Additive Manufacturing Based Design of Metal Continuous Flow Reactor of Inner Micro Structure for Continuous Mixing and Reaction of Chemical Solvents

양정호(Jeongho Yang),강동석(Dongseok Kang),연시모(Simo Yeon),한지수(Jisu Han),손용(Yong Son),심용식(Patrick Y Shim),강동환(Donghwan Kang),최평호(Pyoungho Choi),박상후(Sanghu Park),하철우(Cheolwoo Ha) Korean Society for Precision Engineering 2021 한국정밀공학회지 Vol.38 No.9

Microchannel-based chemical reactor is widely used to develop chemical products. High-efficiency reactors are required to produce high-quality chemical products. The reaction efficiency is highly related to the mixing ratio. In this paper, an inner structure model in the reactor was designed to improve the mixing ratio. Computational fluid dynamic (CFD) analysis was carried out for two-phase flow in a continuous flow reactor using a commercial software. A case model of the different inner structures was designed to evaluate the mixing rate. Velocity profiles, mixing ratio, and pressure fields of each model were obtained by two-fluid flow analysis using CFD. Based on the analysis results, a reactor model with a high mixing ratio was selected. Powder bed fusion based metal additive manufacturing process was performed to manufacture the 3D microchannel-based chemical reactor. It is expected that the proposed reactor could be applied to a high-efficiency reactor system to produce various chemical materials. For instance, it was possible to perform a chemical reaction based on a toxic material, such as, dimethylformamide solution, using the proposed 3D metal microchannel-based reactor.

A Study on the Design and Experiments of a Coil-Type Continuous Reactor for Viscosity Fluid

김도엽(Do Yeop Kim),강호성(Ho Seong Kang),차민철(Min Cheol Cha),이영우(Young Woo Lee),박용근(Yong Geun Park),이응석(Eung Suk Lee) Korean Society for Precision Engineering 2019 한국정밀공학회지 Vol.36 No.5

Reactors are needed to produce polymeric polymers as materials for OLED (Organic Light Emitting Diode). There are many types of reactors that assist in producing chemical reactions. One type, called a coil type, is a continuous reactor that has many advantages compared to other reactors. It can not only manufacture products continuously, but is cheaper and therefore cost efficient. A continuous coil type reactor was designed and manufactured for this study. A precise flow rate cannot be determined because of the numerous variables. An experimental flow rate is obtained when combining the following information: the valve opening angle, the revolution velocity of the screw and the temperature of the reaction. As a result, the study is considered that people who use this device will refer to this to control flow rate and time for reaction.

Continuous synthesis of silver plates in a continuous stirring tank reactor (CSTR)

Tang, Zengmin,Kim, Woo-Sik,Yu, Taekyung Elsevier 2018 Journal of industrial and engineering chemistry Vol.66 No.-

<P><B>Abstract</B></P> <P>In this report, a continuous stirring tank reactor (CSTR) and batch reactor were used for synthesis of silver (Ag) plates. The influences of agitation speed, molar ratio of AgNO<SUB>3</SUB> to NaCl, and concentration of reagent were investigated. Size analysis demonstrated that the size of Ag plates synthesized by the CSTR was larger than the size of plates synthesized by the batch reactor. The reason might be that low concentration of reagent and continuous supply of monomer in CSTR are more favorable for growth of anisotropic structures. CSTR demonstrates good advantages for mass synthesis of Ag plates of large size.</P> <P><B>Graphical abstract</B></P> <P>Large Ag plates were synthesized by using continuous stirring tank reactor (CSTR) in the ambient temperature with a short mean residence time of 5min, has a great improve surface enhanced Raman signal of methylene blue.</P> <P>[DISPLAY OMISSION]</P>

Nitrogen removal, nitrous oxide emission and microbial community in sequencing batch and continuous-flow intermittent aeration processes

Yuepeng Sun,Liwei Xin,Guangxue Wu,Yuntao Guan 대한환경공학회 2019 Environmental Engineering Research Vol.24 No.1

Nitrogen removal, nitrous oxide (N₂O) emission and microbial community in sequencing batch and continuous-flow intermittent aeration processes were investigated. Two sequencing batch reactors (SBRs) and two continuous-flow multiple anoxic and aerobic reactors (CMRs) were operated under high dissolved oxygen (DO) (SBR-H and CMR-H) and low DO (SBR-L and CMR-L) concentrations, respectively. Nitrogen removal was enhanced under CMR and low DO conditions (CMR-L). The highest total inorganic nitrogen removal efficiency of 91.5% was achieved. Higher nitrifying and denitrifying activities in SBRs were observed. CMRs possessed higher N₂O emission factors during nitrification in the presence of organics, with the highest N₂O emission factor of 60.7% in CMR-L. SBR and low DO conditions promoted N₂O emission during denitrification. CMR systems had higher microbial diversity. Candidatus Accumulibacter, Nitrosomonadaceae and putative denitrifiers (N₂O reducers and producers) were responsible for N₂O emission.

