Ozone Dose Research Articles

Potentials for patients with severe arterial hypertension, by using antihypertensive pharmacotherapy combined with ozone therapy and nasal laser therapy.

Background: More people die each year from cardiovascular diseases than from any other cause. Arterial hypertension (AH) is a particularly important public health issue in Mongolia which has one of the highest mortality rates from hemorrhagic stroke in the world. Antihypertensive pharmacological therapy combined by other non-medication therapy is well-studied in patients with mild and moderate AH. However, studies that have investigated combination of low intensity laser irradiation and ozone therapy in patients with severe AH are lacking. The objective of the present work was to develop methods using low intensity laser irradiation therapy (LLLT) combined with major autohemotherapy (MAH) for the patients presenting with AH. 
 Studies have shown that LLLT is capable of inducing a photobiological response within the cells which modifies the micro and macrovascular response; this accompanies evidence showing the systemic effects even using in nasal laser irradiation (NLI). 
 Oxygen-ozone therapy exerts a positive effect on the platelet aggregation, cell remodeling, cytoskeletal elements organization and mitochondria structure. Due to O2-O3 therapy is an effective method in hypertension, and it diminishes the hypoxia state of various tissues. 
 In recent years, scientists have made great progress in the area of pharmacotherapy for patients with AH. Drugs help to achieve the target level of arterial blood pressure, particularly in patients with mild and moderate AH. With a higher degree of AH (severe arterial hypertension – the 3rd degree of arterial hypertension) the effectiveness of pharmacological therapy decreases and to achieve the target level of arterial blood pressure it is necessary to use a combination of all major groups of antihypertensive medicines.
 
 Method and Result: The study was held at Wellness Med Hospital Mongolia since the beginning of 2021 until the end of year. The study included a total of 60 patients of any age (63% of men and 37% of women) having AH associated with coronary heart disease and abnormal blood lipid spectrum. Initially, clinical-instrumental and laboratory examination, blood pressure registration and daily arterial blood pressure monitoring were carried out. Suitable drugs were selected for all the patients. 3 months after starting drug treatment the patients were divided in 2 groups each comprising 30 patients matched for age, sex, severity of clinical conditions, and character. The patients of the first group were prescribed combination with NLI and ozone therapy (MAH) in addition to drugs. For ozone therapy used Ozomed smartline ozone generator by Hansler Medical, Germany. The total dose of ozone to be given at each session will vary according to the general condition of the patient. Intervals from daily to weekly and twice a week. Ten to twelve treatments are considered as one course of treatment. Also, as cycles to be given once or more times per year. It may vary from less than 1000 µg to 3000 µg. This procedure is in line with the Madrid Declaration (ISCO3/QAU/01/03). The ozone concentration in the O2-O3 gas mixture were between 20 µg/ml to 35 µg/ml. The volume of blood to use varies between 50 mL and 100 ml. For NLI therapy we used Semiconductor laser Therapeutic apparatus Model W-001 by Fithope, China. The laser watch with nasal laser irradiation with 650nm (5mW) of lights. Used this equipment same day with Ozone therapy for about 30-40 minutes each time. If AH was higher used the laser therapy longer time. 
 The second group of patients continued receiving drugs alone. 3 months later, average daily blood pressure (BP), systolic BP and diastolic BP were compared in both groups. Three months after both groups demonstrated a significant decrease in SBP and DBP, but these indicators remained higher than normal and did not reach the target level. Three months after the inclusion of MAH+NLI in the comprehensive treatment, the first group demonstrated a significant decrease in BP (systolic and diastolic), not only in comparison with the initial data, but also with the data observed three months after PT. After 6 months SBP and DBP in the first group were significantly lower compared with those of patients in the second group. The inclusion of MAH+NLI in addition to multicomponent antihypertensive drugs is a promising treatment option for severe AH. 
 
 Discussion: Drug therapy is not sufficient for the elimination of cellular-tissue and microcirculatory disorders in case of severe AH, it should be advisable to include MAH+NLI into the multicomponent treatment, and positive changes in the indicators of the 1st group of patients after the inclusion of MAH+NLI are suggestive of it. 
 The oxygen-ozone therapy and LLLT seem to have no adverse events or side effects. Moreover, it is very cost-effective, as standard treatment costs can be reduced by 25% also.

