated by a full 23 experimental design. The considered responses were: total solids reduction (TSR), suspended solids reduction (SSR) and turbidity reduction (TR). It was found that the use of 300mgL−1 of Al2(SO4)3 under pH 6.0 or 8.5 favored the treatment of effluents from chitin obtainment process. The proposed treatment provided reductions of 20, 89 and 85% in the total solids, suspended solids and turbidity respectively. [Copyright &y& Elsevier]

Abstract: Organic fraction of municipal solid waste (OFMSW) was used to feed two pilot plants of 1000l working in anaerobic conditions. The OFMSW had previously been treated using a system of extrusion which, due to exerted pressure, separates the undesired fractions of waste from organic waste and reduces the organic fraction in a kind of homogeneous jam. Pilot tests were performed in semi-continuous conditions with a stepwise progressive increase of the total solids content (TS) of the input material from 3% TS w/w (1.5gVSl−1 d−1 organic loading rate) to 10% TS w/w (4.3gVSl−1 d−1 organic loading rate) using activated sludge as diluting agent. The average specific biogas production obtained was 600lkg−1 VS. When the input TS content was increased to 10% w/w, the biogas average specific production went up to 800lkg−1 VS. The methane content in the biogas was always higher than 60% measured by volume. [Copyright &y& Elsevier]

Abstract: Processing tomato is a high water demanding crop, thus requiring irrigation throughout growing season in arid and semiarid areas. The application of deficit irrigation (DI) strategies to this crop may greatly contribute to save irrigation water. A two-year study was carried out in order to assess the effects of DI upon water productivity, final biomass, fruit yield and some quality traits of open-field processing tomato cv. Brigade in a typical semi-arid Mediterranean environment of South Italy. Four irrigation treatments were studied: no irrigation following plant establishment (V0); 100% (V100) or 50% (V50) evapotranspiration (ETc) restoration up to fruit maturity, 100% ETc restoration up to flowering, then 50% ETc restoration (V100-50). Total dry biomass accumulation was significantly depressed by early soil water deficit in V0; irrigation at a reduced rate (50% ETc) from initial stages (V50) or from flowering onwards (V100-50) did not induce any losses in final dry biomass. The marketable yield did not significantly differ among plots irrigated, but an averaged irrigation water saving of 30.4% in V100-50 and 46.2% in V50 was allowed as compared to V100. Marketable yield was negatively affected by the early water shortage in V0, due to the high fruit losses (>44%). The effects of DI on fruit quality were generally the converse of those on fruit yield. DI improved total soluble solids content, titratable acidity and vitamin C content. Water use efficiency was positively affected by DI, suggesting that the crop does not benefits from the water when this last is supplied to fulfil total crop requirements for the whole season. Yield response factor, which indicates the level of tolerance of a crop to water stress, was 0.49 for total dry biomass (Kss) and 0.76 for marketable yield (Ky), indicating that in both cases the reduction in crop productivity is proportionally less than the relative ET deficit. In conclusion, the adoption of DI strategies where a 50% reduction of ETc restored is applied for the whole growing season or part of it could be suggested in processing tomato, to save water improving its use efficiency, minimizing fruit losses and maintaining high fruit quality levels. This aspect is quite important in semi-arid environments, where water scarcity is an increasing concern and water costs are continuously rising. [Copyright &y& Elsevier]

Abstract: In order to assess the effect of soil water deficit (SWD) during fruit development and ripening, on yield and quality of processing tomato under deficit irrigation in the Mediterranean climate, an open-field experiment was carried out in two sites differing from soil and climatic characteristics, in Sicily, South Italy. Six irrigation treatments were studied: no irrigation following plant establishment (NI); 100% (F=full) or 50% (D=deficit) ETc restoration with long-season irrigation (L) or short-season irrigation up to 1st fruit set (S); and long-season irrigation with 100% ETc restoration up to beginning of flowering, then 50% ETc restoration (LFD). The greatest effect of increasing SWD was the rise in fruit firmness, total solids and soluble solids (SS). A negative trend in response to increasing SWD was observed for fruit yield and size. Tough yield and SS were negatively correlated, the final SS yield under the LD regime was close to that of LF, and 47% water was saved. However, SS seems to be more environmental sensitive than SWD, since it varied more between sites than within site. The variations between sites in fruit quality response to deficit irrigation demonstrate that not only SWD but also soil and climatic characteristics influence the quality traits of the crop. [Copyright &y& Elsevier]

