2015 Annual Meeting of The Institute of Electrostatics JapanTokyo Metropolitan University
September 24-25, 201525aC-1
September 25th (Fri.), <10:00-12:00>
Room 3

Effect of ozone applying method on removing floating weeds〇Yoshihiro KAWADA*, Keiko OSHIDA** and Hirotaka SHIMIZU**The Polytechnic University of Japan **Nihon University

Abstract:
Colonies of floating weeds are grown over at the stagnant water area ofa lake and a river. These often cause environmental issue. Therefore, it isneeded for maintain water environment to prevent growth for the floating weeds.
The aim of this study is to control growth and death of floating weeds with ozone.
The applying method of ozone to floating weeds is investigated. As results, whenozone is applied to the gas around floating weeds, floating weeds are deadeffectively. To apply the water with ozone to the floating weeds is less effective
than to apply to air around floating weeds. In case that the ozone generator isdriven by solar array, the floating weeds having the leaves of approximately 5times area as large as that of solar array could be dead.

2015 Annual Meeting of The Institute of Electrostatics JapanTokyo Metropolitan University
September 24-25, 2015

25aC-2September 25th (Fri.), <10:00-12:00>
Room 3

Effect of Swirling Liquid Flow on Plasma-based Water
Treatment○Shohei MATSUNARI, Shinichi AKAGAWA, Shuichi AKAMINE, Ryuta ICHIKI,
Seiji KANAZAWA
Department of Electrical and Electronic Engineering, Oita University

Abstract:
Three-dimensional (3D) printing technology is now essential in making
things, and we have introduced this technology into the design and fabrication ofnon-thermal plasma reactors. In this study, water injection part of the plasma
reactor was prepared by a 3D printer. To produce swirling liquid flow in therunning water along an inner wall of a cylindrical tube, a specific design wasadded into the injector. Three types of the injectors were prepared by the 3D
printer and those performances were evaluated by the comparison of thedecolorization rate of indigo carmine solution. As a result, the swirling liquid jettype injection was most effective method under our experiments for water
treatment.

2015 Annual Meeting of The Institute of Electrostatics JapanTokyo Metropolitan University
September 24-25, 201525aC-3
September 25th (Fri.), <10:00-12:00>
Room 3

Influence of Pulse Width on Decomposition ofDichloromethane by Discharge Inside Bubbles in Water○Masashi IWABUCHI*，Keita WADA*，Katsuyuki
TAKAHASHI*，Koichi TAKAKI*，Naoya SATTA***Faculty of Engineering, Iwate University,**Faculty of Agriculture, Iwate
University

Abstract:
Influence of pulse width on decomposition of dichloromethane bydischarge inside bubbles in water has been investigated. The discharge reactor
consists of a glass tube and a tungsten wire inserted into the glass tube, which isimmersed in the water. Argon gas is injected into the glass tube to generate
bubbles in the water.
Two types of pulsed generator, a magnetic pulse compression circuit
and an inductive-energy storage system using semiconductor opening switch,
are used to generate high voltage pulse with various pulse widths.
Dichloromethane (DCM) which is a volatile organic compound isemployed as a specimen to evaluate decomposition efficiency. The DCM isdecomposed successfully by discharge inside bubbles in water. TOC removal
efficiency and DCM decomposition efficiency are similar in each pulse width.
Energy efficiency for decomposition increases by decreasing the pulse width.

2015 Annual Meeting of The Institute of Electrostatics JapanTokyo Metropolitan University
September 24-25, 201525aC-4
September 25th (Fri.), <10:00-12:00>
Room 3Development and evaluation of pencil type solution plasma
reactor〇1K. Koyama, 123O. L. Li., 1234 N. Saito
1Graduate School of Engineering, Nagoya Univ. , 2Green Mobility Collaborative
Research Center, Nagoya Univ., 3Institute of Innovation for Future Society, 4
JST-CREST

Abstract:
Solution plasma (SP) is defined as; one type non-equilibrium, cold
plasma in liquid. SP is different from other systems by avoiding inert gas usage,and generating inside solution environment. SP has been used for metal
nanoparticles
synthesis,
surfacemodifications,organic-compound
decompositions, and carbon materials synthesis. There are application
limitations because of small plasma area inside solution. It is necessary toincrease the plasma area in order to obtain higher efficiency from the process. In
this study, we have developed a new reactor for continuous processing andcontinuous synthesis of the material. Non-equilibrium plasma was generated
with two type of reactors (attached needle electrode and coil electrode or meshelectrode). Despite of two reactor usage, solution temperature didn’t increase
even after 30 min of discharge. It is observed that by decreasing electrodes
distance, plasma is shifting from the end of needle electrode and generating
between mesh and needle electrodes with a higher energy. We have succeeded
in developing a new reactor, which can generate plasma continuously.

