Water Ozone Research Articles

Evaluating source separation wastewater systems using traditional life cycle assessment and the planetary boundaries approach

Life cycle assessment (LCA) is a commonly used method for assessing environmental impacts of systems, but cannot produce absolute values, i.e. a comparison with existing calculated values, which represents limits of what can be emitted into the environment. Therefore, absolute environmental sustainability assessments have been developed to assess impacts against the planetary boundaries (PBs) of the safe operating space for humanity. Since PB-LCAs are novel, it is useful to analyze both results from this method and conventional LCAs, something which has not been done before. This study applied both methods to two full-scale sanitation systems in the city of Helsingborg, Sweden. The current conventional system for handling wastewater with active sludge and food waste to biogas production was compared with the novel project H+ source separation system with three pipes (food waste, grey and black water) with increased resource recovery through anaerobic digestion, ammonia stripping, struvite precipitation and pelletization. The Planetary Boundaries LCA (PB-LCA) results showed that both systems exceeded eight of the assigned shares of PBs, including climate change and biogeochemical flows of nutrients. Traditional LCA (ReCiPe impact assessment) showed net savings for the H+ system in a few categories and considerable reductions in several impacts, e.g., global warming potential (GWP), stratospheric ozone depletion, terrestrial acidification, and water consumption. In PB-LCA the H+ system gave additional impacts in both assessments for a few categories, mostly due to high consumption of chemicals in the ammonium stripping process used for nutrient recovery. In conclusion, the combined assessments highlight hot-spots for process optimization in the H+ system. From a methodological standpoint, PB-LCA still needs improvements to better reflect avoided burdens and results from traditional LCA should be fully transparent and analyzed carefully. The assessment methods complement each other and can be combined to better represent environmental performances of systems.

Different genotypes of tartary buckwheat can regulate the transformation of nitrogen through the secretion of organic acids under low nitrogen stress

Roots respond to nitrogen deficiency by altering their physiological and metabolic responses. Soil nitrogen invertase activity and the diversity of nitrifying microorganisms (AOA and AOB) significantly affect the nitrogen cycle in soil. As an important part of root exudates, organic acids can reflect the dynamic changes of plant roots in soil. However, it is not clear how the barren-tolerant genotype plant varieties show their stress resistance through organic acids regulating nitrogen transformation under low nitrogen environment. Here, we selected two Tartary buckwheat varieties: HeiFeng1 (HF, low nitrogen sensitive cultivar) and DiQing (DQ, low nitrogen tolerance cultivar) for a two-year experiment. The urea addition levels of 0, 80, and 160 mg kg−1 soil were respectively set as nitrogen sources, and ozone sterilization experiments were designed to completely remove microbial effects to distinguish the contribution of plant roots and microorganisms to nitrogen invertase and organic acids (400 ml 1 mol L−1 ozone water daily, 0 nitrogen fertilizer, O3). The results showed that malic acid and tartaric acid were the main organic acids secreted by tartary buckwheat. The total amount and richness of organic acids in Diqing were higher than those in Heifeng, and organic acids directly affected the diversity of ammonia-oxidizing microorganisms (AOA and AOB), changed the soil environment by affecting soil water content, and indirectly affected the activity of nitrogen invertase. At the same time, it was found that the increase of nitrogen application rate would increase the proportion of key bacteria such as Nirtrosomonas and Nitrosospira in AOB of tartary buckwheat soil. Finally, Diqing tartary buckwheat was proved to be more suitable for planting in the nitrogen-deficient Loess Plateau, but attention should be paid to the negative effects of AOB and organic acids.

Efficient degradation of dye wastewater by catalytic ozonation reactive ceramic membrane with facile spraying of nano Ti[sbnd]Mn oxides: A pilot scale attempt

The traditional treatments of dye wastewater exist obvious drawbacks of low efficiency but high energy consumption. To solve this problem, based on the concept of combining degradation and separation, an integrated process of TiMn oxides catalytic ozonation and ceramic membranes (CM) was proposed to degrade dye wastewater in this paper. Specifically, TiO2/MnO2 hybrid catalysts were loaded on the surface of CM with a spraying printing method to prepare a reactive ceramic membrane (TiO2/MnO2-CM). The degradation efficiency and permeate flux of the TiO2/MnO2-CM + O3 system on Rhodamine B (RhB) were investigated. The SEM results illustrated that the catalyst was successfully loaded on the surface of CM. Additionally, the degradation efficiency of RhB was 100 % in 40 min under the conditions of catalyst spray layers 12, ozone concentration 2.5 g/cm3, and initial concentration of RhB 20 mg/L, and the permeate flux of TiO2/γ-MnO2-CM was as high as 125.399 kg/ (m2·h). Supplementarily, the study revealed that TiO2/γ-MnO2-CM could increase the concentration of ozone in water and catalyze ozone to produce more hydroxyl radicals (•OH), and the concentration of dissolved ozone was 0.7545 mg/L, •OH 68.16 μmol/L respectively. Eventually, the catalytic ozonation TiO2/γ-MnO2-CM device was scaled up, which treated 96 L RhB with a degradation efficiency of 100 % in 50 min. The work gives a solid foundation and scientific value for the industrial application of reactive CM in water or wastewater treatment.