Ozone therapy in mitochondrial dysfunction abnormalities in major psychiatric disorders

The pathogenesis of major psychiatric disorders has been highlighted in the last decade, in addition to neurobiochemical imbalances and the presence of multisystemic mechanisms, dominated by mitochondrial dysfunction, inflammatory processes, immune imbalances, ROS (Reactive Oxygene Species) hyperactivity and endothelial dysfunction.
 This complex of multisystemic mechanisms results in incomplete therapeutic responses to therapeutic approaches based on the correction of homeostasis imbalances in biochemical systems. Partial correction of symptoms cannot balance multiple systemic dysfunctions and mitochondrial activity. In this context,there is a risk of neurodegenerative developments, which are announced by the occurrence of partial or total resistance to pharmacological therapies.
 Ozone is a factor with antioxidant, antiapoptotic action and which improves autophagy, a phenomenon that can improve mitochondrial dysfunction. The balance between the therapeutic use of ozone doses can be shaped by the concomitant administration of antioxidants.
 Psychotropic medication has a neurotoxic effect that potentiates ROS activity and the apoptotic mechanisms of neural structures, favoring brain structural alterations.
 Pathogenic patterns of major psychiatric disorders suggest possible benefits of complementary therapies with ozone oxygen therapy, which could reduce the number of adverse neurodegenerative development.

Mechanism of real-time capture of organics by in-situ-formed microbubble flocs to enhance organics removal in hybrid ozonation-coagulation process

The over-oxidation of organic pollutants by pre-ozonation leads to a decreased removal efficiency of coagulation. In this study, it was demonstrated that organics modified by ozonation can be captured in real time by microbubble flocs mediated by the interaction among ozone, Al species, and other organics using the hybrid ozonation-coagulation (HOC) process, which avoids further oxidation of the modified organics. Compared with the pre-ozonation-coagulation process, this real-time capture strategy during the HOC process can increase organics removal efficiency, and broaden the ozone dosing range. The synergistic effect of Al species and ozone enhanced hydroxyl radicals (·OH) formation, which increased the content of carboxyl and hydroxyl groups in the modified intermediates while retaining their original macro aromatic structure. That modified intermediates can be captured and complexed by Al species in the HOC process in real time was verified by differential absorbance spectroscopy (DAS). Al species are complexed with carboxyl and hydroxyl groups of organic compounds to form Al-organic complexes that have COAl coordination bonds. These complex structures protect the modified organic compounds during immediate contact with and decomposition by ozone. The existence of ozone can increase the formation of poly Al species via hydroxyl bridges, thus causing the soluble small-scale metal complex to form insoluble flocs. The surface of flocs can be oxidized and modified, thus strengthening the surface coordination of residual organics in water and further improving their removal efficiency.

Improvement of coal gasification reverse osmosis concentrate treatment by Cu-Co-Mn/AC catalytic ozonation.

Approximately 20% of concentrate will be produced from coal gasification wastewater after reverse osmosis treatment. The organic matter contained in the concentrate affects its evaporation crystallisation; therefore, the refractory organics must be removed. In this study, Cu-Co-Mn/AC catalytic ozonation was used to treat reverse osmosis concentrate (ROC). With the addition of the Cu-Co-Mn/AC catalyst, the production of ·OH increased by 82 μmol/L, thereby enhancing the ozonation performance. The pH, ozone dosage, and catalyst dosage all affected the catalytic ozonation performance. By constructing a response surface model, it was found that the catalyst dosage had the most significant effect on the catalytic ozonation performance. The predicted optimal reaction conditions were pH = 9.02, ozone dosage = 1.08 g/L, and catalyst dosage = 1.33 g/L, under which the chemical oxygen demand (COD) removal reached a maximum of 81.49%.

