Biological hydrogen production from synthetic wastewater by an anaerobic migrating blanket reactor: Artificial neural network (ANN) modeling

Background: This study aimed to evaluate an anaerobic migrating blanket reactor (AMBR) for biological hydrogen production, and also to investigate its capability to treat synthetic wastewater. Methods: A five-compartment AMBR (9 L effective volume) was made by Plexiglas and seeded with thermal pretreated anaerobic sludge at 100°C for 30 minutes. The AMBR was operated at mesophilic temperature (37 ± 1°C) with continuous fed of synthetic wastewater at five organic loading rates (OLRs) of 0.5 to 8 g COD/L.d. Results: It was revealed that as the OLR increased from 0.5 to 8 g COD/L.d, the hydrogen production and also volumetric hydrogen production rate (VHPR) improved. Increasing the OLR over this range, led to a decrease in the average hydrogen yield from 1.58 ± 0.34 to 0.97 ± 0.45 mol H2/mol glucose. The concentration of both volatile fatty acids (VFAs) and solvents kept increasing with OLR. During the AMBR operation, the dominant soluble end products (SEPs) were acetic and butyric acids in all of the OLRs studied. Conclusion: Based on the results, the hydrogen yield was related to the acetate/butyrate fermentation. The artificial neural network (ANN) model was well-fitted to the experimental obtained data from the AMBR, and was able to simulate the chemical oxygen demand (COD) removal and hydrogen production. Keywords: AMB reactor, Fatty acids, Fermentation, Hydrogen, Wastewater treatmen

Combination of hydrodynamic cavitation with oxidants for efficient treatment of synthetic and real textile wastewater

In this study, the degradation of direct red 89 (DR89) dye from synthetic wastewater was assessed by lab-scaled hydrodynamic cavitation (HC) combined with different oxidants such as periodate (PI), persulfate (PS), and oxalic acid (OA). The degradation tests were carried out by combining the three oxidants in the absence of HC, and using HC with only one of the oxidants (HC/OA, HC/PS, and HC/PI) or with all combined (HC/PS/OA/PI). In all processes, the degradation constants followed first-order reaction kinetics, being the highest one that of the HC/PS/OA/PI process, equal to 2.01 × 10− 1 min− 1 . The degradation of DR89 was affected by pH, initial dye concentration, and reaction time. The degradation efficiency increased when pH decreased obtaining the best results at pH 3.0 due to favorable conditions for the generation and persistence of radical species. The degradation of the dye improved with increasing dose of OA, PS and PI. The best results were achieved using dosages of OA, PS, and PI of 100.0, 125.0, and 150.0 mg L− 1 , respectively. The quenching experiments revealed the presence of • OH, SO4 •− , IO3 • , O2 •– , and 1 O2 in the HC/PS/OA/PI process, while • OH, SO4 •− and IO3 • were the dominant responsible radicals. The rate constants of the individual processes were used to calculate the value of the synergetic coefficient of HC/PS/OA/PI process. At the optimum conditions, the calculated synergetic coefficient was 15.39. The effectiveness of the HC/PS/OA/PI process in the removal of color and COD from real textile wastewater was also investigated and exhibited the 96.23 ± 1.92 % and 93.84 ± 0.94 % reduction of color and COD after 70 min reaction time, respectively. The results showed that the combined process can be a useful technology for the treatment of textile wastewateThe authors thank the Isfahan University of Medical Sciences of Iran (Project No. 198124 and Ethics code: IR.MUI.RESEARCH. REC.1398.500) for financial support of this wor

Proposal of upgrading Isfahan north wastewater treatment plant: An adsorption/bio-oxidation process with emphasis on excess sludge reduction and nutrient removal