Investigation of surfactant effect on ozone bubble motion and mass transfer characteristics

The low solubility and low mass transfer efficiency of ozone (O3) in water are important reasons for limiting the application of ozone oxidation technology and advanced ozone oxidation technology. Low-dose surfactants were introduced to affect the behavior of ozone bubbles, influencing the ozone mass transfer efficiency. The motion of ozone bubbles in three different types of surfactant solutions (polyoxyethylene lauryl ether (Brij35), sodium dodecylsulfate (SDS), and cetyltrimethylammonium bromide (CTAB)) was observed. The decrease in surface tension led to a decrease in bubble size, a tendency to spherical shape, an increase in gas content and residence time, a decrease in lateral displacement of a single bubble, and a more stable trajectory. The effect of surfactants on ozone mass transfer was further investigated. The addition of surfactant was found to increase the gas-liquid interface area but decrease the liquid phase mass transfer coefficient, and the extent of the two opposite effects varied for different surfactants. The analysis combined with the removal of pollutant p-Nitrophenol (PNP) showed that the addition of the nonionic surfactant Brij35 and the anionic surfactant SDS inhibited ozone mass transfer, while low concentrations of the cationic surfactant CTAB enhanced ozone mass transfer. When the CTAB concentration was 3 mg L−1, the ozone volume mass transfer coefficient reached a maximum of 0.2902 min−1.

Effect of crystalline phase of MnO2 on the degradation of Bisphenol A by catalytic ozonation

In recent decades, manganese oxide (MnO2) has been an attractive catalyst for organic pollutants removal from wastewater by ozonation. However, the effect of the MnO2 crystalline phase on Bisphenol A ozonation in water has never been investigated. In the present study, three crystalline phases of MnO2 were synthesized by hydrothermal method, including α-, γ-, and δ-MnO2, the last generating three different kinds. The as-prepared MnO2 were evaluated in the ozonation of Bisphenol A (BPA) and correlated with their physicochemical properties obtained by different characterization techniques. The activity of MnO2 polymorphs for TOC removal followed the order of γ-MnO2 > δ3-MnO2 > δ1-MnO2 > α-MnO2 > δ2-MnO2. The catalytic activity of MnO2 strongly depended on the presence of active sites such as density of the surface oxygen vacancy, Mn+3/Mn+4 ratio, and OH-groups on the catalyst surface. The catalysts with the highest amount of oxygen vacancies (but the minor density of the surface oxygen vacancy) and OH-groups were δ3-MnO2 and γ-MnO2, respectively, demonstrating excellent catalytic activity on BPA removal. The effect of stabilities of δ3-MnO2 and γ-MnO2 was also investigated in this research. Furthermore, the toxicity bioassay based on Lactuca sativa seeds demonstrated that by-products generated during conventional and catalytic ozonation were non-toxic. The elimination of the model mixture of emergent compounds in four types water were also tested with δ3-MnO2 and γ-MnO2, obtaining mineralization values around 47–59 % and 40–55 %, respectively, at 120 min compared with 18–23 % of conventional ozonation.

Effectiveness of Ozonation for Improving the Microbiological Safety of Fresh-Cut Parsley (Petroselinum crispum) Leaves