Advanced Treatment of Laundry Wastewater by Electro-Hybrid Ozonation–Coagulation Process: Surfactant and Microplastic Removal and Mechanism

Laundry wastewater is supposed to be one of the most important sources of surfactants and microplastics in the wastewater treatment plant. Consequently, the aim of the study was evaluating the performance and mechanism of the electro-hybrid ozonation–coagulation (E-HOC) process for the removal of surfactants and microplastics. In this study, the efficiency of the E-HOC process for surfactant and microplastic removal was examined at different current densities and ozone dosages. Under the optimal reaction conditions (current density 15 mA·cm−2, ozone dosage 66.2 mg·L−1), both the removal efficiency of surfactant and microplastic can reach higher than 90%. Furthermore, the mechanism of surfactant and microplastic removal was investigated by electron paramagnetic resonance (EPR) and Fourier transform infrared spectroscopy (FT-IR). The results showed that the E-HOC (carbon fiber cathode) system can produce more reactive oxygen species (ROS), which can significantly improve the removal of the contaminants. In addition, the shape, size and abundance of the microplastics were analyzed. It was found that the shape of the microplastics in laundry wastewater is mainly fiber. Microplastics less than 50 μm account for 46.9%, while only 12.4% are larger than 500 μm. The abundance of microplastics in laundry wastewater ranges between 440,000 and 1,080,000 items per 100 L. The analysis of microplastics by FT-IR showed that most of the microplastics in laundry wastewater were polyethylene, nylon and polyester. These results indicated that the E-HOC process can effectively remove surfactants and microplastics from laundry wastewater.

Activated sodium percarbonate-ozone (SPC/O3) hybrid hydrodynamic cavitation system for advanced oxidation processes (AOPs) of 1,4-dioxane in water

Hydrodynamic cavitation (HC) was employed to activate sodium percarbonate (SPC) and ozone (O3) to degrade recalcitrant 1,4-dioxane. The degradation efficiency > 99 % with a rate constant of 4.04 × 10−2 min−1 was achieved in 120 min under the optimal conditions of cavitation number (Cv) 0.27, pH 5, molar ratio of oxidant to pollutant (rox) 8, ozone dose of 0.86 g h−1 under 25 ± 2 °C with initial concentration of 1,4-dioxane 100 ppm. The application of HC with SPC/O3 increased the degradation efficiency by 43.32 % in 120 min, confirming a synergistic effect between the coupled processes. In addition, the degradation efficiency of 1,4-dioxane in HC/SPC/O3 was superior as compared to HC/H2O2/O3, suggesting that the presence of SPC has a significant role in degradation of 1,4-dioxane. Radical quenching experiment revealed highest contribution of hydroxyl (HO) radicals in the degradation of 1,4-dioxane among carbonate (CO3−) and superoxide (O2−) radicals. The presence of co-existing anions resulted in an inhibitory effect in the following order: SO42− > NO3− > Cl−. Based on GC–MS analysis, ethylene glycol diformate (EGDF) was detected as the main degradation product of 1,4-dioxane. The observed intermediate supports the radical route of 1,4-dioxane oxidation, which involves H-abstraction, ΔC-C splitting at the α-C position, subsequent dimerization, fragmentation and mineralization. Electric energy per order (EEO) for best process was 102.65 kWh·m−3·order−1. Total cost of treatment was estimated as approx. 12 USD/m3. These findings confirmed the SPC as an efficient, environmentally-friendly alternative to H2O2 and broadened the scope of HC-based AOPs for water and wastewater treatment.

Effects of Ozone Dose and Contact Time on Ozonation Process Performance for Treatment of High Rate Activated Sludge Process Effluent

ABSTRACT In recent years, there has been an increase in the interest on organic compounds originating from anthropogenic activities. The presence of these micropollutants in waterbodies can be detrimental for the aquatic organisms even at their trace concentrations. Removal of micropollutants from wastewater by conventional treatment methods is quite limited, thereby existing wastewater treatment plants are not capable of removing these micropollutants. This study investigated the removal of 27 micropollutants and conventional pollution parameters by ozonation of the effluent from a pilot-scale high-rate activated sludge system treating municipal wastewater. Different ozone dosages and contact times were tested during the study. Results revealed that 7 out of 27 micropollutants were detected in the effluent. Over 45% chemical oxygen demand (COD) removal and over 65% total suspended solids (TSS) removal were achieved by the ozonation process. Among the various ozone dosage and contact time combinations investigated in the study; 6 mg/L ozone dosage-20 min contact time, and 9 mg/L ozone dosage-10 min contact time alternatives resulted with the best treatment performance in terms of the removal of micropollutants, COD, TSS, and turbidity. A feasibility analysis was conducted to evaluate the best operational conditions from a techno-economic perspective and the results revealed that the unit cost for ozonation process ranged between 0.033 $/m3 and 0.043 $/m3. Additionally, considering the feasibility, 6 mg/L ozone dose – 20 min contact time combination was found as the optimum alternative. Based on the promising results obtained in this study, ozonation can be offered as a polishing step for the effluents of high-rate activated sludge systems for the improving of the effluent quality.

