Total Solids Research Articles

Performance of Dairy Factory Wastewater Treatment Plant (Case Study of Pasuruan Dairy Factory East Java)

The 'ILP' company produces bottled milk with chocolate, melon, strawberry, and vanilla flavors in colorless HDPE (High-Density Polyethylene) plastic bottles and aluminum foil covers. The 'ILP' dairy industry wastewater treatment process stages include bar screen, grease trap, equalization tank, flocculation-coagulation, primary clarifier, aeration tank/activated sludge, and secondary clarifier. The research aims to determine the performance of the dairy factory's WWTP (Wastewater Treatment Plant) in terms of TSS (Total Suspended Solids) and COD (Chemical Oxygen Demand) parameters. This field-scale research was carried out for approximately 5 weeks (35 days) at the wastewater treatment plant of the ILP company. Wastewater sampling is carried out at the inlet point, equalization tank, primary sedimentation, aeration tank, and outlet point of WWTP. Wastewater examination conducted in the company's internal laboratory, including temperature, pH, total suspended solids (TSS), and chemical oxygen demand (COD). The dairy factory WWTP (wastewater treatment plant) can generate TSS (total suspended solids) effluent of 22 mg/L and COD (chemical oxygen demand) of 26.8 mg/L to meet the applicable wastewater quality standards. The treatment efficiency of the dairy industry WWTP for TSS is 94.7% and COD is 98.1%.

High rate methanogenesis and nitrogenous component transformation in the high-solids anaerobic digestion of chicken manure enhanced by biogas recirculation ammonia stripping

High-solids anaerobic digestion is a promising technology for treating animal manure. However, the high nitrogen content in chicken manure leads to severe ammonia inhibition, thereby hindering the application of this technology for chicken manure. This study operated a high-solid anaerobic system feeding the reactor with 20 % total solids (TS) chicken manure for 650 days to investigate whether the anaerobic metabolic performance could be enhanced by adopting biogas recirculation ammonia stripping. The results show that, with ammonia stripping, the total ammonia nitrogen (TAN) was reduced from 8.2 to 3.0 g/L. The methanogenic activity was enhanced 1.3 – 2.9 fold. This led to a low level of volatile fatty acids (VFA, 0.6 g/L) and a high methane yield of 0.3 L/g-volatile solids (VS). Protein decomposition was facilitated under stripping conditions and correlated with a higher abundance of protein decomposition bacteria and enhanced methane production. The dynamics of ammonium formation and removal were illustrated for different stripping conditions. The ability to maintain low ammonium and the carbon and nitrogen balance was also verified. The proven effectiveness observed in this long continuous experiment may provide a foundation for further demonstrating the high-solids anaerobic digestion of chicken manure.

Nematodes Can Substitute Artemia in a Co-Feeding Regime for Pacific White Shrimp Post-Larvae Reared in a Biofloc Nursery System.

This study evaluated nematodes as an alternative to live Artemia when provided in a co-feeding regime to Pacific white shrimp (Penaeus vannamei) post-larvae (PL) reared in a biofloc nursery system. A 20-day experiment employing PL11 was performed for an evaluation of four dietary groups: control [C] (fed exclusively with a dry commercial feed); artificial Artemia [AA] (dry feed composed of extracted and processed Artemia cysts and dry commercial feed); live Artemia and dry commercial feed [LA]; and nematodes and dry commercial feed [N] (Panagrolaimus sp. dry nematodes). The diets were provided twice a day, with the remaining six feed provisions being a commercial dry feed for all experimental groups. A biofloc system was chosen as it offers a potentially sustainable approach to intensive shrimp farming. Alkalinity and pH in the [N] group were significantly higher in the last 5 days of the experiment (p < 0.05), likely causing the significantly lower nitrite levels observed in that same group (p < 0.05). Total and volatile suspended solids were significantly lower in the two live feed groups when compared with [C] and [AA] (p < 0.05). Although PL fed the dry diets exhibited higher growth rates (p < 0.05), the [N] and [LA] groups presented significantly higher final survivals (p < 0.05). No differences were found for survival after a salinity stress test (p ≥ 0.05). These results suggest that nematodes can successfully substitute Artemia in a co-feeding regime for P. vannamei PL reared in biofloc nursery systems.

