Domestic Water Treatment Research Articles

Assessment of carbon footprint of potable water production: A case from Bangladesh

Carbon footprint (CF), a measure of greenhouse gas (GHG) emissions, is currently a global concern because of its significant effects on climate change. Understanding GHG emissions from potable water production is important because water treatment and distribution consume much energy while emitting a significant amount of GHG. With economic and population growth, water demand has increased, resulting in higher GHG emissions. This study aims to assess the CF of potable water production in Bangladesh, focusing on the country’s economic capital, Chattogram. This study estimates and compares the CF of the treatment, distribution, and consumption phases. It also estimates the CF of different water treatment plants (WTPs) during the treatment phase. WTPs use electricity for a full-scale operation, during which approximately 4.5 million m3 of raw water of varying turbidity is treated. This study calculates a country-specific GHG emission factor for Bangladesh’s electricity generation method as different sources produce different quantities of GHGs. This study also considers the energy consumed to distribute water from the WTPs to household rooftop tanks in the distribution phase. For the consumption phase, the study considers the energy consumption for domestic water treatment, which involves boiling of a portion of treated water for drinking purposes. The study estimates that approximately 0.18, 0.27, and 17.52 kg CO2 equivalent (CO2-eq) are emitted in the treatment, distribution, and consumption phases, respectively, for the production of 1 m3 of water. Boiling at the consumption phase alone generates 97.48% of the total CF. The daily CFs for surface water and groundwater use in 2017 were 16,387.78 and 34,092.08 kg CO2-eq, respectively; those in 2022 were 83,769.25 and 2130.97 kg CO2-eq, respectively. The outcome of this study will assist stakeholders and policymakers in the progress of SDG-13 and in effective planning and operational decision making for sustainable water systems.

Pepper mild mottle virus as an effective tool in microbial source tracking for deficient domestic on-site water treatment systems

Pollution from domestic on-site wastewater treatment systems (OWTS) is a significant contaminant pressure in many rural catchments. However, due to their design, and dispersed proliferation, it is difficult to assess their impact. Water testing methodologies employ bacterial culturing methods and chemical analysis which may lose resolution and/or specificity being confounded by diffuse agricultural sources within a rural environment. In this study, we successfully assessed the applicability of Pepper Mild Mottle Virus (PMMoV) as a human faecal source tracker for deficient on-site wastewater treatment systems. The transport of PMMoV was first studied in the effluent of a 30 cm deep soil column which was dosed for 510 days with primary influent from a conventional septic system. The removal of PMMoV through the 30 cm deep soil column was quantified with a 5-day seeding trial employing primary influent mixed with PMMoV sourced from Tabasco pepper product ®. The trial was then carried out at field scale with the seeding solution dosed into an operational percolation trench receiving septic tank effluent which had been instrumented for porewater sampling. Samples were taken at depths of 10 cm, 30 cm, and 50 cm across the length of the trench at distances of 1 m, 7.5 m, and 17.5 m from the inlet of the trench. PMMoV was detected on all days of the trial, with a peak concentration of 1 × 106 found at the rear of the trench on day 2 of the seeding trial. Finally, to assess the effectiveness of PPMoV as a microbial source tracking tool from a water receptor perspective, three rural catchments with high densities of OWTSs were sampled and analysed for hourly variations in biological parameters which included total coliforms, Escherichia coli, PMMoV, and chemical parameters total organic carbon, total nitrogen, and total carbon. PMMoV was detected in all river samples over a 24-hour period, thereby indicating its suitability as a tracer of human wastewater effluent in such environments with multiple diffuse sources.

