Metal Concentrations In Wastewater Research Articles

Bioaccumulation and Mobility of Heavy Metals in the Soil-Plant System and Health Risk Assessment of Vegetables Irrigated by Wastewater

Accumulation of heavy metals in soil and vegetables is presently a challenging environmental concern worldwide. The present study was designed to elucidate heavy metals contamination of vegetables irrigated with domestic wastewater and associated health risks. The study area comprises three zones: Kot Addu, Alipur, and Muzaffargarh. A total of 153 samples of wastewater, topsoil, and vegetables were analyzed for physicochemical parameters and concentration levels of eight metal elements (Cu, Fe, Zn, Mn, Pb, Cd, Ni, and Cr) determined through analytical procedures. The outcome of the present investigation reveals that heavy metal concentrations in wastewater, soil, and vegetables irrigated with wastewater were slightly higher than the WHO-suggested limit. The heavy metals concentration observed in vegetables irrigated with wastewater can be ranked in order of Ni > Mn > Cr > Pb > Cu > Fe > Zn > Cd. Transfer factor (TF), daily ingestion of metals (DIM), and health risk index (HRI) were calculated. Spinach exhibited higher values of transfer factor than cabbage, cauliflower, and radish, which were followed by tinda and carrot. Minimum values of HRI were observed for Cr (0.0109) in almost all of the vegetables ingested by adults and children. Cabbage exhibited higher values of HRI for Pb (4.0656) in adults, followed by cadmium (HRI = 2.993). Minimum values of HRI were calculated for Cd (0.0115; child). Cauliflower exhibited higher values of HRI (5.2768) for Pb in children. Pb, HRI values (4.5902) were observed in adults living in Kot Addu. The results exhibited similar trends of HRI in adults and children living in Muzaffargarh and Alipur.

Utilisation of waste Cu-, Mn- and Fe-loaded zeolites generated after wastewater treatment as catalysts for air treatment.

Disposal of copper, manganese and iron is particularly problematic in wastewater of metallurgical and galvanization plants, the electronics industry and agriculture. On the other hand, volatile organic compounds (VOCs), emitted from industrial processes, transportation and consumer products are the main class of air pollutants. The study revealed the potential of waste metal-loaded zeolite, generated through wastewater treatment procedures, to be utilised as an effective VOC removal catalyst for air treatment. In the first step, we have evaluated the sorption performance of natural zeolite clinoptilolite (HEU type), and synthetic zeolite 4A (LTA type) for the simultaneous removal of Cu2+, Mn2+ and Fe3+ species from aqueous solution. By a detailed sorption study, we determined the optimum sorption conditions and maximum metal concentrations in wastewater that can be after treatment disposed of in rivers or municipal plants. The efficiency of both zeolites for metal immobilization was demonstrated for concentrations up to 5mg metals/1g zeolite. These waste Cu-, Mn- and Fe-loaded zeolites were thermally treated at 540°C before the second step, where we evaluated their catalytic performance in removing VOC. The thermally treated waste Cu-, Mn- and Fe-loaded natural zeolite clinoptilolite showed good catalytic performance in total toluene oxidation as a model VOC (conversion rate up to 96% at 510°C) and cycling stability (less than 15% drop in conversion rate in 4h). In contrast, this is not the case for thermally treated waste Cu-, Mn- and Fe-loaded synthetic zeolite 4A.

Assessment of Physicochemical and Metal Concentrations in Wastewater from the Industrial Zone of Cotonou Benin

