• Title/Summary/Keyword: Waste-medium

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Development of Substrates for the Production of Basidiocarps of Flammulina velutipes (팽나무버섯 자실체 생산을 위한 기질개발)

  • Song, Chi-Hyeun;Lee, Chang-Ho;Huh, Tae-Lin;Ahn, Jang-Hyuk;Yang, Han-Chul
    • The Korean Journal of Mycology
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    • v.21 no.3
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    • pp.212-216
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    • 1993
  • Agricultural and forest wastes were tested as substrate for the production of Flammulina velutipes. Among the meranti, pine tree, mixed sawdust, coffee waste and peanut hull tested, coffee waste was the best basal substrate for the production of basidiocarps. When various supplements, such as ricebran, brewer's grain, defatted corn flour, defatted soybean flour and defatted rapeseed flour were tested, defatted corn flour was chosen for the production of basidiocarps. Maximum yield of basidiocarps(129.38 g/bottle) was obtained from the mixed medium at 4 : 1 ratio of coffee waste and defatted corn flour.

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Selection of Working fluid for the Organic Rankine Cycle to Utilize Low-Temperature Waste Heat (저온 폐열을 이용하기 위한 유기랭킨 사이클의 작동유체 선정에 관한 연구)

  • Cho, Soo-Yong;Cho, Chong-Hyun
    • New & Renewable Energy
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    • v.10 no.4
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    • pp.36-46
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    • 2014
  • Low-grade heats are wasted even though an amount of their energy is huge. In the small and medium industrial complex sites, large amount of low-grade thermal energy generated during the manufacturing process is wasted if it is not used directly for building heating or air-conditioning. In order to utilize this waste thermal energy more efficiently, organic Rankine cycle (ORC) was adopted. The range of operating temperature of ORC was set to $60^{\circ}C$ from $30^{\circ}C$ applicable low-temperature waste heat. A study was conducted to select an appropriate organic working fluid based on these operating conditions. More than 60 working fluids were screened. Eleven working fluids were selected based on the requirements as working fluid for ORC such as environmentally friendly, safety, and good operation on the expander. Finally, six working fluids were selected by considering the operating temperature ranges. Then, a cycle analysis was conducted with these six working fluids. As a results, R-245fa and R-134a appeared as appropriate working fluids for ORC operating at low-temperature condition based on the system efficiency and the turbine output power.

Composting Potentials of Food Waste in Seoul and Its Utilization (서울시 음식물쓰레기의 퇴비화 이용 방안)

  • Chung, Jae-Chun;Yoo, Kee-Young;Yoon, Ha-Yeon;Huh, Seok
    • Journal of Animal Environmental Science
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    • v.1 no.1
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    • pp.83-102
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    • 1995
  • Composting is an ecologically sound method of recycling organic waste. Its advantages include the maintenance of soil fertility and improvement of soil physicochemical property. It is an essential part of the waste minimization. That is, composting should be included to increase the recycling rate up to more than 20%. To encourage composting of waste, it is necessary to develop some effective composters of small scale facilities and densely populated areas. For medium and large-size facilities, the optimum process should be selected. Technical counselling and support is desirable for small scale composters for urban residential and rural area. On the other hand, adequate amendment of relevant legislation should be followed to encourage composting. An example of unreasonable legislation is the current fertilizer management act. According to the regulation, the maximum allowable limit of lead in the compost is less than 150ppm, which is too strict. This limit should be increased to at least 300ppm, which is the observed level in most states in USA. At the same time, sound infrastructure should be established and decent publicity work should be achieved to accelerate composting activity. In this paper the desirable standard for some heavy metal concentration in the compost were suggested.

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Understanding and Their Application of GoldSim Transport Pathways to Mass Trasport Simulation (질량 이동 모사 프로그램 개발을 위한 골드심 이동 패쓰웨이의 이해와 활용)

  • Lee, Youn-Myoung;Jeong, Jongtae
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.12 no.2
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    • pp.135-151
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    • 2014
  • It is very important to properly understand such "Transport Pathways" elements as "Pipe" and "Cell" pathways in commercial GoldSim Transport Module (GTM) for developing higer quality models and programs for performance assessment of complex radioactive waste repositories. With an illustrative case under an earthquake scenario, by which an increasement in the groundwater flow rate occurs though the geological medium, ways of avoiding possible modeling errors in the nuclide transport modeling in the radioactive waste repository system for its safety assessment by utilizing such pathways are discussed and a proper usage of the pathways is proposed.

