Flow through regeneration unit

Figure 12.2 Simultaneous minimization of fresh water flowrate and total flow through regeneration units (concentration of each contaminant in waste water < 400 ppm), for design of the water network in a petroleum refinery.

In the first step regeneration is back-flowed through the unit, closing the foam park check valves. The foam is compressed toward the front of the vessel, thus squeezing out oil and solids. 

Total Flow Rate through Regeneration Units (t/h)... 

Figure 12.7 Simultaneous minimization of fresh water flow rate and total flow rate through regeneration units, for water network design/revamping for different limits on contaminant concentrations in waste water (CC in WW).

The sour gas, containing small amounts of amine, leaves the top ol the regenerator and flows through a condenser to the accumulator. The sour gas is sent to the sulfur unit, while the condensed liquid is refluxed to the regenerator. 

Reactors of air-lift units are generally similar to previous concurrent-flow TCC design. Steam is used in the seal leg above the reactor. The reactors are operated at pressures from 5 to 15 p.s.i.g. (107,333). Spent catalyst is stripped with steam, in the purge zone in the bottom of the reactor, and then flows through external pipes to the regenerator. These pipes are equipped with shutoff safety valves which are normally wide open. No adjustment can be made at this point to control catalyst flow. 

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