연속흐름반응조에서 바이오필름형태의 탈염소화 미생물에 의한 TCE분해 모니터링

박선화,한경진,홍의전,안홍일,김남희,김현구,김태승,김영,Park, Sunhwa,Han, Kyungjin,Hong, Uijeon,Ahn, Hongil,Kim, Namhee,Kim, Hyunkoo,Kim, Taeseung,Kim, Young 한국지하수토양환경학회 2012 지하수토양환경 Vol.17 No.5

A 1.28 L-batch reactor and continuous-flow stirred tank reactor (CFSTR) fed with formate and trichloroethene (TCE) were operated for 120 days and 56 days, respectively, to study the effect of formate as electron donor on anaerobic reductive dechlorination (ARD) of TCE to cis-1,2-dichloroethylene (c-DCE), vinyl chloride (VC), and ethylene (ETH). In batch reactor, injected 60 ${\mu}mol$ TCE was completely degraded in the presence of 20% hydrogen gas ($H_2$) in less than 8 days by anaerobic dechlorination mixed-culture (300 mg-soluble protein), Evanite Culture with ability to completely degrade tetrachloroethene (PCE) and -TCE to ETH under anaerobic conditions. Once the formate was used as electron donor instead of hydrogen gas in batch or chemostat system, the TCE-dechlorination rate decreased and acetate production rate increased. It indicates that the concentration of hydrogen produced in both systems is possibly more close to threshold for homoacetogenesis process. Soluble protein concentration of Evanite culture during the batch test increased from 300 mg to 688 mg for 120 days. Through the protein monitoring, we confirmed an increase of microbial population during the reactor operation. In CFSTR test, TCE was fed continuously at 9.9 ppm (75.38 ${\mu}mol/L$) and the influent formate feed concentration increased stepwise from 1.3 mmol/L to 14.3 mmol/L. Injected TCE was accumulated at 18 days of HRT, but TCE was completely degraded at 36 days of HRT without accumulation of the injected-TCE during the left of experiment period, getting $H_2$ from fermentative hydrogen production of injected formate. Although c-DCE was also accumulated for 23 days after beginning of CFSTR operation, it reached steady-state in the presence of excessive formate. We also evaluated microbial dynamic of the culture at different chemical state in the reactor by DGGE (denaturing gradient gel electrophoresis).

CFD 모사 기법을 이용한 유입 유량에 의한 연속 완전혼화 반응조 수리거동 고찰에 관한 연구

이영주(Young Joo Lee),오정익(Jeong Ik Oh),윤석민(Suk Min Yoon),김종오(Jong Oh Kim),박노석(No Suk Park) 大韓環境工學會 2016 대한환경공학회지 Vol.38 No.1

본 연구에서는 수처리 공정에 적용하고 있는 CSTR 반응조를 대상으로 유입 유량이 다양하게 변동하는 경우 반응조내부 수리 거동을 조사하고자 하였다. 유입 유량의 변동은 설계 유량 대비 10~100%까지 변화시켰으며, 각 경우를 CFD 기법을 이용하여 transient 상태의 추적자 실험을 모의하였으며, 모사 결과로부터 2차 정보를 추출하여 수리 거동 지표를 계산하여 유입 유량과 수리거동의 관계를 면밀히 조사하였다. 그 결과, 유입 유량이 증가할수록 Modal index와 β값이 증가하는 거동을 보였으며 Morrill index는 유입 유량과의 관계에서 국부적인 극소값을 가지는 유입 유량이 두 곳 나타났는데 각각 설계유량의 20%되는 지점과 40%가 되는 지점이었다. 두 극소값이 나타나는 유입 유량보다 유량이 증가하면 다시 Morrill index가 증가하는 현상을 보여 이상적인 CSTR 반응조에 근접하는 것으로 나타났다. This paper describes three-dimensional computational fluid dynamics (CFD) simulation of liquid-liquid flow and transient tracer tests in a full-scale continuous stirred-tank reactor (CSTR) used for drinking water treatment. To evaluate the effects of inlet flow rate on hydrodynamic behavior in the selected CSTR, inlet flow rate was changed from 10% to 100% of the design flow rate. From the results of CFD simulation and analysis, as the inlet flow rate increases, Modal index and value are increased. Also, Morrill index shows local minimal points in relation to the inlet flow rate, which are observed at 20% and 40% of the design flow. As inlet flow Increases more than 40%, it is shown that Morrill index re-increases to close to ideal CSTR.