2015 Annual Meeting of The Institute of Electrostatics JapanTokyo Metropolitan University
September 24-25, 2015

25aC-5September 25th (Fri.), <10:00-12:00>
Room 3Effect of irradiation distance of plasma jet on ROS supply toliquid bottom.
○Shota KUSUMEGI, Akihiro KUDO, Takuya TSURUMARU, Tomohiro
SAKANOSHITA, Akihiro SATO, Yasutaka WAKABAYASHI, Toshiyuki
KAWASAKI
Nippon Bunri Univ.

Abstract:
The supply of reactive oxygen species (ROS) to a target through liquid
byplasma jet should be clarified. However, the etailed mechanisms are not clear
now. Therefore, the ROS generation in liquid by the plasma jet has been studied
by various measurement methods. In this study, the use of a gel reagent withiodine-starch reactions has been focused as a plasma-generated ROS detection
method. The gel reagent can work even in water. In this paper, a plasma jet wasirradiated onto the water surface, and the ROS reaching the water bottom weredetected using the gel reagent set in the water. The plasma jet generator was
made of a glass tube with wrapped powered and grounded electrodes. Heliumgas with 1% oxygen was supplied into the glass tube at a flow rate of 3 L/min.
The water layer with a thickness of 1 mm was placed onto the gel reagent. Theirradiation distance was varied from 5 to 30 mm. As a result, the ROS supply to
the water bottom by plasma jet was significantly influenced by the irradiation
distance. The results obtained in this study also indicated that the ROS supply
mechanisms were markedly different from the ozone exposure.

2015 Annual Meeting of The Institute of Electrostatics JapanTokyo Metropolitan University
September 24-25, 2015

25aC-6
September 25th (Fri.), <10:00-12:00>
Room 3

Decomposition characteristic of olive oil and various fatty
acids in oil-water mixture by pulsed discharge plasma andozone treatments○Takanori TANINO, Daiki KAWAI and Takayuki OHSHIMA
Graduated School of Science and Technology, Gunma University

Abstract:
Decomposition characteristic of olive oil in oil-water mixture by pulsed
discharge plasma and ozone treatment was investigated. The decomposition
profile of olive oil showed liner decrease for the initial
10 min treatment and became slower after that in the pulsed discharge
plasma treatment. In ozone treatment, rapid decrease was observed for initial 5min treatment. Solid substance was produced by both pulsed electric discharge
and ozone treatment. Decomposition characteristics of several chain length fatty
acids by both treatments were also investigated. As short and middle chain fatty
acids, butyric and caprylic acids were used, respectively. These short and middle
chain fatty acids were successfully decomposed by the pulsed discharge plasma
treatment. On the other hand, ozone treatment could not decompose these fatty
acids.

2015 Annual Meeting of The Institute of Electrostatics JapanTokyo Metropolitan University
September 24-25, 201525aC-7
September 25th (Fri.), <10:00-12:00>
Room 3Effect of Organic Acids on Cesium Removal fromContaminated Soil by the Electrokinetic Remediation〇Tomoaki MIURA*，Mahmudul KABIR*， Masafumi SUZUKI*，Shyunsuke
NAKAJIMA**，Shigehisa MORI***Graduate School of Engineering and Resource Science, Akita University，**Sanwa Tekki Corporation

Abstract:
Radioactive materials were scattered on the vast area near Fukushima,
Japan after the Fukushima Atomic Power Plant accident after the earthquake
occurred on the 11th March, 2011. Among the radioactive materials, especiallyCesium (Cs) caused a severe contamination of soil and due to its longer half-life(30.0 years), the removal of Cesium is urgently needed. However, the removal ofCesium from soil especially in the mountainous area is not so easy. We haveproposed a method of Cesium removal which can also be applied in the slopearea. Non-radioactive Cesium was used in our experiments. During theElectrokinetic process of the contaminated soil, acetic acid and citric acid wereapplied in purpose of more Cesium removal. These acids are easily
decomposable in nature. Without any electric field, a small range of Cesium
removal was possible with tap water, and the two organic acids. Performing theexperiment with Electrokinetic process, using acetic acid as electrolyte, showeda better result considering the amount of removal of Cesium. Thus, ourElectrokinetic process has showed good results to remove Cesium fromcontaminated soil.