• Journal of Korean Society of Environmental Engineers
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• v.28 no.3
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• pp.345-350
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• 2006

This study investigated the removal of recalcitrant organics in dyeing wastewater using a fluidized bed reactor(FBR) that contained cell-immobilized pellets. The pellets were manufactured and condensing the gel phase by mixing PEG-polymer and cells to form micro-porous PEG-polymer pellets whose size were ${\Phi}\;4mm{\times}H\;4mm$ on average. An industrial activated sludge without any pre-adaptation was used for the cell immobilization because it gave an equivalent removal efficiency to a pre-adapted sludges. The feed was obtained from an effluent of a biological treatment plant, which contained $SCOD_{Cr}$ of 330 mg/L and $SBOD_5$ of 20 mg/L. The $SCOD_{Cr}$ removal efficiency was over 45% and the effluent $COD_{Mn}$ concentration was less than 100 mg/L at HRTs from 6 to 24 hrs. The optimum HRT in the FBR was determined as 12 hrs considering the removal efficiency and cost. When a raw wastewater containing 768 mg/L of $COD_{Cr}$ was fed to the FBR, the effluent $COD_{Cr}$ concentration increased only slightly, giving a 70% of $COD_{Cr}$ removal or a 97% of $BCOD_5$ removal. This indicated that the FBR had an excellent capability of biodegradable organics removal also. In conclusion, the FBR could be applied to textile wastewater treatment in place of an activated sludge process.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.1
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• pp.3-8
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• 2008

• Textile Coloration and Finishing
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• v.19 no.3
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• pp.1-5
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• 2007

The advantage of enzyme scouring over alkali scouring is that the enzymatic process can be carried in a neutral pH, resulting in less damage on the fibers and a drastic reduction of wastewater. Since the pH of scouring bath is neutral, dyeing can be carried in the same bath. Four different types of scouring and dyeing in a single-bath were performed in this work: continuous scouring and dyeing in one-bath I and II, simultaneous scouring and dyeing in one-bath I and II. The difference between process I and II is the existence of an after-treatment process in the scouring. Dyeing was performed with three major colors(red, blue, yellow) and black to investigate the dye-ability. The absorbency of scoured and dyed fabrics was measured using gravimetric absorbency testing system. The fabric weight loss was measured after the treatment. Although the color depth for the three major colored fabrics treated in a single-bath was lower than the fabric scoured and dyed separately, the fabrics dyed with black did not show much difference. In addition, the absorbency of fabric treated in a single-bath was higher than the fabric treated separately.

• International Journal of Industrial Entomology and Biomaterials
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• v.47 no.1
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• pp.63-71
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• 2023

In this study, the structural characteristics of sericin recovered from wastewater released from the silk textile industry (Plant sericin) were comparatively analyzed with those of sericin extracted from a silkworm cocoon produced in a laboratory (Lab sericin). To prepare Plant sericin, ethanol was added to wastewater (i.e., a sericin aqueous solution) after the degumming process to remove nonprotein materials, affording a sericin precipitate. To prepare Lab sericin, nonprotein materials were removed from a silkworm cocoon and sericin was subsequently extracted from the cocoon. Lab sericin and Plant sericin exhibited similar solution viscosities, gel strengths, and crystallinity indices, indicative of the similar molecular weights (MWs) of the two sericin samples. In the case of sericin powder, Plant sericin was more crystalline than Lab sericin due to its treatment with ethanol. The findings of this study revealed that sericin recovered from industrial wastewater can be used equally as its MW is similar to that of sericin obtained through laboratory-scale extraction.

• Journal of Environmental Health Sciences
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• v.31 no.1
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• pp.86-93
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• 2005

Because generally large amount of sludges are generated from the process of sewage and wastewater treatment, the management and controlment of those sludge has become a important issue in many researches. In this dissertation, we conducted the research to see the physico-chemical characteristics of sludges generated from various sources. Moisture of sludges were 81.5% in textile industries, 81.4% in frame metal industries, 80.7% in 1st metal industries. Volatile solid were 22.1% in hide · rubber industries, 21.9% in coke · petroleum industries. Fixed solid were 18.5% and 17.7% in the 1st metal industries and frame metal industries. High heating value by wet base were 1,850 kcal/kg in coke · petroleum industries, 1,220 kcal/kg in hide · rubber industries, but sludges from the 1st metal industries and frame metal industries were impossible to incinerate because most of those sludges were inorganic. The leaching test showed that hazardous materials was detected in nearly every kinds of sludges. Some of sludges from hide · rubber industries and frame metal industries exceeded the leaching criteria and so they were classified as specific wastes. And other sludges generated in sewage treatment plants or other industries was below the leaching criteria.