Immobilized enzymatic membrane surfaces for biocatalytic organics removal and fouling resistance

This research reported on the immobilization of environmentally friendly enzymes, such as horseradish peroxidase (HRP) and laccase (L), along with the hydrophilic zwitterionic compound l-DOPA on nano-filtration (NF) membranes. This approach introduced biocatalytic membranes, leveraging combined effects between membranes and enzymes. The aim was to systematically assess the efficacy of the enzymatic modified membrane (HRP-NF) in degrading colors in the wastewater, as well as enhancing the membrane resistance toward organic fouling. The enzymatic immobilized membrane demonstrated 96.3 ± 1.8% to 96.6 ± 1.9% removal of colors, and 65.2 ± 1.3% to 67.2 ± 1.3% removal of TOC. This result was underpinned by the insights obtained from the radical scavenger coumarin, which was employed to trap and confirm the formation of PRs through the reaction of enzymes and H2O2. Furthermore, membranes modified with enzymes exhibited significantly improved antifouling properties. The HRP-NF membrane experienced an 8% decline in flux, while the co-immobilized HRP-L-NF membrane demonstrated as low as 6% flux decline, contributed by the synergistic effect of increased hydrophilicity and biocatalytic effects. These findings confirmed that the immobilized enzymatic surface has added function of degrading contaminants in addition to separation function of nanofiltration membrane. These l-DOPA-immobilized enzymatic membranes offered a promising hybrid biocatalytic membrane to eliminate dyes and mitigate membrane fouling, which can be applied in many industrial and domestic water and wastewater treatment.

Magnetic treatment of irrigation water and its effect on French bean (Phaseolus vulgaris)

Abstract Magnetic water treatment (magnetic treatment device (MTD)) has long been a contentious procedure for domestic water treatment. This study examines the pros and cons of using different water types with and without a magnetic field treatment for growing French bean crop irrigation. The MTD used in this experiment works by ionizing the dissolved solid using a cathode and anode, electrolysing water using a dynamic pulse current at 50 kHz, and energizing the cations using a 7,000 Gauss magnet. The MTD of normal, waste and saline water enhanced the yield by 12.7, 16.9, and 20.07% over their respective control plots. Contrarily, seed protein (22.52 g/100 g), vitamin A (687.09 IU), potassium (212.44 mg/100 g), vitamin K (14.32 mg/100 g), and calcium (39.93 mg/100 g) reached their peak values when French bean plants were irrigated by magnetically treated wastewater. Na concentration in pods was significantly reduced when 3,000 mg/L of magnetically treated saline water was used to irrigate French bean plants. The MTD of irrigation water has also improved N and K desorption from colloidal soil complexes, which significantly helped make these two elements easily available to the plants and promoting better plant growth and yield. Overall, using the MTD, the overall characteristics of French bean were improved.

Yttrium-modified drinking water treatment residue for efficient phosphorus removal: efficacy, mechanism, and reproducibility.

The excessive presence of phosphate can cause eutrophication in water bodies. Yttrium has an extremely high affinity for phosphorus and is capable of forming stable complexes at low concentrations. Moreover, limitations in the resourcefulness of drinking water treatment residues were observed. In this study, a highly efficient phosphorus removal adsorbent (RJDWTR@Y) was prepared by calcination-alkali leaching-yttrium-loaded composite modification employing domestic drinking water treatment residue as raw material. And the effects of multiple factors on phosphate adsorption by RJDWTR@Y were examined. The results illustrated that the maximum adsorption capacity of the RJDWTR@Y for phosphate was 319.76 mg/g, with the chemical reaction of the multilayer as the predominant adsorption process. The adsorption mechanism is electrostatic gravitational force and the inner sphere complexation effect. RJDWTR@Y was effective against interference even at high concentrations of the coexisting anion. After five cycles, the desorption efficiency of phosphate was 75.11%. Filling the fixed bed with the material can efficiently remove phosphorus from the flowing liquid. The synthesis of RJDWTR@Y and the results of the study indicated that it has good application prospects. In addition to efficiently removing phosphorus, it can also recycle waste and achieve sustainability.