The present study aimed to assess the physico-chemical quality of wastewater(s) in order to better control the flow of various pollutants generated by the industries from the industrial zone of Cotonou. Water samples were collected in triplicate in each collector and analyzed for their nutrient and metal content (Cu2+, Fe2+, Cd2+, Al3+ and Pb2+) and chemical oxygen demand (COD) and a five-day biochemical oxygen demand (BOD5) were carried out by spectrophotometry. The results revealed highly mineralized waters, indicated by average pH (6.97± 0.34), dissolved oxygen (5.16 ± 0.29 mg/L), electrical conductivity (2280.58 ± 263.97 µS/cm) and total dissolved solids (1076.04 ± 51.01 mg/L). The values of COD (482.05± 1.18 mg/L) and BOD5 (291.67 ±2.19 mg/L) were very high, exceeding the standard for industrial wastewater discharge in Benin respectively by 5 and 11 which is indicative of the presence of very poor biodegradable materials coming essentially from industrial discharge in the study area. The concentration of Cd2+, Pb2+ and nutrient salts indicative of eutrophication were relatively low in the collectors. However, the concentration of Al3+ (2.65±0.03 mg/L) and Cu2+ (10.20 ± 0.14 mg/L) were very high with the later cation being four times higher than the wastewater standard in Benin (2.5 mg/L) for the most heavily loaded collectors. In conclusion, the results of this study provide useful insights for implementation of purification system and efficient management of wastewater from industries.

Wastewater Treatment by Azolla: A review

Water is vital for humans and other living things, but water pollution has become a significant issue today. Various anthropogenic agricultural, industrial, and home activities produce multiple organic and inorganic substances dissolved or suspended in water. The goal of wastewater treatment is thus twofold: to reduce water pollution while also maintaining the water supply to demand. It is based on the three 3 Rs: reduce, reuse, and recycle. However, many of the methods used are ineffective or expensive. As a result, water purification is a matter of great interest. Eco-friendly approaches are essential among the new technologies and techniques tested in wastewater treatment. Aquatic macrophytes treat water by accumulating harmful metals and nutrients. Like water filters, a variety of aquatic floats can be suggested. Azolla is one among them, and it has been used for decades. Researchers have discovered that Azolla can reduce Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), nitrogen, phosphorus, and heavy metal concentrations in wastewater; therefore, it can be utilized for wastewater treatment. Azolla also produces a lot of biomasses in wastewater. The use of Azolla in reducing eutrophication in lakes and streams and other benefits is discussed in this study. According to the literature, Azolla has a high growth rate, with a doubling date of 2-4 days. Azolla's cell wall is composed of pectin, which has a high affinity for the adsorption of organic substances. Azolla serves as a "biofilter" during wastewater treatment in this way.

ПОРІВНЯЛЬНА ХАРАКТЕРИСТИКА ЕФЕКТИВНОСТІ ЕЛЕКТРОХІМІЧНИХ МЕТОДІВ ДОСЛІДЖЕННЯ ВМІСТУ ВАЖКИХ МЕТАЛІВ У СТІЧНИХ ВОДАХ

Сompare the various modern electrochemical research methods effectiveness used to determine the heavy metals concentration in waste water, based on the literature data. Methodology. Analysis of literature data on the possibilities, advantages and disadvantages of voltammetric, potentiometric, coulometric and conductometric methods for the heavy metals content studying in waste water. Findings. The electrochemical methods are the most common methods for analyzing the composition of waste water. Among their advantages, it should be noted high selectivity, low concentration registration limit (up to 10-10 M for stripping voltammetric methods), simplicity in execution, absence of preliminary long-term samples preparation for analysis, the ability to microvolumes measure without samples destroying and automation of the process for continuous metals concentrations determination in waste water treatment, relatively inexpensive equipment, the ability to determine the concentration of several metal ions in a mixture. Originality. The studies have shown that most often the concentration of heavy metals in waste water determine with the using of the different modifications of voltammetric research methods (polarography and varieties of stripping voltammetry) and potentiometric research methods in particular with highly sensitive and specific ion-selective indicator electrodes. Practical value. The theoretical material on modern electrochemical methods for the heavy metal ions content determining in waste water is generalized.