• Journal of Industrial and Engineering Chemistry
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• v.68
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• pp.406-415
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• 2018

Here, as-synthesized $Fe_3O_4$ nanoparticles were incorporated into the zeolitic imidazolate framework (ZIF-8) lattice to activate sodium percarbonate (SPC) for degradation of methylene blue (MB). The reaction rate constant of $Fe_3O_4@ZIF-8/SPC$ process ($0.0632min^{-1}$) at acidic conditions (pH = 3) was more than six times that of the $Fe_3O_4/SPC$ system ($0.009min^{-1}$). Decreasing the solute concentration, along with increasing SPC concentration and $Fe_3O_4@ZIF-8$ nanocomposite (NC) dosage, favored the catalytic degradation of MB. The $Fe_3O_4@ZIF-8$ NC after fifteen consecutive treatment processes showed the excellent stability with a negligible drop in the efficiency of the system (<10%). The reaction pathway was obtained via GC-MS analysis.

• Journal of Microbiology and Biotechnology
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• v.23 no.10
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• pp.1460-1471
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• 2013

Microalgal biofuel production from wastewater has economic and environmental advantages. This article investigates the lipid production from high chemical oxygen demand (COD) bioethanol wastewater without dilution or additional nutrients, using a newly isolated heterotrophic microalga, Chlorella vulgaris LAM-Q. To enhance lipid accumulation, the combined effects of important operational parameters were studied via response surface methodology. The optimal conditions were found to be temperature of $22.8^{\circ}C$, initial pH of 6.7, and inoculum density of $1.2{\times}10^8cells/ml$. Under these conditions, the lipid productivity reached 195.96 mg/l/d, which was markedly higher than previously reported values in similar systems. According to the fatty acid composition, the obtained lipids were suitable feedstock for biodiesel production. Meanwhile, 61.40% of COD, 51.24% of total nitrogen, and 58.76% of total phosphorus were removed from the bioethanol wastewater during microalgal growth. In addition, 19.17% of the energy contained in the wastewater was transferred to the microalgal biomass in the fermentation process. These findings suggest that C. vulgaris LAM-Q can efficiently produce lipids from high-concentration bioethanol wastewater, and simultaneously performs wastewater treatment.

• Textile Coloration and Finishing
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• v.8 no.5
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• pp.17-24
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• 1996

Dye solutions were tested in order to find the optimal condition of ozonation and determine the progress of degradation, i.e., change of the parameters characterizing the dye solutions. From the results of our experiment we can conclude that almost all of the color was removed within a 10 minute time period. An ozone oxidation results in the effective removal of COD(60%). but the elimination of the total organic carbon(TOC) was not successful, only about 15~40% of TOC was removed from dyeing wastewater in 30 minutes. The color removal is much effective in using ozonation method.

• Textile Coloration and Finishing
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• v.10 no.6
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• pp.42-48
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• 1998

For the effective operation of complex dyeing wastewater treatment plant, the biodegradability of various dyeing agents were investigated. For experiments in biodegradability, activated sludge from aeration tank of wastewater treatment plant was used. Biodegradability of dyeing agents were compared by measuring the $BOD_5/COD_{Cr}$ ratios and $BOD_5$ removal efficiency. $COD_{Cr}$. removal efficiency of dyeing agents was less than 80% , while $BOD_5$ removal efficiency was less than 60% after of days. Therefore, biodegradation by activated sludge were found very difficult. Judging from this, it is necessary to isolate strains biodegrading dyeing agents in order to operate activated sludge process safely.

• Textile Coloration and Finishing
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• v.12 no.2
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• pp.96-102
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• 2000

For the effective treatment of dyeing-complex wastewater, the most effective chemical coagulation method was studied. For the chemical coagulation of dyeing-complex wastewater, polyferric sulfate, $4Al_2(SO_4)_3$, PAC, ferrous sulfate, ferric sulfate, $FeCl_2$ and lime were used. It was investigated that polyferric sulfate was the most efficient coagulant. The optimal conditions and results for polyferric sulfate include the followings. When initial $COD_{Mn}$ concentration was 600mg/L, the optimal initial pH, dosage of coagulant, dosage of lime and PAA for $COD_{Mn}$ removal efficiency were 5, 1,200mg/L, 500mg/L and lmg/L, respectively. The optimal dosage of polyferric sulfate was increased proportionally to the influent $COD_{Mn}$ concentration.