A comprehensive study on wastewater treatment using photo-impinging streams reactor: Continuous treatment

Sayed Javid Royaee,Morteza Sohrabi,Narges Fallah 한국화학공학회 2012 Korean Journal of Chemical Engineering Vol.29 No.11

The degradation of phenol was investigated in a continuous flow impinging streams system. In the first step, statistical experimental designs were used to optimize the process of phenol degradation in a photo-impinging streams reactor. The more important factors affecting phenol degradation (p<0.05) were screened by a two-level Plackett-Burman design. Four of the latter parameters, namely phenol concentration, catalyst loading, pH and slurry flow rate,were selected for final process optimization, applying central composite design (CCD). The predicted data showed that the maximum removal efficiency of phenol (99%) could be obtained under the optimum operating conditions (phenol concentration=50 mg l−1, catalyst loading=2.1 g l−1, pH 6.2 and slurry flow rate=550ml min−1). These predicted values were then verified by certain validating experiments. A good correlation was observed between the predicted data and those determined by the experimental study. This may confirm the validity of the statistical optimum strategy. Finally,continuous degradation of phenol was performed, and the results indicated a higher efficiency and an increased performance capability of the present reactor in comparison with the conventional processes.

Continuous synthesis of silver plates in a continuous stirring tank reactor (CSTR)

Zengmin Tang,김우식,유태경 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.66 No.-

In this report, a continuous stirring tank reactor (CSTR) and batch reactor were used for synthesis of silver (Ag) plates. The influences of agitation speed, molar ratio of AgNO3 to NaCl, and concentration of reagent were investigated. Size analysis demonstrated that the size of Ag plates synthesized by the CSTR was larger than the size of plates synthesized by the batch reactor. The reason might be that low concentration of reagent and continuous supply of monomer in CSTR are more favorable for growth of anisotropic structures. CSTR demonstrates good advantages for mass synthesis of Ag plates of large size.

Microwave-assisted continuous-flow synthesis of mixed-ligand UiO-66(Zr) frameworks and their application to toluene adsorption

The Ky Vo,Van Nhieu Le,Van Cuong Nguyen,Mugeun Song,Daekeun Kim,Kye Sang Yoo,Bum Jun Park,Jinsoo Kim 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.86 No.-

Mixed-ligand metal–organic frameworks (MIXMOFs) containing two or more organic linkers that exhibitfunctionalities can show improved selective gas adsorption and separation properties with respect tothose of the conventional MOFs. In this study, the mixed-ligand UiO–66(Zr) framework was rapidlyprepared by employing a microwave-assisted continuous-flow method, which can be easily scaled up forefficient mass production. A microfluidic syringe pump system was used to introduce the precursorsolutions of zirconium metal salt and ligand mixture (terephthalic acid and 2-amino terephthalic acid)into a polytetrafluoroethylene tubular reactor kept under microwave irradiation. MIXMOFs wereobtained within 10 min, a much shorter time than the reaction time required by the conventional heatingmethod. The prepared samples were characterized by N2 porosimetry,field-emission scanning electronmicroscopy, Fourier transform infrared spectrometry, thermogravimetric, and powder X-ray diffractionanalyses to elucidate the effects of the ligand ratios. Furthermore, the toluene adsorption–desorptiontests were conducted using the synthesized mixed-ligand UiO–66(Zr) adsorbents at differenttemperatures.

Catalytic dehydration of glucose to 5-HMF using heterogeneous solid catalysts in a biphasic continuous-flow tubular reactor

Sadra Souzanchi,Laleh Nazari,Kasanneni Tirumala Venkateswara Rao,Zhongshun Yuan,Zhongchao Tan,Chunbao Charles Xu 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.101 No.-

This work aimed to produce 5-hydroxymethylfurfural (5-HMF) from glucose in a biphasic continuousflowtubular reactor with various heterogeneous solid acid catalysts or combined solid acid-base catalysts. Among the catalysts tested, niobium phosphate (NbP) was found to be the most active catalystfor glucose dehydration with a maximum 5-HMF yield of 45% at 150 C. The higher activity of NbPwas attributed to its higher total number of acid sites and BET surface area, as well as the presence of bothLewis acid and Brønsted acid sites. The effects of different operating conditions such as aqueous toorganic (A/O) phase ratio, reaction temperature and feeding flow rate on the activity of some selected catalystswere studied. Reducing A/O ratio by increasing the extracting organic phase flow rate and increasingthe reaction temperature (up to 150 C) were found to positively affect 5-HMF production fromglucose in the presence of NbP. Kinetics study demonstrated that the overall reaction of glucose dehydrationto 5-HMF over the NbP catalyst is a first-order reaction with the reaction rate constants (k) determinedas 0.06, 0.21 and 0.6 min 1 at 110, 130 and 150 C, respectively, and the apparent activationenergy (Ea) calculated to be 77 kJ/mol.