In the last decade, fresh-cut plants have become a more popular flavoring additive in food. It is important to find an effective method for ensuring the safety and quality of plant materials used as food additives. Ozonated water is being considered by the EFSA for approval as a cidal agent for plant protection. The objective of this study was to evaluate the effectiveness of ozonated water in improving the microbial safety of fresh-cut parsley leaves, with a particular focus on mesophilic and psychrotrophic bacteria and fungi. The yeasts and bacteria were identified with the MALDI-TOF MS system. Color changes on the surface of the parsley samples were measured in the CIE L*a*b trichromatic color model. The chemical composition of the essential oil was evaluated via gas chromatography with mass spectrometry (GCMS). The microbial level of the fresh leaves varied and depended on the season. The highest microbial levels were found in the leaves picked in the summer and autumn, at 104 to 106 CFU/g for fungi and 106 to 108 CFU/g for bacteria. Among the isolates with the highest isolation frequency, bacteria belonging to Pseudomonas fluorescens, Staphylococcus warneri, and Bacillus megaterium dominated. The dominant yeasts and molds were Candida sp., Rhodotorula sp., Cladosporium sp., and Fusarium sp. The conditions for water ozonation (ozone dose and time) were established for both mono- and mixed cultures. Time of 3 min, ozone content of 0.5, O3 mg/L or 1 min, and 1.5 mg of O3 mg/L were sufficient for a 90% reduction in the number of living microorganisms. Yeasts and bacteria were sensitive to ozone treatment, excluding P. fluorescens rods. The tested mold strains were the most resistant. However, it was noted that organic matter might reduce the decontamination effect. The effectiveness of ozonation was negatively influenced by organic compound content above 1%. Spectrophotometric measurements of parsley leaves after ozonation, especially after 3 min treatment at 1.5 O3 mg/L, revealed morphological changes. The CIELAB color space (L*a*b*) changed in the direction of lightness and yellowness; however, ΔE showed no statistically significant differences in comparison with the untreated leaves. In preliminary studies, no differences were noted in GLC-MS chromatograms for essential oils of parsley leaves before and after ozonation. The aroma of parsley treated with ozonated water was more intensely herbal than the control sample, probably due to the higher content of α and β phellandrene. The results of this study show that decontamination of parsley leaves by ozonated water containing 1.5 O3 mg/L in a closed 5 min process can effectively ensure the microbiological quality of fresh-cut parsley leaves. It can be concluded that ozone treatments in aqueous form appear to provide promising qualitative and quantitative results for the decontamination of this fresh-cut plant material. However, more work is necessary to study chemical and volatilome changes. Especially the sensory analyses should be conducted before and after ozone treatment.

Environmental Impact Analysis of Functional Retrofitting Measures in Buildings

A large number of existing building stock in India was built before the implementation of government guidelines mandating the Green Building Codes. These buildings have been operating with various inefficiencies pertaining to their resource consumption and emissions. Literature suggests that the option of functional retrofitting of building has a potential to reduce this inefficiency by up to 50%. This paper investigates this potential by analysing actual cases of functional retrofitting of buildings (for achieving greater operational efficiency) in Indian context. The environmental impact analysis in this study includes the impact categories of primary energy demand, global warming potential, abiotic depletion potential, ozone depletion potential and water resource consumption for both pre-retrofit and post-retrofit scenario of building. The results are then correlated to the initial cost of functional retrofitting for each case in order to identify the inter-relationship and trend with respect to the level of intervention opted for the cases.

The disinfection effectiveness of ozone water and 4.8% chloroxylenol against the number of bacterial colonies in dental extraction instruments at the USU Dental and Oral Hospital in October-December 2022

Background: The application of disinfectants on dental instruments is one way to prevent cross-infection. Cross infection can occur due to microorganisms found in blood, saliva and dental plaque which can contaminate the instruments used by dental health workers. Thus, indirect contact transmission of pathogenic microorganisms occurs from instruments that have been contaminated by dental health workers. Ozone water and 4.8% chloroxylenol are disinfecting agents used to disinfect medical instruments. This study aimed to determine the effectiveness of disinfection of ozone water and 4.8% chloroxylenol in reducing the number of bacterial colonies on dental extraction instruments at the USU Dental and Oral Hospital between October-December 2022. Methods: The samples used were mandibular molar pliers that have been used in tooth extraction procedures. This study was experimental and used three sample groups, where each group consisted of 10 tooth extraction instruments. The treatment group used ozone water and 4.8% chloroxylenol and the negative control group was cleaned with distilled water. The test effectiveness in this study used bacteria colony counter using the scatter cup method. Data were analyzed using the Kruskal Wallis and Mann-Whitney U tests. Results: The results of the data analysis showed a p-value ≤0.001, which means that there was a significant difference in the disinfection using ozone water and 4.8% chloroxylenol on the number of bacterial colonies on dental extraction instruments. The results of this study show that the average number of bacterial colonies formed in the ozone water treatment group was 4.00 ± 4.32, 16.00 ± 6.65 in the 4.8% chloroxylenol treatment group, and 217.50 ± 39.24 in the negative control group (Aquadest). Conclusions: From this study it can be said that ozone water is more effective in disinfecting dental extraction instruments than 4.8% chloroxylenol.

