TDS Concentrations Research Articles

Characteristics and pollution indices of leachates from municipal solid waste landfills in Iranian metropolises and their implications for MSW management

Leachate from municipal solid waste landfills poses a significant threat to aquatic ecosystems due to poor management practices. This study evaluated thirty leachate samples from Iranian metropolises using the Leachate Pollution Index (LPI). Various parameters, including BOD₅, COD, TDS, pH, EC, heavy metals, turbidity, PAHs, phthalates, and humic acid, were analysed. The BOD₅ levels ranged from 350 to 20,000 mg/L, and the COD levels ranged from 2,000 to 90,000 mg/L. The TDS content varied between 14.7 and 67 g/L, while the turbidity ranged from 15 to 186 NTU. Heavy metals were present but within standard limits. The phthalate concentrations ranged from 6 to 150.8 mg/L, and the humic acid concentrations ranged from 135 to 2,200 mg/L. Naphthalene was the most frequent hydrocarbon detected. The LPIs were less than 30 for all the samples, with the highest in Ahvaz and the lowest in the treated samples from Tehran. This study highlights the presence of persistent organic and hazardous contaminants in Iran’s municipal landfills, emphasizing the need for effective leachate treatment and improved waste management practices. Enhanced final disposal methods, increased waste recovery, and improved solid residue separation are crucial for preventing further leachate production and environmental contamination.

Beneath the surface: assessing pollution levels near major solid waste dumpsites in Lagos, Nigeria.

Effective solid waste management is a critical environmental challenge, particularly in rapidly growing Global South countries like Nigeria. This issue is exacerbated by burgeoning populations, lax waste regulations, and the widespread practice of open dumping. The deterioration of soil quality and alteration of water quality are major consequences of open waste dumping, posing significant environmental and public health risks. This study aims to assess the environmental risk and pollution status of soil and water resources near major dumpsites in Lagos. It aims to offer insights that can inform targeted interventions and policy measures not only in Lagos but also in comparable urban settings worldwide. Results indicated that important soil parameters, including TN (11.89-13.83mg/kg), pH (6.45-7.35), sulfate (36.71-39.49mg/kg), phosphate (9.31-14.39mg/kg), and electrical conductivity (342-566 µS/cm), were significantly affected by the dumpsites. Additionally, concentrations of heavy metals varied, with some exceeding permissible limits set by international standards, highlighting the environmental challenges posed by improper waste disposal in urban settings like Lagos. The analyzed parameters for water were mostly within acceptable limits, indicating a lesser impact of the waste dump on water resources. Water samples from boreholes and hand-dug wells near three dumpsites showed that pH, TDS, and heavy metal concentrations were mostly within WHO limits, with borehole water deemed safe for drinking and hand-dug wells suitable for cleaning. To alleviate the environmental impacts of open dumpsites, it is recommended to implement effective waste segregation, recycling programs, controlled landfilling, and investment in waste treatment technologies, along with regular water quality monitoring to prevent further pollution and protect public health. While these measures offer opportunities, they also face significant challenges due to financial and land constraints. Therefore, strong public awareness, infrastructure investment, and government commitment are essential, along with coordinated efforts among the government, private sector, and communities.

Mitigating Membrane Fouling in Abattoir Wastewater Treatment: Integration of Pretreatment Step with Zwitterion Modified Graphene Oxide–Polyethersulfone Composite Membranes

