Wonjun Cho

Simulation of commercial dimethyl ether production plant

The process of Dimethyl ether(DME) production consists of the four parts which are syngas synthesis from natural gas, absorbing CO2 from syngas, DME synthesis reactor and DME separation/purification. KOGAS has developed a process in which syngas is produced from natural gas and converted to DME using a single reactor[1]. For the construction of commercial scale DME plant, the modeling of one-step DME synthesis reactor is required prior to beginning the construction. Since then, the simulation of DME production process should represent actual operation data of pilot or demo scale plant. The simulations of reactor had been conducted using a one-dimensional steady-state model of a shell-and-tube type fixed-bed reactor[2]. Using the result of a reactor analysis, we have conducted simulations of all processes using steady-state models in Aspen Plus®. The simulation of process in this paper reflects the result of a reactor simulation and the real operation data of demo scale DME plant. And the simulation results are satisfied with the requirements for the basic design and engineering of commercial DME plant construction.

Optimization of KOGAS DME Process From Demonstration Long-Term Test

Dimethyl ether (DME) is a new clean fuel as an environmentally-benign energy resource. DME can be manufactured from various energy sources including natural gas, coal, and biomass. In addition to its environmentally friendly properties, DME has similar characteristics to those of LPG. The aim of this article is to represent the development of new DME process with KOGAS`s own technologies. KOGAS has investigated and developed new innovative DME synthesis process from synthesis gas in gaseous phase fixed bed reactor. DME has been traditionally produced by the dehydration of methanol which is produced from syngas, a product of natural gas reforming. This traditional process is thus called the two-step method of preparing DME. However, DME can also be manufactured directly from syngas (single-step). The single-step method needs only one reactor for the synthesis of DME, instead of two for the two-step process. It can also alleviate the thermodynamic limitations associated with the synthesis of methanol, by converting the produced methanol into DME, thereby potentially enhancing the overall conversion of syngas into DME. KOGAS had launched the 10 ton/day DME demonstration plant project in 2004 at Incheon KOGAS LNG terminal. In the mid of 2008, KOGAS had finished the construction of this plant and has successively finished the demonstration plant operation. And since 2008, we have established the basic design of commercial plant which can produce 3,000 ton/day DME.

CO2 Conversion to Chemicals and Fuel for Carbon Utilization

Recent direction dealing with climate change has changed more to focus on carbon utilization rather than the direct carbon capture and storage. Conceptually converting CO 2 to sellable chemicals or fuels should be more benign to environment by substituting the fossil raw materials like oil, natural gas, or coal. Instead of converting CO 2 fully to valuable chemicals or fuels, it is much easier to employ a portion of CO 2 with existing raw materials in many natural gas conversion processes. Dimethyl ether (DME) and gas-toliquids (GTL) are most prominent processes that can be modified to accommodate CO 2 as a reacting raw material. There are already several successful technology developments in using CO 2 -rich natural gas for DME and liquid fuels, although they are not yet fully reached the commercialized level. This chapter highlights recent developments in utilizing CO 2 -containing natural gas and landfill gas to yield valuable chemicals and fuels like diesel or DME.

Stage IV Wilms Tumor Treated by Korean Medicine, Hyperthermia and Thymosin-α1: A Case Report

Introduction: Wilms tumor is one of general solid cancers that occur in children, which carries a death rate of 7-8 in a million. The cure rate of Wilms tumor in the recent 30 years has dramatically been improved, but a proper remedy is still not prepared enough in terms of application in tumor therapy upon recurrence after radiotherapy, surgery and chemotherapy. We present an integrative medical remedy - hyperthermia and thymosin-α1 treatment focused on herbal remedy - since there have been cases in which this remedy contributed to remission in the liver-transferred part in the 4th phase of Wilms tumor and stable maintenance of metastatic lung lesion. Case Presentation: Our patient, a female Korean mongoloid outpatient, was treated from October 25, 2014, to July 22, 2015. The herbal remedy consisted of 8 ml inhalation of Soram nebulizer solution q.d., Soramdan S 8 g p.o., Hangamdan S 1 g p.o., t.i.d., Cheongjangtang 10-30 ml, and Spiam HC 8 g p.o. The integrative medical therapy was done with hyperthermia therapy (oncothermia) and 1.6 mg of thymosin-α1 treatment (Zadaxin) i.m. According to the CT result on July 15th, 2015, the liver metastasis was not seen anymore, while the lung metastasis was maintained stably without tumor progress. Conclusions: Accompanying integrative medical therapy with herbal remedy in the treatment of Wilms tumor showing progress patterns after surgery and chemotherapy can be meaningful as a new remedy.