Spatial-temporal variation characteristics and coupling coordination of the “water resources – water environment – water ecology” carrying capacity in the Three Gorges Reservoir Area

The coordinated control and management of water resources, the water environment, and water ecology are essential for optimizing the management of water resources, improving the water environment, rehabilitating water ecosystems, and achieving sustainable development. Most studies conducted to investigate the water carrying capacity have focused primarily on water resources or water environment. However, it is challenging to conduct such research in areas where the interactions between water resources, the environment, and ecology are intricate. In this study, an evaluation indicator system for the water resources - water environment - water ecology carrying capacity (WCC) was constructed, and a coupling coordination model and GeoDetector were employed to systematically analyze the coupling coordination indices (CCI) among the water resource carrying capacity (WRECC), water environment carrying capacity (WENCC), and water ecology carrying capacity (WECCC), as well as the main influencing factors in the Three Gorges Reservoir Area (TGRA) from 2005 to 2018. The results showed that the numbers of counties and districts with a high CCI class gradually increased over this period. The percentage of Class V fluctuated from 0% to 7.7%, and the stability of the water system steadily increased. Spatially, the overall distribution pattern gradually increased from southwest to northeast, and both the single and interactive effects of anthropogenic factors on water systems gradually increased. The CCI was predominantly affected by factors such as the amount of surface water resources per capita, indices of water conservation, forest coverage, discharge of domestic sewage per capita, and water replenishment of the ecosystem. These results show that coordination between the WCC components should be strengthened to further improve water use and domestic water treatment efficiency. To achieve superior-class, effective, and environmentally friendly scientific governance, the productivity of water resources should be increased in areas where the disparity between water availability and the demand for socioeconomic development is severe, and sewage treatment processes should be closely regulated. It is also important to combine resource development and utilization with water ecological protection and management.

Water Safety Plan, Monochloramine Disinfection and Extensive Environmental Sampling Effectively Control Legionella and Other Waterborne Pathogens in Nosocomial Settings: The Ten-Year Experience of an Italian Hospital.

Legionella contamination control is crucial in healthcare settings where patients suffer an increased risk of disease and fatal outcome. To ensure an effective management of this health hazard, the accurate application of a hospital-specific Water Safety Plan (WSP), the choice of a suitable water disinfection system and an extensive monitoring program are required. Here, the ten-year experience of an Italian hospital is reported: since its commissioning, Legionellosis risk management has been entrusted to a multi-disciplinary Working Group, applying the principles of the World Health Organization's WSP. The disinfection strategy to prevent Legionella and other waterborne pathogens relies on the treatment of domestic hot water with a system ensuring the in situ production and dosage of monochloramine. An average of 250 samples/year were collected and analyzed to allow an accurate assessment of the microbiological status of water network. With the aim of increasing the monitoring sensitivity, in addition to the standard culture method, an optimized MALDI-ToF MS-based strategy was applied, allowing the identification of Legionella species and other relevant opportunistic pathogens. Data collected so far confirmed the effectiveness of this multidisciplinary approach: the fraction of positive samples never overcame 1% on a yearly basis and Legionnaires' Disease cases never occurred.

Chemical analysis and filtration efficiency of ceramic point-of-use water filters

Ceramic water filters (CWFs) are globally employed as a point-of-use water treatment technology. Although, there are no standards to regulate the use of these CWFs in developing countries, they are gaining acceptability for domestic water treatment. This study sought to assess and compare the efficiency of commercially available types of CWFs and to propose a consumer selection guide for the purchase and use of CWFs. The CWFs selected for the study were, Ball filter with activated carbon (BF + AC), Candle filter (CF), and Pot filter (PFcs) coated with colloidal silver. The elemental and mineral oxide composition of the selected CWFs were analysed with x-ray fluorescence method. Furthermore, the raw unfiltered water (from three different common sources), and the filtrates obtained with the CWFs were analysed for their physicochemical, metal ion removability, and microbial correction. The x-ray fluorescence analysis indicated that Al2O3 and SiO2 were the major mineral oxide compositions of the selected CWFs. These metal oxides were present in varying concentrations. The CWFs showed turbidity reduction of 74.28–99.40%, Mn and Fe reduction of 54.04–98.48% and 48.82–97.50% respectively. In addition, the total coliform reduction by the selected CWFs ranged from 2.31 to 76.97%. It was therefore observed from the results that, the efficiency of commercially available CWFs varied in the order BF + AC > CF > PFcs. BF + AC was the most efficient in both physicochemical and microbial correction of all water sources. CWF selection guide for consumers based on different sources of water which considered the physicochemical parameters, biological parameters and Water Quality Index was discussed. This has an implication for regulation and standardization of CWFs.