Composite polyethersulfone (PES) membranes containing N-aminoethyl piperazine propane sulfonate (AEPPS)-modified graphene oxide (GO) were integrated with either of the two pretreatment processes (activated carbon (AC) adsorption or polyelectrolyte coagulation) to assess their effectiveness in mitigating membrane fouling during the treatment of abattoir wastewater. The AEPPS@GO-modified membranes, as compared to the pristine PES membranes, showed improved hydrophilicity, with water uptake increasing from 72 to 118%, surface porosity increasing from 2.34 to 27%, and pure water flux (PWF) increasing from 235 to 673 L.m−2h−1. The modified membranes presented improved antifouling properties, with the flux recovery ratio (FRR) increasing from 59.5 to 93.3%. This study compared the effectiveness of the two pretreatment processes, AC, coagulation, and the integrated system (coagulation/AC-UF membrane), in the removal of natural organic matter (NOM) and improvement of abattoir wastewater’s pH, electrical conductivity, TDS, and turbidity. The integrated systems produced improved water quality in terms of pH, EC, TDS, turbidity, and organic content. The fluorescence excitation–emission matrix (FEEM) analysis exhibited almost no fluorescence peak post-treatment following organic loading removal. The quality of the water met the South African non-potable water reuse standards. The sole membrane treatment systems exhibited good fouling resistance without the pretreatment systems; however, integrating these systems can offer extended longer filtration periods, thereby assisting in cost aspects of the abattoir wastewater treatment system.

Occurrence and distribution of atrazine in groundwater from agricultural areas in China

There has been heavy application of chemical pesticides to farmland worldwide. As a state with a heavy emphasis on farming, China has extensively applied chemical pesticides to farmlands. Atrazine (ATZ), one of the most widely used herbicide in the world, has been used in large quantities in weed control in many crops, which poses a relatively large threat to groundwater utilization and agricultural safety. A nationwide sampling and analysis of ATZ in 8146 groundwater monitoring wells from 10 main grain producing areas were conducted during 2019. The results showed that the detection rate of ATZ in groundwater was 40.79 %, with detected concentrations up to 2.86 μg/L. ATZ detection rate was significantly higher in phreatic aquifers than confined aquifer. The concentration of ATZ decreased significantly with the depth increasing, the detected depth of ATZ in groundwater was varied from 5 to 1100 m, and 70.27 % of the detected ATZ was distributed in the depth of 0–51.8 m. The detection rate of ATZ in most north regions lower than south regions in China, and ATZ with high concentration was mainly occurred in southern regions. ATZ is more likely to migrate into the groundwater in the water resource rich areas. The concentration of ATZ decreased with TDS increasing, 74.39 % of the ATZ was detected in groundwater with TDS concentration <1 g/L. The hydrochemical type of groundwater in ATZ-enrichment environment were mainly Ca-HCO3 and Mixed type. According to classification and regression tree analysis, the high ATZ detection rate were closely related with groundwater depth (<51.8 m) and high organic matter content.

Evaluation of water quality and heavy metal contamination in Cauvery River: Tamil Nadu region India

Abstract Comprehensive water quality control is a fundamental requirement for environmental preservation and the sustainable development of communities around the globe. To showcase the importance of local quality controls in identifying the sources of pollution, a case study was conducted to analyze the quality of drinking water from different locations along the Cauvery River from Mettur to Trichy (200 km) in Tamil Nadu, India. The quality of water samples from different locations was indexed and compared with the World Health Organization and Indian Standards of water quality. The results indicate some high local values of TDS, hardness, and chloride content. These high values may be due to effluents from industries, dying factories, and sewage from the urban areas on the banks of the Cauvery River. This is most prevalent near Mohanur, where industrial waste and effluents were directly linked into the river. The results emphasize the importance of local quality control for accurately pinpointing the factors affecting the environment.

Bioactive compounds and digestible starch variability of rice, maize, green gram, and soy grains with different levels of germination

SummaryGermination is a sustainable and economical process that can enhance the bioactivities of commonly consumed cereal and pulses, contributing to healthier diets. Its effectiveness in increasing bioactives depends on the germination conditions. This study examined the impact of varying germination periods (2, 4, 6, and 8 days) following 12 h of steeping on rice, maize, green gram, and soy, focusing on key bioactive compounds, including total polyphenols, flavonoids, and total digestible starch. Cereal and pulses germinated for eight days demonstrated a significantly higher (P &lt; 0.05) total polyphenol and flavonoid content along with elevated antioxidant activity. Antioxidant activity strongly correlated to increased total polyphenol and flavonoid levels throughout the extended germination period. Moreover, the total digestible starch content (TDS) in rice, maize, and soy increased significantly (P &lt; 0.05) because of the hydrolysis of starch molecules, while green gram showed twofold decrease in TDS, indicating the impact of germination on TDS content may differ across the type of cereal and pules. Using locally grown Sri Lankan grain varieties, such as rice, maize,green gram,and soy, this study fills the gap in existing database on the investigation of bioactive compounds and total digestible starch content, exploring the potential of germination of cereal and pulses to use in nutritionally rich products in the food and agriculture industry with a focus on sustainable food systems and healthier eating habits.

