Papers by Keyword: Ozone

Abstract: The semiconductor industry is a significant consumer of water and chemicals. In particular, water is a valuable resource, and its efficient use is crucial to ensure availability for future generations. By implementing measures to reduce water and chemical consumption, the semiconductor industry can minimize its environmental footprint and contribute to sustainability efforts. Technology for the recycling of unused hot ultrapure water (H-UPW), ozonated water and reclaimed sulfuric acid-hydrogen peroxide mixtures (SPM) has been developed and installed in high-volume manufacturing (HVM) semiconductor manufacturing facilities. This paper presents an overview of the technology and expected savings in water, sulfuric acid and energy consumption from the implementation of these technologies.

Abstract: The paper presents studies of the process of purification of model wastewater, which contained high concentrations of animal proteins, fats and hydrocarbons. The model wastewater solution was treated by biosorption treatment in a bioreactor; with pre-ozonation (O₃) and biosorption purification in the bioreactor and in the variant with pre-treatment with ozonation and hydrogen peroxide – by the method of AOPs (O₃/H₂O₂) or the process «Peroxon». The efficiency of cleaning by chemical oxygen consumption when using the AOPs method reached (97-98) %, disinfection – up to 100 %.

Abstract: The research on phenolic compound degradation using chemical oxidation methods in a plasma reactor was performed with an Ozone-Plasma Hybrid Reactor (RHOP). This device operates by combining ozonation reactions in the liquid plasma within the reaction room. Furthermore, Ozone gas as a reagent is produced by the standard ozonator type Resun RSO-9805 made in Hong Kong and fed into this device, where the liquid phase is mixed within the injector. This way, the two-phase mixture reacts more intensively in RHOP. Also, this combination is designed to intensify hydroxyl radicals while the liquid phase is in an alkaline condition constantly exposed to plasma. The results demonstrated a continuous circulation for 2 hours at the initial concentration of 50 ppm for p-chlorophenol with a volume of 2 liters. This further obtained an 83.98% removal rate and 42.19% COD value decrease.

Abstract: The demand for vegetable consumption is essential issue to serve citizens. Excessive protective chemical elimination which is applied advanced solutions brings high effects being investigated by domestic and international scientists. In this report, research team conducted and designed the vegetable washing machine integrated with the ultrasonic power and Ozone microbubbles to wash out plentiful protective chemicals attaching to surfaces of leafy vegetables. Followingly, using Taguchi method for four kinds of vegetables including salad, water spinach, Chinese cabbage, and mustard greens verifies the effectiveness of solutions. Vegetable samples are treated soaking pool making ultrasonic wave and Ozone microbubbles raging from 1.0ppm to 2.0ppm. The practical results demonstrated that the method using the ultrasonic power and Ozone microbubbles has high effects on eradicating protective chemical on leafy vegetables.

Abstract: The tofu industries in Indonesia produce a considerable amount of liquid waste. Most of these tofu industries do not treat waste properly. Liquid waste is channeled directly to the nearest water stream, and thus the values of COD, BOD and TSS are considerably high, which can damage the aquatic ecosystems. According to the Indonesian government rule (Permen LH no.5/2014), the maximum levels of COD, BOD and TSS are 300 mg/L, 150 mg/L, and 200 mg/L. One of alternative methods to reduce these three parameters is the ozonation method. Ozone is able to break down organic components well because of its strong oxidative properties (2.07 mV) and it can decompose into OH radicals which have stronger oxidative properties (2.80 mV). The objectives of this study are to reduce the levels of COD, BOD and TSS of tofu liquid waste into below of the maximum level set by the Indonesian government rule and to study the effect of pH conditions on the effectiveness of ozonation process. Ozonation is carried out under conditions at acidic pH, alkaline pH, and neutral pH, and with a waste concentration of 10%. Ozonation is done by flowing ozone directly into the waste for 120 minutes with an interval of 30 minutes. The levels of BOD, COD, and TSS before ozonation were 1,200 mg/L, 880 mg/L and 600 mg/L. After ozonation, it was found that the levels of COD, BOD and TSS of the waste without any pre-treatment (or acidic condition) was able to be reduced by 46.6%, 44.5% and 41.6%, respectively. Whereas, in neutral conditions the decreases of COD, BOD, and TSS were about 64.3%, 67.0%, and 62.4%, respectively. Optimum ozonation was found in alkaline conditions with the decreases in COD, BOD, and TSS values were about 85.4%, 84%, and 100%, respectively.