Stabilization Tank with Respect to Detention Time for Grey Water Treatment

Abstract: Characterization and treatment of grey water; options for (re)use. PhD thesis, Wageningen University, The Netherlands. Addressing the issues of water shortage and appropriate sanitation in Jordan, domestic grey water treatment receives growing interest. Grey water comprises the domestic wastewater flows excluding waters associated with the toilet. The topics of concern for grey water are its characteristics, treatment and potentials for use after treatment. The target of this thesis is to develop a concept for treating grey water on-site for agricultural usage, thus sustaining a recycling process of grey water in Jordan. A review was made regarding the currently available grey water treatment technologies. In addition, grey water was quantitatively and qualitatively characterized, and then grey water reuse requirements including treatment, were analyzed. Biodegradability and biodegradation rates of the grey water were investigated for selecting appropriate design and operation criteria of the treatment technology to be developed. A low-tech semi-technical scale treatment system was tested to treat grey water discharges from a dormitory at the Jordan University campus. The treatment system was evaluated on obtained removal efficiencies and conformity of the effluent to the guidelines for the use of reclaimed water for irrigation in Jordan. Finally, the objectives, approaches and the results of each chapter are summarized, and then both the results and the potential of applying decentralized sanitation and reuse (DeSaR) concepts in Jordan are discussed. Results show that storage and treatment are prerequisites for any type of grey water use. Grey water is aerobically and anaerobically biodegradable but the conversion rates are low. The core of the treatment concept consists of an integrated storage and anaerobic treatment unit, fed with a natural influent flow pattern, in a down-flow mode, up to a one day operational cycle, i.e. a variable HRT ≤ 24 hours. The second step consists of an aerobic post-treatment, mechanically aerated in a down-flow mode and a one day operational cycle, i.e. 24 hours HRT. Both units need insulation in the winter period. The final effluent, stable in winter and summer, meets the Jordanian

The Quality of Kiserian Slaughterhouses’ Effluent and Its Implication on Kiserian Dam Water in Kajiado County, Kenya

Purpose: Wastewater from abattoirs, municipal, agricultural and industrial effluents is a major source of environmental pollution as they consume large amounts of fresh water for meat processing and hygienic purposes. The main objective of the study was to assess the quality of the effluent from Keekonyokie and Kiserian slaughterhouses and its effect on the quality of water in Kiserian dam.
 Methodology: The parameters measured were pH, total suspended solids, total nitrogen, total phosphorous, dissolved oxygen and fecal coliforms (E. coli). Samples were collected from 4 sampling sites three times a week for three months. SPSS (ANOVA) for their significant differences. One-sample t-test used to compare the parameter means with NEMA 2006 standards. Pearson Correlation used for correlation among the parameters.
 Findings: The mean fecal coliforms 2215.206 mg/l, Phosphorous 47.379 mg/l, Nitrates 36.71 mg/l, TSS 387.57 mg/l which were above the standards of NEMA 2006 of nil, 2, 2 and 30 mg/l respectively while DO was 8.58 mg/l and pH 6.86-7.0 both of which were below the NEMA 2006 standards of 30 mg/l and 6.5-8.5. The results of all parameters were significantly different among the sites (p=0.00). There was significant difference between the parameters and the NEMA 2006. ANOVA results on parameters showed the all coliforms increased with increase in rainfall with the highest levels in September with a mean 18662.7 mg/l and in July with the lowest of 12962.5 mg/l.
 Unique Contribution to Theory, Practice and Policy: The study can be used by slaughterhouses developers and management on slaughterhouse wastewater treatment. To be used by slaughterhouses licensing authorities on SWW requirements before licensing. To be used by Public Health Department for disease surveillances and Water Regulatory Management Authority on domestic water treatment.

