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Myco-remediation of Dairy Wastewater by Naturally Attenuated Aspergillus sp. Responsible for Sulfate Reduction
2022
Sharma, Neha | Meher, Alok Kumar | Bhagwani, Harshita | Chahar, Darshan | Yadav, Neetu | Kohli, Vipra | Shourie, Bhavyam | Arunachalam, Kalirajan | Siankuku, Munaska
Dairy industries generate enormous volumes of waste water which are significantly rich in organic compounds; contributing to high BOD, COD and sulfates. As a mandate to ‘treat’ effluents generated by different unit operations in a dairy industry, current treatment methods rely on physico-chemical, mechanical and conventional biological interventions. This approach remains unviable because of cost intensiveness and excessive energy usage. Additionally, the significant lowering of pollution indicators remains a daunting task with inlet and outlet parameters. With these identifiable gaps, our study was aimed to screen bio-efficacious, naturally attenuated fungal isolates to lower exceeding levels of sulfate in effluents released by dairy industry. Effluent samples were collected from Effluent Treatment Plant (ETP) of Jaipur Dairy, Rajasthan Dairy Co-operation Limited (RCDF), Jaipur. For mycological investigations, qualitative screening was carried out in Potato Dextrose Agar (PDA) supplemented with Calcium Sulfate (CaSo4) (0.1g/L). The most promising fungal isolates belonging to Aspergillus sp. was characterized based on its cultural and microscopic characteristics. Microcosm study was conducted by supplementing Aspergillus sp. in Untreated Dairy Effluent (UDE) for a period of 7 days at Room Temperature (RT) under static conditions. Following the incubation phase, mycelial mesh (plug) was indicative of exponential fungal growth. Effluent seeded with Aspergillus sp. and abiotic controls were spinned at 5000 rpm for 15 minutes to eliminate biomass. Sulfate estimation was carried out in Cell Free Extract (CFE) of both experimental and control group. A significant reduction of 67.3% was observed (p<0.05) with respect to positive control and 8.4% when contrasted with abiotic control.
Show more [+] Less [-]Kinetic Characteristics and the Performance of Up-Flow Biological Aerated Filters (UBAF) for Iraqi Municipal Wastewater
2022
Kalash, khairi R. | Al-Furaiji, Mustafa | Ahmed, ِAmer N.
This study utilized kinetic models to study the treatment efficiencies of a laboratory-scale up-flow biological aerated filters reactor (UBAF). The treatment efficiency of a model reactor was studied using different operating conditions of the hydraulic retention times, organic loading rates, and kinetic parameters. As a result of the calculations, the second-order and modified Stover/Kincannon models are appropriate. The substrate removal rate constant K2(S) was 1.7 per day for the reactor, with a correlation coefficient of 0.9979. Utilizing the modified Stover/Kincannon model, the coefficient of the determined concentration was 0.9987; 0.9265; and 0.9685 for Chemical oxygen demand (COD); ammonium nitrogen (NH4+-N); and Total Nitrogen (TN), respectively. The calculation of the saturation value constants and maximum utilization rate for Chemical oxygen demand (COD); ammonium nitrogen (NH4+-N); and Total Nitrogen (TN) was performed using the modified Stover-Kincannon model were 178.57 and 201.80 for COD; 1.876 and 4.6 for NH4 +-N; 3.823 and 6.644 for TN, respectively. It is possible to determine the kinetic parameter for removing COD, NH4+-N, and TN from wastewater by using the modified Stover-Kincannon model.
Show more [+] Less [-]Aliphatic and Aromatic Hydrocarbons in the Coastal Sediments of the Kharg Island in the Persian Gulf
2022
Hadjizadeh Zaker, Nasser
Kharg Island in the Persian Gulf is the place for the major oil export terminals of Iran and hosts several large oil related industries. Coastal environment of the Kharg Island is rich in coral reefs. This paper presents concentrations and sources of aliphatic and aromatic hydrocarbons in the sediments from the coastal area of the island. The concentration of hydrocarbons in 14 seabed sediment samples from water depths of 13-20 m around the island were measured by gas chromatography (GC). Total Petroleum Hydrocarbon (TPH) concentrations in sediment samples ranged from less than 1 to 133 μg/g indicating low to moderate levels of oil pollution. Spatial distributions of TPH concentrations indicated no oil pollution in the southern part of the island, higher oil pollution levels near oil terminals and correlation with fine particles. Total Polycyclic Aromatic Hydrocarbons (∑PAHs) concentrations in sediment samples ranged from near zero to 6210 ng/g, indicating non to highly, but mainly moderately polluted levels. SPAHs concentrations, except at one station, were all less than the NOAA sediment quality guideline value for the effects range low. Developed indices for pollutant origins showed that hydrocarbons in all sediment samples collected in the study area had petrogenic origin. The results also indicated that the emissions from gas flares in the island were the main source of aromatic compounds in the sediment samples.
