Section 6.13 PFTR Bubble Reactor

Cost as a process vessel, Section 10.1, plus the components used for the specific design sparger, circulating pump. Section 2.3, ejector. Section 6.4, agitator. Section 7.1. 

Ozone generation from air, with air preparation equipment, ozone generator, dissolution equipment, off-gas recycling or destruction equipment, safety and monitoring equipment. FOB cost = 545 000 at ozone production rate of 0.46 g/s with n = 0.67 for the range 0.09-30. Factors air feed, X 1.00 oxygen feed, X 0.5. L-rM = 1.2-1.35. 

Ozone contact chamber, reinforced concrete, baffles and cover, installed excluding ozone generation. PM cost = 82 000 at liquid volume = 90 m with n = 0.61 for the range 13-2600. 

Gas sparger, air diffuser only unit price for 5.3 m sections of 23 cm diameter sparger including fittings to connect into gallery but excluding pipe to compressor or blower, FOB cost 12 000 for sparger surface area = 3.5 m, n = 1.0 12 000 for gas flow rate = 94 dm s, n = 1. 

Aeration, sparger diffused air system including blowers (including one standby blower to ensure reliability), drives, building, air piping, air diffusers but excluding the vessel, installed cost 475 000 at reliable air flow rate of 1.4 m s, n = 0.66 for flow rate 0.05-1.4 and n = 0.93 for flow rate 1.4-23. 

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Gas residence time 0.5 to 1.3 s gas velocity 3 to 10 m/s Re > 10, L/D > 100. To eliminate backmixing, Pe > 100. Liquid residence time 1 to 6 s liquid velocity 1 to 2 m/s Re > 10, L/D > 100. PFTR is smaller and less expensive than CSTR. PFTR is more efhcient/volume than CSTR if the reaction order is positive with simple kinetics. For fast reactions, nse small-diameter empty tube in turbulent flow. For slow reactions, use large-diameter empty tubes in laminar flow. If reaction is complex and a spread in RTD is harmful, consider adding motionless mixer (Section 16.11.6.10). Examples hydrolysis of corn starch to dextrose polymerization of styrene hydrolysis of chlorobenzene to phenol esterification of lactic acid. Gas-liquid see transfer line. Section 16.11.6.9, or bubble reactors. Section 16.11.6.11. Liquid-liquid see transfer line. Section 16.11.6.9, or bubble reactors. Section 16.11.6.11. 

Liquid-liquid creation of drops, see Sections 5.3 and 8.3. Superficial dispersed drop velocity 0.001-0.02 m/s with usual values 5.5 L/s m. This bubble column gives the smallest reactor volume compared with STR. For example, for esterification reactor volume divided by the daily production, m dayfkg. PFTR 0.7 m day/kg. 3 CSTR in series. Section 6.26, 0.85 m day/kg. Batch STR, Section 6.27, 1.04 m/ day/kg. CSTR, Section 6.29, 1.22 m day/kg. 

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