Improvement of local ozone phytotoxicity modelling for autochthonous grape cultivars

The grapevine is a key crop for Mediterranean environments and is both sensitive to climate warming and air pollutants, of which ozone is the most damaging to crop yield and quality. Ambient ozone effects on the grapevine have been noticed since the late fifties but risk assessments are still impaired by the lack of information concerning differences in cultivar sensitivity, and adaptation capacity to environmental factors including drought conditions. This study develops a specific parametrization for autochthonous grape cultivars within a leaf-level stomatal flux model, the DO3SE model, coupled with a meteorological and atmospheric chemical transport modelling system, the WRF-CHIMERE, by using a renowned wine producing area, the Douro wine region of Portugal, as case study. The DO3SE model parametrization introduced in this study included phenology, photosynthetic active radiation, air temperature, air vapour pressure deficit, and leaf water potential as a proxy of soil water content. The modelling experiments, which included simulations with the current default Convention on Long-Range Transboundary Air Pollution DO3SE parametrization and with the proposed parametrization, covered a reference grapevine growing season (from April to September 2017), during which a measuring campaign was carried out. Simulation results show that the proposed parametrization succeeded to replicate the observed grapevine leaf-level stomatal flux gradient in the region. Both field and modified DO3SE model values indicate that considerable areas in the Douro wine region of Portugal can exceed critical phytotoxic ozone dose (POD) values, although with a lower and different spatial extent when compared to the default DO3SE parametrization for the grapevine. However, under irrigated conditions, the POD values increase, and the values are close to those obtained with the default parametrization. Overall, the research results indicate that air quality management, in particular the reduction of ozone levels in the ambient air, must also be considered to define sustainable grape and wine production strategies in the context of climate and wine production management change.

Ozonation of lake water and wastewater: Identification of carbonous and nitrogenous carbonyl-containing oxidation byproducts by non-target screening

Ozonation of drinking water and wastewater is accompanied by the formation of disinfection byproducts (DBPs) such as low molecular weight aldehydes and ketones from the reactions of ozone with dissolved organic matter (DOM). By applying a recently developed non-target workflow, 178 carbonous and nitrogenous carbonyl compounds were detected during bench-scale ozonation of two lake waters and three secondary wastewater effluent samples and full-scale ozonation of secondary treated wastewater effluent. An overlapping subset of carbonyl compounds (20%) was detected in all water types. Moreover, wastewater effluents showed a significantly higher fraction of N-containing carbonyl compounds (30%) compared to lake water (17%). All carbonyl compounds can be classified in 5 main formation trends as a function of increasing specific ozone doses. Formation trends upon ozonation and comparison of results in presence and absence of the •OH radical scavenger DMSO in combination with kinetic and mechanistic information allowed to elucidate potential carbonyl structures. A link between the detected carbonyl compounds and their precursors was established by ozonating six model compounds (phenol, 4-ethylphenol, 4-methoxyphenol, sorbic acid, 3-buten-2-ol and acetylacetone). About one third of the detected carbonous carbonyl compounds detected in real waters was also detected by ozonating model compounds.Evaluation of the non-target analysis data revealed the identity of 15 carbonyl compounds, including hydroxylated aldehydes and ketones (e.g. hydroxyacetone, confidence level (CL) = 1), unsaturated dicarbonyls (e.g. acrolein, CL = 1; 2-butene-1,4-dial, CL = 1; 4-oxobut-2-enoic acid, CL = 2) and also a nitrogen-containing carbonyl compound (2-oxo-propanamide, CL =1).Overall, this study shows the formation of versatile carbonous and nitrogenous carbonyl compounds upon ozonation involving ozone and •OH reactions. Carbonyl compounds with unknown toxicity might be formed, and it could be demonstrated that acrolein, malondialdehyde, methyl glyoxal, 2-butene-1,4-dial and 4-oxo-pentenal are degraded during biological post-treatment.

