Systems and methods of dehydrogenating a hydrocarbon in a fixed bed dehydrogenation unit. A method for dehydrogenating a hydrocarbon is applied to a fixed bed reactor. The hydrocarbon flows to a fixed bed reactor to be dehydrogenated in presence of a catalyst in the fixed bed reactor. The catalyst in the fixed bed reactor is then regenerated. The period for dehydrogenation, the period for catalyst regeneration and the period for total slack time are controlled such that total slack time is less than both half of the period for dehydrogenation and half of the period for regeneration. One of the advantages of the process comes from optimization of the slack time, thereby increasing the catalyst utilization rate and number of reactors concurrently online.

Provided is a fuel-reforming device comprising: an ammonia tank (4); a reformer (5) for reforming ammonia and generating high-concentration hydrogen gas having a hydrogen content of at least 99%; a mixing tank (7) for mixing ammonia and hydrogen for temporary storage; and a control means (10) for controlling the respective supply amounts of ammonia and high-concentration hydrogen gas that are supplied to the mixing tank (7). The control means (10) calculates the combustion rate coefficient C of mixed gas with respect to a reference fuel on the basis of equation (1). Equation (1): S.sub.0=S.sub.H×C+S.sub.A×(1−C). In equation (1), S.sub.0 is the combustion rate of the reference fuel, S.sub.H is the combustion rate of hydrogen, S.sub.A is the combustion rate of ammonia, and C is the combustion rate coefficient of mixed gas. In addition, on the basis of equation (2), the control means (10) determines the volume fractions of ammonia and hydrogen that are supplied to the mixing tank. Equation (2): C=1−exp(−A×M.sub.B). In equation (2), M is the volume fraction of hydrogen in mixed gas, and A and B are constants.

In a urea synthesis process, temperature distribution in a submerged condenser is reduced. The process includes: synthesizing urea from NH.sub.3 and CO.sub.2 to generate a urea synthesis solution; by heating the solution, decomposing ammonium carbamate and separating a gaseous mixture containing NH.sub.3 and CO.sub.2 from the solution to obtain a solution higher in urea concentration than the solution obtained in the synthesizing; with use of a submerged condenser including a shell and tube heat exchange structure including a U-tube, absorbing and condensing at least a part of the gaseous mixture in an absorption medium on a shell side, and generating steam on a tube side with use of heat generated during the condensation; and recycling at least a part of liquid, obtained from the shell side, to the synthesizing, wherein water is supplied to the tube side of the condenser at a mass flow rate that is three times or more of the steam generation rate.

Proposed is a process for producing methanol from synthesis gas by means of multi-stage, for example two-stage, heterogeneously catalyzed methanol synthesis, wherein the methanol product formed in every synthesis stage is separated by condensation and the remaining residual gas is supplied to the downstream synthesis stage or after separation of a purge stream recycled to the first synthesis stage as a recycle stream. According to the invention after each synthesis stage the residual gas streams have separated from them a respective purge stream, from which, using one or more hydrogen recovery apparatuses, hydrogen is separated and recycled to the first synthesis stage. The ratio of the individual purge streams and their total molar flow may optionally be varied to allow better control of the reaction in the individual synthesis stages and to allow reaction to the advancing deactivation of the catalysts present therein.

The present application relates to an apparatus and process for producing dimethyl carbonate, in particular a system (apparatus or process) for DMC synthesis without the need of using a dehydrating agent. More particularly, the feed mixture for the process can be selected from the following options: a) carbon monoxide, methanol and flue gas from the process, b) synthesis gas without CO.sub.2 and flue gas from the process, c) synthesis gas with CO.sub.2 and added synthesis gas from purified flue gas from the process. The process uses a catalyst cluster comprising a specific combination of different groups of heterogeneous catalysts wherein each group has a different function. Also the invention relates to an apparatus comprising a specific combination of heterogeneous catalysts for applying different routes to produce dimethyl carbonate from each feed mixture option, on continuous basis.

A system and method is disclosed for efficiently sulfiding metal catalyst resident in a reactor vessel comprises a sulfiding module and a hydrogen sulfide detection module and a remote computer all arranged and configured to communicate wirelessly and to allow remote control and monitoring of the modules and sulfiding process.

Systems are provided that permit temperature control of a catalyst bed for conversion of alcohols to fuel hydrocarbons by modulating the water content of the alcohol feed stream provided to the catalyst bed. In some embodiments a secondary catalyst bed is provided for the conversion of light hydrocarbons found in the initial hydrocarbon product to fuel hydrocarbons that are liquid at ambient temperature and pressure.

Disclosed is a cost-effective process for catalytic conversion of simple C.sub.6-based sugars (such as glucose and fructose) and industrial-grade sugar syrups derived from starch (such as different grades of High Fructose Corn Syrup) and cellulosic biomass to 5-HydroxyMethylFurfural (5-HMF) in a continuous-flow tubular reactor in bi-phasic media using inexpensive heterogeneous solid catalysts. Commercial and synthesized heterogeneous solid catalysts were used and their activities in terms of sugar conversion and HMF selectivity and yield were compared. Continuous dehydration of fructose, glucose and industrial-grade sugar syrups derived from corn and wood to HMF was achieved and the stability of selected catalysts and feasibility of catalyst recycling and regeneration were demonstrated. The performance of the catalysts and reactor system were examined under different operating conditions including reaction temperature, feeding flow rate, initial feedstock concentration, catalyst loading, presence of extracting organic solvent and phase transfer catalyst and aqueous to organic phase ratio. At the best operating conditions, HMF yield attained 60%, 45% and 53%, from dehydration of fructose, glucose and HFCS-90, respectively.

The treatment plant comprises: a reactor for the sublimation of organic material in order to obtain a syngas; a filtration assembly for filtering the syngas in order to obtain a filtered gas, and a motor-generator assembly for producing electrical energy by means of the combustion of the filtered gas and thereby producing burnt gas; characterized in that said plant also comprises a methanation assembly, comprising: a catalyst that can extract carbon dioxide and nitrogen from the burnt gas; an electrolyzer that can separate water into oxygen and hydrogen by means of electrolysis; and a methanation reactor, which can produce methane by means of the Sabatier reaction using hydrogen and carbon dioxide originating from the electrolyzer and from the catalyst; the catalyst comprising a catalysis layer consisting of stone wool and nickel nanospheres, a plurality of steel microtubes containing copper microfilaments, and a system for controlling the reaction conditions.

The present invention relates to a micro-interface strengthening reaction system and method for heavy oil hydrogenation preparation of ship fuel, including a liquid phase feed unit, a gas phase feed unit, a micro-interface generator, a fixed-bed reactor and a separation tank. The present invention may reduce the pressure during the reaction by 10-80% while ensuring the efficiency of the reaction by breaking the gas to form micro-sized micro-bubbles and making the micro-bubbles mix with heavy oil to form an emulsion to increase the area between the gas and the liquid phase and to achieve the effect of enhancing mass transfer in a lower preset range. And, the present invention greatly enhances the mass transfer, so that the gas-liquid ratio can be greatly reduced. Also, the method of the present invention has low process severity, high production safety, low product cost per ton, and strong market competitiveness.