• 제목/요약/키워드: production efficiencies

검색결과 321건 처리시간 0.027초

고온 협기성 연속회분식 공정에 의한 도시하수슬러지 소화 (Thermophilic Sewage Sludge Digestion by Anaerobic Sequencing Batch Reactor)

  • 허준무;박종안;이종화;손부순;장봉기
    • 환경위생공학
    • /
    • 제14권3호
    • /
    • pp.130-138
    • /
    • 1999
  • The feasibility of municipal sewage sludge digestion was investigated by using thermophilic anaerobic sequencing batch reactor(ASBR). One-day settle time was enough for the high performance of solid-liquid separation. The conversion of semi-continuous mode to sequencing batch mode is easily achieved without any adverse effects, although the large amount of sludge equal to the volume ratio of 0.3~06 to reactor volume was added in the feed step of the start-up. The ASBRs had higher conversion capability of organics to biogas than the control reactor. Gas yields of the ASBRs were increased by the average of 50% over the control reactor across a range of hydraulic retention time(HRT)s from 10days to 5days. The thermophilic reactors showed higher gas production than mesophilic reactor. Removal efficiencies of organic matter exceeded 80% on the basis of supernatants, except that at the reactor. Solid-liquid separation was essential in the performance of the ASBR, especially, at the lower HFT. The ASBRs were highly efficient in the retention of activated biomass within the reactor. thus compensating for increased equivalent organic loading rate through increased solids retention times followed by the increased solids, while maintaining shorter HRTs.

  • PDF

김치생산용 알타리무 전처리 가공시스템 개발(I) - 무청·뿌리끝부 절단장치 - (Development of the Altari Radish Pre-Processing System for Kimch Production (I) - Leaf and root tail cutting equipment -)

  • 민영봉;김성태;강동현;정태상;나우정
    • Journal of Biosystems Engineering
    • /
    • 제29권5호
    • /
    • pp.451-456
    • /
    • 2004
  • To establish a Altari radish pre-processing system far kimchi, the leaves and root tail of the Altari radish cutting de-vices were developed. The cutting resistances depend on the edge angles, oblique angles and cutting speeds were measured and analyzed. The experiments were performed to reveal the optimal conditions that showed the minimum cutting resistances acting on the materials. As the results, the optimum conditions that acting on the leaves were at edge angle $25^{\circ}$, oblique angle $40^{\circ}$ and cutting speed 0.5 m/s, and those acting on the root tails were at edge angle $20^{\circ}$, oblique angle $30^{\circ}$ and cutting speed 0.5 m/s, respectively. Considered a safety conception, the oblique angle of the leaves cutting device was adjusted as $20^{\circ}$, and then the cutting efficiencies of the both devices at these conditions were showed perfect performances.

호소 퇴적층으로부터 용출되는 인 제거를 위한 황토 복합체 개발 (Development of Loess Composite for the Control of Phosphorus Release from Lake Sediments)

  • 신관우;김금용;이상일
    • 한국물환경학회지
    • /
    • 제28권1호
    • /
    • pp.50-56
    • /
    • 2012
  • In this study, loess composites, loess with lanthanum and with aluminum, were made and evaluated for treatment of phosphorus removal in natural water system. Desiccation method for production of loess composite was superior to centrifugation method in obtaining high concentrated composites of lanthanum and aluminum. Washing of loess lanthanum composite by water did not deteriorat the lanthanum concentration in the composite, but this lowered the aluminum concentration of loess aluminum composite. Total of 15 and 37.5% of aluminum contents were removed after first washing treatment in aluminum loess of 0.05% and 0.1% respectively. However, no more aluminum loss was monitored with increase of washing times. Phosphorus removal efficiencies were not decreased with washed loess aluminum composite. Phosphorus removal was successfully achieved by adsorption of phosphate to loess composite at pH range of 5.0 ~ 8.0. Freundlich and Langmuir adsorption isotherm was observed in the adsorption of phosphate for loess composite. Dosages of 0.05% and 0.1% lanthanum composite for 95% of phosphorus removal could reduce its usage amount to 25% and 50%, respectively, comparing with dosage of loess alone. Dosages of 0.05% and 0.1% aluminum composite could reduce its usage amount to 48% and 63%, respectively.