Abstract: With the rapid economic development, pulp and paper industry has changed from resource consumption to production of clean transformation. This paper is based on the single concentration (7.4%) ozone bleaching, while prolonging the reaction time of a single variable, ozone lignin removal efficiency and the impact on the fiber. After a lot of research and experiments repeatedly found that bleaching whiteness can reach 75.5% (%ISO whiteness), with the increasing of the degree of the tear strength in the ozone bleaching time declining, and finally to 240mN. Breaking length increased first and decreased state of change can be up to 2.1445km. Pulp hardness with KMnO₄ value represents the final reach 2.65. The best bleaching time should be 150 minutes, it can be made into pulp and paper all aspects of performance to achieve the best state.

Abstract: The increases in biological mineralization of selected Metalworking fluids (MWF) pre-treated by ozone were investigated. There were studied 11 different fluids four of emulsion types, four of semi-synthetics and three of synthetic types. Expectations according to the literature review that the pre-treatment enhance the biodegradability of the metalworking fluids were not confirmed in 7 samples. Only 4 samples achieved after ozone pre-treatment better biological degradation. Enhanced biodegradability level after ozone pre-treatment step was observed in three emulsions (Samples 1, 2 and 3) and one semi-synthetics (Sample 7). While nontreated soluble oils reached biodegradability level from 45 to 73 %, after 1 hour of ozone treatment the biodegradability increased from 65 to 82 %. Semisynthetic metalworking fluid without any treatment reached 56 % of the biodegradability level. After one hour of ozone application increased the biodegradability level to 74 % and after 2 hours to 82 %. During ozone treatment it was observed the destabilization of emulsions in half of tested samples.

Abstract: The exposure of wool fabrics to light, humidity and heat are inevitable, which will accelerate their ageing, as time goes on. The exact influences of these factors were not being parallel compared and studied previously, but are very important for preparing suitable storage or display environment for wool fabrics, especially for those excavated old wools in history. Hereby, wool fabrics were treated by heat ageing, hydrothermal ageing, UV ageing and UV & ozone ageing to figure out the effects of light, humidity and heat on their physical and chemical changes resulted in the degradation of wool. The performances of the wool fabrics with different treatments were investigated by thermogravimetric analysis (TGA), angle contact test, attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray diffraction (XRD), etc. It has been found that thermal ageing resulted in the maximum yellowness of the wool fabrics. Hydrothermal ageing was most functional in decreasing the breaking strength and crystallinity of the wool fabrics. UV lighting induced significant hydrophilicity increase on the surfaces of the wools. The addition of ozone on UV lighting did not facilitate the further ageing of wool fabrics much.

Abstract: The comparison of the phase compositions and catalytic properties of the solid components of welding aerosol (SCWAs) obtained as a result of metal welding by two types of electrodes, ANO-4 and TsL‑11 was made. Their phase compositions were investigated by X-ray diffraction phase analysis, IR spectroscopy, and pH-metry. The catalytic properties of SCWAs were studied in the low-temperature reaction of ozone decomposition. Both SCWA samples were found to purify the ozone-air mixtures (OAM) from ozone at its concentration of 1 mg/m³ to the levels below the maximum permissible concentration (MPC_O3) however the protective time of SCWA-ANO-4 (50 h) was higher than that of SCWA-TsL-11 (3 h) because of the differences in their compositions

Abstract: The injection of ozone into the air mixture for a barbotage of electrolyte at anodization of an aluminum alloy D16 in 5 % aqueous solution of sulfuric acid increases final thickness of oxide coating by 45 - 53 %, and simultaneous ultrasonic affecting and bubbling of electrolyte by the ozone-aerial mixture - only on 30 - 35 %, however in the latter case microhardness and wear resistance of coating increase. The additional applying of vibration decreases thickness, microhardness and wear resistance of an oxide layer.