Abstract: Slurry samples, collected from 41 commercial swine farms in South Korea, were characterized in various physico-biochemical, macro and micronutrients, heavy metals and microbial parameters. Interestingly, significant variations were observed in all the parameters. However, positive relationships were noticed between EC and ammonia nitrogen (NH3-N), total nitrogen (TN), total potassium (TK), specific gravity (SG), total solids (TS), volatile solids (VS), fixed solids (FS), total dissolved solids (TDS) at R 2 =0.91, 0.74, 0.69, 0.60, 0.50, 0.48, 0.55, and 0.52, respectively. Whereas phosphorous and other nutrients shown poor correlation. Escherichia coli and Salmonella were counted at an average of 5.04 log10 colony forming unit (CFU)/mL and 3.55 log10 most probable number (MPN)/mL, respectively. Equations for predicting nutrients content in swine slurries are presented with EC, because it is an easily determinable parameter. The data obtained in this study could be used as a guideline for Good Management Practices in South Korean swine farms as well as other countries. [Copyright &y& Elsevier]

Abstract: The optimization of total solids in the feed (%TS) and alkalinity ratio (γ) for H2 production from organic solid wastes under thermophilic regime was carried out using response surface methodology based on a central composite design. The total solids levels were 20.9, 23.0, 28.0, 33.0 and 35.1% whereas the levels of alkalinity ratio (defined as g phosphate alkalinity/g dry substrate) were 0.15, 0.20, 0.30, 0.41 and 0.45. High levels of TS and γ affected in a negative way the H2 productivity and yield; both response variables significantly increased upon decreasing the TS content and alkalinity ratio. The highest H2 productivity and yield were 463.7NmL/kg-d and 54.8NmL/gVSrem, respectively, predicted at 20.9% TS and alkalinity ratio 0.25 (0.11gCaCO3/g dry substrate). The alkalinity requirements for hydrogenogenic processes were lower than those reported for methanogenic processes (0.11 vs. 0.30gCaCO3/gCOD). Adequate alkalinity ratio was necessary to maintain optimal biological activity for hydrogen production; however, excessive alkalinity negatively affected process performance probably due to an increase of osmotic pressure. Interestingly, reactor pH depended only on the alkalinity ratio, thus the buffer capacity was able to maintain a constant pH independently of TS levels. At γ =0.15–0.30 the pHs were in the range 5.56–5.95, which corresponded to the highest hydrogen productivities and yields. Finally, the highest metabolite accumulation corresponded with the highest removal efficiencies but not with high H2 productivities and yields. Therefore, it seems that organic matter removal was channeled toward solvent generation instead of hydrogen production at high TS and γ levels. This is the first study that shows the requirements of alkalinity in solid substrate fermentation conditions for H2 production processes and their interaction with the content of total solids in the feed. [Copyright &y& Elsevier]