Fertilization with Municipal Wastewater Phosphorus Adsorbed to Alginate Beads: Results from a Pot Experiment with Italian Ryegrass

The global increase in the demand for fertilizers and thus phosphorus (P) contributes to the depletion of P reserves and the need to recycle this element. This paper presents the results of a pilot-scale experiment on the possibility of using a fertilizer preparation containing alginate, Fe and P (AFP) obtained in the process of P adsorption from sludge water on a hydrogel alginate adsorbent cross-linked with iron (III) ions. The influence of AFP on the growth of a model plant of the Italian ryegrass (Lolium perenne cv. Turtetra) was examined in comparison with differentiated mineral fertilization (MF) under the conditions of a pot experiment. The two fertilizers produced similar crop yields of the tested plant and had similar plant and soil macro- and micro-elements, except for the content of Fe and Cu in ryegrass, which was significantly higher with AFP fertilization. Further research on the use of the proposed sorbent for large-scale P recycling in an uncontrolled field environment should include acceptable limits for multivalent metal concentrations in wastewater, the mechanical/thermal stability, and the effectiveness of AFP under field conditions and a cost competitiveness. AFP has the potential to compete with mineral fertilizers for P fertilization, and this technology is in line with the EU circular economy vision.

Uptake and mobilization of heavy metals through phytoremediation process from native plants species growing on complex pollutants: Antioxidant enzymes and photosynthetic pigments response

The aim of this work was to study the metal removal efficiency of Rumex dentatus, Ranunculus sceleratus , and Cammelina benghalensis which thrive on wastewater containing complex co-pollutants. Physico-chemical characteristic of wastewater showed high levels of biological oxygen demand (7136 mg kg −1 ), chemical oxygen demand (26324 mg kg −1 ), electric conductivity (1531 μ S cm −1 ), along with metals (mg kg −1 ) such as Fe (124.65 mg kg −1 ), Zn (56.33 mg kg −1 ), Cu (6.34 mg kg −1 ), Cd (9.02 mg kg −1 ), Mn (23.64 mg kg −1 ), Ni (6.04 mg kg −1 ), Pb (1.20 mg kg −1 ), Hg (1.08 mg kg −1 ), Cr (1.31 mg kg −1 ) and As (1.43 mg kg −1 ) along with complex co-pollutants. All three plants reduced more than <50% of all physicochemical parameters and metal concentrations in wastewater. The chlorophyll (Ch-a, Chl-b) contents was highest in Rumex dentatus (5.03–6.74 mg g −1 fw), followed by Ranunculus sceleratus (5.69.00–8.03 mg g −1 fw), and Cammelina benghalensis (4.65–7.08 mg g −1 fw), which showed the potentiality of plants. All the plants showed antioxidant activity (U/mL), i.e., superoxide dismutase (SOD), estimate peroxidase (POD), ascorbate peroxidase (APX), catalase (CAT), and hydrogen peroxidase (H 2 O 2 ), bioaccumulation factor, and translocation factor, which demonstrated these plants’ high translocation abilities. The results offered evidence to support the potential of using native plants for phytoremediation as a novel green process to be integrated into the treatment and management of hazardous industrial wastewater.

TiO2/rectorite-trapped cellulose composite nanofibrous mats for multiple heavy metal adsorption

The anthropogenic release of highly toxic heavy metals into the environment presents a huge challenge for ecosystems and human society. Recoverable and efficient adsorption materials could be obtained by trapping inorganic adsorbents (e.g., TiO2 nanoparticles and rectorite (REC)), in a natural polymer matrix. In this study, a series of cellulose-TiO2/REC composite nanofibrous mats were fabricated via electrospinning. The interactions between inorganic adsorbents and cellulose molecules improved the thermal stability, surface area, tensile strength and adsorption capacity of the mats. We focused on the adsorption of Pb2+, Cu2+ and Cd2+ from acidic solutions onto cellulose-TiO2/REC composite nanofibrous mats in multiple systems because the magnitudes of heavy metal concentrations in wastewater typically varied. The maximum total adsorption capacity of 69.81 mg/g was obtained by Cellulose-TiO2/REC2:1 nanofibrous mats. The composite nanofibrous mats successfully trapped TiO2 nanoparticles, and the obtained cellulose-TiO2/REC nanofibrous mats could be used to remove heavy metals from acidic wastewater.

