Valve manifold arrangement

All drum filters (except the single-compartment filter) utilize a rotary-valve arrangement in the drum-axis support trunnion to facih-tate removal of filtrate and wash hquid and to allow introduction of air or gas for cake blowback if needed. The valve controls the relative duration of each cycle as well as providing dead portions of the cycle through the use of bridge blocks. A typical valve design is shown in Fig. 18-121. Internal piping manifolds connect the valve with various sections of the drum. 

Discharge piping must be sized for low pressure drop at maximum flow not only from any one valve, but for the combined flow possibilities in the discharge collection manifold all the w ay to the vent release point, whether it be a flare, incinerator, absorber or other arrangement [13]. See Figures 7-20 illustrations. 

We have demonstrated in this paper that two and four samples can be extracted in parallel with supercritical carbon dioxide without significant impact on data quality. Modifications made to an off-line extractor involved addition of a multiport manifold for the distribution of supercritical fluid to four extraction vessels and of a 12-port, two-way switching valve that allowed collection of two fractions per sample in unattended operation. The only limitation that we have experienced with the four-vessel extraction system was in the duration of the extraction. When working with 2-mL extraction vessels and 50-/zm restrictors, and using the pressure/temperature conditions mentioned above, the 250-mL syringe pump allows us a maximum extraction time of 60 min. During this time, two 30-min fractions can be collected with the present arrangement. 

B, manifold-mounted valves arranged in banks of 3 C, integrated 750 /tL stepper motor driven syringe pump D, linear worm drive E, stirrer stepper motor F, pressure release and pump check valves G, external sample port and 10 cm scale. 

Access to valve headwheels and instruments will influence piping arrangement around heat exchangers. Valve handwheels should be accessible from grade and from a convenient access way. These access ways should be used for arranging manifolds, control valves and instruments. 

In addition to the use of immobilized enzymes on suitable supports, which results in decreased costs in routine analyses, the solid forms of these biocatalysts provide a number of additional advantages, the most immediate of which are (1) simplification of the FI manifold required (use of an additional channel with a point of merging with the sample stream or an additional valve for simultaneous sample-enzyme injection is thus avoided) and (2) increased sensitivity as a result of the lower dilution of the sample on mixing with the enzyme solution. This latter advantage is even more apparent when several enzymatic steps involving different biocatalysts are required to obtain a measurable product. A serial arrangement of as many reactors as steps to be developed is very useful for this purpose. Immuno-reactors with either membranes or magnetic particles as the solid phase for the bovmd antibodies can also be used. 

In order to nummize the volume associated with interconnections and to come to a robust setup, a vertical arrangement of elem s is chosen [3] The construction of three-dimensional flow manifolds out of planar structures allows for a maximum flexibihty in the interconnection of the elements Instead of using valves to mtroduce samples mto the system, multiple pumps are used to control the flow in the system Although this mcreases the number of pumps required compared to a normal Flow Injection Analysis (FLA) system, it ehmmates the need for a micromachined sample mjection valve that is more difficult to realize... 

HIPS are critical safety systems, essentially replacing pressure relief and/ or flare systems. These systems are used to provide overpressure protection and/or flare load mitigation for process equipment, pipelines, wellhead flowlines, gas manifolds, or other special purpose applications. Technically HIPS is a safety instrumented function that consists of a set of components, such as sensors, logic solvers, and final control elements (e.g., valves), arranged for the purpose of taking the process to a safe state when predetermined conditions are violated. The HIPS shall operate independently and be completely separate from the basic process control system (BPCS). 

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