浆态床一步法二甲醚合成技术研发

在实验室进行了对采用浆态一步法合成二甲醚研究 ,系统考察了各种工艺条件 ,如温度、压力、空速、氢碳比等参数对反应的影响 ,获得了最佳的操作条件 :温度 2 5 0℃～ 2 70℃ ,压力 4～ 5MPa ,空速 30 0 0～ 6 0 0 0ml/g .cat/h ,氢碳比 1∶1,在此基础上进行了 30 0 0t/a的中试实验 ,取得了满意的结果。     

Semi-indirect synthesis of LPG from syngas: Conversion of DME into LPG

Efficient conversion of dimethyl ether (DME) into liquefied petroleum gas (LPG) with a hybrid catalyst is a novel method for semi-indirect synthesis of LPG fuel from syngas. The hybrid catalysts consisting of zeolite and hydrogenation catalyst were investigated in a fixed bed reactor. Experimental results demonstrated that the hybrid catalyst consisting of (Pd/SiO₂) and USY efficiently converted DME into LPG and restrained decomposition of DME into CO and H₂. With that catalyst, the one through conversion of DME reached about 100%, almost no CO and CO₂ were produced and selectivity for LPG was more than 65%.     

Design and operation of integrated pilot-scale dimethyl ether synthesis system via pyrolysis/gasification of corncob

The integrated pilot-scale dimethyl ether (DME) synthesis system from corncob was demonstrated for modernizing utilization of biomass residues. The raw bio-syngas was obtained by the pyrolyzer/gasifier at the yield rate of 40-45 Nm³/h. The content of tar in the raw bio-syngas was decreased to less than 20 mg/Nm³ by high temperature gasification of the pyrolysates under O₂-rich air. More than 70% CO₂ in the raw bio-syngas was removed by pressure-swing adsorption unit (PSA). The bio-syngas (H₂/CO ≈ 1) was catalytically converted to DME in the fixed-bed tubular reactor directly over Cu/Zn/Al/HZSM-5 catalysts. CO conversion and space-time yield of DME were in the range of 82.0-73.6% and 124.3-203.8 kg/m_cat³/h, respectively, with a similar DME selectivity when gas hourly space velocity (GHSV, volumetric flow rate of syngas at STP divided by the volume of catalyst) increased from 650 h⁻¹ to 1500 h⁻¹ at 260 °C and 4.3 MPa. And the selectivity to methanol and products was less than 0.65% under typical synthesis condition. The thermal energy conversion efficiency was ca. 32.0% and about 16.4% carbon in dried corncob was essentially converted to DME with the production cost of ca. ¥ 3737/ton DME. Cu (1 1 1) was assumed to be the active phase for DME synthesis, confirmed by X-ray diffraction (XRD) characterization.     

Simulation of DME synthesis from coal syngas by kinetics model

DME (Dimethyl Ether) has emerged as a clean alternative fuel for diesel. There are largely two methods for DME synthesis. A direct method of DME synthesis has been recently developed that has a more compact process than the indirect method. However, the direct method of DME synthesis has not yet been optimized at the face of its performance: yield and production rate of DME. In this study it is developed a simulation model through a kinetics model of the ASPEN plus simulator, performed to detect operating characteristics of DME direct synthesis. An overall DME synthesis process is referenced by experimental data of 3 ton/day (TPD) coal gasification pilot plant located at IAE in Korea. Supplying condition of DME synthesis model is equivalently set to 80 N/m³ of syngas which is derived from a coal gasification plant. In the simulation it is assumed that the overall DME synthesis process proceeds with steadystate, vapor-solid reaction with DME catalyst. The physical properties of reactants are governed by Soave-Redlich-Kwong (SRK) EOS in this model. A reaction model of DME synthesis is considered that is applied with the LHHW (Langmuir-Hinshelwood Hougen Watson) equation as an adsorption-desorption model on the surface of the DME catalyst. After adjusting the kinetics of the DME synthesis reaction among reactants with experimental data, the kinetics of the governing reactions inner DME reactor are modified and coupled with the entire DME synthesis reaction. For validating simulation results of the DME synthesis model, the obtained simulation results are compared with experimental results: conversion ratio, DME yield and DME production rate. Then, a sensitivity analysis is performed by effects of operating variables such as pressure, temperature of the reactor, void fraction of catalyst and H₂/CO ratio of supplied syngas with modified model. According to simulation results, optimum operating conditions of DME reactor are obtained in the range of 265–275 °C and 60 kg/cm². And DME production rate has a maximum value in the range of 1–1.5 of H₂/CO ratio in the syngas composition.     