The Effect of Promotor and Reaction Condition for FT Oil Synthesis over 12wt% Co-based Catalyst

Abstract >> The synthesis of Fischer-Tropsch oil is the catalytic hydrogenation of CO to give a range of products,which can be used for the production of high-quality diesel fuel, gasoline and linear chemicals. Our cobalt basedcatalyst was prepared Co/alumina, silica and titania by the incipient wet impregnation of the nitrates of cobalt and promoter with supports. Cobalt catalysts was calcined at 350°C before being loaded into the FT reactors. Afterthe reduction of catalyst has been carried out under 450°C for 24hrs, FT reaction of the catalyst has been carriedout at GHSV of 4,000/hr under 200°C and 20atm. From these test results, we have obtained the results as following; in case of 12wt% Co-supported Al 2 O 3 , SiO 2 and TiO 2 catalysts, maximum activities of the catalysts were appearedat the promoters of Mn, Mo and Ce respectively. The activity of 12wt% Co/Al 2 O 3 added a Mn promoter wasabout 3 times as high as that of 12wt% Co/Al 2 O 3 catalyst without promoters. When it has been the experiment at the range of reaction temperature of 200~220°C and GHSV of 1,546~5,000/hr, the results have shown generallyincreasing the activities with the increase of reaction temperature and GHSV.

Preliminary Feasibility Study for Commercial DME Plant Project

Abstract >> Dimethyl ether (DME) is a new clean fuel as an environmentally-being energy resources. DME hassimilar characteristics to those of LPG and can be substituted Diesel fuel. KOGAS has investigated and developednew innovative DME synthesis process from synthesis gas with KOGASs own technologies. KOGAS had finished the construction of 10ton/day DME demonstration plant in 2008, we have established the basic design of commercial plant which can produce 3,000ton/day DME. Specifically, an economic model for a commercial DME project willbe presented. It accounts for all the major cost factors that are considered in a commercial scale project as themodel input for performing cash flow analysis, after which key economic indicators are produced including the internal rate of return (IRR), net present value (NPV). Sensitivity analysis is performed to identify dominant costfactors to the project economics and quantify their impact. The inputs to the economic analysis will be basedon representative cost factors from the commercial-scale design of KOGAS’ direct DME process supplementedby literature data. Case study results will be presented based on recent commercialization projects.

Analysis of the Fixed Bed Reactor for DME Synthesis

DME is considered as one of the most promising candidates for the substitute of LPG and diesel fuel. We analyzed one-step DME synthesis from sysngas in a fixed bed reactor with consideration of the heat and mass transfer between catalyst pellet and reactants gas and effectiveness factor of catalysts together with reactor cooling through reactor wall. Simulation results show effects of pore diffusion, arrangement of catalysts and heat transfer on the performance of the reactor

Methane activation of plasma and catalytic reaction

Summary form only given, as follows. Conversion of methane to higher hydrocarbon products was investigated through the microwave and RF plasma catalytic reaction. In this study, various experiments have been conducted to find out the effects of parameters on the high frequency region, that was a microwave of 2.45GHz and radio frequency of 13.56 MHz. Manufacturing of C2 products and higher hydrocarbons was carried out by two kinds of discharge equipment and nonoxidative and oxidative coupling of methane. In the microwave plasma catalytic reaction, C2+ products have been obtained much more due to many free radicals produced at low plasma power. Also natural gas containing a little amount of ethane and propane is more active reactant, producing more C2+ products such as ethane, ethylene and acetylene than methane.