Steam cracking diagram

Based on the foregoing considerations, it can therefore be infen that a decrease in the tube diameter, which causes a reduction in residence ime, results in a higher ethylene yield (diagram a in Fig. 2.12) in industrial naphtha steam cracking conditions. Simultaneously, a drop in the propylene yield (diagram b in Fig. 2.12) is observed in the normal... 

By use of an overall steady-state material balance determine whether or not the petrochemical process indicated in Fig. P2.1 has been properly formulated. The block diagrams represent the steam cracking of naphtha into various products, and all flows are on an annual basis (i.e., per year),... 

Figure 3.43 Flow diagram for steam cracking of naphtha...

A typical ethane cracker has several identical pyrolysis furnaces in which fresh ethane feed and recycled ethane are cracked with steam as a diluent. Figure 3-12 is a block diagram for ethylene from ethane. The outlet temperature is usually in the 800°C range. The furnace effluent is quenched in a heat exchanger and further cooled by direct contact in a water quench tower where steam is condensed and recycled to the pyrolysis furnace. After the cracked gas is treated to remove acid gases, hydrogen and methane are separated from the pyrolysis products in the demethanizer. The effluent is then treated to remove acetylene, and ethylene is separated from ethane and heavier in the ethylene fractionator. The bottom fraction is separated in the deethanizer into ethane and fraction. Ethane is then recycled to the pyrolysis furnace. 

Flow diagram of the process for hydrogen and distillate fuel production from residual oil using iron oxides and steam. 1 = Cracking reactor, 2 = distillation column, 3 = hydrogen generator, and 4 = hydrodesulfurization reactor. 

The following example illustrates one particular quantitative application of compensation behavior for the comparison of levels of activity between different systems. The Arrhenius parameters for the steam reformation reaction over nickel alumina catalysts (290) are log A = 17.25 and E = 29.0. The position of this point on compensation diagrams would appear to be more realistically represented by the compensation relation found for oxidation and exchange processes on nickel oxide (Table V, G) than that for cracking on the metal (Table I, A). One possible mechanistic explanation for this distinction is that the active catalyst is an oxide phase [possibly including NiAl204 (290)1... 

Olefin metathesis is a useful reaction for the production of propylene from ethylene and butenes using certain transition-metal compound catalysts. The two main equilibrium reactions that take place simultaneously are metathesis and isomerization. Metathesis transforms the carbon-carbon double bond, a functional group that is unreactive toward many reagents that react with many other functional groups. New carbon-carbon double bonds are formed at or near room temperature even in aqueous media from starting materials. Because olefin metathesis is a reversible reaction, propylene can be produced from ethylene and butene-2. Metathesis can be added to steam crackers to enhance the production of propylene by the transformation of ethylene and the cracking of mixed butenes. Fig. 3 shows a schematic flow diagram of a typical metathesis process. Examples of metathesis... 

Figure 3.35 shows a process flow diagram of Phillips MTBE/ETBE/TAME process. This process is often called the Phillips Etherification Process. The reaction section (1,2) which receives methanol and isobutene concentrate, contains an ion exchange resin. The isobutene concentrate may be mixed olefins from a Fluid Catalytic Cracking Unit (FCCU) or steam cracker or from the on-purpose dehydration of isobutene (Phillips STAR process). High purity MTBE (99 wt%) is removed as a bottoms product from the MTBE fractionator (3). AH of the unreacted methanol is taken overhead, sent to a methanol... 

As the scale continues to develop on the surface the conditions will be modified. For instance, if the deposit layer is porous or contains fissures, it is possible for steam to be generated within the deposit, sometimes referred to as wick boiling, although the phenomenon may be more associated with corrosion deposits. Macbeth [1971] observed steam issuing from cracks in a deposit which he termed "steam chimneys". A schematic diagram is presented as Fig. 8.16. Such a condition would give rise to a different pattern of scale formation. 

Fired-tube furnaces (or heaters) are widely used in the process industries to heat process streams and to crack high-molecular-weight hydrocarbon feeds, in order to produce more valuable lower-molecular-weight compounds. In this case study, we consider a fired-tube furnace used to heat a liquid hydrocarbon feed steam that passes through the furnace in a set of tubes. A simplified schematic diagram is shown in Fig. 13.8. The combustion of the fuel gas (FG) generates heat, which is transferred to the hydrocarbon (HC). The major gaseous combustion reactions in the furnace are... 

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