• Title/Summary/Keyword: pyrolysis process

Search Result 439, Processing Time 0.029 seconds

Process Design and Simulation of Fast Pyrolysis of Brown Seaweed (갈조류 급속열분해 공정의 모사와 설계)

  • Brigljevic, Boris;Woo, Hee Chul;Liu, Jay
    • Clean Technology
    • /
    • v.23 no.4
    • /
    • pp.435-440
    • /
    • 2017
  • Fast pyrolysis of third generation biomass, including micro- and macroalgae for biofuel production has recently been studied and compared experimentally to first- and second-generation biomass. Compared to microalgae, however, process design and simulation study of macroalgae for scale-up has been rare in literature. In this study, we designed and simulated an industrial scale process for producing diesel range biofuel from brown algae based on bench scale experimental data of fast pyrolysis using a commercial process simulator. During process design, special attention was paid to the process design to accommodate the differences in composition of brown algae compared to terrestrial biomass. The entire process of converting 380,000 tonnes of dry brown algae per year into diesel range biofuel was economically evaluated and the minimum (diesel) selling price was also estimated through techno-economic analysis.

Epitaxial Growth of Pb(Zr, Ti)$O_3$Thin Films on $LaAlO_3$ Substrates by Dipping-Pyrolysis Process

  • Hwang, Kyu-Seog;Kim, Byung-Hoon
    • The Korean Journal of Ceramics
    • /
    • v.3 no.4
    • /
    • pp.253-256
    • /
    • 1997
  • Epitaxially grown Pb(Zr, Ti)O$_3$thin films were prepared on LaAlO$_3$substrates by the dipping pyrolysis process using metal naphthenates as starting materials Homogeneous Pb-Zr-Ti solutions with toluene were spin-coated onto the substrates and pyrolyzed at 50$0^{\circ}C$ Highly oriented Pb(Zr, Ti)O$_3$films confirmed by X-ray diffraction $\theta$-2$\theta$ scans were obtained by heat-treated at 75$0^{\circ}C$ in air The X-ray pole-figure analysis and reciprocal-space mapping of the resulting 0.6$\mu\textrm{m}$ films showed that the thin films comprising the c-axis oriented tetragonal phase have an epitaxial relationship with the LaAlO$_3$substrates.

  • PDF

Zn$_2SiO_4$ : Mn Phosphor Particles Prepared by Spray Pyrolysis Process

  • Kang, Yun-Chan;Park, Hee-Dong;Lim, Mi-Ae
    • Journal of Information Display
    • /
    • v.2 no.4
    • /
    • pp.57-62
    • /
    • 2001
  • Green-emitting $Zn_2SiO_4$:Mn phosphor particles having a spherical shape and high luminescence intensities under VUV were prepared by spray pyrolysis process under severe preparation conditions. The type of precursor solutions affected the morphology and luminescence characteristics of the prepared particles. The particles prepared from the clear solution by laboratory-scale process had spherical shape and dense morphology, while the particles prepared from the severe preparation conditions had rough surface and collapsed structure. However, the particles prepared from the colloidal solution utilizing fumed silica were spherical in shape and filled morphology at the severe preparation conditions of high flow rate of carrier gas, high concentration of solution, and large reactor size. The prepared $Zn_2SiO_4$:Mn phosphor particles with complete spherical shape had higher photoluminescence intensity than that of the commercial product prepared by solid state reaction.

  • PDF

Hydrogen Storage by Carbon Fibers Synthesized by Pyrolysis of Cotton Fibers

  • Sharon, Maheshwar;Sharon, Madhuri;Kalita, Golap;Mukherjee, Bholanath
    • Carbon letters
    • /
    • v.12 no.1
    • /
    • pp.39-43
    • /
    • 2011
  • Synthesis of carbon fibers from cotton fiber by pyrolysis process has been described. Synthesis parameters are optimized using Taguchi optimization technique. Synthesized carbon fibers are used for studying hydrogen adsorption capacity using Seivert's apparatus. Transmission electron microscopy analysis and X-ray diffraction of carbon fiber from cotton suggested it to be very transparent type material possessing graphitic nature. Carbon synthesized from cotton fibers under the conditions predicted by Taguchi optimization methodology (no treatment of cotton fiber prior to pyrolysis, temperature of pyrolysis $800^{\circ}C$, Argon as carrier gas and paralyzing time for 2 h) exhibited 7.32 wt% hydrogen adsorption capacity.