Mcl-PHAs Produced by Pseudomonas sp. Gl01 Using Fed-Batch Cultivation with Waste Rapeseed Oil as Carbon Source

  • Mozejko, Justyna;Wilke, Andreas;Przybylek, Grzegorz;Ciesielski, Slawomir
    • Journal of Microbiology and Biotechnology
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    • v.22 no.3
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    • pp.371-377
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    • 2012
  • The present study describes medium-chain-length polyhydroxyalkanoates (mcl-PHAs) production by the Pseudomonas Gl01 strain isolated from mixed microbial communities utilized for PHAs synthesis. A two-step fed-batch fermentation was conducted with glucose and waste rapeseed oil as the main carbon source for obtaining cell growth and mcl-PHAs accumulation, respectively. The results show that the Pseudomonas Gl01 strain is capable of growing and accumulating mcl-PHAs using a waste oily carbon source. The biomass value reached 3.0 g/l of CDW with 20% of PHAs content within 48 h of cultivation. The polymer was purified from lyophilized cells and analyzed by gas chromatography (GC). The results revealed that the monomeric composition of the obtained polyesters depended on the available substrate. When glucose was used in the growth phase, 3-hydroxyundecanoate and 3-hydroxydodecanoate were found in the polymer composition, whereas in the PHAs-accumulating stage, the Pseudomonas Gl01 strain synthesized mcl-PHAs consisting mainly of 3-hydroxyoctanoate and 3-hydroxydecanoate. The transcriptional analysis using reverse-transcription real-time PCR reaction revealed that the phaC1 gene could be transcribed simultaneously to the phaZ gene.

Statistical Optimization of Chitinase Production by Pantoea dispersa to Enhance Degradation of Crustacean Chitin Waste

  • GOHEL;VIPUL;DERICK JIWAN;PRANAV VYAS;H. S. CHHATPAR
    • Journal of Microbiology and Biotechnology
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    • v.15 no.1
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    • pp.197-201
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    • 2005
  • A novel chitinase-producing bacterial strain of Pantoea dispersa was isolated from the sea near Bhavnagar, India for efficient disposal of chitinous waste from the seafood processing industry. The medium components were optimized by using a cubic model in the central composite design for increasing chitinase production. The optimal concentrations for higher production of chitinase were (g l-1) chitin, 10.0; urea, 0.35; MgSO4 7H2O, 0.08, and CaCl2, 0.15. Here, peptone (0.05 g l-1) was used as a constant variant in all trials. Using a statistical optimization method, the chitinase production was found to increase from 108 to 486.4 units ml-1. Chitin was prepared from the crustacean waste, and Fourier Transform Infrared (FTIR) Spectroscopy was used to characterize the isolated chitin. Chitinous waste degradation was studied in terms of chitinase production.

Behavior of Radioactive Metal Surrogates Under Various Waste Combustion Conditions

  • Yang, Hee-Chul;Lee, Jae-Hee;Kim, Jung-Guk;Yoo, Jae-Hyung;Kim, Joo-Hyung
    • Nuclear Engineering and Technology
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    • v.34 no.1
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    • pp.80-89
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    • 2002
  • A laboratory investigation of the behavior of radioactive metals under the various waste combustion atmospheres was conducted to predict the parameters that influence their partitioning behavior during waste incineration. Neodymium, samarium, cerium, gadolinium, cesium and cobalt were used as non-radioactive surrogate metals that are representative of uranium, plutonium, americium, curium, radioactive cesium, and radioactive cobalt, respectively. Except for cesium, all of the investigated surrogate metal compounds converted into each of their stable oxides at medium temperatures from 400 to 90$0^{\circ}C$, under oxygen- deficient and oxygen-sufficient atmospheres (0.001-atm and 0.21-atm $O_2$). At high temperatures above 1,40$0^{\circ}C$, cerium, neodymium and samarium in the form of their oxides started to vaporize but the vaporization rates were very slow up to 150$0^{\circ}C$ . Inorganic chlorine (NaCl) as well as organic chlorine (PVC) did not impact the volatility of investigated Nd$_2$O$_3$, CoO and Cs$_2$O. The results of laboratory investigations suggested that the combustion chamber operating parameters affecting the entrainment of particulate and filtration equipment operating parameters affecting particle collection efficiency be the governing parameters of alpha radionuclides partitioning during waste incineration.