Improving the treatment efficiency of sludge in Alexandria, Egypt, was studied to improve the primary and secondary sludge treatment efficiency, different doses ranging from 0.25 to 6 kGy of ionizing radiation were proposed and evaluated. The scope of This study is to assess the radiation-based treatment efficiency from physical, chemical, and biological perspectives and to compare between the conventional treatment method and the radiation-based treatment technology. To evaluate the performance of each treatment system, pH, oil and greases concentrations, total solid concentrations, BOD concentrations, COD concentrations, parasites, and microorganisms were assessed in the primary and secondary samples at different radiation doses (from 0.25 to 6 KGy), and in the conventionally treated samples. Irradiation by gamma radiation with a dose ranging from 0.25 to 6 kGy was efficient in reducing some of the physical contaminants. Oil & greases, Total Solids, BOD, COD concentrations were reduced significantly (p < 0.001) in a dose-dependent manner. Either primary or secondary sludge samples, total solid reduced significantly to about one-third of control concentration at six kGy. Six kGy able to reduce the BOD and COD concentrations in the primary sludge samples to that of the treated (after sludge dewatering) samples or less respectively and saved the secondary treatment stage. In primary and secondary sludge samples culture, E. coli , Staphylococcus aureus , and Vibrio spp were isolated as heavy growth on different culture media in the samples before radiation. After exposure to increasing doses of radiation, the number of isolated organisms decreased, however, the growth of Proteus, Acinetobacter, and vipro organisms was detected but in small numbers. No growth of any organism was noted at 5 kGy. On the other hand, in the secondary sludge samples, Proteus was isolated as heavy growth before radiation and After exposure to increasing doses of radiation, Moraxella spp. organisms were detected but in small numbers. By increasing the radiation doses, the free-living ciliates were decreased in the primary and secondary sludge samples. The free-living ciliates disappeared completely at 3 kGy. In the primary and secondary sludge samples, free-living ciliates reduction efficiency at 0.25 kGy was equivalent to the conventional treatment methods. So, we can conclude that radiation technology using Gamma rays at a dose higher than 5 kGy with a dose rate of 1.095 kGy/h is an effective technology for domestic and industrial waste sludge treatment from the environmental perspective and an experimental pilot plant study is required to optimize the cost of wastewater treatment through the use of irradiation technology. Recommendations: ❖ Either in primary or secondary sludge samples, the concentration of oil & greases reduced significantly (p < 0.001) in a dose dependent manner, that leads us to investigate later a higher radiation doses which might reduce the concentration of oil & greases to the level of the treated samples. ❖ An experimental pilot plant study is required to optimize the cost of wastewater treatment using irradiation technology. ❖ Study the other perspectives like economy and/or social. ❖ Study the effect of radiation on surfactants, nitrogen and phosphorus ingredients, heavy metal ions and other sludge components. [ABSTRACT FROM AUTHOR]

Abstract: Concern about pollution related problems in the global scenario are persuading all the processing industries to adopt cleaner manufacturing practices. Thus, the leather industry is also under pressure to look for effective alternative tanning materials for chromium. Natural products like vegetable tannins are regaining importance. However, there are limitations in the use of vegetable tanning materials because of its high organic load in the effluent, which are difficult to degrade leading to high chemical oxygen demand (COD). Moreover, conventional vegetable tanning process requires partial pickling that involves the use of sodium chloride, to suppress osmotic swelling. This results in very high amount of total dissolved solid (TDS) content in wastewaters. In this investigation, an attempt has been made to design an eco-friendly vegetable tanning process combining pickle-free tanning and application of proteolytic enzymes to improve the exhaustion of vegetable tannins. Such an approach has resulted in more than 95% tannin exhaustion in the case of the experimental process, an increase of 10% compared with the conventional vegetable tanning process. The tanned leathers showed slight improvement in hydrothermal stability. Physical and tactile evaluation of experimental leathers has been better than conventionally tanned leathers. Surface colour values illustrated negligible variation in colour and shade between control and experimental leathers. The resultant leather showed opened up, split compact fibre structure that has been well coated, indicating that the enzyme assisted tanning process did not bring about any major change or destruction on the fibre structure of the leathers. The optimized system has been field tested in a commercial tannery. The results showed that the enzyme assisted tanning process is efficient in terms of improved quality of leather and also led to reduction in total solids (TS), chlorides and COD loads. The enzyme assisted tanning system presented appears to be a viable option for combating pollution arising from the conventional vegetable tanning system. [Copyright &y& Elsevier]

