Operating capacity

In 1989 chlorine was produced by 25 companies at 52 locations in the United States (Table 4). Approximately half of these plants are located in the Southeast (Eig. 2). Two companies, Dow Chemical USA and Occidental Chemical Corporation, accounted for 54.3% of the total operating capacity the top five companies accounted for 77.5%. Although 0.8 million tons per year of chlorine capacity is presendy idle (Table 4), announced expansions are expected to bring an additional 660,000 t of new chlorine capacity onstream by 1992, increasing total capacity by about 6%/yr (Table 5). 

Table 10. Operating Capacities and Characteristics of OxyTech Diaphragm Cells...

SPA Catalyst. The sohd phosphoric acid (SPA) catalyst process has been the domiaant source of cumene siace the 1930s. This process accounts for more than 90% of cumene operating capacity (59). A simplified process flow diagram is given ia Figure 5. 

Many different designs are available, the major difference among them being in feed-distribution methods and plate configurations. Operating capacities range from 1 to 3 m of feed/h/m" of projected horizont area [0.4 to 1.2 gal/(min ft)]. 

Select a design Q vapor rate as a percent of the MOC (maximum operating capacity) of the packing. 

Pressure drop should not exceed at maximum operating capacity [94] [139] ... 

Reduced operating capacity due to iron fouling of the resin, which occurs because soluble iron (in the form of ferrous bicarbon-... 

Reduced operating capacity due to physical resin breakdown. 

Most types of ion-exchange resin suffer some breakdown and volume loss over time because of attrition, excessive heat, or other factors. Water softeners should be inspected annually, and a double backwash procedure should be provided. This generally lifts the broken resin ( fines ) to the top of the bed, where it can be removed and replaced to restore capacity. Allow for 5 to 10% resin operating capacity loss per year because of physical breakdown. At many sites the resin is unfortunately not inspected regularly but merely replaced when a serious decline in operating capacity is noticed. Here a resin life expectancy of, say, 6 to 8 years probably is the norm. 

Hard, attrition-resistant, insoluble synthetic polymers (typically a copolymer of styrene with divinylbenzene). The resins are manufactured in a spherical bead shape that contain either exchangeable anion or cation portions, capable of exchanging with other anions or cations and usually in an aqueous medium. Typically cation resins for water softening will have a practical operating capacity of 20,000 gpg (at 6 lb NaCl per cu ft) rising to 30,000 gpg (at 15 lb NaCl per cu ft). 

A recent census of a large number of these small contracting groups listed more than 100 different product development fxmctions. Many of these entities refer to themselves as CROs, but they are often small consultancies that offer a wide variety of services. Careful assessment of these service providers is necessary, as they may have a limited financial depth and operational capacity. On the plus side their fees usually are priced in the con-sulhng range, as they have low overhead, and they may provide the customer with a high degree of expert, personalized service. 

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