Literature Review on Effect of Sludge Age on Microbial Community Structure in HMBR

The composite membrane biological treatment process has the characteristics of high quality effluent and low membrane pollution, which is widely used in domestic and international water treatment industry. Based on the review of the basic research on membrane fouling mechanism and the comparison of the research results of MBR at home and abroad, from the perspective of microbial ecology, based on the new generation of environmental microbial analysis technology of high-throughput sequencing, this paper expounds the microbial ecological mechanism that sludge age changes the content of microbial metabolites and membrane fouling process by affecting the microbial community structure and physiological characteristics.

Research on Autopsy Results of over 10 Year Old Low Pressure Hollow Fiber Membrane from Domestic Water Treatment Plant

Objectives : In this study, membrane autopsy was performed for a parallel arrayed low-pressure membrane (microfiltration) filtration process that is actually applied to water treatment, to check out whether there are differences in the degree of membrane fouling due to the uneven flow rate into each module. Also, membrane foulants were evaluated quantitatively.Methods : In this study, autopsy was performed for over 10 year old membranes used for drinking water purification. In this way, the outer casings of membrane modules at different positions were disassembled and visually observed. In addition, In addition, the size of the pores and the porosity were investigated by taking a SEM (Scanning Electron Microscope) photograph for the new and the used membrane module fiber samples in different positions from the header pipe. The used membrane foulants were classified into organic and inorganic matters and quantitatively analyzed.Results and Discussion : As a result of visually observing inside the membrane module that has produced drinking water for over 10 years, the inside of the No. 1 membrane module close to the inlet was contaminated with black foulants. On the other hand, in the case of No. 10 membrane module located farthest from the header pipe inlet, no foulants were observed with the naked eye. Also, it was observed from SEM photograph results that there were large differences in the surfaces among No. 1, 4, 6, 8 and 10 MF module fibers.Conclusion : Even after periodic physical and chemical cleaning, it was concluded that the fouling levels were different each other in the parallel arrayed low-pressure membrane modules. In addition, the pore size distribution and porosities of the membrane modules may vary depending on the position.

A simple water treatment procedure using a moringa activated two-tier filtration and Nano-silver impregnated ceramic pot system

This study was aimed at investigating the effectiveness of a customized ceramic pot treated with moringa oleifera and coated with silver sulphate solution for domestic water treatment. The customized pots were made by combining clay with sawdust at different ratios of 10:90, 20:80, 30:70, 40:60 and 50:50 respectively then coated with colloidal silver. The results obtained from all filtration pots indicated a 100% removal of coliform bacteria and Escherichia coli and were thus suitable for deployment in drinking water treatment. All ratios of the filtration pots were found to be effective, however, the 60:40 was found to be more practicable because of its higher filtration rate. Additionally, it was noted that the various filtration pots were very effective in lowering the higher values of the physicochemical parameters of pH, TS, TDS, TSS and turbidity as compared to the values of the world health organization (WHO) standard. This filtration method was however, not very effective in the reduction of the elemental concentration of the respective raw water samples. Overall, the results obtained encouraged the use of the two-tier filtration system especially in rural and developing areas where sophisticated dosing equipment or appropriate dose of the moringa oleifera is not required as different dosages were all effective and did not pose any undesirable effect on the physicochemical and elemental composition of the treated water samples. Â

A comparative study of various parameters of drinking water quality in Shahroud city, Iran: tap water, well water and bottled water

AbstractThe physical, chemical and microbial quality of bottled water, tap water and water supplied from wells in the city of Shahroud was compared. The results of the analysis showed that the measured parameters, except in minor cases, were of national and international standards. There was no significant difference between the quality of bottled water and tap water, as well as bottled water and water available in water supply resources in the city of Shahroud. Regardless of the area in which the study was conducted, it was found that there was no need for developing other types of water treatment systems such as bottled water and domestic water treatment systems. In many cases, since bottled water is exposed to intense sunlight during the transport process, there could be a leakage of plastic monomers from the bottle wall into the water in hot or cold conditions, which can endanger consumer health. Tap water supplied from the water supply resources in the city of Shahroud was found to be completely safe and posed no threat to consumer health.