Show more [+] Less [-]The state of metallic contamination of Saf-Saf river sediments (Skikda – Algeria)
2022
Rouidi, Sonia | Hadef, Azzedine | Dziri, Hamdi
The sediments of Saf-Saf river (North eastern of Algeria), were studied in order to evaluate their degree of contamination by trace metal elements. Six heavy trace metals (Cd, Cr, Cu, Fe, Mn and Ni) were researched at the surface sediments of nine study stations. Since these different metallic elements appear as tracers of anthropogenic pollution; various evaluation indices of metallic contamination were studied (Igeo, FC, DC, IPS and PEC). The results of these indices are consistent and reveal a polymetallic sediment contamination by several heavy metals essentially by Fe, Mn and Cd, with an abundance of Fe and Mn. Sediment pollution index, indicates that sediments at all stations are hazardous (IPS ˃ 20). The environmental quality of Saf-Saf river sediments, were realized by comparing the metal contents with the values of the TEC and the PEC has showed that the metals Cd, Cu and Mn present a great danger of toxicity.
Show more [+] Less [-]Assessment of the limnological characteristics of Lake Bosomtwe in the Ashanti Region of Ghana
2022
Owusu-Boateng, Godfred | Ampofo-Yeboah, Akwasi | Agyemang, Thomas Kwaku | Sarpong, Kofi
The quality of the water from Lake Bosomtwe was assessed to aid in the conservation decision on the lake. Twenty-six parameters of physico-chemical, bacteriological, and organic effects and major and trace ions were evaluated using the principal component analysis. The levels of these parameters were also compared with surface water benchmarks of Ghana EPA, WHO, EU, US EPA and CCEM. As prescribed by the benchmarks of these regulatory bodies, the mean levels of temperature, pH, dissolved oxygen, total suspended solids, total dissolved solids, nitrates, phosphate, biochemical oxygen demand, chemical oxygen demand, total hardness, conductivity, alkalinity, turbidity and fluorine did not signal any lake pollution, but sulphate, total and faecal coliforms, chlorophyll-a, cadmium and mercury showed pollution tendencies. Temperature, pH, dissolved oxygen, total suspended solids, total dissolved solids, nitrates, phosphate, sulphate and total coliform bacteria were found to be the main parameters that drive 71.2% of the limnological characteristics of the lake water and deserve careful consideration in designing conservation strategies for the lake.
Show more [+] Less [-]Monitoring of Trihalomethanes and its Cancer Risk Assessment in Drinking Water of Delhi City, India
2022
Mazhar, Mohd. Aamir | Ahmed, Sirajuddin | Husain, Azhar | Uddin, Rahis
The current study determines the concentrations of trihalomethanes (THMs), and the cancer risk associated with them. The tap water sampling was done from the command area of nine water treatment plants (WTPs) of Delhi, India. THMs levels in the water samples from eighteen distribution points were investigated for one year. The cancer risk (CR) related to THMs by different exposure routes i.e., ingestion, dermal absorption, and inhalation, was assessed for males and females. The THM levels varied between 11.41 µg/L to 175.54 µg/L in the distribution system, having a mean level of 77.58 µg/L. The average concentrations of THMs exceeded the maximum permissible limit given by Indian Standards. The concentration of chloroform was maximum, followed by bromodichloromethane, dibromochloromethane, and bromoform. For males and females, the mean value of total CR was 5.09E-05 5.70E-05, respectively. As the THMs levels were high, the total CR value was also more than the negligible level of risk i.e., 1.0 x 10-6 through all exposure routes.