Assessment of Groundwater Quality for Human Uses

Evaluating the quality of groundwater holds utmost importance in determining its suitability for safe consumption. This study delved into the groundwater conditions in selected regions of southern Iraq (Thiqar government), specifically Al-shatra and Al-naser districts. Physical and chemical water parameters were examined including, pH, electrical conductivity, turbidity, total dissolved solids, alkalinity, nitrates, nitrites, fluoride, sulfate, hexavalent chromium, copper, manganese, and iron. The results demonstrated the quality of ground water was not suitable for human uses according to WHO and Iraqi guidelines. Heavy metals and anions contaminates have not influenced on the human health and the environment due to their higher concentrations less than the acceptable value. However, other parameters have concentrations higher than the allowable value. The maximum concentration of TDS was 1955 mg/l at Al-zamil (Al-naser) (W8) and the turbidity was slightly more than the WHO standard. The concentration of alkalinity was higher than the healthy value.

Experimental Investigation of Tannery wastewater by Electrocoagulation method

Abstract Treating tannery wastewater poses a significant challenge due to its composition, comprising biogenic materials from hides and a diverse range of organic and inorganic chemicals. Experimental procedures were conducted using an electrochemical reactor employing sacrificial electrodes—mild steel as both anode and cathode—in a unceasing process. Numerous working parameters such as current density and electrolysis duration were examined to achieve optimal reduction in presence of turbidity, total solids, COD, BOD, TDS, and Chromium content. Enhanced reductions in COD, BOD, TDS, and chromium content were observed at higher flow rates. The applied current density also notably impacted the reduction efficiency of COD, BOD, TDS, and chromium content. Investigation into the electro coagulation method employing short cell current (1A) and solvable mild steel electrodes revealed their efficacy compared to aluminium electrodes, particularly in chromium removal, achieving over 90% removal efficiency. However, the use of mild steel electrodes resulted in the formation of a black precipitate characteristic of iron (II) sulphides during the treatment, although effectively reducing effluent coloration. The removal efficiency of chloride, however, remained lower, at less than 12%. A comprehensive discussion on the mechanisms involved in the removal of COD, chromium, total dissolved salts, total solids, chloride and coloration using soluble mild steel electrodes was presented. The predominant role of the electrode was highlighted by treating tannery wastewater with mild steel electrodes, followed by filtration, resulting in removal rates of 68.0% for chemical oxygen demand, 43.1% for chromium, 55.1% for total dissolved salts and 84.3% for coloration, considering initial concentrations of 2850 mg/L, 230 mg/L, 100 mg/L, 100 mg/L, and a 256- fold dilution, respectively.

Traceability of Phreatic Groundwater Contaminants and the Threat to Human Health: A Case Study in the Tabu River Basin, North China

