Synthesis gas, compressed

If additional CO is available, it may be added prior to synthesis gas compression or it may be added to the reformer feedstock. Although the advantages of adding CO are significant, the differential economics of the CO addition points is marginal. 

To this end, both Texaco and Shell are developing their processes to handle coal slurries). The Texaco process is somewhat more flexible in that it has commercial operating experience with pressures up to 1200 psig. Thus the Texaco process requires no synthesis gas compression. The Shell process operates generally around 600 psig. Typically, today s POX plant would be around 60% thermally efficient (plus oxygen import) and can operate on cheaper feedstocks. 

Methanolation [744], [745] has been proposed for partially replacing methanation. It converts the residual carbon oxides to methanol, preferably at higher pressure in an intermediate stage of synthesis gas compression. Methanol is removed from the gas by water scrubbing. The methanol may be recycled to the steam reformer feed or recovered as product. As full conversion of the carbon oxides is not achieved, a clean up methanation unit must follow the methanolation section. 

The atmospheric-pressure gasification is a considerable disadvantage of this process route, which substantially increases equipment dimensions and costs, as well as the power required for synthesis gas compression. An energy input of 51.5 GJ/t NIL, (LHV) has been reported. According to [563], the atmospheric ACGP gasifier (Section 4.1.2.3) could lower the consumption to 44 GJ/t NH( (HHV). 

If the pressure of the steam reformer is as low as 20 bar, synthesis gas compression is necessary because the MeOH process cannot operate at this low pressure. 

The loop pressure for a MeOH plant is too high to avoid synthesis gas compression, even when using a combined front-end, unless a substantial methane leakage from the secondary reformer is allowed. 

The reduced operating pressure of the oxygenate synthesis allowed by the introduction of the DME reaction means that the synthesis gas production and the oxygenate process can be operated at the same pressure, thus eliminating the need for synthesis gas compression. Further, the significant reduction of the loop pressure minimises the problems caused by high operating pressure in the MTG process. 

Process flexibility and simplicity are main features of the Integrated Gasoline Synthesis. Yield and quality, cycle length etc. can be adjusted to ensure a desired balance between capital investment and operating costs. Synthesis gas compression can be avoided. This means low investment. Further, the exclusion of the synthesis gas compressor means higher reliability. 

Blaugas Coal Coal briquettes, hot Coal gas, 2.3 Coal gas, compressed, 2.1, 2.3 Coal tar, crude and solvent Coal tar distillates, flammable, 3, 3.2,3.3 Coal tar naphtha Coal tar oil Coke, hot Creosote Creosote (coal tar or wood tar) Creosote salts Cresols (o-, m-, p-), 6.1, 8 Cresols (ortho- meta- para-), liquid or solid, 6.1 Dead oil Fischer Tropsch gas Fischer-Tropsch gas compressed, 2.2 Iron oxide, spent (obtained fix)m coal gas purification), 4.2 Iron sponge, spent, 4.2 Iron sponge, spent (obtained from coal gas purification), 4.2 Prilled coal tar Synthesis gas Synthesis gas, compressed Water gas Water gas, compressed... 

ATR and POX plants can run at much higher pressures. For example, some plants require synthesis gas at about 800 psig this can be supplied directly from an ATR or POX without synthesis gas compression. TEMPERATURE - SMR plants typically run at reformer outlet temperatures of 1550 to 1700°F. 

The final energy input is power for the three gas-compression duties synthesis gas compression, synthesis loop circulation, and ammonia refrigeration. The power required for these duties depends, for example, on synthesis pressure and on converter design. Refrigeration power is strongly dependent on ambient temperature. However, typical figures for a modern 1000 ton per day low-pressure... 

The pressure of the primary reformer has been increased in order to reduce the synthesis gas compression power. The radiant heat load of the reformer has been reduced by increasing the preheat temperatures for both process air and reformer reactants. This in turn reduces the fuel requirement of the reformer. 

Increasing the loop pressure gives a higher equilibrium concentration of ammonia and also increases the rate of reaction. Hence, the maximum production capacity is attained at the maximum operating pressure of the equipment. On the other hand, the synthesis gas compression power is also increased. 

Natural gas is the most common raw material used in the manufacture of methanol More than 75% of all the methanol produced worldwide is produced from natural gas. The flow scheme for a typical large-capacity methanol plant is depicted in Figure 23. The processing steps include feed gas pretreatment, steam reforming, waste heat recovery, synthesis gas compression, methanol synthesis, and distillation. 

For smaller plants, under 600 tons/day, reciprocating compressors still are used. They often contain several services on a common drive shaft air compression, natural gas compression, synthesis gas compression and recycle, and ammonia compression for regrigeration. 

Reforming at higher pressure saves energy due to reduced power requirements for synthesis gas compression. Reduction of the steam to carbon ratio also saves energy due to savings in process steam consumption. In both cases, more severe conditions are required in the reformer to obtain the required high conversion of the feedstock. This has led to the requirement for better catalysts and better materials for the reformer tubes. 

Use of Fluor s proprietary polypropylene carbonate process (see Sect. 6.3.4) for carbon dioxide removal. It is suggested [778] that carbon dioxide removal and methanation be installed after synthesis gas compression. 

---