合成气一步法制二甲醚基本工艺包设计简介

简单介绍合成气一步法制二甲醚基本工艺包设计,项目的情况和主要内容,突出其"一床双返三塔"新工艺.基于此设计,可按具体情况转化为实施性的二甲醚装置建设工艺包设计.     

H2-based synthetic fuels: A techno-economic comparison of alcohol,ether and hydrocarbon production

Electricity-based fuels are one promising option to achieve the transition of the energy system, and especially the transport sector, in order to minimize the role of fossil energy carriers. One major problem is the lacking compatibility between different techno-economic assessments, such that recommendations regarding the most promising Power-to-Fuel technology are difficult to make. This work provides a technically sound comparison of various Power-to-Fuel options regarding technological maturity and efficiency, as well as cost. The investigated options include methanol, ethanol, butanol, octanol, DME, OME_3-5 and hydrocarbons. To guarantee the comparability, all necessary chemical plants were designed in Aspen Plus® to determine material and energy consumption, as well as investment costs within the same boundary conditions and assumptions in all simulations and calculations. Individual technical aspects of the various synthesis routes, as well as their advantages and disadvantages, are highlighted.With an assumed electrolysis efficiency of 70% and considering the energy demand for the CO₂ supply and the energy and operating material demand of the chemical plants, depending on the selected electrofuel, 30–60% of the primary energy in renewable electricity can be stored in the lower heating value of the electrofuel. In the presented results, the costs of H₂ supply are responsible for 58–83% of the total manufacturing costs and thus have the greatest potential to reduce the latter. For the base case (4.6 €/kg_H2), various electrofuels will have costs of manufacturing of between 1.85 and 3.96 €/l_DE, with DME being the cheapest.     

A techno-economic review of biomass gasification for production of chemicals

Gasification is a thermochemical process which can be used as a low-emission and highly efficient method to produce syngas and chemicals such as biomethanol and dimethyl ether (DME). In this paper, a review of technologies and methods for economic production of chemicals through gasification of biomass and other fuels has been carried out. A variety of techno-economic studies and analysis have been proposed in order to better understand the technical and economic assessments during the biomass gasification. Results showed that the methanol production cost for biomass (wood) is from 195 to 935 €/t, for waste residues is from 200 to 930 €/t, for coal is from 160 to 480 €/t, and for natural gas is from 90 to 290 €/t. It also concluded that fuel (wood) cost has positive linear relationship with ethanol production cost, meaning as the feedstock cost increases from 30 to 50 $/day-ton, the ethanol production cost enhances from 1.66 to 1.95 $/gal.     

Hydrogen generation characteristics of reduced DME steam reforming catalysts according to heating methods

The purpose of this study is to investigate the hydrogen generation characteristics of H₂-reduced dimethyl ether (DME) steam reforming (SR) catalysts using different heating processes. The effects of the H₂ reduction temperature and space velocity were investigated to identify an optimal reaction environment. Both the resistive and induction heating methods were used. The catalysts were prepared by impregnating copper over a γ-Al₂O₃ support. The Cu/Al₂O₃ catalysts with different loading amounts of 5–15 wt% Cu exhibited different characteristics when subjected to hydrogen reduction. The variation in acidity had a dominant effect on the DME-SR activity, and 15Cu/Al₂O₃ that underwent hydrogen reduction treatment at 500 °C attained improved performance at low temperatures and low formation of by-products, allowing for the achievement of its highest H₂ concentration of 74.08% at 375 °C. The induction heating reactor had an energy consumption that was about 25% lower than that of the resistive heating reactor.     

High-throughput architecture for post-quantum DME cryptosystem

Quantum computers have the potential to solve difficult mathematical problems efficiently, therefore meaning an important threat to Public-Key Cryptography (PKC) if large-scale quantum computers are ever built. The goal of Post-Quantum Cryptography (PQC) is to develop cryptosystems that are secure against both classical and quantum computers. DME is a new proposal of quantum-resistant PKC algorithm that was presented for NIST PQC Standardization competition in order to set the next-generation of cryptography standards. DME is a multivariate public key, signature and Key Encapsulation Mechanism (KEM) system based on a new construction of the central maps, that allows the polynomials of the public key to be of an arbitrary degree. In this paper, a high-throughput pipelined architecture of DME is presented and hardware implementations over Xilinx FPGAs have been performed. Experimental results show that the architecture here presented exhibits the lowest execution time and highest throughput when it is compared with other PQC multivariate implementations given in the literature.     

生物质合成燃料二甲醚的技术

介绍和分析了生物质合成气的制备工艺和合成气组分调整工艺，提出了生物质合成液体燃料二甲醚的工艺路线，展望了生物质合成二甲醚技术的前景。