Abstract: This study investigated firmness and syneresis of set yoghurts made at the CN to WP ratios of 4:1, 3:1, 2:1 and 1:1 using non-EPS-, capsular EPS- and ropy EPS-producing starter cultures. The yoghurts were made at 9 and 14%(w/w) total solids. The total solids, total protein, the concentration of lactose and the ratios of CN to WP as well as the protein''s profiles (native- polyacrylamide gel electrophoresis) in heated and unheated milk blends were investigated. The level of soluble denatured whey protein aggregates in heated milk was also determined. The concentration of EPS, firmness and level of spontaneous syneresis in set yoghurt were monitored weekly throughout 28 days of storage. The microstructure of the set yoghurt made with milk blends at the CN to WP ratio of 4:1 and using three types of starter cultures was carried out after 1 day of storage. There was no difference in the total solids, total protein and lactose concentration of liquid milk blends, except the CN to WP ratios. There was no difference in whey protein denaturation between milk blends. The level of soluble denatured whey protein aggregates in heated milk blends decreased with reducing CN to WP ratio. The firmness and the level of spontaneous syneresis in set yoghurts decreased as the CN to WP ratios were reduced. The use of EPS-producing starter cultures reduced firmness and syneresis and changed the protein matrix in the microstructure of set yoghurts made at 9%(w/w) total solids compared to the control products. These were not observed in set yoghurts made at 14%(w/w) total solids. [Copyright &y& Elsevier]

The aim of this study was to determine the effect of the ratio of sulfur added to total sediment solids (SA/TS) on the remobilization of heavy metals from contaminated river sediment by indigenous sulfur-oxidizing bacteria. Also, the difference in metal binding fractions before and after bioleaching was explored.It was found that sediment pH decreased at a significantly faster rate at higher SA/TS ratios (0.413 and 0.199) than at lower ones. Sulfate concentrations increased at a faster rate at these higher SA/TS ratios. At the lower SA/TS ratios, more acid must be produced and therefore it took more time for sulfur-oxidizing bacteria to lower the sediment pH. Remobilization efficiency of total extractable Pb and Cr was significantly higher at higher SA/TS ratios. After bioleaching, Mn-oxides became a stronger binding pool, and the percentage of Pb and Zn bound to Mn-oxides and Cr and Cu bound to organic matter increased with the decrease of SA/TS. Different heavy metals showed different binding behavior at the various SA/TS ratios. [Copyright &y& Elsevier]

A nondestructive optical method for determining the total solids content (TSC) and soluble solids content (SSC) of fresh whole prune (Prunus domestica L. ‘French’) was investigated. The method, based upon near infrared spectrophotometric techniques, could predict the TSC (r2=0. 98, SEP=0.80% FW) and SSC (r2=0. 96, SEP=1.02%) of prunes. A low cost ($2500 2002 USD) diode array-type spectrophotometer was used in the study. [Copyright &y& Elsevier]