Groundwater is the main clean water resource in northern China, and its quality is critical for both human health and social sustainable development. Due to complex anthropogenic and/or geogenic processes, the sources of groundwater contaminants are not easy to determine. The Tabu River Basin, located in northern China, is an agriculture and pasture interlaced area in which phreatic groundwater is the predominant water resource for domestic and agricultural purposes. Groundwater with abnormally high levels of NO3−, F−, and TDS was observed here based on 87 groundwater samples collected from the phreatic aquifer in 2022. In this study, hydrogeochemical and isotopic methods were used to trace groundwater contaminants in the phreatic aquifer, and a risk assessment was conducted to analyze their threat to human health. The results indicated that NO3− in the phreatic groundwater primarily originated from manure, the high concentration of TDS was highly associated with irrigation, and the enrichment of F− was mainly controlled by geogenic factors, including alkaline condition, competitive adsorption, the dissolution of fluorine-bearing minerals, and cation exchange. A principal component analysis (PCA) showed that both anthropogenic (PC1, 50.7%) and geogenic (PC2, 19.9%) factors determined the quality of the phreatic groundwater in the study area. The human health risk assessment demonstrated that 98.9%, 92.0%, and 80.5% of the groundwater samples exceeded the permissible limit of the total noncarcinogenic risk for children, adult females, and adult males, respectively. The monitoring results from 2022 to 2023 suggested that phreatic groundwater contamination could not be mitigated through natural attenuation under the existing external pressures. Measures need to be taken to decrease the contamination of phreatic groundwater and enhance the groundwater sustainability in the Tabu River Basin. The findings of this study can provide a reference for sustainable groundwater development in the Tabu River Basin and other arid and semi-arid regions worldwide.

Chemical characteristics, formation mechanisms, and geological evolution processes of high-salinity coal reservoir water in the Binchang area of the southern Ordos Basin, China

The chemical characteristics of coal reservoir water are important for studying the formation and enrichment of biogenic coalbed methane (BCM). Based on geological and sampling test data, this paper studied the geochemical characteristics and formation mechanisms of high-salinity coal reservoir water (CRW) in the Jurassic Yan'an Formation of the Binchang area in the southern Ordos Basin. The results show that the TDS contents of the CRW in the Binchang area are between 7577.38 and 15,138.61 mg/L (av. 13,268.95 mg/L), which is high-salinity brackish water. The ion types of CRW are mainly Na+, Cl− and HCO3−, and the correlations between TDS and Na+ and Cl− are close to 1. The Piper trilinear diagram indicates that the evolution direction of the CRW is deep concentrated brine, and the hydrochemical type is the NaCl type. The 127I concentrations of CRW are between 285 and 484 μg/L, which are much higher than the values of 55.88 μg/L for seawater. The results of 129I dating show that the minimum age of the CRW in the study area is between 6.7 Ma and 39.97 Ma, which is much younger than the actual geological age of the Yan'an Formation. The hydrogen and oxygen isotope results show that the CRW in the study area experiences an apparent oxygen drift, indicating that the coal reservoir of the Yan'an Formation has good sealing and a long retention time for the CRW. The hydrodynamic factors show that the hydrodynamic conditions of the coal reservoir are weak, and the primary ions in the CRW originated from the dissolution of salt rocks. The main ion differentiation indices show that high-salinity coal seam water is mainly formed by evaporation, and the ion exchange between CRW and the surrounding rock and the alternating adsorption of cations in water are very weak. Evaporation and diagenesis lead to an increase in the contents of Na+, Cl− and I+ in coalbed water, which in turn leads to an increase in the total dissolved solids contents of CRW and its evolution toward concentrated brine. The genesis and evolution of the CRW in the study area are affected by the combination of the relationships among the paleoclimate, aquifers and aquifuges, and tectonic evolution processes. The CRW in the study area has experienced five evolution stages, i.e., sedimentary water and diagenetic water, high-salinity infiltration water, primary mixed water, paleoatmospheric precipitation recharge water, and secondary mixed water. The above understanding can provide a basis for studying the formation period and accumulation mechanism of BCM and provide a hydrogeological basis for water resource utilisation and pollution prevention and the control of high-salinity water.