하수처리공정의 물 자원 생산 시스템 설계에 대한 적용 1. 하수처리공정의 처리효율 분석 및 평가 (Application of Sewage Treatment Processes to a System Design for Water Resource Production 1. Analysis and Assessment of Sewage Treatment Process Efficiency)

  • 신춘환
    • 한국환경과학회지
    • /
    • 제25권8호
    • /
    • pp.1155-1163
    • /
    • 2016
  • The treatment efficiencies of domestic sewage treatment processes were analysed and assessed to suggest and design a suitable technology for coal seam gas (CSG) water treatment. Two sewage treatment plants (S and G in Busan) were selected. The former operates with standard activated sludge and modified Ludzak Ettinger processes while the later uses the combination of $A_2/O$ and gravity fiber filtration. For both plants, the concentrations of BOD, $COD_{Mn}$, T-N and T-P were about 5.0, 19.0, 5.0, 11.0 and 1.0 ppm, respectively, which satisfy the discharge standards. Therefore, although sewage treatment processes seems to be applicable for CSG water treatment, additional processes to remove total dissolved solids and ionic compounds (i.e. bicarbonate) need to be introduced to produce fit-for-purpose water resources for beneficial use (in accordance with Water ACT 2013). This, for the CSG treatment process design, it is necessary to align the operating conditions with merging methods of combinable unit technology obtained from sewage treatment processes.

Experimental Study on the Input Coupled type CVT combined a Differential Gear and V-Belt type CVU

  • Kim, Yeon-Su;Park, Sang-Hoon
    • International Journal of Precision Engineering and Manufacturing
    • /
    • 제2권1호
    • /
    • pp.43-55
    • /
    • 2001
  • A continuously variable transmission(CVT) mechanism composed of one differential gear unit and one continuously variable unit(CVU) can be classified according to the coupling of CVU and the direction of power flows. The mechanism has many advantages which are the decrease of CVT size, the increase of overall efficiency, the extension of speed ratio range and generation of geared neutral. The CVT mechanism considered here is the input coupled type which combines the functions of a 2K-H I type differential gear unit and a V-belt type CVU. One shaft of the CVU is connected directly to the input shaft and another shaft of it is linked to the differential gear unit. It is shown that some fundamental relations(speed ratios, power flows and efficiencies) for twelve mechanisms previously described are valid by various experimental studies, six of them produce a power circulation and the others produce a power split. Some useful comparisons between theoretical analysis and experimental results are presented. General properties also are discussed, which connect following power flow modes : (a) power circulation mode; (b) power split mode.

  • PDF

The Study on Estimation of Assembly Efficiency via Diversifying Joinery Techniques for Wooden Furniture - Focused on the Studio Classes of Furniture Design Department of Two Universities in Korea -

  • Choi, Ki
    • 한국가구학회지
    • /
    • 제20권3호
    • /
    • pp.239-246
    • /
    • 2009
  • The joinery technique, as one of manufacturing techniques for the wooden furniture, influences the production process, the economic efficiency, and the diversification of design. Especially, the usage of machine tools can determine how much the students can enhance their design expression capabilities during the practice class in furniture design courses of domestic universities, in accordance with whether to utilize the machine tools or not, and how much and frequent to use the machine tools. The study proved that the joinery techniques, based on the high-tech machine, has more efficiencies in the various aspects, including the easiness to manufacture the products, and the diversity of design than the joinery technique, based on the handcraft-only. As the ground of this, this study estimated the time to produce the wooden furniture by machine tools and by handcraft-only, each. Also, this study show the comparison of the features of three different joinery techniques. On the basis of this comparison, this study made the conclusion that the machine-based joinery technique, which is used in the practice class, is the best method to bring the best results in manufacturing the wooden furniture.

  • PDF

Incorporation of Nasutitermes takasagoensis Endoglucanase into Cell Surface-Displayed Minicellulosomes in Pichia pastoris X33

  • Ou, Jingshen;Cao, Yicheng
    • Journal of Microbiology and Biotechnology
    • /
    • 제24권9호
    • /
    • pp.1178-1188
    • /
    • 2014
  • In this study, the yeast Pichia pastoris was genetically modified to assemble minicellulosomes on its cell surface by the heterologous expression of a truncated scaffoldin CipA from Clostridium acetobutylicum. Fluorescence microscopy and western blot analysis confirmed that CipA was targeted to the yeast cell surface and that NtEGD, the Nasutitermes takasagoensis endoglucanase that was fused with dockerin, interacted with CipA on the yeast cell surface, suggesting that the cohesin and dockerin domains and cellulose-binding module of C. acetobutylicum were functional in the yeasts. The enzymatic activities of the cellulases in the minicellulosomes that were displayed on the yeast cell surfaces increased dramatically following interaction with the cohesin-dockerin domains. Additionally, the hydrolysis efficiencies of NtEGD for carboxymethyl cellulose, microcrystal cellulose, and filter paper increased up to 1.4-fold, 2.0-fold, and 3.2-fold, respectively. To the best of our knowledge, this is the first report describing the expression of C. acetobutylicum minicellulosomes in yeast and the incorporation of animal cellulases into cellulosomes. This strategy of heterologous cellulase incorporation lends novel insight into the process of cellulosome assembly. Potentially, the surface display of cellulosomes, such as that reported in this study, may be utilized in the engineering of S. cerevisiae for ethanol production from cellulose and additional future applications.