In-situ sludge reduction based on Mn2+-catalytic ozonation conditioning: Feasibility study and microbial mechanisms

To improve the sludge conditioning efficiency without increasing the ozone dose, an in-situ sludge reduction process based on Mn2+-catalytic ozonation conditioning was proposed. Using ozone conditioning alone as a control, a lab-scale sequencing batch reactor coupled with ozonated sludge recycle was evaluated for its operating performance at an ozone dose of 75 mg O3/g VSS and 1.5 mmol/L Mn2+ addition. The results showed a 39.4% reduction in MLSS and an observed sludge yield of 0.236 kg MLSS/kg COD for the O3+Mn2+ group compared to the O3 group (15.3% and 0.292 kg MLSS/kg COD), accompanied by better COD, NH4+-N, TN and TP removal, improved effluent SS and limited impact on excess sludge properties. Subsequently, activity tests, BIOLOG ECO microplates and 16S rRNA sequencing were applied to elucidate the changing mechanisms of Mn2+-catalytic ozonation related to microbial action: (1) Dehydrogenase activity reached a higher peak. (2) Microbial utilization of total carbon sources had an elevated effect, up to approximately 18%, and metabolic levels of six carbon sources were also increased, especially for sugars and amino acids most pronounced. (3) The abundance of Defluviicoccus under the phylum Proteobacteria was enhanced to 12.0% and dominated in the sludge, they had strong hydrolytic activity and metabolic capacity. Denitrifying bacteria of the genus Ferruginibacter also showed an abundance of 7.6%, they contributed to the solubilization and reduction of sludge biomass. These results could guide researchers to further reduce ozonation conditioning costs, improve sludge management and provide theoretical support.

Changes in the Composition of Digestate Liquid Fraction after Ozone and Ultrasonic Post-Treatment

There is a growing concern about environmental pollution with digestate, which is produced in significant amounts in the anaerobic digestion process. The inappropriate application of digestate in agriculture may lead to ammonia emission to the atmosphere, nutrients infiltration to groundwater and surface waters eutrophication. There is a great interest in the development of efficient downstream technologies that will help better handle digestate. This study assessed the effect of three different disintegration methods (ozonation, ultrasonication, combination of ozonation and ultrasound) on solids content, nutrient concentration and biodegradability of the liquid fraction of sugar beet pulp digestate. The influence of initial pH (7, 8, 9), ozone dose (0.05–0.45 g O3/g TS), specific ultrasound energy (10,381–51,903 kJ/kg TS) and vibration amplitude (50, 100%) on the performance of digestate liquid fraction treatment was investigated. The highest removal efficiencies of organic substances, total and ammonia nitrogen averaging at 13.81, 20.04 and 28.70%, respectively, in separate ozonation and ultrasonication processes, was obtained at ozone dose of 0.25 g O3/g TS, specific energy of 41,522 kJ/kg TS and amplitude of 100%. The application of combined processes, first ultrasonication and then ozonation, resulted in an increase in the above-mentioned removal efficiencies to 58.16, 36.60 and 48.71%, respectively.

Effects of gaseous ozone treatment on the quality and microbial community of salmon (Salmo salar) during cold storage