Numerical Simulations of the Pyrolysis of 1, 2 Dichloroethane

  • Lee, Ki-Yong
    • Journal of Mechanical Science and Technology
    • /
    • v.16 no.1
    • /
    • pp.102-108
    • /
    • 2002
  • Numerical simulations of 1, 2 dichloroethane(EDC) pyrolyisis are conducted to understand the process in the production of the vinyl chloride monomer (VCM) and by-products. A chemical kinetic mechanism Is developed, with the adopted scheme involving 44 gas-phase species and 260 elementary forward and backward reactions. Detailed sensitivity analyses and the rates of production analysis are performed on each of the reactions and the various species, respectively. The concentrations of EDC, VCM, and HCI predicted by this mechanism are in good agreement with those deduced from experiments of commercial and laboratory scale. The mechanism is found to accurately predict the EDC yield an(1 the production of by-products by varying the ranges of pyrolysis temperature, residence time, and pressure which impact on the pyrolysis of 1, 2 dichloroethane. The influence of reactions related to H atom on the relative sensitivity of EDC becomes important as the residence time increases. The pyrolysis of EDC mainly occurs through C$_2$H$_4$Cl$_2$+Cl=CH$_2$CICHI+HCI.

Operating Characteristics of Pilot Scale Multi-Staged Waste Pyrolysis & Gasification System (파일럿 규모의 폐기물 다단열분해 가스화시스템의 운전특성)

  • Lee, Jeong-Woo;Yu, Tae-U;Bang, Byeong-Ryeol;Moon, Ji-Hong;Lee, Jae-Uk;Park, Sang-Shin;Kim, Nack-Joo
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2009.11a
    • /
    • pp.331-335
    • /
    • 2009
  • A novel multi-staged waste pyrolysis & gasification system of pilot scale (~1 ton/day) is designed and constructed in Korea Institute of Industrial Technology. The pyrolysis & gasification system is composed of pyrolysis & gasification system, syngas reformer, syngas cleaning system, gas engine power generation system and co-combustion system. For each unit process, experimental approaches have been conducted to find optimal design and operating conditions. As a result, We can produce syngas with a calorific value of ~4000 kcal/$Nm^3$ and cold gas efficiency of the system is more than 55 % in case of waste plastic and oxygen as a gasifying agent.

  • PDF

Spray pyrolysis synthesis of mesoporous TiO2 microspheres and their post modification for improved photocatalytic activity

  • Choi, Jaehyung;Yoo, Kye Sang;Kim, Jinsoo
    • Korean Journal of Chemical Engineering
    • /
    • v.35 no.12
    • /
    • pp.2480-2486
    • /
    • 2018
  • Mesoporous $TiO_2$ microspheres were prepared by spray pyrolysis for photocatalysis. Post modification of $TiO_2$ by heat treatment was performed to optimize its photocatalytic performance. First, spherical $TiO_2$ particles with mesoporous structure were synthesized at pyrolysis temperatures of 500, 600, and $700^{\circ}C$. After characterization by XRD, SEM, and $N_2$ adsorption, a sample prepared at $500^{\circ}C$ was found to possess desirable properties for photocatalytic performance through post-modification. In methylene blue degradation, mesoporous $TiO_2$ microspheres synthesized at $500^{\circ}C$ outperformed other microspheres. Furthermore, samples obtained by spray pyrolysis at $500^{\circ}C$ were calcined at various temperatures as a post-modification process. The sample calcined at $350^{\circ}C$ showed improved photocatalytic activity due to optimal anatase crystallinity and surface area.

