• Title/Summary/Keyword: UF

Search Result 527, Processing Time 0.026 seconds

Effect of Operating Conditions on the Fouling of UF Membrane in Treatment of Dissolved Organic Matter (UF를 이용한 용존성 유기물질 제거시 운전조건이 파울링에 미치는 영향)

  • Kwon, Eun-Mi;Yu, Myong-Jin
    • Journal of Korean Society of Environmental Engineers
    • /
    • v.22 no.7
    • /
    • pp.1183-1191
    • /
    • 2000
  • Operating conditions for reduction of membrane fouling in treatment of dissolved organic matter by UF membrane process were investigated by pilot-scale plant using various operating conditions. As inlet pressure increased, increament of transmembrane pressure and flux decline were faster. The reason was due to the increase in adsorption of dissolved organic matter and the development of cake layer compression on the membrane surface. When efficient pressure (the difference of pressure between backwash and transmembrane pressures) was high, small amount of pollutant was retained on the membrane surface. When backwash was frequently conducted, low concentration of pollutant was maintained in recycling water. Therefore, backwash could be efficiently conducted with high efficient pressure and high frequency. Fouling rate was correlated with backwash and inlet pressures, recovery rate and cumulative permeated volume. Among the operating parameters backwash pressure was most closely related to fouling rate and inlet pressure was next to backwash pressure. It seems that the fouling was strongly related to pressure which leads to the cake layer compression and adsorption of dissolved organic matter.

  • PDF

Effect of Ultrafiltration on the Components of Sesame Protein Concentrates (한외여과가 참깨박 농축단백질의 성분에 미치는 영향)

  • Jeon, Jeong-Ryae;Park, Jyung-Rewng;Kim, Jin;Yoon, See-Hye
    • Journal of the East Asian Society of Dietary Life
    • /
    • v.5 no.2
    • /
    • pp.63-71
    • /
    • 1995
  • Defatted sesame flour is the by-products obtained after oil extracting process. Although this flour has high quality and quantity of protein its use is limited only for animal feed and fertilization. Sesame seeds contain antinutrients such as oxalate, phytate and phenol compounds and these compounds lower their nutritive value. recently, ultrafiltration(UF) has been used to concentrate protein from various food sources. This study was carried out to examine the effects of UF with different membrane pore size on the components of sesame protein concentrates including antinutrients and to compare with that of conventional acid-precipitated sesame protein isolate. The protein contents of sesame protein concentrates prepared by JF using 10K, 30K, 100K were 84.2%, 82.7%, 76.4% and the protein yields were 36.44%, 34.69, 31.43% and the protein contents was 88.7% Alkali extraction process at pH 9.0 followed by UF technique reduced oxalate and phytate content. There were 85% and 94% reduction of oxalate and phytate content by UF with membrane pore size of 100K daltons, respectively. However, the content of total phenol compounds was not reduced by this method. About 99% of calcium and 50% of zinc were removed by UF with membrane of 100K daltons. total essential amino acid contents of sesame protein concentrates prepared by UF were decreased slightly when compared with acid-precipitated sesame protein concentrate.

  • PDF

A Study on the Adaptation of Korean diet and Utilization of University Foodservice According to the Nationality of International Students in Busan (부산지역 외국인 유학생의 국적에 따른 한국 식생활 적응도 및 대학급식소 이용행태 조사)

  • Hong, Kyung Hee;Lee, Hyun Sook
    • Journal of the Korean Society of Food Culture
    • /
    • v.34 no.5
    • /
    • pp.553-566
    • /
    • 2019
  • This study was undertaken to examine the dietary adaptation in Korea, and utilization of university foodservice (UF), according to the nationality of foreign students. The survey was conducted from April to June in 2017, and included 604 subjects studying in a university in Busan. The questionnaire was designed to examine the adaptability to Korean food and the consumption of UF. The nationalities included students from China (63.4%), Vietnam (13.2%), Central Asia (8.9%), Southeast Asia (5.0%), and others (9.4%). Vietnamese and Southeast Asians showed higher adaptation to Korean food than Chinese or Central Asians. The degree of contribution of UF to diet was highest amongst the Chinese, followed by Vietnamese. The main reason for not consuming UF for the Chinese and Southeast Asians was 'lack of menu variety', and for Central Asians was 'no menu that can be eaten, including due to religious reasons'. In order to improve UF, all groups asked for increased 'variety of menu', and Vietnamese and Southeast Asians also asked for 'decrease in price'. In meat, fish, and vegetable menus, there were significant differences in the types and recipes of foods preferred, as per the nationality. These results indicate that different approaches by considering the national characteristics are required, to help international students adapt to Korean food, and to increase their consumption of UF.