There is a rising challenge in managing the activated sludge process due to excess sludge disposal from the wastewater treatment plant and inadequate effluent quality due to the stricter standard of effluent quality. Hence, the incorporation of oxic-settling-anoxic process and ultrasonic waves in the return sludge line was proposed to assess the excess sludge reduction and nutrient removal in the adsorption/bio-oxidation activated sludge process as a proposal upgrading. The results indicated that sludge production from adsorption/bio-oxidation process could be reduced using oxic-settling-anoxic and ultrasonic by 50% at each studied mixed liquor suspended solids level. Compared to the adsorption/bio-oxidation process, the total and soluble chemical oxygen demand removal efficiencies in adsorption/bio-oxidation process with oxic-settling-anoxic and ultrasonic slightly decreased suggesting a lysis phenomenon. During the operation of adsorption/bio-oxidation process with oxic-settling-anoxic and ultrasonic, the total Kjeldahl nitrogen removal efficiency improved in A and B stages, with 38.3 ± 8.1% and 83.1 ± 6.5% versus 36.8 ± 14.5% and 75.1 ± 7.3%, respectively. According to the stoichiometric calculations, in B stage of adsorption/bio-oxidation process with oxic-settling-anoxic and ultrasonic, the soluble available ultimate biochemical oxygen demand and net NO3 produced for denitrification were 69.5 and 43.8 mg/L, respectively. Overall, the experimental data revealed that the adsorption/bio-oxidation process with oxic-settling-anoxic and ultrasonic produced lower excess biological sludge and better total Kjeldahl nitrogen removal efficiency compared to the adsorption/bio-oxidation system alone

Magnetized Activated Carbon Synthesized from Pomegranate Husk for Persulfate Activation and Degradation of 4-Chlorophenol from Wastewater

The compound 4-chlorophenol (4-CP) is known to be a highly toxic compound having harmful effects on human health and the environment. To date, the removal of 4-CP by advanced oxidation processes (AOPs) has attracted tremendous attentions. The persulfate-based AOPs show higher oxidation, better selectivity, wider pH range, and no secondary pollution compared to the traditional Fenton-based AOPs. Carbon materials with low cost and chemical stability are useful for the activation of persulfate (PS) to produce reactive species. Herein, we magnetized activated carbon synthesized from pomegranate husk (MPHAC). By using 4-CP as a model organic pollutant, tests of the activation of PS via MPHAC for the removal of 4-CP were performed. Batch processes were carried out to study the influence of different parameters (initial solution pH, catalyst dose, PS dose, and initial 4-CP concentration) on the adsorption of 4-CP on PHAC with ferric oxide (Fe3O4-PHAC). The results show that under the obtained optimal conditions (MPHAC dose: 1250 mg/L, PS dose: 350 mg/L, solution pH 5, an initial 4-CP concentration of 100 mg/L, and a contact time of 60 min), a 4-CP removal factor of 99.5% was reached by the developed MPHAC/PS system. In addition, it was found that reusing MPHAC in five successive cycles is feasible because the catalyst in the last cycle kept exhibiting a high potential for 4-CP absorption, indicating the economically viable procedure. Therefore, this study provides a comprehensive understanding on the degradation of 4-CP by the magnetized activated carbon persulfate system

Electron flow of biological H2 production by sludge under simple thermal treatment: Kinetic study

Mixed culture sludge has been widely used as a microbial consortium for biohydrogen production. Simple thermal treatment of sludge is usually required in order to eliminate any H2-consuming bacteria that would reduce H2 production. In this study, thermal treatment of sludge was carried out at various temperatures. Electron flow model was then applied in order to assess community structure in the sludge upon thermal treatment for biohydrogen production. Results show that the dominant electron sink was acetate (150–217 eˉ meq/mol glucose). The electron equivalent (eˉ eq) balances were within 0.8–18% for all experiments. Treatment at 100 °C attained the highest H2 yield of 3.44 mol H2/mol glucose from the stoichiometric reaction. As the treatment temperature increased from 80 to 100 °C, the computed acetyl-CoA and reduced form of ferredoxin (Fdred) concentrations increased from 13.01 to 17.34 eˉ eq (1.63–2.17 mol) and 1.34 to 4.18 eˉ eq (0.67–2.09 mol), respectively. The NADH2 balance error varied from 3 to 10% and the term eˉ(Fd↔NADH2) (m) in the NADH2 balance was NADH2 consumption (m = −1). The H2 production was mainly via the Fd:hydrogenase system and this is supported with a good NADH2 balance. Using the modified Gompertz model, the highest maximum H2 production potential was 1194 mL whereas the maximum rate of H2 production was 357 mL/h recorded at 100 °C of treatment