Multivariate Analysis and Optimization Scheme of the Relationship between Leaf Nutrients and Fruit Quality in ‘Bingtang’ Sweet Orange Orchards

Citrus trees require a balanced and adequate supply of macronutrient and micronutrient elements for high yield and fruit quality. Foliar nutrient analysis has been widely used in fruit-tree nutrient diagnosis and fertilization calculation. However, there is no information on ways to produce optimal fruit quality in sweet oranges. In the present study, fruit and leaf samples were collected from 120 ‘Bingtang’ sweet orange [Citrus sinensis (L.) Osbeck] orchards during four consecutive years (2019–2022). Parameters of leaf nutrition and fruit quality were analyzed based on these samples. Diagnostic results based on leaf classification standards indicated that the most deficient elements were Ca, Mg, and B, followed by N and Zn. Fruit quality, determined by single fruit weight (SFW), fruit shape index (FSI), total soluble solids (TSS), titratable acidity (TA), vitamin C (Vc), and maturation index (MI = TSS/TA) during fruit maturation, exhibited inconsistent responses to leaf mineral nutrition concentrations. The leaf-nutrient optimum values for high quality of the ‘Bingtang’ sweet orange fruit were ranges of 2.41–4.92% N, 0.10–0.28% P, 1.30–2.11% K, 2.99% Ca, 0.26–0.41% Mg, 340–640 mg/kg S, 89.65–127.46 mg/kg Fe, 13.48–51.93 mg/kg Mn, 2.60–13.84 mg/kg Cu, 15.59–51.48 mg/kg Zn, and 53.95 mg/kg for B. These results suggest the leaf-nutrient optimum values for diagnosis can be used not only to identify the nutrient constraints but also to provide guidance for the establishment of fertilization regimes in citrus cultivation.

Evaluation of Acid Lime (Citrus aurantifolia Swingle) Genotypes for Growth, Yield and Quality Traits

A study on evaluation of acid lime genotypes for growth, yield and quality traits was carried out at Citrus Research Station, Vannikonenthal, Manur Taluk and Tirunelveli district, Tamil Nadu during the year 2021–2023. Twenty five acid lime genotypes were selected for the experiment. Observation on quantitative traits such as tree height (m), tree spread (m), canopy spread (m2), tree girth (cm), leaf lamina length (mm), number of fruits/tree, mean fruit weight (g), fruit length (cm), fruit girth (cm), fruit volume (cc), number of seeds per fruit, yield/tree (kg) and qualitative traits such as total soluble solids (°Brix), acidity (%), juice content (ml), fruit juice percentage (%) and ascorbic acid content (mg/100g) were recorded. The present study results revealed that genotype SCA 19 recorded the highest values for the traits such as tree height (3.49 m), tree spread (3.58 m2 E-W; 3.74 m2 N-S), canopy spread (6.57 m3), leaf lamina length (58.40 mm) and tree girth (13.66 cm). However, genotype SCA 06 registered the lowest tree spread character. In the case of yield traits, genotype SCA 19 registered the highest values in number of fruits per tree (1080), mean fruit weight (58.75 g), yield per tree (57.89 kg per tree), number of seeds (9.10), fruit length (8.50 cm), fruit girth (4.90 cm) and fruit volume (54.81 cc). Regarding quality traits, SCA 19 observed the highest values viz., TSS (6.71˚Brix), acidity (6.78 %), ascorbic acid content (26.50 mg/100 g), fruit juice percentage (52.1 %) and juice content (46.0 ml). Hence, acid lime genotype SCA 19 recommended for further evaluation in different parts of Tamil Nadu.