Determination of heavy metals concentration in waste water of Warri Refining and Petrochemicals Company (WRPC)

Waste water from some industries contain high levels of contaminant such as colloid, suspended and dissolved minerals. Heavy metals have negative impact on all forms of life in the environment. Crude oil refining makes use of large volume of water, whence generate large quantities of waste water which must comply with stringent environmental guidelines. To this end, several treatment methods have been explored in order to keep contaminants levels within limits. This study investigated the presence of heavy metals in discharged waste water effluents from the premises of Warri Refining and Petrochemical Company LTD into the Ubeji creek. The analysis was carried out using the Flame Atomic Adsorption Spectrometry method. Standard solution used for calibration were prepared for the five heavy metals analysed. Results showed average concentrations of chromium was within the acceptable limit. The overall results show that effluent water from WRPC has concentrations of heavy metals that is within the prescribed acceptable limits for discharge into the environment.

Pollution Load Index (PLI) of field irrigated with wastewater of Mawaiya Drain in Naini suburbs of Allahabad District

Wastewater irrigation is practiced in outskirts of several cities of India. Enhanced growth and productivity of crops possess threat of heavy metal accumulation while irrigated with wastewater. Assessment of heavy metal accumulation in soil flooded with wastewater of Mawaiya drain in Naini region of Allahabad district, using parameter of contamination factor and pollution load index (PLI). Samples of soil were taken from the fields irrigated with wastewater and analyzed for heavy metals by using Atomic Absorption Spectroscopy (AAS). The maximum accumulation of heavy metal was observed for iron in soil. Heavy metal contamination is soil was assessed by estimation of contamination factor which was observed for Cu (0.7858), Fe (296.1864), Zn (0.4304), Pb (1.1661) and Ni (1.8912). Pollution load index (PLI) used for assessment of soil contamination and observed that maximum contamination (PLI, 74.31) was in water stressed conditions of summer. Heavy metals concentration in wastewater and accumulation in soil found within WHO limits in present study which may increase if unmanaged wastewater flooding continued.

A Study on Heavy Metal Concentrations in Waste Water Produced in the Casting Pickling Process at Dental Technical Laboratories

A Study on Heavy Metal Concentrations in Waste Water Produced in the Casting Pickling Process at Dental Technical Laboratories

Influence of using treated wastewater with moringa seeds and chitosan on wheat growth and uptake of nutrients and heavy

The present study was carried out to treat wastewater and investigate its impact on wheat growth, uptake of nutrients and heavy metals. To achieve this task, two experiments were conducted at the Faculty of Agriculture, Al-Azhar University-Cairo-Egypt, during winter season of 2014. The 1st (lab experiment) was for treatment wastewater by using moringa seeds and chitosan with different doses (0.5, 1 and 2g/l as powder and 1, 2 and 3 % as extract). The 2nd (pot experiment) was carried out to investigate the effect of the previously treated wastewater on wheat growth, uptake of nutrients and heavy metals. The main results from the first experiment showed thatheavy metals concentration in wastewater decreased significantly by increasing the addition of the added materials. Moringa seeds and chitosan as powders were more effective than its extracts. Results from the second experiment indicated that there was an increase in both fresh and dry weight of wheat plant irrigated with treated wastewater compared with control. Also, the highest values were observed at the highest dose of chitosan extract (3%). On the other hand, the uptake of N, P and K by wheat plants increased significantly by increasing the added materials. Moreover, the heavy metals uptake by wheat plant (µg/plant) was decreased by addition of the treated materials.

Metal uptake of tomato and alfalfa plants as affected by water source, salinity, and Cd and Zn levels under greenhouse conditions.