Efficiency of Constructed Wetland Vegetated with Cyperus alternifolius

The treatment of municipal wastewater from Yazd city (center of Iran) by constructed wetland vegetated with Cyperus alternifolius was assessed. Two identical wetlands with a total working volume of 60 L and 10 cm sandy layer at the bottom were used. First wetland (W1) was control and had no Cyperus alternifolius plant. Second wetland (W2) had 100 Cyperus alternifolius shrubs with 40 cm height. Influent wastewater was provided from Yazd's septic tanks effluents and after a 4-day retention time in wetlands, reactors effluent was sampled for parameters analysis. Results show that chemical oxygen demand (COD), –N, –N, and –P in W1 were reduced to 72%, 88%, 32%, and 0.8%, and in W2, these parameters were removed in values of 83%, 81%, 47%, and 10%, respectively. In both wetlands, the highest and lowest removal efficiencies were related to COD and phosphorus, respectively. Also, the removed phosphorus can be released to stream when the soil saturated or influent phosphorus decreased and when the plant died. After a 4-day-retention time, the W2 wetland showed a statistically significantly lower COD and –N in comparison with W2 wetland

Alternative Disinfection Methods Use to Control of Microbial Quality and Shelf-life of Raw Eaten Vegetables (Case Study)

Background: Fresh-cut vegetables are particularly susceptible to microbial growth and, therefore, the use of an effective sanitizer on this product is great importance. Method: The common vegetable  types obtained from a local wholesale market in Isfahan and washed with different common disinfectants such as edible salt, sodium hypochlorite, electrolyzed water (EW), complex disinfectant, calcium hypochlorite, and dishwashing liquid. Disinfection time and concentration select according to the Official Protocol in Iran. A total of 126 samples including Mint, Savory, parsley, Garden cress, Common Purslane, Chives, Basil, Radish, and mixed vegetables were analyzed for total bacteria, total coliform bacteria, and E. coli. Result: Results demonstrated that calcium hypochlorite has the best efficiency for total coliforms in separate vegetable of parsley, Garden cress, Common Purslane, Chives, Radish, with100% efficacy. For total coliforms BGB (Brilliant Green Broth) test, complex disinfectant and calcium hypochlorite have 100% removal for all of the vegetables. E.coli test result showed in four vegetables not E.coli but for another vegetable except Dishwashing Liquid efficiency was 100%. Among all disinfectants, EW has a high efficiency for mixed vegetables. For Basil disinfected with edible salt and mint washing with complex disinfectant, Eimeria parasite and in savory disinfected with calcium hypochlorite Hook worm parasitic was found. Shelf-life was between 1 to 5 days. Conclusion: Our research suggested that EW has a good effect for total coliforms, fecal coliforms, E.Coli, and helmet eggs removal, also save the vegetable shelf life

Alternative Disinfection Methods Use to Control of Microbial Quality and Shelf-life of Raw Eaten Vegetables (Case Study)

Background: Fresh-cut vegetables are particularly susceptible to microbial growth and, therefore, the use of an effective sanitizer on this product is great importance. Method: The common vegetable  types obtained from a local wholesale market in Isfahan and washed with different common disinfectants such as edible salt, sodium hypochlorite, electrolyzed water (EW), complex disinfectant, calcium hypochlorite, and dishwashing liquid. Disinfection time and concentration select according to the Official Protocol in Iran. A total of 126 samples including Mint, Savory, parsley, Garden cress, Common Purslane, Chives, Basil, Radish, and mixed vegetables were analyzed for total bacteria, total coliform bacteria, and E. coli. Result: Results demonstrated that calcium hypochlorite has the best efficiency for total coliforms in separate vegetable of parsley, Garden cress, Common Purslane, Chives, Radish, with100% efficacy. For total coliforms BGB (Brilliant Green Broth) test, complex disinfectant and calcium hypochlorite have 100% removal for all of the vegetables. E.coli test result showed in four vegetables not E.coli but for another vegetable except Dishwashing Liquid efficiency was 100%. Among all disinfectants, EW has a high efficiency for mixed vegetables. For Basil disinfected with edible salt and mint washing with complex disinfectant, Eimeria parasite and in savory disinfected with calcium hypochlorite Hook worm parasitic was found. Shelf-life was between 1 to 5 days. Conclusion: Our research suggested that EW has a good effect for total coliforms, fecal coliforms, E.Coli, and helmet eggs removal, also save the vegetable shelf life

