http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
조순행 ( Soon Haing Cho ),이병진 ( Byung Jin Lee ) 한국폐기물자원순환학회(구 한국폐기물학회) 2002 한국폐기물자원순환학회지 Vol.19 No.1
The objectives of this study were to examine the applicability of ammonia stripping process for the removal of highly concentrated ammonia nitrogen in the wafer cleaning wastewater from semiconductor producing procedure and to recover removed ammonia nitrogen in the consideration of natural resource recycle. Also, the capital cost and operating cost was reviewed to suggest the optimal operation condition of ammonia stripping according to changes in the operation conditions. Using Ca(OH)2 for pH control of wastewater was superior economically to use off NaOH and ammonia stripping was possible without removal of sludge. The optimal pH of ammonia stripping was 10.5. The ammonia nitrogen was removed rapidly along with increasing reaction temperature and air flow rate. The reaction time to satisfy 800 mg NH3-N/L was 4, 2.3, 1.4, 0.9hrs at 25, 35, 45 and 55℃, respectively, with the air flow rate of 20L/min. In addition, H2O2 was removed completely, about 95% of organic nitrogen was removed, and up to 81.2% of ammonia nitrogen was recovered by ammonia stripping process. Capital cost and operating cost also were decreased along with the increased reaction temperature and air input. In conclusion, the ammonia stripping process was very efficient in the treatment of highly concentrated nitrogen in wafer cleaning wastewater and the optimal operating condition of ammonia stripping was at pH of 10.5 and temperature of 55℃ with air flow rate of 20L/min among applied operation conditions.
남한강 실측자와의 통계적 비교를 근거로 한 수질예측모형의 적용성 평가
오경미,조순행,유희찬 ( Kyoung Mee Oh,Soon Haing Cho,Hee Chan Yoo ) 한국물환경학회 1995 한국물환경학회지 Vol.11 No.4
The purpose of this study is to investigate the applicability of water quality models which are commonly used for evaluation and prediction of water quality of stream and rivers in Korea. Three models, QUAL2E, WASP4 and STREAM, were used for comparison. Three different statistical methods were used to test the correlation between predicted results by model and field measurements. Field data were obtained from the south branch of Han River in between Chungju and Yangpyung. Parameters used for model comparison were DO, BOD, NH₃-N, NO₃-N, Org-P and Dis-P. The data predicted by QUAL2E generally showed better fit to the field data. However, this model can not predict the effect of highly polluted stream. Nitrogen and phosphorus data predicted by WASP4 were closer to the field data than those data predicted by other models, even though more input data were required to run WASP4. The main features of STREAM are ; 1) it can predict the change of DO concentration by bottom rooted plant and by denitrification. 2) it can be applied to predict the water quality of small stream rather than large river. From this study, it was found that all three models showed poor ability in predicting water quality change caused by nonpoint discharge.