Water quality index of selected borehole locations in Jos North LGA of Plateau State, Nigeria

Prevalence of water borne diseases is a public health concern. The study assessed the quality of selected borehole waters in Jos North for their potability. The physicochemical parameters were assessed in addition to chlorides, phosphates, nitrates, and sulphates, total solids, total dissolved solids, total suspended solids, total hardness, using standard methods. Atomic absorption spectrophotometry used for elemental analysis of samples for manganese, lead, cadmium, copper and zinc. microbial analysis was carried out to test for presence of anaerobic bacteria, coliforms, Escherichia coli, Salmonella typhi, yeast and mould, Staphylococcus aureus using the plate count method. Water Quality Index by Weighted Arithmetic Index Method. Results ranged from 22.19-56.22 mg/L (chlorides), 0.00-0.07 mg/L (phosphates), 0.11-0.19 mS/cm (conductivity), 141.40-169.40 mg/L (alkalinity) and 86.70-160 mg/L (TSS). Kyan Primary school had Mn 0.632 mg/L against 0.500mg/L recommended by WHO. Microbial analysis revealed that Kyan primary school had 1 cfu per 100 mL water for E. coli, Salmonella typhi, yeast and mould. This indicated faecal contamination. The WQI revealed Village hostel, Kyan Village, Gadabiu had values of 6.54, 19.41, 10.97 are potable, Government College, Angwan Jarawa, Kyan Primary school had 28.90, 61.50, 93.60 are potable, poor, very poor, not potable.

Assessment and monitoring of leather effluent discharge from Dewas and Ranipet and their computational approach.

The swift pace of industrialization, urbanization, and burgeoning populations propel the surge in demand for manufactured goods and infrastructure. The wastewater produced during leather processing comprises a cocktail of organic and inorganic chemical contaminants that have the potential to affect the environment. This study focuses on conducting a comparative physico-chemical, analytical,in vitro, and in silicotoxicity assessment and monitoring of leather effluent discharged from two different areas, namely, Dewas and Ranipet. The physicochemical analysis of collected effluents revealed higher levels of biochemical oxygen demand, chemical oxygen demand, total dissolved solids, total suspended solids, and heavy metals than the permissible limit fixed by the Central Pollution Control Board (CPCB). The X-ray powder diffraction analysis of both samples identified the existence of crystalline and amorphous phases. The functional composition of compounds was identified through the analysis of Fourier-Transform Infrared Spectroscopy, which revealed the existence of C-H, O-H, N-H, C = O, C=C, and C≡C stretching vibrations. A variety of compound derivatives, including amines, organic acids, organometallic compounds, alcohols, hydrocarbons, esters, aldehydes, ketones, aromatic, and organogermanium, were identified by Gas Chromatography-Mass Spectrometry. An assessment and monitoring of the phytotoxicity of effluent on the germination of Vigna radiata seeds reveals that (100%) of both Dewas and Ranipet leather effluents inhibited seed germination by 33.34% and 100%. The incorporation of Absorption-Distribution-Metabolism-Excretion-Toxicity (ADMET) analysis improved comprehension of the toxicity profiles of the GC-MS-identified compounds. Moreover, the result of docking studies revealed that cytochrome P450 showed the highest binding affinity towards 1,3-benzodioxol-2-one, hexahydro-cis with an affinity score of - 7.1kcal/mol. The overall research revealed that the leather effluents from Dewas and Ranipet exhibit significant toxicity, highlighting the necessity of better wastewater management. In the future, innovative treatment methods and environmental friendly processes can be developed to minimize the detrimental effects of leather effluents.