Resist Removal Using Laser Irradiation Combined with Ozone Water Treatment

Resist Removal Using Laser Irradiation Combined with Ozone Water Treatment

A multi-model assessment of the Global Warming Potential of hydrogen

With increasing global interest in molecular hydrogen to replace fossil fuels, more attention is being paid to potential leakages of hydrogen into the atmosphere and its environmental consequences. Hydrogen is not directly a greenhouse gas, but its chemical reactions change the abundances of the greenhouse gases methane, ozone, and stratospheric water vapor, as well as aerosols. Here, we use a model ensemble of five global atmospheric chemistry models to estimate the 100-year time-horizon Global Warming Potential (GWP100) of hydrogen. We estimate a hydrogen GWP100 of 11.6 ± 2.8 (one standard deviation). The uncertainty range covers soil uptake, photochemical production of hydrogen, the lifetimes of hydrogen and methane, and the hydroxyl radical feedback on methane and hydrogen. The hydrogen-induced changes are robust across the different models. It will be important to keep hydrogen leakages at a minimum to accomplish the benefits of switching to a hydrogen economy.

Research of the Process of Ozonation and Sorption Filtration of Natural and Anthropogenicly Pollated Waters

This scientific research work is written based on the problem of studying the process of ozonation and sorption filtration of natural and anthropogenically polluted waters. Scientific research work of our country is diverse It was prepared in the laboratory of water ozonation, and purification technology and equipment of Kazakh National Research Technical University named after K. I. Satbayev based on long-term research conducted in cities and regions. The current state of ozonation equipment and active carbon production is considered in the research work. The scientific research work is intended to solve problems and tasks related to the use of ozonation and sorption water purification methods for employees of the sector of quality water supply and water treatment. In addition, the research work is devoted to the problems of water purification using ozone. Provides general information about the properties of ozone, its interaction with inorganic and organic compounds. The main methods of obtaining ozone, the effect of design parameters on the efficiency of ozonators are shown. The main domestic and foreign manufacturers of ozonation equipment are presented. In the research paper, considering the effectiveness of removing various organic and inorganic pollutants of natural and anthropogenic origin, microbiological pollutants, the authors' long-term research on purification and disinfection of natural waters are systematized. Production experience of using ozone in foreign and Kazakh water facilities, as well as in local water treatment plants is presented.

Surface Solar Extremes in the Most Irradiated Region on Earth, Altiplano

Abstract Satellites have consistently pointed to the Altiplano of the Atacama Desert as the place on Earth where the world’s highest surface irradiance occurs. This region, near the Tropic of Capricorn, is characterized by its high elevation, prevalent cloudless conditions, and relatively low concentrations of ozone, aerosols, and precipitable water. Aimed at studying the variability of the surface solar irradiance and detecting atmospheric composition changes in the Altiplano, an atmospheric observatory was set up in 2016 at the northwestern border of the Chajnantor Plateau (5,148 m MSL, 22.95°S, 67.78°W, Chile). Here, we report on the first 5 years of measurements at this observatory that establish the Altiplano as the region that receives the highest-known irradiation on Earth and illuminate the unique features of surface solar extremes at high-altitude locations. We found that the global horizontal shortwave (SW) irradiance on the plateau is on average 308 W m−2 (equivalent to an annual irradiation of 2.7 MWh m−2 yr−1, the highest worldwide). We also found that forward scattering by broken clouds often leads to intense bursts of SW irradiance; a record of 2,177 W m−2 was measured, equivalent to the extraterrestrial SW irradiance expected at approximately 0.79 astronomical units (AU) from the Sun. These cloud-driven surface solar extremes occur on the Chajnantor Plateau at a frequency, intensity, and duration not previously seen anywhere in the world, making the site an ideal location for studying the response of photovoltaic (PV) power plants to periods of enhanced SW variability.