The global burden of cancer attributable to risk factors, 2010-19 : a systematic analysis for the Global Burden of Disease Study 2019

Background Understanding the magnitude of cancer burden attributable to potentially modifiable risk factors is crucial for development of effective prevention and mitigation strategies. We analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 to inform cancer control planning efforts globally. Methods The GBD 2019 comparative risk assessment framework was used to estimate cancer burden attributable to behavioural, environmental and occupational, and metabolic risk factors. A total of 82 risk-outcome pairs were included on the basis of the World Cancer Research Fund criteria. Estimated cancer deaths and disability-adjusted life-years (DALYs) in 2019 and change in these measures between 2010 and 2019 are presented. Findings Globally, in 2019, the risk factors included in this analysis accounted for 4.45 million (95% uncertainty interval 4.01-4.94) deaths and 105 million (95.0-116) DALYs for both sexes combined, representing 44.4% (41.3-48.4) of all cancer deaths and 42.0% (39.1-45.6) of all DALYs. There were 2.88 million (2.60-3.18) risk-attributable cancer deaths in males (50.6% [47.8-54.1] of all male cancer deaths) and 1.58 million (1.36-1.84) risk-attributable cancer deaths in females (36.3% [32.5-41.3] of all female cancer deaths). The leading risk factors at the most detailed level globally for risk-attributable cancer deaths and DALYs in 2019 for both sexes combined were smoking, followed by alcohol use and high BMI. Risk-attributable cancer burden varied by world region and Socio-demographic Index (SDI), with smoking, unsafe sex, and alcohol use being the three leading risk factors for risk-attributable cancer DALYs in low SDI locations in 2019, whereas DALYs in high SDI locations mirrored the top three global risk factor rankings. From 2010 to 2019, global risk-attributable cancer deaths increased by 20.4% (12.6-28.4) and DALYs by 16.8% (8.8-25.0), with the greatest percentage increase in metabolic risks (34.7% [27.9-42.8] and 33.3% [25.8-42.0]). Interpretation The leading risk factors contributing to global cancer burden in 2019 were behavioural, whereas metabolic risk factors saw the largest increases between 2010 and 2019. Reducing exposure to these modifiable risk factors would decrease cancer mortality and DALY rates worldwide, and policies should be tailored appropriately to local cancer risk factor burden. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.Peer reviewe

Factors Associated with Breastfeeding in the First Hour after Birth, in Baby Friendly Hospitals, Shiraz-Iran

Introduction: Clinical policies of “10 steps of breast feeding” proposed by World Health Organization (WHO) can promote breast feeding. The goal of this study was to evaluate breast feeding in the first hour after birth and its relation to the influencing factors. Material and methods: In this cross-sectional study, the data is related to mothers and infants referring to two baby friendly hospitals of Shiraz. The data were selected through convenience sampling method by interview, questionnaires and reviewing of medical records. Results : In this study 257 mothers and infants were studied. 94% of mothers were breast feeding and 5.8% of them were not able to breast feed. 63.8% of the infants had started breastfeeding an hour post delivery. 79% of the infants had been given to their mothers post delivery. 68.9% mothers given birth in public hospitals versus 52.2% of mothers given birth in private hospitals,75.5 % of mothers having gestational age greater than 37 weeks versus 38.9% of mothers  having gestational age less than 37 weeks, 60.1% of infants weighing more than 2500 grams versus 43.5% of infants weighing less than 2500 grams. 88% of mothers with vaginal delivery versus 40.2% of mothers with cesarean section all had started breast feeding in the first hour after birth. Conclusion: Initiation of breastfeeding in the first hour after birth was higher in mothers having diploma, gestational age greater than 37 weeks, previous history of breastfeeding, vaginal delivery, infant weighing more than 2500 gram, lack of infant disease, lack of hospitalization in NICU, rooming in, lack of prelactal feeding and delivery in public hospitals