SEKITO Tomoo

写真a

Title

Associate Professor

Research Fields, Keywords

Environmental Engineering

Mail Address

E-mail address

Laboratory Phone number

+81-985-58-7335

Laboratory Fax number

+81-985-58-7344

Graduating School 【 display / non-display

  •  
    -
    1994.03

    Hokkaido University   Faculty of Engineering   Department of Sanitary Engineering   Graduated

Graduate School 【 display / non-display

  •  
    -
    1996.03

    Hokkaido University  Graduate School, Division of Engineering  Division of Sanitary Engineering  Master's Course  Completed

Degree 【 display / non-display

  • Hokkaido University -  Doctor (Engineering)

 

Papers 【 display / non-display

  • Estimating the flow of recyclable items and potential revenue at a waste bank: the case in Malang City, Indonesia

    Tomoo Sekito, Tri Budi Prayogo, Christia Meidiana, Hiroshi Shimamoto, Yutaka Dote

    Environment, Development and Sustainability     2018.05  [Refereed]

    Joint Work

    DOI

  • Effect of the Quality of Wastewater from Swine Production on the Simultaneous Recovery of Ammonium, Phosphorus and Potassium and the Composition of the Recovered Product

    Dote Yutaka, Sekito Tomoo

    Journal of the Japan Society of Material Cycles and Waste Management   29   250 - 256   2018  [Refereed]

    Joint Work

     View Summary

    In order to clarify the effect of wastewater recovered from swine production on the simultaneous recovery of ammonia, phosphate and potassium, a recovery experiment was carried out using six kinds of primary treatment water obtained from three hog farms in September and November. The compositions of the recovered materials were also investigated. The remaining concentrations of nitrogen, phosphate, potassium and magnesium could be predicted by previously reported methods. The prediction accuracy ranged from half to double the observed concentrations. Under conditions where the observed remaining concentrations of phosphorus were less than 16 mg/L, nitrogen recovery was over 96 %, but the maximum potassium recovery was 67 %. Net phosphorus recovery was over 40 % indicating that more could be recovered more than required to meet wastewater standards. The average nitrogen, phosphate, potassium and magnesium contents in the recovered materials were 19, 19, 3.4 % and 1.4 %, respectively. For these components, more than 80 % of the content was citric acid-soluble. MgNH<sub>4</sub>PO<sub>4</sub>・H<sub>2</sub>O was identified in recovered materials, but others were not. The phosphorus contained in recovered materials was 39 % as MAP, 6 % as MPP and 55 % as other compounds.

    DOI CiNii

  • Inhibition of Biological Treatment of Swine Wastewater by Swine Manure Compost-based Char

    Dote Yutaka, Sekito Tomoo

    Journal of the Japan Society of Material Cycles and Waste Management   29   184 - 190   2018  [Refereed]

    Joint Work

     View Summary

    To clarify the inhibition effect of swine manure compost-based char on the biological treatment of swine wastewater with NH<SUB>4</SUB>-N removed (NRSWW), NH4-N removal experiments and batch biological treatment experiments were performed. NH<SUB>4</SUB>-N removal and C/N ratios in NRSWW increased with the char addition ratio, reaching 40 % and 1.5 at a char addition ratio of 20 %, respectively. The increase in a C/N ratio was affected by TOC dissolution from the char in addition to NH<SUB>4</SUB>-N removal by the char. NH<SUB>4</SUB>-N removal by the char exhibited no inhibition of TOC removal. Biological nitrification was inhibited by NH<SUB>4</SUB>-N removal by the char when the char addition ratio was over 10 %. Chloride ions might be considered an inhibitor of nitrification. No accumulation of nitrate and nitrite appeared, so denitrification occurred sufficiently.

    DOI CiNii

  • Simultaneous Recovery of Ammonium, Phosphorus and Potassium by Crystallization from Swine Wastewater

    Dote Yutaka, Sekito Tomoo

    Journal of the Japan Society of Material Cycles and Waste Management   28   152 - 159   2017

    Joint Work

     View Summary

    In order to determine the optimum conditions for simultaneously recovering ammonia, phosphate and potassium as magnesium ammonium phosphate (MAP) and magnesium potassium phosphate (MPP) by crystallization from swine wastewater, a recovery experiment was carried out using the primary treatment water of actual swine wastewater. Under all conditions, the recovery efficiency of nitrogen was over 95 %. Recovery efficiencies of 80 % and 99 %, respectively, were reached for potassium and phosphate. Considering the maximum recovery efficiency of potassium and the remaining concentration of phosphate, which must be less than 16 mg/L according to the Japanese government, it was found that the optimum conditions were a pH of 9, P/(N+K) of 1.5, and Mg/P of 1.35 in molar ratio. Under these conditions, the recovery efficiency of potassium and the remaining concentration of phosphate were 45 % and 15 mg/L, respectively. The remaining concentrations of nitrogen, phosphate, potassium and magnesium could be predicted by the solubility products of the MAP, MPP and magnesium phosphate obtained in this study. When the discharge standard for phosphorus is applied, P/(N+K) and Mg/P should be determined so that the predicted remaining phosphorus concentration is less than 8 mg/L, which is half the discharge standard for phosphorus.

    DOI CiNii

  • Effect of pH, temperature and cation on cesium leaching from bottom ash

    Yutaka Dote, Tomoo Sekito, Takayuki Shimaoka

    Proceedings of ICLRS2016     49 - 50   2016.06

    Joint Work

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Presentations 【 display / non-display

  • RECYCLING OF POST-CONSUMER PLASTIC PACKAGING INTO CONSTRUCTION MATERIALS

    RAFENOMANANJARA Tsinjo Nirina, Tomoo SEKITO, Yutaka DOTE

    平成30年度 西部支部研究発表会  2019.03  -  2019.03  土木学会西部支部

  • Challenges and benefits of waste banks in Indonesia

    】Satwika Desantina Muktiningsih, Tomoo SEKITO

    平成30年度 西部支部研究発表会  2019.03  -  2019.03  土木学会西部支部

  • Identification of Factors Influencing the Frequency of Recyclable Waste Separation:The Waste Bank Program

    Teuku Riefky AKBAR, Tomoo SEKITO, Sri MARYATI

    平成30年度 西部支部研究発表会  2019.03  -  2019.03  土木学会西部支部

  • The effect of household coal ash on solid waste degradation in a lab-scale landfill reactor with leachate recirculation: A case study of Ulaanbaatar, Mongolia

    Batkhuyag ENKH UCHRAL, Tomoo SEKITO, Yutaka DOTE, Tuuguu ENKHDUL

    平成29年度 土木学会西部支部研究発表会  2018.03  -  2018.03 

  • HOUSEHOLDS RECYCLING BEHAVIOR TOWARD WASTE BANK PROJECT IN KLATEN, INDONESIA

    Dewi Indraswati, Tomoo SEKITO, Yutaka DOTE, Iwan Pratoyo Kusumantoro

    平成29年度 土木学会西部支部研究発表会  2018.03  -  2018.03 

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