Antimicrobial Activity of Sunflower (Helianthus annuus) Seed for Household Domestic Water Treatment in Buhera District, Zimbabwe.

Various plants have been used by humans for a very long time, and the uses vary, including food, medicine, toothpaste, dyes, food preservatives, water treatment, and beer brewing, among others. For food preservation and water treatment, the plant must have antimicrobial properties which are biocidal. For this research, extracts were obtained from sunflower (Helianthus annuus) seeds. The extracts were assessed for the presence of antimicrobial properties against three groups of bacteria, including faecal coliforms, total coliforms, and Escherichia coli (E. coli). Dosages of ground sunflower seeds ranging from 0.5 g to 4 g were administered to the three bacterial species and their susceptibilities to the antimicrobial agents were measured and recorded. The results indicate the presence of antimicrobial properties in sunflower. The antimicrobial activities were more effective on E. coli, with an average zone of inhibition of 12 mm with a 3 g dosage of sunflower seed extract. This was followed by total coliforms (11 mm) and lastly faecal coliforms (11 mm). These findings suggested that sunflower seeds proved to be potentially effective in treating water against microbial contaminants.

First report of the invasive Ceratium furcoides (dinoflagellate) in Paracambi Reservoir, Rio de Janeiro: Risks to the world's largest domestic water treatment plant

AbstractCeratium furcoides (Dinophyta) have gained international attention as invasive aquatic species, especially in South America, due to its fast proliferation into various aquatic systems and the subsequent adverse impacts on water quality and native biota. The present study reports the detection of dense populations of C. furcoides in the Paracambi Small Hydropower Plant (SHP) located in the Guandu River basin. Sampling was conducted at five sites during two sampling events in 2019 and 2020 during different seasons (spring and summer), respectively. We used two different standardized sampling methods, including surface collections (SS) (100‐ml) traditionally used for quantitative analysis of inland water phytoplankton, as well as filtration of 20‐L sub‐surface water (FS) through a zooplankton net. The cell densities were higher in SS (599 individuals/ml) than in FS (0.068 individuals/ml), possibly indicating a patchy distribution of Ceratium in the surface water layers. The total cell length exhibited high values (mean length of 249‐μm; mean width of 67‐μm), possibly accounting for water treatment impairment, an inability of zooplankton to consume them and/or fish gill clogging. This new observation within an extensively investigated area, and a source of water for nine million people, in the present study advocates for integrated samplings that also consider a search for cysts accumulated in the bottom sediments, as well as more detailed spatial and temporal investigations considering the salient features of C. furcoides’ populations.

Knowledge, Attitude & Practices towards Safe Water, Sanitation and Hygiene

Affordable and sustainable access to water, sanitation and hygiene (WASH) is a key public health issue and focus of Sustainable Development Goals. Literature showed that households having prior knowledge and an acceptable attitude towards WASH practices have less number of diseases. The main objective of the study was to explore the level of respondents' knowledge, attitude and practices towards safe Water, Sanitation and Hygiene Conditions in South Punjab, Pakistan. The study was mixed-method research. SPSS also applied, and results demonstrate that there was very lack of knowledge about safe WASH practices; the majority of respondents have a traditional attitude. Whereas only 27.3% of respondents have always access to safe drinking water, 96% of respondents were not using any domestic water treatment method, 22.9% were defecating in the open, and the percentage of always handwashing with soap was found to only 29.6%. Social Mobilization programs along with government action to ensure safe WASH conditions are recommended.

