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System operator

Adsorption. Some organics are not removed in biological systems operating under normal conditions. Removal of residual organics can be achieved by adsorption. Both activated carbon and synthetic resins are used. As described earlier under pretreatment methods, regeneration of the activated carbon in a furnace can cause carbon losses of perhaps 5 to 10 percent. [Pg.319]

Breakdown and subsequent repair is clearly non-scheduled, but gives rise to nonavailability of the item. Some non-critical items may actually be maintained on a breakdown basis, as discussed in Section 11.3. Flowever, an item which is critical to keeping the production system operating will be designed and maintained to make the probability of breakdown very small, or may be backed up by a stand-by unit. [Pg.343]

Some preliminary tests were performed to set up the experimental apparatus, to check the sensors (pressure and strain gauges) and the SPATE system operation. [Pg.410]

Over the period of service the P-scan unit has proved to be a reliable system, operating in a stable manner under the conditions of strong electrical interference, natural atmospheric precipitation. The mechanical scanner of the system adapts quite... [Pg.790]

These chemical effects become important in medicine because living systems operate mostly through the reactions of enzymes, which catalyze all sorts of metabolic reactions but are very sensitive to small changes in their environment. Such sensitivity can lead to preferential absorption of some deleterious isotopes in place of the more normal, beneficial ones. One example in metabolic systems can be found in the incorporation of a radioactive strontium isotope in place of calcium. [Pg.364]

The technology involved makes recirculating systems expensive to constmct and operate. Redundancy in the system, ie, providing backups for all critical components, and automation are important considerations. When a pump fails, for example, the failure must be instantly communicated to the culturist and the culturist must have the abiUty to keep the system operating while the problem is being addressed. Loss of a critical component for even a few minutes can result in the loss of all animals within the system. [Pg.19]

Voltages given are for a De Nora 24M2 system operating at 10 kA/m (270 kA). [Pg.484]

The pressure-volume curve of a proposed centrifugal fan has a different shape. This fan curve must be drawn for the anticipated fan inlet density expected at its location in the system. The point of intersection of these two curves locates the flow rate and pressure rise at which the fan and system operate. This intersection represents a desirable operating combination for fan and system. The system curve intersects the fan curve in the middle of its maximum efficiency range and also at a point where the fan pressure produced varies smoothly but distinctly in a constant trend with flow rate which is desirable for flow control. [Pg.106]

Sasol produces synthetic fuels and chemicals from coal-derived synthesis gas. Two significant variations of this technology have been commercialized, and new process variations are continually under development. Sasol One used both the fixed-bed (Arge) process, operated at about 240°C, as weU as a circulating fluidized-bed (Synthol) system operating at 340°C. Each ET reactor type has a characteristic product distribution that includes coproducts isolated for use in the chemical industry. Paraffin wax is one of the principal coproducts of the low temperature Arge process. Alcohols, ketones, and lower paraffins are among the valuable coproducts obtained from the Synthol process. [Pg.164]

The best fibers, installed in systems operating at 0.9 )J.m, had losses of 5 dB/km. The lower intrinsic losses in the 1.3 to 1.55-)J.m window were unattainable by this technique. Fundamental cation—oxygen vibrational modes as well as OH contamination were intrinsic to the compositions. [Pg.253]

Either mechanism can be used to describe how antimony—halogen systems operate in both the condensed and vapor phases. In the condensed phase a chat that is formed during the reaction of the polymer, antimony trioxide, and the halogen reduces the rate of decomposition of the polymer therefore, less fuel is available for the flame (16). [Pg.456]

Suspension polymerization of VDE in water are batch processes in autoclaves designed to limit scale formation (91). Most systems operate from 30 to 100°C and are initiated with monomer-soluble organic free-radical initiators such as diisopropyl peroxydicarbonate (92—96), tert-huty peroxypivalate (97), or / fZ-amyl peroxypivalate (98). Usually water-soluble polymers, eg, cellulose derivatives or poly(vinyl alcohol), are used as suspending agents to reduce coalescence of polymer particles. Organic solvents that may act as a reaction accelerator or chain-transfer agent are often employed. The reactor product is a slurry of suspended polymer particles, usually spheres of 30—100 pm in diameter they are separated from the water phase thoroughly washed and dried. Size and internal stmcture of beads, ie, porosity, and dispersant residues affect how the resin performs in appHcations. [Pg.386]

