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In this paper, degradation of methylene blue in aqueous solution by combination of micro/nano bubbles (MNBs) with conventional oxidation treatment i.e. Ozone and Hydrogen Peroxide (H2O2) was examined. The treatment was performed by four experimental model using macro ozone as the control treatment. The treatment system including fine bubbles produced by (FBs) generator with power consumption of 125 watt, ozone generator (production of 400 mg/h), and hydrogen peroxide (H2O2 30%) solution with concentration 10 ppm. The samples were analyzed every 15 minutes during 2 h with turbidity meter. The results show that the potential degradation of Methylene Blue with higher residual turbidity obtained from H2O2 assisted air fine bubbles + macro ozone treatment in short time after 60 minutes of treatment. The result indicated the degradation of methylene blue finely divided into organic and inorganic matter and to be absorbed of light. On the other hand, macro ozone can degradation of methylene after 180 minutes of treatment and produce less residual turbidity. [ABSTRACT FROM AUTHOR]

Water is one of the most elements of life. As the population of the world has increased, our sources of clean water have decreased. Handling a clean water quality is one of the key challenges to avoid the scarcity of clean water, included for aquaculture system. This paper reports the effect of using fine bubbles for handling aquaculture wastewater treatment plant (WWTP). The integration of fine bubbles (FBs) generator on WWTP system is a promising method for generating fine bubbles and its ability to improve water quality parameters such as dissolved oxygen (DO), turbidity, TDS, and pH level. The performance of WWTP system using fine bubbles was tested for 5 days and the experimental results showed that WWTP system can increase dissolved oxygen from 4.5 mg/L to 7.9 mg/L. It can reduce turbidity levels from 35 NTU to 11 NTU and reduce the TDS level from 124.9 ppm to 101.5 ppm. Based on the experimental results, the application of fine bubbles technology potentially to improves the performance of WWTP system, including for developing an aquaculture system. [ABSTRACT FROM AUTHOR]

This study has been investigated the mass ratio effect of chitosan and sodium tripolyphosphate in the ionic gelation method to produce fine chitosan suspension. In addition, the introduced of Lab-scale beads milling using 0.08 to 0.12 mm yttrium stabilized zirconia and applied the food-grade surfactant to obtain well-dispersed particles. The suspension was characterized by particle size analyzer, FT-IR spectroscopy, and SEM. The results show that the increase in mass ratio Cs/TPP could be gradually decreasing of size based on mean size distribution. After beads milling proses and addition of tween 80 as the surfactant, the morphology of Cs/TPP can breakdown of large particles into downsizing agglomerated particles with the solid surface. It was found that the beads milling process can be applied to prepare fine Cs/TPP suspension by proper adjustment of surfactant. [ABSTRACT FROM AUTHOR]

The efficiency and productivity of aquaculture strongly depends on the development of advanced technology for water quality management system. The most important factor for the success of intensive aquaculture system is controlling the water quality of fish rearing media. This paper reports the design of fine bubbles (FBs) generator and performance evaluation of the system to improve water quality in thai catfish media (10 g/ind) with density (16.66 ind./L). The FBs generator was designed to control the size distribution of bubble by controlling its air flow rate entry to the mixing chamber of the generator. The performance of the system was evaluated based on the produced debit, dissolved oxygen rate and ammonia content in the catfish medium. The size distribution was observed by using a high speed camera image followed by processing using ImageJ. freeware application. The results show that air flow rate 0.05 L/min and 0.1 L/min received average bubble size of 29 µm and 31 µm respectively. The generator produced bubbles with capacity of 6 L/min and dissolved oxygen rate 0.2 ppm/min/L. The obtained DO growth was 0.455 ppm/second/L while the average decay rate was 0.20 ppm/second/L. (0.011/0.005 fold). In contrast, the recieved DO growth rate is faster compared to the DO consumption rate of the Thai catfish. This results indicated that the potential application of FBs enhanced the density of thai catfish seed rearing. In addition, ammonia can be reduced at 0.0358 ppm/hour/L and it is also observed that the inhibition of bacterial growth of air FBs is postive to Aeromonas hydrophila bacteria compared to the negative control. It is concluded that as-developed FBs system can be potentially applied for intensive thai catfish culture and expected to improve the feeding efficiency rate. [ABSTRACT FROM AUTHOR]

This research aimed to produce fine chitosan particles from a crab shell waste by beads-milling method by two different concentration of PEG as dispersing agent (150 and 300 wt. %). The characterization was performed to obtain the size and size distribution, the characteristics of functional groups and the degree of deacetylation. The results showed that the chitosan fine particles was obtained with a milling time 120 minutes with the best concentration of PEG 400 150 wt. %. The average particle size of the as-prepared suspension is 584 nm after addition of acetic acid solution (1%, v/v). Beads milling process did not change the glucosamine and N-acetylglucosamine content on chitosan structure which is indicated by degree of deacetylation higher than 70%. It was concluded that beads milling process can be applied to prepare chitosan fineparticles by proper adjustment in the milling time, pH and dosage of dispersing agent. [ABSTRACT FROM AUTHOR]