• Title/Summary/Keyword: Tertiary Treatment

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Development of Biological Filtration Process for Effective Nitrogen Removal and its Control strategies in Tertiary Treatment of Sewage (생물막 여과반응기를 이용한 고도질소 제거를 위한 운전제어법 개발)

  • Jeong, Jin-Woo;Kim, Sung-Won;Tsuno, Hiroshi
    • Journal of Korean Society on Water Environment
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    • v.22 no.2
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    • pp.230-237
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    • 2006
  • The operational parameters and control strategies of a tertiary wastewater treatment process a biological filtration system were investigated. The biological filtration system consisted of a nitrification filter (Fiter 1) and a polishing filter with anoxic and aerobic parts (Filter 2). SS, T-C-BOD, and T-N in effluent were kept stable at less than 3, 5 mg/L, and 5 mgN/L, respectively, under a HRT in Filter (filter-bed) of 0.37~2.3 h. T-N at the outlet of Filter 2 were about 1~5 mgN/L under the condition of LV of 50~202 m/d. Methanol addition was controlled based on the COD/N ratio or McCarty's equation. Constant COD/N ratio control results in excess addition under large diurnal fluctuation of $NOx^--N$, and McCarty's equation can be used to add appropriate amount of methanol. Control of methanol addition by on-line nitrate measurement, control of aeration by on-line DO measurement, and control of backwashing by head loss measurement are successfully operated. These results proved that this process prove the easy-maintenance and cost-effectively treatment is attainable.

Effect of the Tertiary Recrystallization on the Magnetic Properties of High Silicon Iron (고규소철 강판의 자기적 특성에 미치는 3차 재결정의 영향)

  • Koo, J.M.
    • Journal of the Korean Society for Heat Treatment
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    • v.10 no.4
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    • pp.246-254
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    • 1997
  • The 6.5wt %Si-Fe alloy sheets were made by the twin roll process. The magnetic properties and microstructures of sheets annealed in the sulfur atmosphere were studied. In the as-prepared sheet, non-oriented columnar grains about $10{\mu}m$ in diameter were observed, which grew from the surface to the inner part of the sheet. When the annealing temperature was around $700^{\circ}C$, the primary recrystallization was formed around the middle part of the sheet thickness, and the grain size increased with increasing annealing temperature. At the annealing temperature of $900^{\circ}C$, the grain size became $30{\sim}40{\mu}m$. Around the annealing temperature, the motive force of the grain growth is the grain boundary energy. However, above $1000^{\circ}C$ the surface energy played an important role in the observed grain growth. When the sheet were annealed at $1200^{\circ}C$, the grains whose (100) planes were paralled to the thin plate surface grew, and all sheet surfaces were covered with these grains after 1 hour annealing. This phenomenon is called tertiary recrystallization. A difference in surface energy between (100) and (110) surfaces provides a driving force for growth of tertiary grains. The coercive force was 0.27 mOe and the AC core loss $W_{12/50}$ was 0.38w/kg for the 6.5wt%Si-Fe alloy.

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Nutrient removal from secondary effluent using filamentous algae in raceway ponds

  • Min, Kyung-Jin;Lee, Jongkeun;Cha, Ho-Young;Park, Ki Young
    • Membrane and Water Treatment
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    • v.10 no.3
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    • pp.191-199
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    • 2019
  • In this study, we investigated the cultivation possibility using Hydrodictyon reticulatum in a continuous raceway pond as a tertiary sewage treatment plant. The cultivation possibility was evaluated by varying the light quantity, wavelength, and hydraulic retention time (HRT). Experimental results showed that the growth rates of algae and the removal efficiencies of nutrients increased as the light quantity increased, and the maximum photosynthetic rate was maintained at $100{\mu}mol/m^2{\cdot}s$ or higher. When wavelength was varied, nutrient removal efficiency and growth rate increased in the following order: green light, red light, white light, and blue light. The nutrient removal efficiencies and algae productivity in HRT 4 d were better than in HRT 8 d. We conclude that if Hydrodictyon reticulatum is cultivated in a raceway pond and used as a tertiary treatment facility in a sewage treatment plant, nutrients can be effectively removed, and production costs can be reduced.