Potential of acoustic sensors for real-time monitoring of physicochemical properties of milk protein concentrate during ultrafiltration

Ultrafiltration (UF) is the step for concentrating protein in milk and whey prior to evaporation and drying in dairy ingredient production, e.g. milk protein concentrate (MPC). To optimize UF process, it is important to monitor changes in product/process parameters. Two in-line sensors with outputs: 1. bulk acoustic wave (BAW), acoustic viscosity (AV); 2. surface acoustic wave (SAW), acoustic impedance (AI) and acoustic transmission (AT), were evaluated to measure MPC physicochemical properties (total solids (TS), density, protein and apparent viscosity) during UF. Trials were quintuplicated in a UF membrane pilot-plant, to concentrate feed (TS 11.36–19.10%). Models for predicting MPC physicochemical properties developed by acoustic parameters performed well, especially by AI and AT, with R2 > 0.963, SEP <1.076 to predict apparent viscosity, and R2 > 0.980, SEP <0.627 for all other properties’ prediction. This study demonstrated the potential of both acoustic sensors for UF process monitoring.

Analysis of the nutritional composition, biological activities, and phenolic metabolic bioactive module of cherry tomatoes

This study analyzed the overall nutritional composition of 87 cherry tomato varieties and evaluated the antioxidant, hypoglycemic, and hypolipidemic activities of the top 30 varieties with excellent overall quality. In addition, the phenolic metabolic characteristics of cherry tomatoes were determined via phenolic metabolomics, and the bioactive module “phenolic-DPPH” was identified. There was extensive interspecies variation in total soluble solids, titratable acid, lycopene, chlorophyll, γ-aminobutyric acid, total phenolics, total flavonoids and multivitamins, and different color groups presented unique nutritional compositions. The comprehensive nutritional value of the 56 varieties is greater than that of the Millennium variety. Phenolic substances are closely related to DPPH free radical scavenging activity. A total of 484 phenolic substances were identified, among which 5′-methoxymatairesinoside and 6-hydroxykaempferol-7,6-O-diglucoside are key antioxidant components. Our research provides valuable resources and insights for the selection of functional cherry tomato varieties and the identification of phenolics with important biological activities.

Effects of maternal dietary supplementation with antioxidants on clinical status of mares and their foal

BackgroundThe peripartum period constitutes a delicate physiological moment in mares showing a transient state of oxidative stress. Diet supplementation with antioxidants during pregnancy in women appears to have a beneficial effect on mother and neonate health. The aim of this work was to evaluate the effects of diet supplementation with a commercial product containing a mix of antioxidants (Oxyliver®, Candioli) on the length of gestation, weight, and haemato-biochemical parameters in Italian Salernitano mares and their newborn foals. Eight late-term pregnant mares were randomly divided into two groups: Antiox group receiving 30 g/day of antioxidants, and Car group receiving the same amount of carrot powder, from 290 to 320 days of gestation. The following parameters were evaluated in mares: weight, colostrum composition, haemato-biochemical parameters, progesterone, and cortisol blood concentrations, along with blood oxidant/antioxidant status. Assessments were conducted at specific time points: immediately before the start of diet supplementation (T0), 15 days after (T1), at the end of diet supplementation (T2), within 8 h after parturition (T3), and 10 days post-partum (T4). Foal parameters such as weight, haemato-biochemical values, cortisol concentration, and blood oxidative stress variables were assessed within 8 h of birth (TF0) and at 10 days of age (TF1).ResultsPregnancy was shorter in the Antiox group (P < 0.05) compared with the Car group; the foals’ weight increase of group Antiox (40%) was higher (P < 0.05) compared to those of the Car group (28.6%). The colostrum of the Antiox group exhibited higher levels of Brix, total solids, protein, nonfat solids, casein, urea, density, free fatty acids, and glucose, while lower levels of fat and lactose were observed compared to the Car group (P < 0.05). Mares’ serum albumin at T1 and T3, creatinine, glucose, total proteins, total bilirubin, AST, and ALT at T3 were lower in Antiox than in the Car group. No significant differences were found in foals.ConclusionsWhile the limited sample size and the potential variability of evaluated parameters, the observed outcomes suggest that Oxyliver® supplementation in mares might safely decrease gestation length and enhance liver function, thus potentially improving colostrum quality and offspring development.