P6 | Potential therapeutic effect of ozone water on inflammatory skin symptoms and periodontal diseases in canine

Journal of Veterinary Pharmacology and TherapeuticsVolume 46, Issue S1 p. 87-88 POSTER PRESENTATIONS P6 | Potential therapeutic effect of ozone water on inflammatory skin symptoms and periodontal diseases in canine First published: 11 June 2023 https://doi.org/10.1111/jvp.13285Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL No abstract is available for this article. Volume46, IssueS1Special Issue: 15th International Congress of the European Association for Veterinary Pharmacology and Toxicology held Bruges, Belgium, July 2–5, 2023June 2023Pages 87-88 RelatedInformation

Analysis of Water-Soluble Vitamin Change in Tomato (S.lycopersicum) Due to Ozonolysis of Imidacloprid Degradation Treatment by Using Spectrometry and HPLC Method

In this study, the effect of imidacloprid degradation on the reduction of water-soluble vitamins in tomatoes was observed, such as ascorbic acid, pyridoxine, niacin, and thiamine. Analysis was carried out using a spectrophotometer and high-performance liquid chromatography. Degradation method with ozone water for 15 minutes showed a better result than the ozonolysis method because the decrease in levels of water-soluble vitamins is smaller. The percentage decrease of each water-soluble vitamin in ozone water method is ascorbic acid by 17,103%, pyridoxine by 6,723%, niacin by 2,781%, and thiamine by 0,333%. Ozone water methods also produce a high percentage of degradation which is 90,56%.

Cu Species-Modified OMS-2 Materials for Enhancing Ozone Catalytic Decomposition under Humid Conditions.

Manganese oxide octahedral molecular sieves (OMS-2) exhibit an excellent performance in ozone catalytic decomposition in dry atmosphere conditions, which however is severely limited by deactivation in humid conditions. Herein, it was found that the OMS-2 materials modified with Cu species could obviously improve both the ozone decomposition activity and water resistance. Based on the characterization results, it was found that these CuOx/OMS-2 catalysts exhibited dispersed CuOx nanosheets attached and located at the external surface accompanied with ionic Cu species entering the MnO6 octahedral framework of OMS-2. In addition, it was demonstrated that the main reason for the promotion of ozone catalytic decomposition could be ascribed to the combined effect of different Cu species in these catalysts. On the one hand, ionic Cu entered the MnO6 octahedral framework of OMS-2 near the catalyst surface and substituted ionic Mn species, resulting in an enhanced mobility of surface oxygen species and formation of more oxygen vacancies, which act as the active sites for ozone decomposition. On the other hand, the CuOx nanosheets could serve as non-oxygen vacancy sites for H2O adsorption, which could alleviate the catalyst deactivation to some extent caused by the occupancy of H2O on surface oxygen vacancies. Finally, different reaction pathways for ozone catalytic decomposition over OMS-2 and CuOx/OMS-2 under humid conditions were proposed. The findings in this work may shed new light on the design of highly efficient catalysts for ozone decomposition with improved water resistance.

Rotating Packed Bed Reactor Integrated with Plasma: Mass Transfer Intensification and Wastewater Treatment

When oxygen plasma contacts with liquid, abundant reactive species are generated to degrade the contaminant. Ozone is the main reactive species in the gas phase, but only part of it is utilized during wastewater treatment owing to its low solubility. In this work, a novel rotating packed bed reactor integrated with plasma (plasma-RPB) was developed to fully utilize ozone and enhance wastewater treatment. The ozone–water mass transfer efficiency of the plasma-RPB with different liquid distributor structures was evaluated. Subsequently, a dimensionless correlation for predicting the volumetric mass transfer coefficient of the plasma-RPB with the rotating cylinder was established, and the deviation between the predicted and experimental values was within ±6%. Employing the plasma-RPB, sulfamethoxazole and TOC removal efficiency reached up to 87.6 and 82.7% within 5 min, respectively, exhibiting prominent degradation performance compared with other advanced oxidation processes. This work provides an effective route for wastewater treatment.

Non-Thermal Plasma Review: Assessment and Improvement of Feasibility as a Retrofitted Technology in Tertiary Wastewater Purification

Chlorination, ozonation and non-thermal plasma water purification technologies were compared in terms of their effectiveness, efficiency, capital and operating costs, energy yield and chemical demand. Retrofitting plasma technology to chlorination plants offered the lowest capital cost (ZAR 14,000 or USD 253,376 based on the current South African Reserve Bank rate of ZAR/USD of 18.0983) and the most effective contaminant removal (of the three possible combinations). How- ever, this combination yielded the highest operating costs (ZAR 586,000 per annum or USD 10.6 million) and the lowest energy efficiency. It was concluded that retrofitting chlorination plants with plasma technology is feasible. However, plasma generators should be redesigned to consume less energy or to operate using renewable energy. Furthermore, research should be performed on contaminants of emerging concern to establish a deadline after which their concentration must not exceed a specified limit. This will accelerate the implementation of plasma technology and secure the health of our posterity.