Hydrochemical Characteristics and Controlling Factors of the Mingyong River Water of the Meili Snow Mountains, China

The hydrochemical characteristics of rivers are affected by many natural factors, such as the nature of watershed bedrock, watershed environment, vegetation, and human activities. Examining the hydrochemistry of a river can provide insights into the baseline hydrological conditions, the geochemical environment, and the overall water quality of the river. In order to examine the hydrochemical characteristics and controlling factors of the water in the Mingyong River, a total of 154 water samples were gathered from the glacier meltwater, midstream, and downstream regions. Firstly, the findings revealed that the dominant cations are Ca2+ and Mg2+, while the dominant anions are HCO3− and SO42−. The mass concentration order of cations is Ca2+ &gt; Mg2+ &gt; Na+ &gt; K+, and for anions, it is HCO3− &gt; SO42− &gt; NO3− &gt; Cl−. The average concentration of TDS in the river water is 81.69 mg·L−1, with an average EC of 163.63 μs·cm−1 and an average pH of 8.99. Temporal variations in ion concentrations exhibit significant disparities between the glacier melting and accumulation periods. High ion concentration values are primarily observed during the glacier accumulation period, while values decrease during the glacier melting period due to increased precipitation. The river water in the study region is categorized as (HCO3− + SO42−)-(Ca2+ + Mg2+) type. Secondly, the Pearson correlation analysis indicates clear relationships between different parameters, indicating that the major ions were mostly influenced by materials from the Earth’s crust. The primary principal source of solutes in the water of the Mingyong River is rock weathering. The cations and anions present in the river water are derived from the breakdown of carbonate rocks and the dissolving of substances from silicate rocks. However, the influence of carbonate rocks is more significant compared to that of silicate rocks. Finally, the Mingyong River water is suitable for agricultural irrigation with minimal land salinization damage, making it appropriate for agricultural purposes but not suitable for people and animals to drink from directly.

Effects of Rice Mill Wastewater on Cocoon Production and Total Population of Earthworm, Eisenia Fetida (Savigny 1826) under Laboratory Condition

Water scarcity can be overcome through the reuse of treated wastewater for irrigation especially in arid and semiarid regions. However, there are several potential environmental and health risks associated with this practices. Improved plant growth and nutrients for microorganisms are also gotten from wastewater which has high nutritive value. This study investigated the effect of rice mill waste water on cocoon production and total population of earthworm Eisenia fetida under laboratory conditions. A total of five hundred (500) clitella earthworms were used for this study. The physico-chemical parameters of the rice mill wastewater were analyzed using standard methods of APHA-AWWA-WEF (2000). The study on the cocoon production and total population of E. fetida were conducted from 0 to 100% wastewater (0, 25, 50, 75 and 100%) by serial dilution for a period of 60 days to assess the suitability of rice mill wastewater for irrigational purpose. The significant difference between treatments was tested by one-way ANOVA. The wastewater had an alkaline pH (8.5), low sulphate (0.95 mg/l), DO (3.10mg/l) and COD (2.0mg/l); moderate concentration of TDS (421mg/l), calcium (47.7 mg/l), phosphate(102.27 mg/l) and high concentration of conductivity (20.50 dsm-1), total solid (2550mg/l), total dissolved solids (2028 mg/l), total hardness (100 mg/l) and sodium (25.0 mg/l), earth population(53.2) At 50% of the wastewater usage there was a significant increase in cocoon production (24.24). On the basis of this research, it shows that rice mill wastewater should be either diluted to at least 50% or treated to make it suitable for irrigational purpose.

PENGEMBANGAN SISTEM TERINTEGRASI BERBASIS IOT (INTERNET OF THINGS) UNTUK MONITORING DAN KONTROL KUALITAS AIR PADA BUDIDAYA TAMBAK UDANG DARATAN

Water quality is very important for the sustainability of a shrimp farm, starting from the quantity and quality of shrimp harvested is very influential on the good quality of the pond water. The water quality in question is parameters such as water turbidity, a lot or clean of dirt in the pool, a pH value that suits your needs and ammonia content in the pond which is usually produced from shrimp manure. This research designed a water quality monitoring and control tool in shrimp ponds that is integrated automatically through an IoT-based system (Internet of Things) using the thingspeak application as a server and telegram bots as controls. Based on the results of tests that have been carried out, the tool has been able to determine the quality of water correctly. The error percentage was 0.01% for turbidity sensors, 0.05% for TDS sensors, 0.01% for pH sensors and 0.12% for ammonia gas sensors. Based on the results of direct data collection on shrimp ponds for 6 hours, the average value of water turbidity was 3.06 NTU, the lowest was 1.07 NTU and the highest was 5.99 NTU, for the average value of TDS content was 170.98 ppm, 150.00 ppm was the lowest and 204.12 ppm was the highest, for the average pH content was 7.80, the lowest was 7.50 and the highest was 8.74, and the average value of ammonia content was 0.004 ppm, 0.0007 ppm is the lowest and 0.0113 is the highest.