The construction and application of physiologically based toxicokinetic models for acrylamide, glycidamide and their biomarkers in rats and humans

Acrylamide (AA), a class 2A probable carcinogen to humans classified by the International Agency for Research on Cancer, has attracted extensive attention worldwide since it was widely used in industrial and domestic water treatment and detected in thermal processing foods. The metabolic adducts of AA and its primary metabolite glycidamide (GA) have been served as biomonitoring markers of AA intake, but the physiologically based toxicokinetics (PBTK) models to estimate internal dosimetry still remain unclear. An updated PBTK model for AA, GA and their metabolic biomarkers in rats and humans was developed and extended with time-course datasets from both literatures and our experiments. With adjustments to the model parameters, linear regression correlation coefficient (R2) between the fitting values and the validation datasets of rats and humans was greater than 0.76. The current model fits well with the experimental datasets of urinary N-acetyl-S-(2-carbamoylethyl)-l-cysteine (AAMA) and (N-(R,S)-acetyl-S-(carbamoyl-2-hydroxyethyl)-l-cysteine) (GAMA) of rats exposed to AA from 0.1 to 50 mg/kg b.w. and humans exposed to AA from 0.0005 to 0.020 mg/kg b.w., indicating the robustness of the current models. Parameters for adduct of AA with N-terminal valine of hemoglobin (AAVal) were extended to humans and validated. Kinetic parameters for rats were assessed and validated based upon fit to the experimental datasets for liver N3-(2-carbamoyl-2-hydroxyethyl)-adenine (N3-GA-Ade) and N7-(2-carbamoyl-2-hydroxyethyl)-guanine (N7-GA-Gua) adducts. Compared with the previous model, the developed model included the correlation between AA intake and its mercapturic acid adducts, AAMA and GAMA, in a larger dose range with new experimental data, and parameters for AAVal, N3-GA-Ade and N7-GA-Gua were improved and verified. The current multi-component PBTK models provide a superior foundation for the estimation of short-term to medium and long-term intake levels of human exposure to AA.

Biochemical responses of some aquatic plants as indicators for the treatment of inorganic nitrogen compounds in wastewater (Case study: Domestic water treatment plant in Babil Governorate, Iraq)

Biochemical responses of some aquatic plants as indicators for the treatment of inorganic nitrogen compounds in wastewater (Case study: Domestic water treatment plant in Babil Governorate, Iraq)

Biochemical responses of some aquatic plants as indicators for the treatment of inorganic nitrogen compounds in wastewater (Case study: Domestic water treatment plant in Babil Governorate, Iraq)

The current study was conducted to investigate the biochemical response of two plant species including Lemna minor and Ceratophyllum demersum as indicators for the treatment and reducing the concentrations of dissolved inorganic nitrogen compounds in wastewater collected from a domestic water treatment plant in Al-Maamera area in Babil Governorate, Iraq. The experiment included the cultivation of aquatic plants in 20-liter plastic basins, which contain domestic water collected from the sedimentation basins at the station after completing the physical and chemical treatment. Some physical and chemical tests were conducted and the concentrations of some compounds of dissolved inorganic nitrogen were measured by taking the water samples every three days for a period of twenty four days. The current study showed that the pH values were raised to the basal direction when wastewater treated with C. demersum, while the values fluctuated when using L. minor with treatment between low and slight increase at other times. On the other side, the efficiency of the aquatic plants used in current study in decreasing the values of both electrical conductivity and total dissolved solids was weak and was limited to the first days of treatment. The results recorded an increased oxygen concentration when wastewater treated with C. demersum compared to the control which recorded higher concentrations than L. minor. The study showed also that the L. minor and C. demersum have very high efficiency in reducing the inorganic nitrogen compounds. So that, in the case of L. minor, the highest removal rate of nitrite, nitrate and ammonia were 99.36%, 88.04% and 81.25 %, respectively, while in the case of C. demersum, the related rates were 99.36%, 78.8% and 86.6 % respectively. As for the physiological condition of the plants, the results in the current study showed that the total chlorophyll values in L. minor and C. demersum increased after completing the phytoremediation. The MDA content decreased, while CAT enzyme was not affected by both plants. The SOD enzyme was not also affected by L. minor, while a rise in this enzyme was recorded by C. demersum.