Ethylene plant flow schematic

Fig. 51eft. Schematic flow diagram of an ethylene plant using naphtha feedstock. CW = cooling water QW = quench water QO = quench oil LPS = low pressure steam MPS = medium pressure steam SPS = super high pressure steam C3R = propylene refrigerant and...

Ethane is converted to ethylene, a valuable monomer, via pyrolysis. The one-pass conversion efficiency of ethane ranges from 40 to 70% depending on operating conditions of a particular facility but can be easily set to a desired value by controlling the temperature of the reaction. If ethane is not recycled within the plant, it must be sent to a flare and be wasted. The flow schematic for the process is shown in Figure 111. 

Fig. 4 represents a simplified schematic flow diagram for an ethane and/or propane cracking ethylene plant. The separation sequences are shown as follows ... 

Fig. 4 Simplified schematic flow diagram for a typical ethane/propane cracking ethylene plant.

In a typical balanced plant producing vinyl chloride from EDC, all the HCl produced in EDC pyrolysis is used as the feed for oxychlorination. On this basis, EDC production is about evenly spHt between direct chlorination and oxychlorination, and there is no net production or consumption of HCl. The three principal operating steps used in the balanced process for ethylene-based vinyl chloride production are shown in the block flow diagram in Eigure 1, and a schematic of the overall process for a conventional plant is shown in Eigure 2 (76). A typical material balance for this process is given in Table 2. 

Air-Based Direct Oxidation Process. A schematic flow diagram of the air-based ethylene oxide process is shown in Figure 2. Pubhshed information on the detailed evolution of commercial ethylene oxide processes is very scanty, and Figure 2 does not necessarily correspond to the actual equipment or process employed in any modem ethylene oxide plant. Precise information regarding process technology is proprietary. However, Figure 2 does illustrate all the saUent concepts involved in the manufacturing process. The process can be conveniently divided into three primary sections reaction system, oxide recovery, and oxide purification. 

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