The Evaluation of the Quality of Local Water Company Tirta Anoa Processed Water in the Community of West Kendari District, Kendari City

Backgrounds: The government has the task of collecting, purifying and distributing clean water from water terminals via water channels, pipes or tank cars (in administrative management units with economic activities) to homes, industrial companies or other commercial uses. For this reason, Local water company has the responsibility to provide clean water for all groups of people in an area. Methods: This type of research is observational research with a descriptive approach to get an overview of the quality of Local water company Tirta Anoa's processed water. Water quality sampling was carried out in 9 sub-districts in West Kendari District, which is the sub-district with the largest population of 44,290 people. Results: The results of the pollution index analysis for TDS parameters show that river waters in the study study area at 7 monitoring points are still classified as meeting water quality standards, namely still below 1,000 mg/L. The highest TDS content was found at station 5 (AB.03 = 611 mg/L) and station 6 (AB.04 = 614 mg/L), while the lowest TDS value was at station 2 (AB.02 = 193 mg/L). And the concentration of TSS parameters is still below the quality standard, namely monitoring point 1 (AP.01 to 5 (AB.05) respectively 4.7 mg/L; 3.4 mg/L; 2.6 mg/L ; 3.7 mg/L; 3.9 mg/L; Conclusion: There is water quality (physics, chemistry, biology) from Local water company Tirta Anoa processed water which has been consumed by the community in West Kendari.

Optimizing reverse osmosis desalination from brackish waters: Predictive approach employing response surface methodology and artificial neural network models

A mathematical model frame has been developed to optimize the performance of reverse osmosis (RO) desalination in brackish waters with medium to high salt concentrations using response surface methodology (RSM) and artificial neural network (ANN), specifically catered towards efficiently operating RO desalination systems. The RSM model aims at predicting RO performance with second-order polynomials based on 15 experimental datasets. Inputs for RSM model include feed TDS concentration, feed water flow rate, and concentration-to-desalination ratio, while the outputs consider rejection, membrane flux, performance index, and specific energy consumption. The Genetic Algorithm optimized back-propagation Neural Network was employed to update network weights and biases, leading to an optimal ANN network structure of 3–10-4. A ratio of 70 % training, 15 % validation, and 15 % test data was chosen to establish an ANN model that predicts the performance of RO desalination. The ANN model demonstrated significantly higher prediction accuracy than the RSM model, with impressive correlation coefficients of 0.9936 for the performance index and 0.9932 for SEC prediction, and low RMSE of 0.85 for rejection. To maximize the performance index and minimize specific energy consumption, a two-step optimization method was further set up by applying the RSM model to initially determine optimal process conditions followed by the ANN model to enhance the accuracy of performance forecasts. Optimal process conditions were proposed for specific feed TDS scenarios, which involved setting a feed TDS concentration limit to meet drinking water standards.

Hydrogeochemical and GIS Analysis of Groundwater Quality for Drinking and Irrigation Purposes in Kuzhithuraiyar Sub-Basin, Kanniyakumari District, Tamil Nadu, India