Show more [+] Less [-]Review on the use of Microalgae Biomass for Bioplastics Synthesis: A Sustainable and Green approach to control Plastic Pollution
2022
Nandal, Meenakshi | Khyalia, pradeep | Ghalawat, Anu | Jugiani, Himani | Kaur, Manpreet | Laura, Jitender
Worldwide there is an immense demand for plastic material that results in “white pollution”. Petrochemical-based plastic is used all over the world which leads to adverse impacts on every sphere of the earth. However, many steps have been taken to control this plastic pollution globally, such as chemical treatments, plastic waste incineration, sanitary landfilling, and 7 R programs. Still, plastic pollution is one of the major international problems. Non-biodegradable plastic would not eradicate from our environment until we have an economically feasible and more biodegradable substitute. In recent years algae, especially microalgae, have got attention worldwide, owing to their various applications. Microalgae is one of the sustainable ways of bioplastic synthesis as during cultivation it also purifies wastewater. This review paper has summarized various species of microalgae used for the synthesis of bioplastic, their cultivation system, and methods for bioplastic production by using microalgae biomass, followed by multiple challenges, solutions, and future prospects.
Show more [+] Less [-]Spatiotemporal variation of particulate matter & risk of exposure in the indoor-outdoor residential environment: a case study from urban city Delhi, India
2022
Yadav, Arun | Ghosh, Chirashree
Humans spend close to 90% of their time within the indoor environment. Deteriorating indoor air quality, especially high PM10, PM2.5 and PM1 is slowly becoming a major concern. A study was carried out, for two years, to characterize the spatiotemporal variation of PM in the indoor-outdoor environment across different residential setups (R1, R2, R3, and MC) in the Delhi region. The study established correlation between monthly variations of Indoor/Outdoor (I/O) ratios and meteorological factors. The results showed Spatio-temporal variation in the average mass concentrations of PM10 recorded peak values during the winter season (avg. 514± 72.15 µg/m3) and minimum concentration was observed during monsoon (avg. 91.41± 22.64 µg/m3) months. Among all the sites, the mixed cluster (MC), a residential cum commercial zone reported the highest particulate matter concentration (avg. 308.10 ±37.23 µg/m3) and while R2 reported the least concentration (avg. 244.9± 27.65 µg/m3) within the indoor environment. The I/O ratios of particulate matter were observed to be highest in January (I/O ratio1.6) and lowest in June month (I/O ratio 0.8). PM10, PM2.5, and PM1 dynamics were found to be critically influenced by meteorological factors, regular household activities, and diverse building designs. The short- or long-term exposure of particulate pollutants (beyond the permissible limits) can increase the probability of acute health effects, so there is an utmost requirement to collect better and systematic information about actual exposure levels experienced in different urban residential environments.
Show more [+] Less [-]Emission Risk Assessment of Toxic Gases of Floating Roof Storage Tanks
2022
Doregar Zavareh, Razieh | Dana, Tooraj | Roayaei, Emad | Monavari, Seyed Masoud | Jozi, Seyed Ali
Events such as the emission of toxic gases are possible on floating roof storage tanks. Since gasoline is a high-consumption and volatile product stored in adjacent oil depots or large cities, it is necessary to assess their emission risk. Given that the multi-criteria methods allow the identification of and assessment of the indicators well and allow the participation of expert experts, so the FAHP method has been used to identify and assess the risk before the emission of toxic gases. The results showed the importance of 7 factors among 36 factors, 3 of which were related to equipment error. The DOW'S CEI method was used to assess the emission risk if the event occurred. This method provides safe boundaries based on Emergency Response Planning Guidelines (ERPGs), where the results indicate the settlement placement around the oil repository in the range of the predicted concentration at all three levels of ERPG.
Show more [+] Less [-]Assessment of groundwater and surface water pollution by hazardous metals, using multivariate analysis and metal pollution index around the old Sidi Kamber mine, NE Algeria
2022
khelfaoui, malika | Benaissa, Amina | Kherraf, Sihem | Madjram, Mohamed Salah | Bouras, Ibtissem | Mehri, karima
In order to evaluate the impact on water quality of the abandoned Sidi Kamber mine in Skikda, NE Algeria, Pb, Zn, Cd, Fe, Cu, Mn and Ni metals were collected at surface water and groundwater, from twenty eight sites located near the mine. Conventional hydrochemical methods, heavy metal pollution index (HPI) and multivariate statistical analysis techniques: correlation matrix (CM), principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used. Surface water results show that El-Souk River has a high level of pollution, but Guenitra dam water is less contaminated. Regarding the groundwater results, the wells and springs are not suitable for drinking. The overall quality estimated by HPI values of surface and groundwater are poor; they may pose a potential health risk to the local population. The PCA and HCA suggest that surface water and groundwater are contaminated by two sources: anthropogenic and natural. According to the obtained results, surface water and groundwater pollution state of this area raises serious concerns about health and environment.
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