STRATCO®Contactor™ reactor

Fig. 11. Stratco Contactor reactor used in sulfuric acid-catalyzed alkylation (12).

Pryor, P., Peterson, R., Gody, T, and Lin, Y. (2002) STRATCO Contactor reactor performance upgrade - alkylation tube insert technology. Available at http //www2.dupont.com/ Clean Technologies/es MX/assets/down-loads/2002 STRATCO NPRA AM Paper. pdf. 

HF alkylation reactors have undergone more drastic changes than H2S04 reactors. In the middle 1950 s a Stratco contactor similar to that for H2S04 alkylation was used. Later a vertical reactor was developed in which the reactants were bubbled up through liquid HF. Cooling was... 

The alkylation reactors used in the pilot unit operation and also the commercial operation were Stratco Contactors. However, the writer knows of no reason, and no evidence is available, to indicate that any other type reactor, such as the cascade and pump and time tank, would not be satisfactory. It is believed that they would give at least as good results with SARP as without SARP for the same operating conditions and olefin feed stock, and of course with a much lower acid consumption. 

When two or more reactors are used in a refinery, each reactor can be operated with acids of different strengths. If three reactors were used with the acid flowing in series through them, the acidity levels would often be approximately 96, 93, and 90% in the three reactors. If, however, parallel acid flows were employed in the first two reactors and the exit acids from these two reactors were used as the feed acid to the third reactor, benefits would often occur relative to acid consumption and alkylate quality. Stratco Contactors because of their smaller production capacities are easier to adapt to such techniques than cascade reactors, which tend to have larger capacities. 

Stratco Reactors. These reactors designed by Stratco, Inc. produce about 34% of the alkylate produced worldwide (P. Pyror, personal communication). In 2003, Stratco was purchased by E.I. du Pont de Nemours, Inc. A reactor, often called a Contactor, is a horizontal cylindrical vessel, as shown in Fig. 1, with the following features. An impeller at one end recirculates the acid/hydrocarbon dispersion many times (on average) over a U-tube bundle to regulate the temperature of the dispersion at about 5-10°C. A cylindrical circulation shell located in the reactor provides an annular space so that the dispersion flows from one end of the reactor to the other, where it makes a 180° turn and flows back over the tube bundle. 

Fig. 1. Alkylation reactor (or Contactor) in the Stratco process of (A) Tube bundle (B) shell (C) circulation tube (D) impeller (E) hydraulic head and (f) difiCuser vanes.

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