A hydrogeochemical analysis was conducted to find the suitability of the groundwater for drinking and irrigation purposes in the Kuzhithuraiyar sub-basin, Kanniyakumari district, Tamil Nadu, India. 48 groundwater samples were collected from the different locations of the study area during both the pre- and postmonsoon periods. This study assesses the groundwater quality for drinking and irrigation purposes based on the analytical results, water quality index, Wilcox plot, and irrigation parameters such as electrical conductance, Kelly’s ratio, sodium absorption ratio values, magnesium hazards, bicarbonate, and the residual sodium carbonate index. The pH values ranged from 8.5 to 6.5, suggesting generally acceptable conditions. TDS concentrations range from 24 to 1277 mg/L, whereas EC values range from 37.50 to 1996 μS/cm. It is observed from the collected samples that the pre-monsoon water samples TDS’ values were exceeded the recommended TDS limits than postmonsoon samples. Water quality indices indicate that 50% of premonsoon samples and 48% of postmonsoon samples are suitable for drinking. In total, 10% of samples are admissible to a doubtful category before and after the monsoon, 6% are good to permissible during the monsoon, and 84% are good to permissible. Kelly’s ratio shows that 56% and 48% of samples collected during the post- and premonsoon are suitable for irrigation, respectively, whereas the remaining samples are not. Due to magnesium hazards, 40% and 44% of pre- and postmonsoon samples are not suitable for irrigation. Overall, the postmonsoon samples exceeded the permissible TDS limit (1000 mg/L) by 10% and the premonsoon samples by 6. 13% of samples obtained after the monsoon and 19% collected before the monsoon have a potential salinity greater than three, indicating that these samples are unacceptable. The sustaining water quality and mitigating possible hazards in the Kuzhithuraiyar sub-basin require continuous monitoring and focused measures.

Groundwater composition and stable isotopes as proxies to investigate paleoclimate change in permafrost thawing regions

The paleoclimate since the late Pleistocene has gained substantial attention due to its profound effects on hydrology, ecosystems, and landforms, particularly in regions experiencing permafrost thawing. Northeast China is acknowledged for exhibiting distinctive yet contentious paleoclimate, which has been elucidated through various proxies. In this case, we emphasize the significance of stable isotopes within the northern Songnen Plain as complementary proxies for paleoclimate interpretation, bolstered by radiocarbon dating. The Cretaceous sandstone confined aquifer (CSA) is designated as the reference aquifer, based on the hydrogeochemical and isotopic characteristics. The 14C results indicate that the CSA preserves groundwater from the late Pleistocene to the modern. These findings, in conjunction with isotope variations, delineate specific climate events, which are aligning with results derived from conventional proxies. The late Pleistocene-early Holocene showed a climate shift from cold to warm. The middle Holocene was warm and humid. Then the late Holocene entered the Neoglacial, which characterized by a cold climate environment. Our analysis also reveals fluctuations in the age and TDS concentration along the groundwater runoff. The paleo groundwater exhibits simultaneous lower TDS concentration, maximum δ18O depletion and minimum recharge temperature. Neither latitude nor altitude effects could account for the sufficient isotopic depletion, instead, we found that the humid climate and permafrost meltwater also contributed to the isotope depletion. Simultaneously, the paleoclimatic environment such as freeze-thaw cycles of permafrost exerts a significant influence on the groundwater. The formation of permafrost hinders groundwater recharge, while its thawing dilutes the solute content of groundwater. Additionally, the recharge gaps also potentially result from arid climate, inadequate samples, and the effects of mixing water. The study substantiates the reliability of confined aquifers in permafrost thawing regions as robust paleoclimatic archives and emphasizes the utility of stable isotopes in combination with radiocarbon dating as ideal climate proxies.

Effectiveness of cellulose acetate composite membrane with the addition of zeolite additives to reduce TDS levels in peat water using a cross-flow reactor

