THE USE OF FLOTATION METHOD FOR PURIFICATION OF WASTEWATERS CONTAMINATED WITH OIL PRODUCTS

Industrial and natural wastewater is one of the factors of environmental pollution, in particular, its water basin. Among others, fuel and oil pollutants are toxic substances that cause significant harm to all living things. It is necessary to create technologies using effective methods of wastewater treatment to solve such problems. It is possible to properly select and effectively use methods of treatment taking into account the nature, condition and concentration of contaminants in wastewater. These are the issues addressed in this article. Particular attention is paid to the use of flotation as a method of purification of stable highly dispersed emulsified wastewater containing oil or fuel contaminants in the technology of this type wastewater treatment. The main objectives of the study were to evaluate the impact of parameters and flotation reagents on the efficiency of the process of purification of stable highly dispersed emulsified wastewater. Flotation of these wastewaters was carried out on a laboratory flotation installation of pneumatic type and compared with the process of wastewater settling over time. Studies have shown that for stable emulsified wastewater containing oil or fuel contaminants with a low content of highly dispersed particles of inorganic nature or a stabilizer is present in them, it is advisable to use the flotation method with flotation units of pneumatic type. Analysing the results, it should be noted that the flotation method significantly reduces the purification time of highly dispersed emulsified wastewater from 3-5 hours of their settling in settling tanks-oil traps up to 10-20 minutes by the method of pneumatic flotation, while the degree of wastewater treatment increases in at least 1.5 - 2 times depending on the presence of fuel or oil contaminants in wastewater. If the wastewater contains a stabilizer, such as a surfactant, it can be used as an effective flotation reagent in the purification of this type of wastewater by flotation, which is not suitable for the settling process.

Karakterisasi Biogas Hasil Pemurnian dengan Down-Up Purifier Termodifikasi

Biogas is a combustible gas produced from the fermentation process of organic materials by anaerobic bacteria. Biogas can be made by using a digester. A digester is a place where the process of decomposing organic matter by bacteria. The result of biogas still contains impurity gases, so that the quality of biogas is not good. Therefore, efforts to filter the gas are necessary. The purifier is a device to filter a gas. The use of purifiers in a series of digester installations aims to filter out unnecessary gases. The purpose of this research is to design a down-up purifier type biogas purification plant, to determine the changes in substrate characteristics during fermentation and conduct a gas quality test after purification. The results showed that the biogas installation type down-up purifier was designed and assembled using 150 liter drums for gas digesters and reservoirs, 1/2 inch hoses for connecting, 2 purifiers for purification and activated charcoal adsorbents. The C/N ratio is 36.37, an average substrate temperature of 28.62^oC and an average pH of 5.9. Initial and final Biological Oxygen Demand (BOD) values are 960.12 mg/l and 9.312.53 mg/l. The initial and final Chemical Oxygen Demand (COD) values are 313,500.00 mg/l and 29,100.00 mg/l. Then Total Solid (TS) decreased by 1.45% and Volatile Solid (VS) increased by 0.21%. The use of activated charcoal adsorbents in the two purifiers can reduce CO₂ gas content by 83.79% in biogas with the most optimal purification time of 60 minutes.

Efficiency of Cyperus alternifolius, Typha latifolia, and Juncus inflexus in the removal of nitrate from surface water

Nitrate is one of the most toxic and pathogenic substances in drinking water. Nitrate levels have increased significantly in groundwater and surface water because of the high usage of nitrogenous fertilizers, which have lethal effects on human health. Therefore, the removal of this toxic material from surface water is absolutely essential. The goal of this paper is to evaluate the efficiency of three aquatic plant species, called Cyperus alternifolius, Typha latifolia, and Juncus inflexus, in the removal of nitrate from surface water. This experiment has been carried out in the laboratory scale using a hydroponics method. To do this, the water samples containing nitrate were collected and evaluated before and after the treatment to see the effects of these three plants on both the nitrate removal and the pH variation of water. The results show that all the plants can remove excessive levels of nitrate from the surface water. The comparison of the results has revealed that T. latifolia plant has higher ability to remove nitrate from water than C. alternifolius and J. inflexus. It was observed that the nitrate removal efficiency of T. latifolia was 95%, J. inflexus was 85%, and C. alternifolius was 70% after 10 days. Moreover, it was observed that the pH values of the treated water have been affected by these plants. The results of this study can be employed for further improvement of surface water quality, thereby lowering water purification time and costs as well as decreasing the nitrate-related diseases significantly.

Air filtration improvement of konjac glucomannan-based aerogel air filters through physical structure design

This study presents two methods to improve the air filtration performance of konjac glucomannan (KGM)-based aerogel air filters through physical structure design by changing the pore-size distribution and the surface area, using an air purifier. Results indicated that KGM-based aerogels had a comparable filtration effect with the commercial air filter with a longer purification time. This purification time could be shortened by over 50%, by changing the pore-size distribution from large size to small size or increase the surface area with the fold structure. This should boost the development of polysaccharide-based aerogel used as the air filter.