Removal Characteristics of Boron and Humic Acid by Pre-blending Seawater and Brackish Water Using UF-SWRO Hybrid Process in Pilot-scale Plant for Desalination (UF-SWRO 혼합공정을 이용한 해수담수화 파일럿 플랜트에서의 해수와 기수의 블렌딩을 통한 보론 및 휴믹산 제거 특성)

  • Kim, Won-Kyu;Shin, Sung-Hoon;Lee, Haksu;Woo, Dal-Sik
    • Journal of Korean Society of Environmental Engineers
    • /
    • v.38 no.1
    • /
    • pp.34-41
    • /
    • 2016
  • Using UF-SWRO hybrid process, pre-blending tests of seawater and brackish water were performed to investigate the effects on removal of boron and humic acid (HA). Feedwater pre-blending was set based on TDS concentration from 15,000 mg/L to 27,000 mg/L and analyzed for boron removal characteristics. Also organics rejection at same TDS concentration range was investigated by injecting HA. Boron concentration appeared to be high as TDS concentration was high ranging from 76.60% to 83.27%, but boron concentration in final produced water was increased up to 0.69 mg/L from 0.48 mg/L. In cases of HA tests at 10 mg/L, 22,500 mg/L TDS appeared to be higher removal rate of 17.59% than a very poor result of 8.43% in 27,000 mg/L. But high HA removal rate of 57.14% was obtained in produced water with 22,500 mg/L TDS containing 10 mg/L of HA and 27,000 mg/L TDS yielded lower boron removal rate of 54.49%. Meanwhile it was found that a relatively high flux and recovery rate were obtained following process when feedwater was injected with HA. It is considered that most of fouling substances were eliminated by binding between HA and $Ca^{2+}$. Thus, when desalination using UF-SWRO with respect to boron and HA, TDS concentration is determined to be advantageous as lower.

Polycyclic Aromatic Hydrocarbon (PAH) Binding to Dissolved Humic Substances (HS): Size Exclusion Effect

  • Hur, Jin
    • Journal of Soil and Groundwater Environment
    • /
    • v.9 no.3
    • /
    • pp.12-19
    • /
    • 2004
  • Binding mechanisms of polycyclic aromatic hydrocarbons (PAHs) with a purified Aldrich humic acid (PAHA) and its ultrafiltration (UF) size fractions were investigated. Organic carbon normalized binding coefficient ($K_oc$) values were estimated by both a conventional Stern-Volmer fluorescence quenching technique and a modified fluorescence quenching method. Pyrene $K_oc$ values depended on PAHA concentration as well as freely dissolved pyrene concentration. Such nonlinear sorption-type behaviors suggested the existence of specific interactions. Smaller molecular size PAH (naphthalene) exhibited higher $K_oc$ value with medium-size PAHA UF fractions whereas larger size PAH (pyrene) had higher extent of binding with larger PAHA UF fractions. The inconsistent observation for naphthalene versus pyrene was well explained by size exclusion effect, one of the previously suggested specific mechanisms for PAH binding. In general, the extent of pyrene binding increased with lower pH likely due to the neutralization of acidic functional groups in HS and the subsequent increase in hydrophobic HS region. However, pyrene $K_oc$ results with a large UF fraction (>100K Da) corroborated the existence of the size exclusion effect as demonstrated by an increase in $K_oc$ values at a certain higher pH range. The size exclusion effect appears to be effective only for the specific conditions (HS size or pH) that render HS hole st겨ctures to fit a target PAH.

An Overview of the UF/MF Membranes for Water Treatment ; Perparetion Methods and Applications

  • 김정학
    • Proceedings of the Membrane Society of Korea Conference
    • /
    • 1997.04a
    • /
    • pp.1-54
    • /
    • 1997
  • MF : 0.01~submicron범위의 Pore를 가지는 막으로서 주로 입자제거 및 제균목적으로 사용 UF : MWCO 수천~백만(0.001~0.01$\mu$m)의 분리능력을 가지는 막으로서의 고분자 콜로이드에서 미립자, 균등에 이르기까지 물질을 분리, 농축, 정제하는데 사용

  • PDF

Fe/Mn Removal and Membrane Fouling in Combined Chlorination/UF Systems for Drinking Water Treatment (혼성 막여과 공정을 이용한 철/망간의 제거 및 막오염 평가)

  • 추광호;이해범;최상준
    • Proceedings of the Membrane Society of Korea Conference
    • /
    • 2004.07a
    • /
    • pp.115-131
    • /
    • 2004
  • .Oxidized Mn and Fe retained by UF did not cause membrane fouling, but reduced it. .Periodic backwashing rather aggravated fouling due to the deposition of Mn oxides on the outside, which was associated with oxidation kinetics.

  • PDF

The Commercial Use of Ultrafiltration Membranes in the Resolution of Aqueous Problems

  • Layton, R.B.
    • Proceedings of the Membrane Society of Korea Conference
    • /
    • 1997.06a
    • /
    • pp.175-181
    • /
    • 1997
  • This paper describes the commercial application of custom ultrafiltration (UF) membranes in the resolution of two aqueous-based problems: the recovery and recycling of laundry wash water and the fmal polishing of sodium hydroxide sterilization solution in the dairy and brewing industries. Both applications are currently in the pilot Stage and employ custom-made UF membranes developed by Liumar Technologies Corporation of Ottawa, Canada.

  • PDF