• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
• /
• pp.275-278
• /
• 2002

In this study, to increase removal efficiency of traditional electrokinetic treatment and to reduce contaminant load of wastewater that discharged through cathode compartment, enhanced electrode compartments were investigated. Hydroxide precipitation near the cathode electrode that encounter during traditional electrokinetic treatment were prevented by enhanced electrokinetic remediation test with newly invented electrode compartment. And heavy metal concentration in wastewater showed 0 ppm thus, additive post-treatment cost were not needed.

• 한국물환경학회지
• /
• 제25권1호
• /
• pp.1-6
• /
• 2009

• 펄프종이기술
• /
• 제42권4호
• /
• pp.39-44
• /
• 2010

To increase the fracture toughness of paper made of Sw-BKP, refining and kneading conditions were analyzed. Curl and kink was known to increase the strain at break and the fracture touhness. Sequence of multiple stage beating, beating load and kneading were compared. When we applied a kneading treatment using a kneader at the final step, the most of the fiber transformation such as curl and kink occurred, the more the bulk and air-permeability improved. Physical strength and TEA(tensile energy absorption) were increased higher when kneading treatment before refining than only refining treatment was performed. TEA was increased because of higher elongation. It was found that the highest fracture toughness was obtained when applying the kneading treatment to the fibers in the pre-treatment step rather than in the middle step of beating or in the final step of beating.

• 한국물환경학회지
• /
• 제28권4호
• /
• pp.505-511
• /
• 2012

While the existing sewage treatment facilities are mainly being operated by biological processes, winter-time efficiency improvement and additional phosphorus treatment equipment using chemicals have been required to follow the effluent criteria of TP (0.2, 0.3 and 0.5 mg/L for the zone of I, II and III respectively) and $BOD_5$ (5.0 mg/L) which is intensified from 2012 in Republic of Korea. We made an investigation into actual condition of biological treatment process and calculated the optimal chemical input amount by jar test of supernatant of secondary sedimentation tank to evaluate the process improvement for the intensified criteria. Ejector BAF system for removing TP, $BOD_5$ of sewage effluent was suggested. The concentration of TP from biological process is 0.3-0.8 mg/L, and the input amount of optimal chemical coagulant was above Al/P ratio of 3(1.9 mg/L as Al) to meet the criteria of TP for secondary treatment effluent. From the results of this experiment, the best Al/P ratio for Ejector BAF system was about Al/P ratio of 1, and LV of BAF process for intensified criteria of $BOD_5$ and TP was below 1.97m/hr.

• 한국환경과학회지
• /
• 제17권8호
• /
• pp.857-869
• /
• 2008

The objective of this research is to apply more scientific, quantitative methods and procedures of environmental investigation to the development of the natural environment and the improvement of the human environment during the establishment of a sewage treatment plant and special facilities using environmental accounting. This research was performed to develop a method of strategic environmental assessment on the operation of sewage treatment plant and reuse of shellfish seeding areas through the use of environmental accounting based on EMERGY evaluation. The result was applied to marine environment policy in order to evaluate the real wealth of the regional environment and economy for both the present phase and the proposed developed phase. Using results from the comparison of EMERGY indices between the present situation and future scenarios, cost benefit analysis was performed for three different scenarios: (I) construction of a new sewage treatment plant, (2) relocation and recovery of the shellfish seeding area, and (3) relocation and re-seeding of shellfish area and construction of a new sewage treatment plant. Cost-benefit ratios of the three scenarios are 1.88, 0.94, and 1.38, respectively.

• 한국의상디자인학회지
• /
• 제11권1호
• /
• pp.43-51
• /
• 2009

The cotton, wool, cotton/wool blended(80:20) and tencel fabrics were treated with low temperature oxygen or argon plasma, enzymes(cellulase or protease), or oxygen plasma-enzyme and examined for their weight loss and conditions for treatment for the environment friendly finishing. In the plasma treatment argon gas had better effect on the weight loss than oxygen gas did and the weight loss of all the fabrics was increased as increasing discharge power and discharge time. The weight loss of cotton, wool, cotton/wool blended(80:20) fabrics decreased in a large measure after 1 hr but that of tencel didn't decrease after 1 hr. In case of cellulose fibers oxygen gas plasma induced chemical functional groups on the surface of substrate more than argon gas plasma did so the weight loss of wool was larger than that of cotton, tencel fabrics in oxygen plasma-enzyme treatment. The weight loss of cotton and tencel fabrics decreased the initial stage because oxygen plasma pre-treatment caused cross linking as well as etching effect but argon plasma pre-treatment didn't. The plasma pre-treatment cleared the way for enzyme treatment on the whole but oxygen plasma pre-treatment bear in hand the increase of weight loss more or less because of the cross linking on the surface of cellulose fibers. The appropriate conditions for plasma treatment was 10-1Torr, 40W for 30minutes and for cellulase treatment were enzyme concentration of $3g/{\ell}$, pH 5, $60^{\circ}C$ for 1hr and for protease treatment were enzyme concentration of $4g/{\ell}$ pH 8, $60^{\circ}C$ for 1hr.