To elucidate the effect of gaseous ozone with different dose and exposing time (A and B: 1 mg/m 3 or 3 mg/m 3 for 5 min; C and D: 1 or 3 mg/m 3 for 10 min, respectively, corona discharge method) on the quality of salmon, the microbial growth, lipid oxidation, color, odor characteristics, microbiota, and the correlations between them were studied. The results showed that the total viable counts of groups C (6.05 log CFU/g) and D (5.71 log CFU/g) were lower than the control (7.08 log CFU/g) on day 10. The ozone treatment also retarded the increase of total volatile basic nitrogen (TVB-N), thiobarbituric acid substances (TBARS), and drip losses as well as the decrease of sensory scores. Though the ozonated treatment led to a slight decrease of a * value, it could deodorize the fishy smell. The results of next-generation sequencing showed that the relative abundance of Photobacterium decreased after treatments, but recovered during storage, and it was the predominant bacteria causing the deterioration of salmon fillets according to the correlation analysis with sensory score, TVB-N, and TBARS values. The results demonstrated that gaseous ozone was a promising method for salmon preservation, and the exposing time had a greater effect on the salmon quality than the ozone concentrations in this study. The ozonation treatment with the dose of 1 or 3 mg/m 3 for 10 min was recommended for salmon fillets. • Photobacterium was the main bacteria causing the quality deterioration of salmon. • Gaseous ozone reduced the relative abundance of Photobacterium after treatment. • The exposing time had a greater effect on the salmon quality than the ozone dose. • The optimal ozonation treatment for salmon was 1 or 3 mg/m 3 for 10 min. • The deodorizing effect of ozone may relate to the ozonolysis of fatty acids.

THE EFFECT OF FLOW RATE AND DURATION OF OZONATION ON THE CHANGE IN THE POLARIZATION ANGLE OF VIRGIN COCONUT OIL (VCO) WITH TRANSMISSION POLARIZATION METHOD

Research on the polarization method was performed to determine the effect of ozonation on the change in the polarization angle. In the previous studies, the change in the polarization angle would be greater with the longer time of VCO ozonation. This study aimed to determine the effect and the relation of ozonation flow rate, ozonation duration, ozone dose, and viscosity on the changes in the transmission polarization angle on VCO. The sample used is VCO, which was ozonated with a constant volume and varied by its flow rates and ozonation times. The parameter measured from VCO is the change in the transmission polarization angle. Red and green diode lasers with a power of 5 mW were used as light sources. The results showed that the ozonation affects the value of the change in the polarization angle. The ozonated samples (B, C, D) has an average change in the polarization angle of 1.10° ± 0.07° (green laser) which is greater than the un-ozonated sample (A) of 0.60° ± 0.05o (green laser). The wavelength also affects the value of the change in the polarization angle of the VCO. Samples using a green laser have a greater change in the polarization angle than the red laser with an average of the change in the polarization angle in sample D are 1.50° ± 0.06° (green laser) and 1.40° ± 0.06° (red laser). The ozone dose in the sample affects the value of the change in the polarization angle. The larger the ozone dose results in the increasing value of the change in the polarization angle. The viscosity value also affects the change in the polarization angle of VCO. The greater viscosity results in the greater value of the change in the polarization angle.

Using radish (Raphanus lativus L.) germination to establish a benchmark dose for the toxicity of ozonated-petroleum byproducts in soil

The concentration-response relationship between the germination outcome of radish (Raphanus lativus L.) and ozonated petroleum residuals was determined experimentally. The outcomes were used to produce an ecological risk assessment model to predict the extra risk of adverse outcomes based on the concentration of ozonated residuals. A test soil with low organic matter (0.5% w/w) was mixed with raw crude oil, artificially weathered, and treated at three doses of ozone (O3) gas (5 g, 10 g, and 40 g O3 per 600 g of soil). Total petroleum hydrocarbons (TPH) and produced dissolved organic carbon (DOC) were measured. TREATMENT categories (control, petroleum, petroleum + 5 g O3, petroleum + 10 g O3, and petroleum + 40 g O3) were then used to create a dilution series using different proportions of the test soil and a commercially available potting mix (∼75% w/w organic matter) to evaluate the effects of background organic matter (b-ORGANIC) in conjunction with TPH and DOC. Multivariable logistic regression was performed on the adverse germination outcome as a function of TPH, DOC, TREATMENT, and b-ORGANIC. The parameters controlling germination were the continuous variable DOC and the categorical variables TREATMENT and b-ORGANIC. Radish germination was strongly harmed by DOC from ozonation, but DOC's ecotoxicity decreased with increasing O3 dose and the presence of b-ORGANIC beyond 10% (w/w). We used the germination outcome of radish to produce a logistic regression model that computes margins of DOC (± std. error) that create 10%, 25%, and 50% extra risk of adverse germination effects.