Irrigation with wastewater is a promising option to improve crop yields and to reduce pressure on freshwater sources. However, heavy metal concentrations in wastewater may cause health concerns. A greenhouse pot experiment was conducted in order to determine cadmium (Cd) and zinc (Zn) concentrations in sandy soil and plant tissues of tomato (Lycopersicon esculentum L.) and alfalfa (Medicago sativa L.). A 2 × 2 × 4 × 2 factorial treatment arrangement was utilized. Two water sources, fresh (FW) or treated wastewater (TWW), at two salinity levels (1 and 3 dS m(-1)) containing different levels of Cd and Zn were used. Samples were collected after a 90-day growth period. It was observed that the growth of both plants was depressed at the highest metal level (L3). Metal accumulation in plant parts increased with the increase of metal concentration and salinity in irrigation water. At low salinity, water source was the main factor which controlled metal accumulation, whereas, at high salinity, chloride appeared to be the principal factor controlling metal uptake regardless of water source. Metal translocation from roots to shoots increased in TWW-irrigated plants, even in the controls. Tomatoes accumulated Cd up to and above critical levels safe for human consumption, even though Cd concentration in irrigation water did not exceed the current recommended values. Therefore, food production in sandy soils may well pose a health hazard when irrigated with TWW containing heavy metals. Complexation with dissolved organic compounds (DOC) in TWW may be to be the principal factor responsible for increased metal uptake and transfer at low salinity, thereby increasing the risk of heavy metal contamination of food and forage crops.

Behavior of metals in a combined wastewater collection system in Ostrava, Czech Republic.

In combined wastewater collection systems, the concentrations of metals and the form of metal occurrence (dissolved form and bonding of metals to total suspended solids) influence the efficiency of capturing metals into sludge in wastewater treatment plants. The variability of metal concentrations was determined for 12 sampling sites during dry weather periods (DWP) and wet weather periods (WWP). Wastewater during DWP contain in dissolved form 77% of cadmium, 75% of nickel, 66% of arsenic, 57% of manganese and 50% of zinc and copper. Other metals are preferably bound to suspended particulates: 65% of chromium, iron, vanadium, mercury and 91% of lead. Comparison of metal concentrations in wastewater during DWP and WWP can be used to determine non-point source contributions. During WWP, metal concentrations increase by 24 to 25% for cadmium and zinc, 22% for nickel and 18% for copper. Urine and feces are responsible for a very small portion (<15%) of the total content of metals. Households are the main source of cadmium and copper (64% of total concentrations of these metals in wastewater).

Analysis of Heavy Metals Concentration in Wastewater along Highways in Croatia

In this paper we have analysed concetrations of heavy metals (lead, copper, nickel, zink, mercury, cadmium, and chromium) in wastewater along highways in Croatia. We have used standard statistical methods: analysis of variance, Kruskal-Wallis test and principal analysis. Analysis of variance and Kruskal-Wallis test were used to detect factors that influence the concentration of lead, copper, nickel, and zink in wastewater. We have investigated the influence of the highway sampling location, the side of a highway, and the influence of the season of the year. Principal components were used to identify groups of elements with similar characteristics in wastewater.

Heavy metals uptake by vegetables growing in sewage irrigated soil: relationship with heavy metal fractionation in soil

Concentrations of the heavy metals Cd, Ni, Cr, Zn, Mn, Co and Cu in soils and vegetable samples (i.e. green chili and gourd) taken from six vegetable fields in the vicinity of Lahore, Pakistan were measured. These soils have been irrigated for a long time with untreated sewage effluents. A control site was selected that has history of fresh canal water irrigation. The sequential extraction procedure developed by Tessier was adopted to demarcate five metal fractions: exchangeable, acid soluble, reducible, oxidizable and residual. The extractants and digests were analysed by atomic absorption spectrometry. The fractionation procedure showed that all the metals were dominant (>50%) in the residual phase in control as well as in waste waster irrigated soils. The concentrations of all the metals in edible parts of the vegetables collected from wastewater irrigated soils, were above critical levels. The total metal concentrations in wastewater irrigated soils followed the order Mn> Co> Zn> Cr> Ni> Cu> Cd, while in control soils the ord er was Mn> Zn> Ni> Co> Cr> Cu> Cd. In order to understand the uptake of metals from soil to vegetables, correlation analyses were performed between metal concentrations in different fractions of soil and their concentrations in vegetables. Correlation analysis was performed at 95% and 99% confidence level. The meaningful significant negative correlation was observed between CdF5–Cdchili,CrTotal–Crgourd,MnF5–MnChili,Gourd, CoF5, Total–Cochili, CuTotal–CuChili which indicate the non availability of total content and residual fraction to studied vegetables. The positive correlation was observed between CdFl-CdChiU, CdFl–Cdgourd, NiFi, F3–NiGourd, CrFi, F3, F4–CrChiU, CrF2–CrGourd, ZnFi, F2–ZnGourd, MnF3–MnChili, MnFi–MnGourd, CoF2–CoChili, CuFi–CuChili. The positive correlation, especially for the first (exchangeable) second (acid soluble) and for the third (reducible) extraction steps, was obtained which indicate the bioavailability of these metal fractions to plant.