Performance Evaluation of Tertiary Post-denitrification Processes for the Reuse of Secondary Effluent from Wastewater Treatment Plant (하수2차처리수의 재이용을 위한 후탈질공정의 평가)

  • Lee, Chanho;Yun, Zuwhan;Yi, Yun Seok;Lee, Han Saem;Ahn, Dong Keun
    • Journal of Korean Society on Water Environment
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    • v.23 no.5
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    • pp.642-649
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    • 2007
  • The effectiveness of add-on tertiary treatment processes for the polishing of the effluent of a biological nutrient removal (BNR) system from a modified $A^2/O$ process has been examined under the field condition with pilot-scale plants. The add-on treatment processes of 1) combined biofilm anoxic reactor and sand filtration, and 2) two-stage denitrification filter had been operated with various operating conditions. The experimental results indicated that two-stage denitrification filter could produced a better polished tertiary effluent. Filtration rate of $150m^3/m^2{\cdot}d$ for the 2-stage denitrifying filter could decrease the nitrate removal probably due to shorter detention time that caused insufficient reaction for denitrification. Two stage denitrification filter operated with M/N ratio of 3.0 and filtration rate of $100m^3/m^2{\cdot}d$ produced the tertiary effluent with nitrate and SS concentraitons of 2.8 mg/L and 2.3 mg/L, respectively. When the operating temperature reduced $30^{\circ}C$ to $18^{\circ}C$, $NO_3{^-}-N$ removal efficiency decreased from 73% to 68%.

Long Term Assessment of Outcome of Essential Competencies in CPPE at Tertiary and Secondary Hospitals Located in Seoul and Gyeonggi-do: College of Pharmacy Students' Evaluation from 2014 to 2018 (서울과 경기도 소재 상급종합병원과 종합병원의 필수실무실습 핵심역량교육 성과에 대한 장기적인 고찰)

  • Chun, Pusoon;Sin, Hye Yeon
    • Korean Journal of Clinical Pharmacy
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    • v.28 no.4
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    • pp.300-307
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    • 2018
  • Objective: As the demands of healthcare environment change, it is necessary to advance human health care by improving students' essential competencies including knowledge, skills, abilities, inter-professional collaboration and patient centered care. This study identified long term accomplishment and improvement of the essential competencies in clinical pharmacy practice education (CPPE) at Korean hospitals over time. Methods: This study was conducted for pharmacy students who completed CPPE evaluation related to tertiary hospitals and secondary hospitals located in Seoul and Gyeonggi-do regional area from 2014 to 2018. Results: Over the past 5 years, overall results of student evaluation on the essential competencies in CPPE at both tertiary and secondary hospitals showed a decreasing trend or did not change. Essential competency in CPPE at tertiary hospitals had been identified as superior on 'Learn clinical knowledge in the treatment of diseases' to secondary hospitals [average number of students (%): 210 (72.9%) vs 68 (68.0%)]. On the other hand, essential competencies in CPPE at secondary hospitals had been identified as better at 'inter-professionals collaborative teamwork and direct patient care' than tertiary hospitals [average number of students (%): 64 (64.0%) and 56 (56.0%) vs 121 (42.0%) and 90 (31.3%)]. A total of 176 (61.1%) students in tertiary hospitals and 66 (66.0%) in secondary hospitals evaluated that 'patient-centered care' education was good. Conclusion: In tertiary hospitals, all six essential competency outcomes have not been improved, whereas four essential competency outcomes showed an increasing trend in secondary hospitals. It will be necessary to develop outcome-based CPPE education program to better reflect the essential competencies.

Cost of Treatment for Cancer: Experiences of Patients in Public Hospitals in India

  • Nair, Kesavan Sreekantan;Raj, Sherin;Tiwari, Vijay Kumar;Piang, Lam Khan
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.9
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    • pp.5049-5054
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    • 2013
  • Background: To assess the treatment pattern and expenditure incurred by cancer patients undergoing treatment at government tertiary hospitals in India. Materials and Methods: A cross-sectional study of 508 cancer patients randomly selected from tertiary cancer hospitals funded by central/state governments located in major cities of five states in India, namely Kerala, Maharashtra, Rajasthan, West Bengal and Mizoram, during March - May 2011 was conducted. Information related to direct costs, indirect costs and opportunity costs incurred on investigations and treatment, major source of payment and difficulties faced by patients during the course of treatment was collected. Results: About 45% of the patients used private health facilities as the first point of contact for cancer related diseases as against 32% in public hospitals. About 47% sought private health facilities for cancer investigations, 21% at district/sub-district hospitals, and about 4% contacted primary health care facilities. A majority of the patients (76%) faced financial problems while undergoing treatment. Conclusions: The results highlight the importance of involving the primary health care system in the cancer prevention activities.