Effect of pH and Ozone Dosage on Characteristic of Ozonated Rice Bran Oil


 
 
 The influence of pH and ozone dose, as well as ascorbic acid addition during the ozonation process, on the properties of Rice Bran Oil (RBO), was examined. The spectroscopic characteristic of RBO before and after ozonation was analysis directly, while the physicochemical property was assessed by density, viscosity, pH, iodine number, peroxide number, and acid number. With an increase in ozone dose, the carbon double bond in the RBO reduced. The primary product of the ozonation process is ozonide, and one of its by-products is 1,2,4-trioxolane, which contains a carbon single bond as a result of the ozonation reaction. According to this study, the pH 4 and ozone dose of 440 mg O3/L are the optimum parameters utilized in the RBO ozonation process. RBO's density and viscosity were 0.918 g/mL and 0.042 cP, respectively, at these conditions. Its iodine number, acid number, and peroxide number were also 3.173 g/g RBO, 2.3 mg NaOH/g RBO, and 55 mgeq/kg, respectively. Analyses of gas chromatography and nuclear magnetic resonance spectroscopy revealed the presence of 1,2,4-trioxolane. Ozone dosage is critical because greater ozone concentrations place RBO in a saturated state, making the 1,2,4-trioxolane unstable and readily destroyed, whereas lower temperatures can avoid this.
 
 

Application of Ultraviolet-C Radiation and Gaseous Ozone for Microbial Inactivation on Different Materials.

With the advent of the COVID-19 pandemic, there has been a global incentive for applying environmentally sustainable and rapid sterilization methods, such as ultraviolet-C radiation (UVC) and ozonation. Material sterilization is a requirement for a variety of industries, including food, water treatment, clothing, healthcare, medical equipment, and pharmaceuticals. It becomes inevitable when devices and items like protective equipment are to be reused on/by different persons. This study presents novel findings on the performance of these sterilization methods using four microorganisms (Escherichia coli , Staphylococcus aureus , Candida albicans , and Aspergillus fumigatus) and six material substrates (stainless steel, polymethyl methacrylate, copper, surgical facemask, denim, and a cotton-polyester fabric). The combination of both ozone and UVC generally yields improved performance compared to their respective applications for the range of materials and microorganisms considered. Furthermore, the effectiveness of both UVC and ozone was higher when the fungi utilized were smeared onto the nonabsorbent materials than when 10 μL droplets were placed on the material surfaces. This dependence on the contaminating liquid surface area was not exhibited by the bacteria. This study highlights the necessity of adequate UVC and ozone dosage control as well as their synergistic and multifunctional attributes when sterilizing different materials contaminated with a wide range of microorganisms.

Bridging experimental and monitoring research for visible foliar injury as bio-indicator of ozone impacts on forests

ABSTRACT Tropospheric ozone (O3) is a phytotoxic air pollutant and the O3-induced visible foliar injury (O3 VFI) is a biomarker. A recently developed Free-air O3 eXposure (FO3X) is a promising facility to verify field-observed “O3-like” VFIs and to establish a flux-based threshold for the O3 VFI onset. The present study compared O3-like VFI registered in the southern European forest sites with actual O3 VFI observed in a FO3X experiment. The O3-like VFIs were evaluated by eye in forests and thus it was subjective. According to the imaging analysis, we firstly demonstrated that major parts of the colors were similar in the field and the FO3X. The color pallets for O3 VFI was species-specific and considered a advanced tool for the O3 VFI diagnosis. In addition, we calculated a flux-based threshold for the O3 VFI onset at the FO3X based on a Phytotoxic Ozone Dose (POD1), which ranged from 4.9 to 18.1 mmol m−2 POD1. This FO3X-derived threshold partly explained but did not necessarily match with the observation for several tree species in actual forests. The multivariate analysis showed that O3 VFI was decreased by the presence of various species and suggested the importance of continuous monitoring activities in the field for the further analysis.