Enhanced Removal of Heavy Metals in Primary Treatment Using Coagulation and Flocculation

The goal of this study was to determine the removal efficiencies of chromium, copper, lead, nickel, and zinc from raw wastewater by chemically enhanced primary treatment (CEPT) and to attain a total suspended solids removal goal of 80%. Operating parameters and chemical doses were optimized by bench-scale tests. Locally obtained raw wastewater samples were spiked with heavy metal solutions to obtain representative concentrations of metals in wastewater. Jar tests were conducted to compare the metals removal efficiencies of the chemical treatment options using ferric chloride, alum, and anionic polymer. The results obtained were compared with those from other studies. It was concluded that CEPT using ferric chloride and anionic polymer is more effective than CEPT using alum for metals removal. The CEPT dosing of 40 mg/L ferric chloride and 0.5 mg/L polymer enhanced heavy metals removal efficiencies by over 200% for chromium, copper, zinc, and nickel and 475% for lead, compared with traditional primary treatment. Efficient metals capture during CEPT can result in increased allowable headworks loadings or lower metal levels in the outfall.

A Preliminary Investigation on Boron and Metal Concentrations of the Main Drainage Channel in Konya-turkey

In this work, the wastewaters and sediments of the main drainage channel in Konya (Turkey) were collected from three different sampling points and analyzed for metals, including iron, chromium, copper, lead, zinc and nickel by using inductively coupled plasma-atomic emission spectrometry (ICP-AES). It was found that for all sampling points sediment samples show a decrease in concentrations in the order Fe ≫ Zn > Cr > Ni > Cu > Pb. For all sampling points, heavy metal concentrations in wastewater did not exceed the maximum admissible discharge levels regulated by the Institute of Turkish Standards. However, it was found that boron concentration of wastewaters exceed the safe level for irrigation of farmland.

Profitability of in-plant modifications in pollution control

Abstract This case study was developed in view of setting up a demonstration project on “revealing the profitability of clean technology in small-scale electroplating unit”. The research was conducted in a small-scale electroplating shop located in Bangkok. A set of simple in-plant control measures such as dragout recovery, spray rinsing technique and rinse water agitation were implemented. Quantitative data, obtained from the monitoring of wastewater before and after process modifications, have indicated a substantial reduction both in quantity and strength of wastewater generated. Water consumption was reduced by approx. 35% of total rinsing water, which is 19% of total process water consumption. Average metal concentrations in wastewater was reduced 73% for Cr-, 71% for Ni- and 54% for Cu-plating rinse water.

Metal removal by wetland mesocosms subjected to different hydroperiods

Scirpus californicus (giant bulrush) wetland mesocosms were subjected to four hydroperiods (pulsed-discharge regimes). The most frequently pulsed treatment (twice per day) was the most efficient at removing metals from synthetic wastewater. This was attributed to the formation of iron oxyhydroxides, which complex with the metals. The continuously flooded treatment had slightly lower removal rates. After a year of metal additions, mean removal efficiencies were 75–78% for cadmium, chromium, and zinc, 84% for lead, and 55% for mickel. Most of the metals were retained in the soil. The fine roots accumulated roughly 35% of the added cadmium, 6% of the copper, and 13% of the zinc. The shoots, rhizomes, and coarse roots each accumulated about 1% or less of the added metals. Indications are that wetland treatment, especially with hydroperiod manipulation, can reduce metal concentrations in wastewater and, therefore, in downstream ecosystems.