Enzymatic catalytic dynamics of lactic-acetic acid co-fermentation: Effect of cellulase on the physicochemical, phytochemicals, volatiles, and antioxidant activity of jujube puree extracts

The processing of jujube (Ziziphus jujuba) is imperative due to its esteemed status and rich pharmacological properties despite its sensory challenges and short shelf-life. Traditional drying methods preserve jujube quality but complicate bioactive compound extraction due to the conjugated polysaccharide matrix. This study addresses the gap in research on enzymatic pretreatment by investigating the use of cellulases to break down the rigid cellulose structure, thus enhancing the efficiency of subsequent fermentation processes. Besides, this research explored the catalytic dynamics of cellulase pretreatment in lactic-acetic acid co-fermentation to improve jujube puree's functional and quality properties. Methodologies involved applying cellulase at concentrations of 1 %, 3 %, and 5 % (v/v) at 40 °C for 4 hours, followed by fermentation with Lactobacillus plantarum CGMCC 3346 and Acetobacter pasteurianus (Ap CICC 20001, CGMCC 1.41). Results indicated that fermentation and enzyme hydrolysis significantly influenced jujube puree's physicochemical and sensory attributes. Fermentation increased densities and moisture content, while unfermented and enzyme-treated samples had higher total soluble solids (TSS) values (11.00–11.50 °Brix). Enzyme concentration affected the reducing sugar and protein content, with higher enzyme concentrations (5 %EF) producing lighter products (L* = 52.00). Total phenolic content increased with fermentation, particularly in the 3 %EF treatment (351.89 mg GAE/100 g FW), while flavonoid and flavonol contents peaked in the 5 %EF (426.33 mg RE/100 g FW) and 3 %EF (25.80 mg QE/100 g FW) treatments, respectively. Proanthocyanidin content was highest at moderate enzyme concentrations, notably in the 3 %EF treatment (715.95 mg CE/100 g FW). Fermentation also enhanced antioxidant properties and altered flavor profiles by decreasing acetoin levels and increasing acid and ester production. This study highlights the significance of the combinative effect of enzyme concentration and fermentation processes in augmenting jujube puree extracts' nutritional and sensory qualities.

Quality analysis and assessment of representative sea buckthorn fruits in northern China

Sea buckthorn (SB) primarily grows in northern China and is rich in nutritional components, making it popular among consumers. This study aims to select suitable SB varieties for processing by analyzing physicochemical components, color, taste, and volatile compounds. The results showed that the physicochemical content of Chinese SB from Gansu were as follows: total soluble solids 13.50 ± 0.37°Brix, titratable acidity 6.46 ± 0.39 %, ascorbic acid 578 mg/100 g, polyphenols 517 mg/100 g, and flavonoids 194 mg/100 g, which were higher than those of the other four SB samples; the content of organic acids was relatively abundant. Taste analysis via electronic tongue indicated that Chinese SB had the highest ANS (sweetness) value and the lowest SCS (bitterness) value, exhibiting the richest flavor. Gas chromatography-mass spectrometry analysis showed that Gansu Chinese SB had a rich variety of volatile components, totaling 74. In summary, Gansu Chinese SB is a variety suitable for processing.

Enhanced biochemical, microbial, and ultrastructural attributes of reduced-fat labneh through innovative microalgae integration.