Gas-Cycle Systems. In principle, any permanent gas can be used for the closed gas-cycle refrigeration system however, the prevailing gas that is used is air. In the gas-cycle system operating on the Brayton cycle, all of the heat-transfer operations involve only sensible heat of the gas. Efficiencies are low because of the large volume of gas that must be handled for a relatively small refrigera tion effect. The advantage of air is that it is safe and inexpensive. [Pg.508]

Ammonia—water systems operate under moderate pressures and care must be taken to avoid leaks of the irritating and toxic ammonia (qv). Sometimes a third material with a widely different density, eg, hydrogen, is added to the cycle in order to eliminate the need for mechanical pumping. [Pg.508]

Wetox uses a single-reactor vessel that is baffled to simulate multiple stages. The design allows for higher destmction efficiency at lower power input and reduced temperature. Its commercial use has been limited to one faciHty in Canada for treatment of a complex industrial waste stream. Kenox Corp. (North York, Ontario, Canada) has developed a wet oxidation reactor design (28). The system operates at 4.1—4.7 MPa (600 to 680 psi) with air, using a static mixer to achieve good dispersion of Hquid and air bubbles. [Pg.502]

DeioniZa.tlon, The removal of cations and anions from water and replacement of them with hydrogen and hydroxide ions is called deionization. The completeness of the ionic removal is dependent on resin selection, design of the system, operating conditions, and the quaUty of treated water required. In general, systems become more complex as quaUty requirements increase. [Pg.386]

The transducers on most ultrasound imaging systems operate at a frequency between 1 and 20 MH2. The attenuation, of ultrasound by tissues is both frequency and tissue dependent. The attenuation coefficient, a, of a tissue is defined by equation 5 ... [Pg.53]

Some inorganic nonaqueous solvents can be used in systems operable at near room temperature, eg, thionyl chloride others, however, require special handling, eg, Hquid ammonia, which must be used below its boiling point of —33° C in a thermally insulated container and in an inert atmosphere. [Pg.133]

GeneraHy the systems operate in the gas phase, but a system in which the superoxides react with Hquid-phase water and absorb CO2 in the resultant KOH solution has been buHt (25). The RQ is fixed at 0.67. [Pg.487]

Chromyl perchlorate has been suggested for a gas-generating system operating at —45° C (66). [Pg.67]

For piping systems operating within at least 150°C above or below ambient temperature, heat loss or gain, respectively, from the piping to the support system should be evaluated, as well as local thermal stresses due to temperature differences between the pipe and its support attachment. Clamp-type supports iasulated from the piping, and extended support connections with the support members covered with iasulation at the support junction and for a distance beyond frequently are used for such systems. [Pg.61]

The melt flows from the extmder iato the die where it flows around the bend and around the core tube. On the far side of the core tube, it forms a weld. Melt sticks to and is pulled by the moving wire. Details of the sizes and shapes of the die parts ia contact with the melt are important ia obtaining a smooth coating at high rates. The die exit usually is the same diameter as that of the coated wire and there is Httle drawdown. Die openings are small and pressures iaside the die are high at ca 35 MPa (5000 psi). Wire takeup systems operate as high as 2000 m /min. [Pg.141]

J. W. MausteUer, E. Tepper, and S. J. Rodgers, FUkali Metal Handling and Systems Operating Techniques, Gordon and Breach Scientific PubUshers, Inc., New York, 1967. [Pg.520]


See other pages where System operator is mentioned: [Pg.414]    [Pg.469]    [Pg.571]    [Pg.703]    [Pg.789]    [Pg.2821]    [Pg.2822]    [Pg.200]    [Pg.206]    [Pg.510]    [Pg.90]    [Pg.56]    [Pg.504]    [Pg.16]    [Pg.424]    [Pg.475]    [Pg.476]    [Pg.16]    [Pg.135]    [Pg.402]    [Pg.428]    [Pg.436]    [Pg.444]    [Pg.222]    [Pg.343]    [Pg.76]    [Pg.76]    [Pg.97]   
See also in sourсe #XX -- [ Pg.37 ]

See also in sourсe #XX -- [ Pg.135 ]

See also in sourсe #XX -- [ Pg.109 , Pg.111 ]




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