Beam house processes1Beam house processes generally mean liming–reliming processes, which employ beam.1 in leather processing are known for their uncleanness. More than 60% of the total pollution is emerging from the liming–reliming processes. The use of lime and sodium sulphide is purely empirical without quantification. Lime has a potential to drive swelling in a gradual manner due to its low solubility; however, the use of lime is currently creating a lot of environmental concern. Huge amounts of lime sludge and total solids formation are the main drawbacks of lime. Sulphide plays a detrimental role in effluent treatment plants. This is mainly due to the application of lime, sulphide, water and other chemicals without any rationalization. An approach has been made to apply the beam-house chemicals with optimal requirement. This is based on the fact that swelling requires only 20 to 40% water (based on raw skin weight before soaking) for conventional opening up. This would, in principle, make possible the use of only one tenth of the chemicals conventionally used in liming–reliming processes maintaining the same concentration gradient. The process employs 40% water, 0.35% sodium sulphide and 1% lime for liming and 40% water and 1% lime for reliming, with conventional process time in a drum. Commercial post-reliming processes and operations were adopted. A control experiment was run parallel using conventional liming–reliming processes. It has been found that the dehairing is complete and the extent of opening up of fibre bundles is comparable to that of the control. This has been substantiated through scanning electron microscopic, stratigraphic chrome distribution analysis and softness measurements. Performance of the leathers is shown to be on par with conventionally opened up leathers through physical and hand evaluation. Especially, softness of the leathers is numerically proven to be comparable with that of control. The process also enjoys reduction in chemical oxygen demand and total solids load on environment by 85 and 12%, respectively compared to the conventional process. The total dry sludge from the liming–reliming processes is brought down from 152 to 6 kg for processing 1 ton of raw skins, which has been demonstrated for the first time. [Copyright &y& Elsevier]

Few studies have investigated the performance of anaerobic digestion (AD) to convert animal and agro-industrial wastes to organic fertilizers over a long-term field conditions. This paper studied three large-scale mesophilic digesters (D1–D3) over two years for their effects on feedstocks, which were dairy manure for D1 and D2 and co-digestion mixed manure and agro-industrial wastes for D3. Hydraulic retention times (HRT) were 9 d for D1, 12 d for D2, and 34 d for D3. Digester influent and effluent samples were taken every two months from the digesters and analyzed for pH, and concentrations of total solids (TS), ammonium nitrogen (NH 4 -N), total Kjeldahl nitrogen (TKN), total phosphorus (TP), and eight metals. The study revealed high variability in converting feedstock in the three digesters. Compared with their respective influent, the mean digester effluent pH decreased from 7.9 by 0.6 in D1 (p < 0.01) and by 0.3 in D2 (p < 0.01), but it increased from 6.1 by 1.8 in D3 (p < 0.01). The mean digester effluent TS increased from 3.4% by 0.1% (p > 0.05) in D1, but it decreased from 4.9% by 1.3% in D2 (p < 0.05) and from 12.3% by 4.8% in D3 (p < 0.01). All three digesters significantly increased NH 4 -N concentrations by 21.4–81.8% (p < 0.05), but insignificantly changed TKN and TP concentrations (p > 0.05). Effects of AD on all metal concentrations were mixed and were insignificant (p > 0.05) because of large concentration variations. However, study of a ratio quotient (q Mg) using magnesium (Mg) as the reference discovered accumulation of NH 4 -N, copper, potassium, and sodium, but loss of TKN, TP, iron, manganese, zinc, and calcium during AD for D2 and D3. The impact of AD conversion was closely related with types of feedstock (on pH) and HRT (on TS and NH 4 -N). The results of this study can assist in developing strategies for cleaner production using AD in an environmentally sustainable manner. [ABSTRACT FROM AUTHOR]

• Major components in cow and camel milk were analyzed by infrared spectroscopy. • NIR and MIR spectroscopy gave different results. • Identification of bias requires validation with reference methods. Milk samples (150 cow and 217 camel milk samples) were analyzed for protein, fat, lactose and total solids by near and mid-infrared transmission spectroscopy. Excellent positive correlations between the two methods were obtained for both types of milk (p < 0.001); for protein (r ≥ 0.96), fat (r ≥ 0.99), lactose (r = 0.82) and total solids (r = 0.90). The mean of the relative difference ((MIR values – NIR values)/0.5 (MIR values + NIR values) × 100%) for cow and camel milk were, for protein (+8.2 & +13.4%), fat (− 9.3 & +0.9%), lactose (− 5.4 & − 0.7%) and total solids (− 2.2 & − 3.4%), respectively. The difference between the two methods may be due to the effects of differences in milk homogeneity, especially with respect to casein micelles and fat globules. [ABSTRACT FROM AUTHOR]