Reduced-fat labneh, while offering health benefits, often presents a challenge due to its diminished nutritional profile compared to full-fat varieties. Microalgae, such as Spirulina platensis and Chlorella vulgaris, are increasingly explored for their potential to fortify foods with essential nutrients. This study innovatively investigates the use of these microalgae to enhance the quality of reduced-fat labneh. The effect of incorporating different concentrations of both microalgae was investigated at different concentrations (0.25, 0.5, and 1%) on nutritional profile (including total solids, fat, protein, carbohydrates, essential amino acids, unsaturated fatty acids, pigments, and phenolic compounds), antioxidant activity, texture, sensory attributes, and viability of the starter culture. The findings revealed that 0.25 and 0.5% concentrations of both microalgae positively influenced the sensory characteristics of the labneh and significantly enhanced its nutritional profile. However, a 1% concentration negatively impacted sensory qualities. Chlorella vulgaris enrichment resulted in higher pH values but compromised texture attributes. Importantly, both microalgae varieties enhanced the viability of the starter culture during 21 days of refrigerated storage. The scanning electron microscope images provide visual evidence of the microstructural changes in labneh with varying concentrations of microalgae and over different storage periods. This research establishes the optimal concentrations for individual microalgae enrichment in reduced-fat labneh, offering valuable insights into their potential to improve both nutritional and sensory aspects. However, it's important to mention that while both microalgae have similar effects, they might differ in their specific impacts due to their unique nutritional profiles and physical properties. Therefore, further investigations could explore optimizing a microalgae mixture and its potential application in functional food development.

Influence of earthworm population density on the performance of vermifiltration for treating liquid dairy manure.

The dairy industry has seen notable changes in the last couple of decades, including increased size of farms and regional concentrations of dairies. This has resulted in substantial manure production in small geographical areas, raising environmental concerns. Vermifiltration, an emerging low cost and eco-friendly technology for treating wastewater, was evaluated to assess the influence of earthworm population density on the performance of a laboratory-scale vermifilter treating liquid dairy manure. We monitored the reduction efficiencies of various components, including total nitrogen (TN), ammonium-nitrogen (NH4 +-N), nitrate-nitrogen (NO3 --N), total phosphorus (TP), orthophosphate (ortho-P), chemical oxygen demand (COD), total solids (TS), and total suspended solids (TSS), in treated dairy wastewater. This evaluation was conducted at 0; 5000; 10,000; and 15,000 earthworm densities per cubic meter (m-3) of bedding. Reduction efficiencies of 41%-89% (TN), 46%-86% (NH4 +-N), 34%-74% (NO3 --N), 3%-17% (TP), 18%-38% (ortho-P), 35%-66% (COD), 24%-54% (TS), and 50%-87% (TSS) were observed with higher earthworm densities exhibiting greater reduction efficiencies. Notably, the densities of Eisenia fetida at 10,000 and 15,000 earthworms m-3 showed no significant difference in vermifilter performance. This suggests that increasing the Eisenia fetida density beyond 10,000 earthworms m-3 may not further improve the vermifilter's performance in treating dairy wastewater. This study's findings indicate that using vermifiltration with an earthworm population density of 10,000 earthworms m-3 could effectively mitigate the negative environmental impact of liquid dairy wastewater at a low cost and sustainably.

Biotic and Abiotic Components of The River

This study offers a comprehensive analysis of the physico-chemical parameters of the Sarodha Dam in Kabirdham, Chhattisgarh, over three distinct periods: pre-autumn, autumn, and post-autumn of 2007. Key parameters examined include temperature, velocity, total solids, total suspended solids, total dissolved solids, turbidity, pH levels, dissolved oxygen content, free CO2 concentration, biochemical oxygen demand (BOD), chemical oxygen demand (COD), alkalinity, chlorides, sulphate levels, and fish species identification. The research identified 36 distinct fish species within the dam, underscoring the biodiversity present. Historically, water has been a crucial resource for human survival and development, with rivers playing a vital role globally. However, pollution from sewage and industrial effluents threatens these vital water bodies, leading to significant environmental and health issues. Despite advances in water treatment, urban piped water often remains contaminated, resulting in waterborne diseases such as jaundice, cholera, typhoid, and gastroenteritis. Pollution impacts rivers through chemical degradation and disruption of ecosystems, highlighting the need for interdisciplinary approaches to monitor and manage water quality effectively.

Does the diversity of vegetation and diatoms correlate with soil and water factors in a tropical cloud forest's complex land use/land cover scenario?