The need for clean water continues to increase along with population and industrial growth, which causes a water crisis. Quantitatively, peat water has the potential to be managed as a source of clean water using membrane filtration. This study aims to compare the composition of the cellulose acetate-zeolite composite membrane in reducing TDS levels in peat water using a cross-flow reactor. Cellulose acetate-zeolite composite membranes were prepared by phase inversion technique using 15 wt.% cellulose acetate (CA), with variations in zeolite concentration (5%; 10%; 15%; 20% and 25%), contact time (20, 40 and 60 minutes), the reactor pressure was 1.5 bar, and the TDS concentration in the feed water was 1,201 mg/L. Membrane characterization was done through morphological analysis using a Scanning Electron Microscope (SEM) and tensile test analysis. Membrane performance is determined through permselectivity and permeability testing. The results showed that the highest flux value was obtained on a 5% cellulose acetate-zeolite membrane at the 20th minute, namely 78.8 L/m2.hour. The best composition was obtained on a 25% cellulose acetate-zeolite membrane with a tensile strength value of 54.089 MPa and a rejection value of 92%. Morphological characterization showed that the pore size of the cellulose acetate-zeolite composite membrane decreased after use because TDS particles covered it.

Development of a 3D-printed spongy electrode design for microbial fuel cell (MFC) using gyroid lattice

Microbial fuel cell technology addresses both issues in finding new ways to clean water systems while harnessing electricity. Several studies suggest that a single large-scale MFC is proven to be inefficient and expensive. Therefore, producing small-scale MFCs is focused on investigation to provide an efficient system and cost-effective approach. This study used 3D-printed MFCs using a spongy electrode design to produce a modern approach to modifying electrode capacity in energy generation. Furthermore, the study identifies the electrical conductivity of the spongy electrode by determining the voltage generated and power density by stacked MFCs in series, parallel, and hybrid configurations. The MFCs generate a maximum voltage of 633 mV and a current of 14.22 . One way to reduce the effects of voltage reversal in the MFC system is the application of hybrid connection circuits. Parallel-series hybrid connection possesses stable voltage generation of 250−300 𝑚𝑉 with the highest current generation of 115.20 𝜇𝐴. At the same time, the Series-Parallel Connection generates the highest voltage and current of 259 mV and 30 , respectively. The spongy electrode design and hybrid connection produced a maximum power and current density of 29.30 μW⁄m2 and 279.41 μA⁄m2 obtained from a different connection of pure parallel and 28P-2S hybrid connection. Furthermore, water quality parameters were examined (pH, TDS, ORP, and COD), that the MFCs design is efficient in wastewater treatment, with a %COD removal of 95.24% efficiency, reduced ORP from +48.00 mV to -7.00 mV, and the TDS concentration from 270 ppm to 239 ppm.

Characterization of Southern Peru Hydrothermal Systems: New Perspectives for Geothermal Exploration Along the Andean Forearc

AbstractThis study provides a comprehensive characterization of various hydrothermal systems in Southern Peru ranging from the faulted Precordillera's steep topography up to the volcanic High Cordillera (&gt;4,000 m asl). The objective is to investigate thermal anomalies that may potentially serve as new geothermal resources. Our integrated approach combines: (a) geochemistry from 14 hot springs sampled throughout the Tacna region, and (b) 3D numerical modeling of coupled groundwater and heat transfer considering topography and faults embedded in homogeneous permeability. Water and gas analysis indicates that the springs located near volcanoes discharge Na‐K‐Cl waters with high temperatures (&gt;87°C), high Total Dissolved Solid concentrations (TDS &gt;3,452 mg/L), and free gases dominated by CO2 (&gt;90 vol%). Springs located along the regional faults in the Precordillera discharge Ca‐SO4 and Na‐K‐Cl waters with moderate temperatures (27–53°C), intermediate TDS concentrations (464–2,458 mg/L), radiocarbon ages between 1.4 and 7.9 kyr, and free gases dominated by N2 (&gt;95 vol%). The Aruma springs, which are located at the transition between the High and the Precordillera, display intermediate characteristics. Numerical models accurately replicate the locations and temperatures of the fault‐related springs only for permeable faults (&gt;10−14 m2), revealing the creation of 100‐km long thermal plumes along faults, locally rising up the 150°C‐isotherm to about ∼1,000 m below the surface. This approach clearly distinguishes the spring origins, which are volcanic in High Cordillera and tectonic in Precordillera. Moreover, we highlight that steep topographic gradient and permeable reverse faults in the Andean forearc may generate considerable thermal anomalies, opening perspectives for the geothermal exploration.