• 펄프종이기술
• /
• 제41권5호
• /
• pp.15-19
• /
• 2009

Ammonia soaking treatment was introduced for hemp woody core pretreatment to increase enzymatic saccharification of polysaccharides. Portions of the xylan, cellulose, and lignin were removed by aqueous ammonia soaking, which improved the enzymatic saccharification of cellulose and xylan. Following ammonia soaking, 37% ($50^{\circ}C$-6 day treatment) to 61% ($90^{\circ}C$-16 h treatment) of the cellulose was converted to glucose and 33% ($50^{\circ}C$-6 day treatment) to 48% ($90^{\circ}C$-16 h treatment) of the xylan to xylose. Cellulose responded better to enzymatic saccharification than did xylan after the ammonia soaking treatment. Aqueous ammonia soaking pretreatment was more effective than electron beam irradiation for increasing enzymatic saccharification of xylan and cellulose in hemp woody core.

• 한국물환경학회지
• /
• 제28권6호
• /
• pp.851-858
• /
• 2012

This study conducted a result analysis on operation of 26 Rural Community Sewage Treatment Plant (RCSTP) newly constructed in Yeong-yang, Bong-hwa and An-dong areas which are located at the upper region of An-dong Dam and Im-ha Dam. Based on operation result, an analysis on characteristics of sewage in each area and the treatment efficiency of the installed treatment process was conducted. The result of analysis on characteristics of sewage has shown the difference in concentration of the sewage according to area characteristics. Sewage in areas with frequent occurrence of agricultural water and livestock wastewater had high concentration. It is important to select the most suitable treatment process when selecting a treatment process for RCSTP according to properties of sewage in each area. As a result of operation, the disposal efficiency for organic matter and suspended solids was stable with less fluctuation, but the disposal efficiency for nitrogen and phosphorus showed high fluctuation. This signifies that it is necessary to pay attention to operation condition management of nitrogen and phosphorus when operating RCSTP.

• 한국작물학회:학술대회논문집
• /
• 한국작물학회 2017년도 9th Asian Crop Science Association conference
• /
• pp.318-318
• /
• 2017

This study was conducted to find optimum mixed sowing ratio of green manure crops to reduce the use of chemical fertilizer as well as to increase the crop yield potential which will foster the utilization of green manure crops in the upland field in view of environment friendly agriculture. According to the study, the mixed ratio, 50:50, of hairy vetch and green barley showed highest nitrogen production yield in the soil due to the relatively higher organic nitrogen supply from the hairy vetch plant as well as nitrogen fixation from the air rather than other mixed ratio. In the 50:50 mixed ratio of hairy vetch and green barely total nitrogen amount in the soil showed 17.2kg per 10a, but in the other treatment ratio such as 75:25, 25:75. total nitrogen fixation amount were 16.7, 16.9 respectively. We also conducted the experiment to compare the effect of the mixed sowing treatment of green manure crops on the production of corn cultivated as a succeeding plant of hairy vetch. According to the result, the mixed ratio, 50:50, of hairy vetch and green barley treatment showed highest yield potential of corn as 153kg per 10a in seed weight which is due to the relatively higher organic nitrogen supply from the hairy vetch plant as well as nitrogen fixation from the air rather than other mixed ratio. In the mixed sowing treatment of hairy vetch 100 and barley 0 ratio, the corn production showed 148kg per 10a which is 5kg lower than that of hairy vetch 50 and barley 50 ratio, but showed statistically no difference between those two treatment. Otherwise, different treatments, such as hairy vetch 75 and barley 25, 25 and 75, 0 and 100 showed statistically different each other. Therefore, it was concluded that green manure crops, such as hairy vetch, green barley and rye were very effective crops to increase the soil fertility and gave the positive effect to the crops to give vegetative and propagative growth condition and, in turn, increased the yield potential. We have to make policy to enhance the utility of green manure crops in the upland crops as well as faddy field for the soil fertility and crop yield production which will guarantee prominent quality of environment friendly agriculture products.

• 한국물환경학회지
• /
• 제21권2호
• /
• pp.132-140
• /
• 2005

The pilot test of a new alternative for small wastewater treatment system has been conducted for two years. It consists of a hybrid bioreactor and the expert system including the process control logic, PLC system, and HMI for the process automation. In order to monitor and remote control its status, the real-time data was transferred from the on-site control center to the central station via a wireless local area network. More efficient and stable performances were observed at automatic operating mode compared with the manual. On an average, COD, SS, T-N and T-P concentrations in the effluent from the hybrid bioreactor were less than 14, 7, 12 and 0.9 mg/L, respectively. According to the result from pilot tests, the quality of treated wastewater with sand filtration was enough to be utilized again.