Organosulfur compounds in ambient fine particulate matter in an urban region: Findings of a nontargeted approach

Organosulfur compounds (OSCs) are important components of fine particulate matter (PM2.5); however, little information is available on OSCs in urban regions due to their chemical complexity, especially for novel species such as aromatic sulfonates. To supplement the detection technique and systematically identify OSCs, in this study we developed a nontargeted approach based on gas chromatography and high-resolution mass spectrometry (GC-HRMS) to screen OSCs in PM2.5 of urban Beijing and provide field evidence for their source and formation mechanism. 76 OSCs were found through mass difference of sulfur isotopes and characteristic sulfur-containing fragments. 6 species were confirmed as aromatic sulfonates by authentic standards. 32 OSCs showed higher levels in the heating season, presumably because of the intensive emission, especially from coal combustion. While certain species, with 2-sulfobenzoic acid as the representative, were 2.6-times higher in the non-heating season than in the heating season. Such species were significantly correlated with ozone and aerosol liquid water content (r = 0.2–0.8, p < 0.05), implying an oxidation-involved aqueous-phase formation in the atmosphere. In addition, with an average proportion of ∼95 % of the total sulfobenzoic acids, the predominance of the 2-substitution product over its isomers of 3- or 4-sulfobenzoic acid suggests a more plausible mechanism of radical-initiated reaction of phthalic acid followed by sulfonation, with atmospheric reactivity indicated by ozone and temperature as the determining factor. This study provided not only a nontargeted approach for OSCs in ambient PM2.5, but also field evidence on their secondary formation proposed in previous simulation studies.

Effects of Cold Plasma and Ozone Water Treatment on Micronutrient Solubility

Cold plasma and ozone sanitation of irrigation solutions can oxidize both microbes and non-target micronutrients because their high oxidation-reduction potential (ORP) is a non-selective mode of action. The objective of this study was to evaluate the effects of cold plasma and ozone treatment on oxidation of iron and manganese in nutrient solutions containing one of four iron chelates (iron-ethylenediaminetetraacetic acid (Fe-EDTA), iron-diethylenetriaminepentaacetic acid (Fe-DTPA), iron-ethylenediamine-N,N′-bis(2-hydroxyphenylacetic acid) (Fe-EDDHA), and hydroxybenzyl ethylenediamine (Fe-HBED)). Nutrient solutions were recirculated through the cold plasma or ozone system until the ORP reached 700 mV. The concentrations of total dissolved iron, manganese, and chelated iron were measured before and after passing through the treatment systems. Both cold plasma and ozone oxidized chelates and decreased the solubility of iron and manganese. Cold plasma and ozone had similar effects on micronutrients, pH, electrical conductivity, and dissolved oxygen at a standardized target ORP of 700 mV. Fe-EDTA was the most resistant chelate to oxidation. With Fe-EDTA, ORP increased more quickly, and the concentration of chelated Fe decreased less with the increasing ORP over time compared with Fe-DTPA, Fe-EDDHA, and Fe-HBED. The concentration of chelated Fe decreased by up to 80% for EDDHA at 700 mV compared with a 20% decrease for EDTA. The concentration of Mn decreased by up to 85% at 700 mV. The design of water treatment with cold plasma or ozone therefore requires consideration of secondary effects on micronutrients. The treatment dosage, flow rate, and nutrient solution at a particular grower operation are likely to affect the quantity of micronutrient fertilizer that needs to be supplemented following treatment. Use of Fe-EDTA is one strategy to reduce the loss of iron and increase residual ORP that is available for sanitation.

Life Cycle Assessment for Geopolymer Concrete Bricks Using Brown Coal Fly Ash

Traditionally, the construction industry has predominantly used Portland cement (PC) to manufacture bricks, as it is one of the most-commonly available building materials. However, the employment of waste industrial material for brick production can lead to a significant improvement in terms of sustainability within the construction sector. Geopolymer bricks made from brown coal fly ash, a promising industrial waste by-product, serve as a potential alternative. Conducting a life cycle assessment (LCA), this study thoroughly evaluated the entire manufacturing process’s environmental impact, from source material acquisition and transportation to brick manufacturing, distribution, usage, and end-of-life, for brown coal bricks as compared to PC bricks. The LCA of the brown coal bricks revealed that their primary environmental impacts stemmed from the raw material manufacturing and usage, while exhibiting substantial reductions in ozone depletion, water depletion, and metal depletion. These findings highlighted the environmental advantages of the brown coal bricks and their potential to revolutionize sustainable construction practices.