The role of TiO2 NPs catalyst and packing material in removal of phenol from wastewater using an ozonized bubble column reactor

Phenol is present as a highly toxic pollutant in wastewater, and it has a dangerous impact on the environment. In the present research, the phenol removal from wastewater has been achieved using four treatment methods in a bubble column reactor (treatment by ozone only, using packed bubble column reactor with ozone, utilizing ozone with TiO2 NPs catalyst in the reactor without packing, and employing ozone with TiO2 NPs in the presence of packing). The effects of phenol concentration, ozone dosage, TiO2 NPs additions, and contact time on the phenol removal efficiency were determined. It was found that at a contact time of 30 min, the phenol removal was 60.4, 74.9, 86.0, and 100% for the first, second, third, and fourth methods, respectively. The results indicated that the phenol degradation method using catalytic ozonation in a packed bubble column with TiO2 NPs is the best treatment method. This study demonstrated the advantages of using packing materials in a bubble column reactor to enhance the mass transfer process in an ozonation reaction and then increase the phenol removal efficiency. Also, the presence of TiO2 NPs as a catalyst improves the ozonation process via the production of hydroxyl routs. Additionally, the reaction kinetics of ozonation reaction manifested that the first order model is more applicable for the reaction. Eventually, the packed bubble column reactor in the presence of TiO2 NPs catalyst provided a highperformance removal of phenol with a high economic feasibility.

Detecting industrial discharges at an advanced water reuse facility using online instrumentation and supervised machine learning binary classification

Industries occasionally discharge slugs of concentrated pollutants to municipal sewers. These industrial discharges can cause challenges at wastewater treatment plants (WWTPs) and reuse systems. For example, elevated total organic carbon that is refractory through biological wastewater treatment increases the required ozone dose, or even exceeds the capacity of the ozone unit, resulting in a treatment pause or diversion. So, alert systems are necessary for potable reuse. Machine learning has many advantages for alert systems compared to the status quo, fixed thresholds on single variables. In this study, industrial discharges were detected using supervised machine learning and hourly data from sensors within a WWTP and downstream advanced treatment facility for aquifer recharge. Thirty-five different types of machine learning models were screened based on how well they detected an industrial discharge using default tuning parameters. Six models were selected for in-depth evaluation based in their training set accuracy, testing set accuracy, or event sensitivity: Boosted Tree, Cost-Sensitive C5.0, Oblique Random Forest with Support Vector Machines, penalized logistic regression, Random Forest Rule-Based Model, and Support Vector Machines with Radial Basis Function Kernel. After optimizing the tuning parameters and variable selection, Boosted Tree had the highest testing set accuracy, 99.2%. Over the 5-day testing set, it had zero false positives and would have detected the industrial discharge in 1 h. However, setting fixed thresholds based on the maximum normal datapoint within the training set resulted in nearly as good testing set accuracy, 98.3%. Overall, this study was a successful desktop proof-of-concept for a machine learning-based alert system for potable reuse.

Determination of the Effects of Different Aqueous Ozone Doses and Temperature on Germination and Seedling Development of Vetch Seeds

ABSTRACT Various effects of ozone treatment on seed germination and development are known. This feature of ozone has gained more importance in recent years. On the other hand, it is reported that ozone used in excessive amounts causes adverse effects. The method of application of ozone and the results obtained vary according to the material used. In this study, two different vetch species (hairy vetch and common vetch), for 30 minutes four different ozone doses application [control (0.40 g/m3), 1.60 g/m3, 2.80 g/m3, 4.00 g/m3] and three different temperatures (10, 15 and 20 °C) were examined. As a result of applications; germination rate, radicle length, plumule length, seedling length, seedling fresh weight, seedling dry weight and vigor index values were calculated. It was determined that plumule length, seedling length, seedling fresh weight and vigor index values of the species were affected by ozone doses and temperature applications. Also, it was determined that the cultivar ˟ temperature ˟ ozone dose interaction had significant effects on the length of the radicle (P < 0.01) and the seedling fresh weight (P < 0.05). According to the results of the study; it has been determined that the applications of ozonized water up to 2.80 g/m3 positively affect the germination, radicle and seedling development of hairy vetch and common vetch seeds compared to the control. Besides, it was observed that the highest dose, 4.00 g/m3 dose, negatively affected the same parameters. It was found that the effect of temperature and ozone dose applications were significant on germination and seedling development.