Mapping of Quantitative Trait Loci Affecting Growth Traits in a Japanese Native Chicken Cross

  • Rikimaru, K.;Sasaki, O.;Koizumi, N.;Komatsu, M.;Suzuki, K.;Takahashi, Hideaki
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제24권10호
    • /
    • pp.1329-1334
    • /
    • 2011
  • The Hinai-dori is a breed of chicken native to Akita Prefecture, Japan. An $F_2$ resource population produced by crossing low- and high-growth lines of the Hinai-dori breed was analyzed to detect quantitative trait loci (QTL) for growth traits. Highly significant QTLs for body weight at 10 and 14 weeks of age and average daily gain between 4 and 10 weeks and between 10 and 14 weeks of age were accordingly mapped in a common region between ADL0198 and ABR0287 on chromosome 1 and between MCW0240 and ABR0622 on chromosome 4, respectively. A significant QTL for body weight at 4 weeks of age and a significant QTL for average daily gain between 0 and 4 weeks of age were mapped for the first time to the same region flanking ABR0204 and ABR0284 on chromosome 1. These QTLs are good candidates for application in the development of marker-assisted selection strategies for increasing growth efficiencies in the Hinai-dori breed and native breeds of chickens in Asia.

페로브스카이트의 표면 및 계면 결함 제어를 통한 안정성 향상 기술 경향 (Recent Progress in Surface/Interface Defect Engineering of Perovskite for Improving Stability)

  • 김민
    • 접착 및 계면
    • /
    • 제21권2호
    • /
    • pp.41-50
    • /
    • 2020
  • 유무기 할로겐화 납 페로브스카이트 태양전지는 25%을 넘는 높은 효율에도 불구하고 낮은 구동 안정성으로 인해 상용화에 불리하며, 이에 페로브스카이트 재료 내구성 향상을 위한 전략이 필요하다. 페로브스카이트 내구성을 높이기 위해서는 페로브스카이트 재료의 결함 특성과 열화 메커니즘 원리에 대해 이해해야 하며, 결함 제어를 통한 소자 안정화 전략을 취해야 한다. 이 총설에서는 페로브스카이트 내 결함 형성 및 소자 구동에 연관된 광물리 특징과 물질 열화 현상을 소개하고, 이를 해결하기 위한 다양한 결함 제어 기술 동향을 정리하였다.

Influence of Arbuscular Mycorrhizal Fungus and Kinetin on the Response of Mungbean Plants to Irrigation by Seawater

  • Rabie, G.H.
    • Mycobiology
    • /
    • 제32권2호
    • /
    • pp.79-87
    • /
    • 2004
  • An experiment was carried out to investigate the effects of pre-inoculation with the mycorrhizal fungus Glomus clarum and foliar application of kinetin on the growth of mungbean plant irrigated wht different dilution of seawater. Arbuscular-mycorrhizal(AM) infection significantly increased dry weight, height, chlorophyll, sugar and protein content, nitrogen and phosphorus-use efficiencies, leaf conductivity, transpiration rate, nitrogenase, acid and alkaline phosphates activities of all salinized mungbean plants in comparison with control and non-mycorrhizal plants irrespective of the presence or absence of kinetin. Mycorrrhizal plants showed higher concentrations of N, P, K, Ca and Mg and lower Na/N, Na/P, Na/K, Na/Ca and Na/Mg ratios than non-mycorrhizal plants when irrigated with certain dilution of seawater. Mungbean plants showed 597% and 770% dependency on AM fungus G. clarum in absence and presence of kinetin, respectively, for biomass production under a level of 30% of seawater. The average value of tolerance index for mycorrhizal plants accounted 267% and 364% in absence and presence kinetin respectively. This study provides evidence for the benefits of kinetin which are actually known for mycorrhizal than non-mycorrhzal plants. AM fungus and kinetin protected the host plants against the detrimental effects of salt. However, mycorrhizal infection was much more effective than kinetin applications. Thus management applications of this arbuscular mycorrhizal endophyte(G. clarum) with kinetin could be of importance in using seawater in certain dilution for irrigation in agriculture.