Determination of major and minor elements in low and medium level radioactive wastes using closed-vessel microwave acid digestion (밀폐형 극초단파 산분해법을 이용한 중${\cdot}$저준위 방사성폐기물의 성분 원소 분석)

  • Lee Jeong-Jin;Pyo Hyung-Yeal;Jeon Jong-Seon;Lee Chang-Heon;Jee Kwang-Yong;Ji Pyung-Kook
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.2 no.4
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    • pp.231-238
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    • 2004
  • The conditions are obtained for the decomposition of solid radioactive wastes, including ion exchange resin, zeolite, charcoal, and sludge from nuclear power plant. In the process of decomposing the radioactive wastes was used the microwave acid digestion method with mixed acid. The solution after acid digestion by the following method was colorless and transparent. Each solution was analyzed with ICP-AES and AAS and the recovery yield for 5 different elements added into the simulated radioactive wastes were over $94{\%}$. The elemental analysis of destructive low and medium level radioactive wastes by the proposed microwave acid digestion conditions concerning the chemical characteristics of each radioactive waste are expected to be useful basic data for development of optimal glass formulation.

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Logical Analysis for Parameters of Radioactive waste Policy using System Dynamics Technique (시스템 다이내믹스 모델링을 통한 중.저준위방사성폐기물시설 부지선정 영향 인자 분석)

  • Lee, Y.J.;Cho, S.K.
    • Journal of Energy Engineering
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    • v.17 no.2
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    • pp.77-87
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    • 2008
  • Decision-making of the site for the medium and low-level radioactive-waste disposal facilities in 2005 can be estimated as a success. But the limits exposed during the process still remain as problems to be solved. Analyzing the causes of success and failure of the policy and their correlation was expected to provide an effective guideline on future policies. The analysis shows that the transparency of policy makers, the level of community supports and the public relations are decisive factors. System dynamics, a synthetic analyzing tool, is used as a methodology for policy analysis. The result of the system dynamics analysis shows that public confidence is to be the key role to for and against logics when transparency of stakeholder, subsidy and public information are set as adjustable parameters. Public confidence takes a role of leverage that can convert tendency of conclusion by the opinion which influenced by selected parameters.

Effects of Cultivation Condition on Growth of the Hydrogen Sulfide-Degradating Thiobacillus sp. IW. Isolated from Waste Coal Mine Water (폐탄광수에서 분리한 황화수소 분해 세균 Thiobacillus sp. IW.의 성장조건)

  • 차진명;박열이인화
    • KSBB Journal
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    • v.9 no.3
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    • pp.287-293
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    • 1994
  • A bacterium isolated from waste coal mine water around Hawsun had an ability for the degradation of hydrogen sulfide. The isolate was identified as Thiobacillus sp. IW. on the basis of its morphological, physiological and chemotaxonomical characteristics. The optimum pH and temperature were 7 and $30^{\circ}C$, respectively. Growth occurred in a pH range of 3 to 9. Due to the sulfate accumulated in liquid medium, the pH decreased. As a consequence the cell growth was inhibited. Potasium nitrate and glutamic acid were utilized as a nitrogen source but urea and ammonium chloride not consumed. Denitrification occurred in a basal medium containing the glucose but did not in a basal medium containing the malate. The maximum specific growth rate of cell was 0.78h-1 and generation time was 0.9 hour. The cell productivity was 6.25mg/1$.$h and the isolate grew logarithmically up to 18 hour. These results indicate that the isolate can be a suitable bacterium responsible for degradation of hydrogen sulfide as malodorous compounds.

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