Process Development of Pyrolysis Liquefaction for Waste Plastics (폐플라스틱의 열분해 유화기술 개발)

  • Nho Nam-Sun;Shin Dae-Hyun;Park Sou-Won;Lee Kyong-Hwan;Kim Kwang-Ho;Jeon Sang-Goo;Cho Bong-Gyu
    • New & Renewable Energy
    • /
    • v.2 no.2 s.6
    • /
    • pp.118-125
    • /
    • 2006
  • The target of this work was the process development of demonstration plant to produce the high quality alternative fuel oil by the pyrolysis of mixed plastic waste. In the first step of research, the bench-scale units of 70 t/y and the pilot plant of 360 t/y had been developed. Main research contents in this step were the process performance test of pilot plant of 360 ton/year and the development of demonstration plant of 3,000 t/y, which was constructed at Korea R & D Company in Kimjae City. The process performance of pilot plant of 360 t/y showed about 80% yield of liquid product, which was obtained by both light gas oil(LGO) and heavy gas oil(HGO), The boiling point range distribution of LO product that was mainly consisting of olefin components in PONA group appeared at between that of commercial gasoline and kerosene. On the other hand, HO product was mainly paraffin and olefin components and also appeared at upper temperature distribution range than commercial diesel. Gas product showed a high fraction of $C_3\;and\;C_4$ product like LPG composition, but also a high fraction of $CO_2$ and CO by probably a little leak of process.

  • PDF

Process Development of Pyrolysis Liquefaction for Waste Plastics (폐플라스틱의 열분해 유화기술 개발)

  • Nho, Nam-Sun;Shin, Dae-Hyun;Park, Sou-Won;Lee, Kyong-Hwan;Kim, Kwang-Ho;Jeon, Sang-Goo;Cho, Bong-Gyu
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2006.06a
    • /
    • pp.523-526
    • /
    • 2006
  • The target of this work was the process development of demonstration plant to produce the high quailty alternative fuel oil by the pyrolysis of mixed plastic waste. In the first step of research, the bench-scale units of 70t/y and the pi lot plant of 360 t/v had been developed. Main research contents in this step were the process performance test of pilot plant ot 360ton/year and the development of demonstration plant of 3 000 t/y which was constructed at Korea R & D Company in Kimjae City. The process performance of pilot plant of 360 t/v showed components in PONA group appeared at between that of commercial gasoline and kerosene. On the other hand, HO product was mainly paraffin and olefin components and also appeared at upper temperature distribution range than commercial diesel. Gas product showed a high fraction of $C_3\;and\;C_4$ product like LPG composition, but also a high fraction of $CO_2$ and CO by probably a little leak of process.

  • PDF

Synthesis of Tetrafluoroethylene from the Pyrolysis of Chlorodifluoromethane in the Presence of Steam (과열 수증기를 이용한 클로로디플루오르메탄 열분해 반응에 의한 테트라플루오르에틸렌의 합성)

  • Han, Myungwan;Kim, Beom-Sik;Kim, Chul-Ung;Lee, Jung-Min
    • Applied Chemistry for Engineering
    • /
    • v.10 no.2
    • /
    • pp.190-195
    • /
    • 1999
  • The thermal pyrolysis of chlorodifluoromethane (R22) for producting tetrafluoroethylene (TFE) has been studied using the tubular reactor designed by the authors. The reaction temperature over $600{\sim}850^{\circ}C$, residence time over 0.005~0.6 sec, and steam/R22 ratio 3 to 30 were varied through experiments to analyze the effect of these variables on the conversion of R22 and selectivity for TFE. We have provided the guidelines for the optimal operation and design for the pyrolysis reactor. With increasing the dilution ratio, not only the conversion of R22 but also the selectivity for TFE increase. The optimum range of reaction temperature was $700{\sim}750^{\circ}C$ and the residence time 0.07~0.1 sec. In the kinetic study, first order rate equation was fitted well with the experimental data. This indicates that the main reaction step is a $CF_2$ generation from R22 pyrolysis. The range of activation energy for the rate constant was obtained 44.7~48 kcal/mol.

  • PDF