Prediction of PM2.5 Purification Time of Air Purifier under High Elevation Angle and High Wind Speed

In order to achieve the best purification effect of PM2.5 at different personnel positions, it is necessary to study the PM2.5 purification time at different personnel positions in the room when the influence factors change, and establish a prediction model of the purification time.In this paper, air purifier and room models were established for simulation research. Purification time of air purifier at different locations in the room was taken as regression data, and multiple linear regression method was adopted to obtain the relationship between each impact factor and PM2.5 purification time, and a prediction model of PM2.5 purification time at different personnel locations in the room was proposed.The results of this study provide a theoretical basis for putting forward the whole intelligent scheme of air purifier.

The rapid “teabag” method for high-end purification of membrane proteins

Overproduction and purification of membrane proteins are generally challenging and time-consuming procedures due to low expression levels, misfolding, and low stability once extracted from the membrane. Reducing processing steps and shortening the timespan for purification represent attractive approaches to overcome some of these challenges. We have therefore compared a fast “teabag” purification method with conventional purification for five different membrane proteins (MraY, AQP10, ClC-1, PAR2 and KCC2). Notably, this new approach reduces the purification time significantly, and the quality of the purified membrane proteins is equal to or exceeds conventional methods as assessed by size exclusion chromatography, SDS-PAGE and downstream applications such as ITC, crystallization and cryo-EM. Furthermore, the method is scalable, applicable to a range of affinity resins and allows for parallelization. Consequently, the technique has the potential to substantially simplify purification efforts of membrane proteins in basic and applied sciences.

Reduction of Purification Time of Polyspecific Equine F(ab´)2 Antivenom against Scorpion Envenomation

Background and Aims: In this study we improved the purification of immunoglobulins from equine antiserum raised against the venom of 6 types of scorption species. Caprylic acid (octanoic acid), a fatty acid, was found to have no effect on the activity of the enzymes pepsin, which is used in antivenom purification to digest Fc fragment of immunoglobulins to obtain F(ab´)2. Materials and Methods: A new method was developed for the production of F(ab´)2 antivenom whereby whole equine antiserum was mixed with equal amount of 0.15 M HCl and pH 3.4 with pepsin 660 mg/L of diluted antivenom and incubated for 4 h at 37°C. After digestion the pH were brought to 4.8 with sodium hydroxide solution (1.5 M) and then 1.5% caprylic acid and 10% ammonium sulfate was added and mixed for 60 minutes and passed through filter paper. Results: Caprylic acid caused precipitation of albumin, and ammonium sulfate reduced turbidity of solution, resulting in a reduced protein load presented to the digestion enzymes culminating in substantial reductions in processing time. Conclusions: The equine F(ab´)2 obtained using these novel caprylic acid methods were comparable in terms of yield, purity and specific activity to those obtained by multi-step and time consuming conventional salt fractionation with ammonium sulfate.

Purification of Cinnamic Acid and Aporphine Alkaloids from Enicosanthellum pulchrum Twig Extract and their Biological Activities

Background: Various methods of isolating compounds from plants have been described previously, which include conventional or modern techniques. A preparative-HPLC (prep-HPLC) system has become one of the most convenient methods, with high purity compound as well as consumes less purification time. Objective: This study is intended to purify compounds from E. pulchrum twig extract using prep- HPLC technique and to test all compounds in several biological activities. Methods: Prior to purification using prep-HPLC, the twig extract was injected onto HPLC to develop the method through its chromatograms. The established method from HPLC was used to separate the constituents using prep-HPLC. Purified compounds were elucidated through NMR and MS methods as well as through comparison with previously reported data. Three different biological activities were then conducted on the compounds, including cytotoxicity, DPPH, FRAP, and disc diffusion assays. Results: Cinnamic acid (1) and two aporphine alkaloids (liridine (2) and lysicamine (3)) have been successfully purified and identified. These compounds were first isolated from Enicosanthellum pulchrum using prep-HPLC. Cytotoxic activity revealed that liridine (2) showed strong inhibition against WEHI-3B leukaemic cells of 8.7 µM after 24 h of treatment. In contrast, cinnamic acid (1) and lysicamine (3) exhibited strong inhibitions in antibacterial activity against Staphylococcus aureus, S. epidermidis, Bacillus cereus, Pasteurella multocida and B. subtilis with more than 15 mm of inhibition zone. Conclusion: These phytochemical findings exhibit three isolated compounds from twig extract of E. pulchrum with diverse biological potential to be developed as new agents.

ADVANCED PRODUCTION TECHNOLOGY OF HIGH PURITY ARABINOGALACTAN

The technology of larch wood arabinogalactan production, combined with the preparation of dihydroquercetin, has been developed. The improved process includes the following steps: extraction of larch raw material with hot water (80–90 °C) after extraction of dihydroquercetin from it; purification of the obtained extract from high-molecular impurities by ultrafiltration using a hydrophobic membrane; concentration and additional purification of the extract from low molecular weight phenolic impurities by diafiltration using a hydrophilic membrane; spray drying of the concentrate. The concentrate drying parameters are optimized. The improved technology makes it possible to obtain a product with a main substance content ≥98%, to exclude the use of imported reagents – flocculants, and, therefore, the expenses of separation from clarified extract cake and its utilization are eliminated. Undoubted advantages of the developed technology are the reduction of the purification time of the extract, as well as the ability to automate the process of AG production and realize it in a continuous mode, that increase the feasibility and economic efficiency of the process, as well as to increase the exploitation time of the hydrophilic membrane, and to reduce energy costs.