Soil and water characteristics in micro basins with different land uses/land cover (LULC) can influence riparian vegetation diversity, stream water quality, and benthic diatom diversity. We analyzed 18 streams in the upper part of the La Antigua River basin, México, surrounded by cloud forests, livestock pastures, and coffee plantations. Concentrations of P, C, and N were elevated in the humus of forested streams compared to other land uses. In contrast, cations, ammonium, and total suspended solids (TSS) of water streams were higher in pastures and coffee plantations. These results indicate that LULC affects stream chemistry differently across land uses. Vegetation richness was highest (86-133 spp.) in forest streams and lowest in pastures (46-102), whereas pasture streams had the greatest richness of diatoms (9-24), likely due to higher light and temperatures. Some soil and water characteristics correlated with both true diversity and taxonomic diversity; soil carbon exchange capacity (CEC) correlated with vegetation diversity (r = 0.60), while water temperature correlated negatively (r = - 0.68). Diatom diversity was related to soil aluminum (r = - 0.59), magnesium (r = 0.57), water phosphorus (r = 0.88), and chlorophyll (r = 0.75). These findings suggest that land use affects riparian vegetation, while physical and chemical changes influence diatom diversity in stream water and soil. The lack of correlation between vegetation and diatom diversity indicates that one cannot predict the other. This research is an essential first step in understanding how land use changes impact vegetation and diatom diversity in mountain landscapes, providing valuable insights for environmental monitoring and conservation efforts in tropical cloud forests.

Efficiency of Backwashing in Removing Solids from Sand Media Filters for Drip Irrigation Systems

Sand media filters are especially recommended to prevent emitter clogging with loaded irrigation waters, but their performances rely on backwashing. Despite backwashing being a basic procedure needed to restore the initial filtration capacity, there is a lack of information about the solid removal efficiency along the media bed depth. An experimental filter with a 200 mm silica sand bed height was used to assess the effect of two operation velocities (30/45 and 60/75 (filtration/backwashing) m h−1) and two clogging particles (inorganic sand dust and organic from a reclaimed effluent) on the efficiency of backwashing for removing the total suspended solids retained in different media bed slices. The average solid removal backwashing efficiency was greater with organic particles (78%) than with inorganic ones (64%), reaching its maximum at a 5–15 mm bed depth. A higher operation velocity increased the solid removal efficiency by 16%, using organic particles, but no significant differences were observed with inorganic particles. The removal efficiencies across the media bed were more uniform with organic particles (63–89%) than with inorganic (40–85%), which makes it not advisable to reduce the media height when reclaimed effluents are used. This study may contribute to future improvements in sand media filter design and management.

Assuring reclaimed water quality using a multi-barrier treatment train according to the new EU non-potable water reuse regulation

In this study, we evaluated the ability of various pilot-scale treatment train combinations to meet the microbial requirements of the new European non-potable water reuse regulation 2020/741. The study utilized non-disinfected secondary effluent from the wastewater treatment plant in Schweinfurt, Germany, as feedwater for two pilot-scale treatment trains. The first, a reference treatment train (Train A), consisted of filtration and UV disinfection as specified for reclaimed water class A in the EU regulation. The second, an advanced treatment train (Train B), included ceramic ultrafiltration (UF), ozonation, biological activated carbon filtration (BAC), and final UV disinfection. Based on a Monte Carlo simulation for Train A, the EU requirements for pathogen removal were not met when an average UV dose of 400-600 J m−2 was applied. This shortcoming was likely due to a moderate transmittance range (50–65 %), resulting in decreased UV fluence. These findings suggest that operational conditions for disinfection should be more clearly specified to ensure consistent pathogen inactivation both during validation and regular operation. In contrast, treatment train B successfully met the requirements of the EU regulations by reducing pathogens to below the detection limit. The UF membrane demonstrated a positive effect on the overall log reduction values (LRVs) throughout the water reclamation system. It also enhanced the efficiency of downstream processes, such as ozonation and UV disinfection, by lowering total suspended solids and turbidity. However, even without the UF membrane, treatment train B was still able to meet the pathogenic EU requirements for non-potable reuse applications. Furthermore, the study observed that the inclusion of biologically activated carbon (BAC) filtration requires a final disinfection step (e.g., UV disinfection) to prevent the potential occurrence of heterotrophic bacteria that proliferate in the BAC filter. For process validation it is recommended to use at least two different virus surrogates (MS2 and PhiX174), rather than just one or total coliphage as required in the EU regulation.