Tertiary Treatment of Municipal Wastewater Using Unsaturated Sandy Soil (불포화 사질토양을 이용한 도시하수의 3차 처리)

  • Kim, Seung-Hyun;Chung, Jong-Bae;Ha, Hyun-Soo;Prasher, Shiv O.
    • Korean Journal of Environmental Agriculture
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    • v.22 no.2
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    • pp.111-117
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    • 2003
  • Treatment of secondary effluent was investigated using sandy soil as a possible alternative to the tertiary treatment of municipal wastewater. Secondary effluent was applied with three different flow rates to the surface of pilot scaled lysimeters, which were filled with sandy soil. Some of the lysimeters were covered with osd, while others were kept bare in order to investigate the role of plantation on the treatment. The concentration changes in COD and nitrogen were measured along the unsaturated soil depth. The same set of experiment as with the secondary effluent was performed using tap water to investigate the dissolution of the contaminants from the soil. from the results it was found that when sandy soil was used for tertiary treatment of municipal wastewater COD removal efficiency reached about 70% regardless of the application rate. The soil depth needed to obtain such efficiency increased along with the application rate, which was about 60 cm at the application rate of 50 L/day. Results also showed that nitrification occurred rapidly. The process was completed in soil depth of first $10{\sim}20\;cm$. Nitrogen removal efficiency was as low as about 20% regardless of the application rate. Some supplementary means should be considered to improve the efficiency. Sod on the soil surface had no significant influence on the contaminant treatment but was helpful to keep the infiltration rate undiminished. Finally, the organic soil was found to release significant amount of contaminants when it was in contact with soil water.

Development and Analysis of System Dynamics Model for Predicting on the Effect of Patient Transfer Counseling with Nurses (간호사의 전원상담 효과 예측을 위한 시스템다이내믹스 모델 개발 및 분석)

  • Byun, Hye Min;Yun, Eun Kyoung
    • Journal of Korean Academy of Nursing
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    • v.48 no.5
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    • pp.554-564
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    • 2018
  • Purpose: This study aimed to construct a management model for patient transfer in a multilevel healthcare system and to predict the effect of counseling with nurses on the patient transfer process. Methods: Data were collected from the electronic medical records of 20,400 patients using the referral system in a tertiary hospital in Seoul from May 2015 to April 2017. The data were analyzed using system dynamics methodology. Results: The rates of patients who were referred to a tertiary hospital, continued treatment, and were terminated treatment at a tertiary hospital were affected by the management fee and nursing staffing in a referral center that provided patient transfer counseling. Nursing staffing in a referral center had direct influence on the range of increase or decrease in the rates, whereas the management fee had direct influence on time. They were nonlinear relations that converged the value within a certain period. Conclusion: The management fee and nursing staffing in a referral center affect patient transfer counseling, and can improve the patient transfer process. Our findings suggest that nurses play an important role in ensuring smooth transitions between clinics and hospitals.

Characteristics of Long-term Care Patients at a Tertiary Referral Hospital and Factors Influencing the Decision of prolonged Care-giving (일 상급종합병원 장기재원환자의 특성과 전원 결정 여부에 영향을 미치는 요인)

  • Lee, MiJin
    • Journal of Korean Academic Society of Home Health Care Nursing
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    • v.31 no.1
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    • pp.56-65
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    • 2024
  • Purpose: This study aimed to explore the association between demographic characteristics, hospitalization-related characteristics, and the severity of long-term hospitalization in a high-level general hospital, and to analyze the factors influencing decisions of all patients. Methods: General and clinical characteristics of the participants were analyzed using frequency, percentage, mean, and standard deviation. Differences in these characteristics, contingent upon whether a power source was requested, were analyzed using independent t-Test and Chi-squared tests. Logistic regression analysis was used to identify the factors related to the presence or absence of power requests. Results: The factors impacting the decision to refer a dependent variable include medical treatment (neurosurgery) (B=2.118, SE=0.960, p-value=.027, OR=8.314, 95% CI=1.267-54.551), infection isolation (CRE) (B=1.336, SE=0.666, p-value=.045, OR=3.804, 95% CI=1.032-14.021), and the utilization of tertiary antibiotics (B=3.076, SE=1.362, p-value= .024, OR=21.663, 95% CI=1.502-312.530). Conclusion: This study found a significant association between medical treatment (neurosurgery), infection isolation (CRE), and the use of tertiary antibiotics as dependent variables. These findings indicate that continuous monitoring can contribute to a reduction in long-term financial burdens.