Manifold plate

In order to achieve flexibility, faster development, and to reduce the design and installation cost, a new standard, the ISA/ANSI 76.00.02 was developed [28]. This system defines a modular sample conditioning system that can be assembled on a manifold plate using components that follow the size and connectivity protocols in the ISA/ANSI standard. Companies such as Parker Instrumentation (Jacksonville, AL) (Figure 37.20) and CIRCOR Instrumentation (Joliet, IL) (Figure 37.21) produce pressure reducers, gauges, flow meters, different types of valves, safety devices, and many other components that comply with the footprint and connectivity definitions of the ANSI/IS A 76 standard. 

Use of an internal channel heating system, coupled with the low manifold plate temperature, have enabled torpedoes to be set within the manifold and for them to be used to heat the exit channels. A torpedo is normally fitted in a fixed manner (see Figure 4.93), but there is also the potential to fasten it in such a way that it can move (Figure 4.93b). 

In view of the low temperature of the manifold plate, the sprue bushings must be heated. Both external and internal heating is used (for the use of a torpedo, see Figure 4.92). 

Heater bending usually takes place on bars fastened to the manifold plate tangentially to the groove curvature, and the heater is pushed into the groove with each bending. The minimum bend radius of a tubular heater depends on its diameter and is 5-16 mm [1]. This technique requires a certain amount of experience. 

The cells, fluid manifold plate and positive and negative terminals are sandwiched between upper and lower endplates which are linked by peripheral tie rods. The tie rods provide the compressive load to contain the structure. However, to ensure the load is distributed evenly over the complete cross-sectional area of the module, the upper endplate incorporates a sealed flexible bladder which is pressurized to 20.7-22.4 bar (2.07-2.24 MPa) with nitrogen gas. This ensures that electrical continuity is maintained within the cell module and prevents leakage of gases or liquids either within the module or to the surrounding atmosphere. Typical operating characteristics of the cell stack are... 

Graphite manifold plate with surpentine grooves... 

Eig. 19. CME monopolar electrolyzer a, membrane b, cathode element c, half-cathode element d, current distributor e. Teflon tube f, CI2 + depleted brine manifold g, conductor rod h, CI2 + depleted brine outlet nozzle i, base frame j, recycled NaOH manifold k, recycled NaOH inlet nozzle 1, gasket (the gasket-to-element ratio is quite small) m, tie rod n, anode element o, H2 + NaOH manifold p, end plate, q, under cell bus bar (simplifies piping... 

Eig. 20. Cut view of Chlorine Engineers membrane bag cell a, manifold b, frame c, partition plate d, sealing plug e, recirculated NaOH inlet f, cathode g, anode h, cathode can i, membrane bag j, base k, butterfly valve 1, feed brine m, depleted brine n, caustic outlet. 

ICIFM-21SP Monopolar Electrolyzers. Id s EM-21 SP monopolar electrolyzer incorporates stamped electrodes that are 2 mm thick and of a relatively small (0.2 m ) size (50). The electrolyte compartments are created by molded gaskets between two of the electrode plates the electrode spacing is finite and is estabHshed by gasket thickness. The electrode frames are supported from rails and are compressed between one fixed and one floating end plate by tie rods. Inlet and outlet streams are handled by internal manifolds. A crosscut view of the electrolyzer is shown in Eigure 21. As of 1989, ICI had Hcensed 20 plants having an annual capacity of 468,250 t of NaOH. 

A plate-type filter, the PDF filter (18), uses a paddle wheel with radial, longitudinal plates coveted with filter cloth and manifolded to the filter valve at one end of the vessel, instead of a dmm. This filter uses a horizontal pressure vessel, was built to have only 0.75 or 1.5 m area, and operates at 25 kPa. A central screw conveyor collects the cake blown off the plates and conveys it to the discharge end of the vessel. 

For very low flow rates the orifice plate is often incorporated into a manifold, an integral part of the differential-pressure transmitter. This provides a convenient compact installation. 

The cell head is fabricated from a 2.54-cm steel plate and has separate compartments for fluorine and hydrogen. The oudet-gas manifolds, hydrogen fluoride feed and purge lines, and electrical connections are on top of the head. The gas separation skirt is made of Monel. An insulating gasket maintains the seal between the tank and the head. The anode assembly consists of 32 carbon blades bolted onto a copper bar, each of which contains three copper conductor posts. The cathode assembly consists of three vertical, 0.6-cm parallel steep plates. The plates surround the anode assembly and are supported by three steel posts which also serve as conductors. 

Another type has several flat plates manifolded into a plastic header. The surface of the laminate is suitable for dip-casting membranes, whereas the interior is several orders of magnitude more porous. Permeate collects in the center of the laminate and drains into the header. 

Two-Dimensional Electrode Flow Cells. The simplest and least expensive cell design is the undivided parallel plate cell with electrolyte flow by some form of manifold. Electrical power is monopolar to the cell pack (72). An exploded view of the Foreman and Veatch cell is shown in Figure 7. Note that electrolyte flow is in series and that it is not easily adapted for divided cell operation. 

Section 10 of this Handbook describes the use of orifice meters for flow measurement. In addition, orifices are commonly found within pipelines as flow-restric ting devices, in perforated pipe distributing and return manifolds, and in perforated plates. Incompressible flow through an orifice in a pipehne as shown in Fig. 6-18, is commonly described by the following equation for flow rate Q in terms of pressure drop across the orifice Ap, the orifice area A, the pipe cross-sectional area A, and the density p. 

Description These exchangers are typically a series of stacked helical-coiled tubes connected to manifolds, then inserted into a casing or shell. They have many advantages hke spiral-plate designs, such as avoiding differential expansion problems, acceleration effects of the helical flow increasing the heat transfer coefficient, and compactness of plot area. They are typically selected because of their economical design. 

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