Excessive boron fertilization-induced toxicity is related to boron transport in field-grown pomelo trees.

Boron (B) is an essential micronutrient for plant growth and development; however, the process of B toxicity in citrus production is still poorly understood. We proposed a hypothesis that B toxicity in citrus trees is related to the characteristics of B transport from soil to leaf or fruit. For this, a field experiment was conducted for two treatments, control (B free or without B) and B fertilizer treatment (100 g Na2B4O7·10H2O plant-1), to investigate the effects on plant growth, nutrient uptake, fruit yield and quality, and B transport in 10-year-old pomelo trees [Citrus grandis (L.) Osbeck cv. Guanximiyou]. Our results showed that excess B fertilization directly led to B toxicity in pomelo trees by dramatically increasing soil total B and water-soluble B contents. B toxicity induced interveinal chlorosis in leaves and decreased leaf biomass and function, resulting in a decreased 45.3% fruit yield by reducing 30.6% fruit load and 21.4% single fruit weight. Also, B toxicity induced changes in mineral elements between leaf positions and fruit parts, in which the concentrations of B, potassium, and magnesium were increased while those of nitrogen and iron were decreased. Under B toxicity conditions, fruit quality parameters of total soluble solids (TSS), TSS/titratable acidity (TA), total soluble sugar, sucrose, pH, vitamin C, and total phenol contents decreased, which were regulated by the lower carbohydrate production in new leaves and the lower transport capacity in old leaves. Moreover, B toxicity significantly increased the transfer factor and bio-concentration factor of B in pomelo plants, with higher levels in leaf organs than in fruit organs. Taken together, excess B fertilization-induced B toxicity in pomelo trees, with induced growth inhibition and nutrient disorder, results in reduced fruit yield and quality, which are related to B transport from soil to organs. The findings of this study highlight the understanding of B toxicity in citrus plants and strengthen B management in pomelo production for high yield and high quality.

Productivity and competitive dominance of freshwater filamentous macroalgal cultivars for nutrient bioremediation of primary municipal wastewater

ABSTRACT Algal bioremediation using macroalgae is a promising approach to wastewater treatment. This study compared the productivity and bioremediation performance of the freshwater filamentous algal cultivars; Klebsormidium flaccidum, Oedogonium calcareum, and Oedogonium sp., in primary municipal wastewater in outdoor high-rate filamentous algal pond mesocosms. K. flaccidum had the highest biomass productivity (3.09 g dry weight m−2 day−1 ± 0.20 SE) and bioremediation performance, reducing total ammoniacal-N by 51% to 14.80 mg L−1 (± 0.81 SE), nitrate-N by 59% to 0.30 mg L−1 (± 0.02 SE), and dissolved reactive phosphorous by 15% to 3.52 mg L−1 (± 0.07 SE). This cultivar achieved the greatest reductions in total suspended solids (54%), carbonaceous biochemical oxygen demand (93%), and chemical oxygen demand (74%). K. flaccidum and Oedogonium sp. reduced Escherichia coli by 98%. Competitive dominance of K. flaccidum and Oedogonium sp. was assessed in bicultures at three stocking densities. By day 12, K. flaccidum's proportion increased from 50 to 64% (± 6.1 SE) and 73% (± 5.0 SE) at a stocking density of 0.25 g and 0.5 g FW L−1, respectively. Based on superior biomass productivity, bioremediation performance, and competitive dominance, K. flaccidum was identified as a target cultivar for bioremediation of primary municipal wastewater.