Low-level process

Is low level process heat used to preheat deaerator makeup ... 

L. J. King, Pilot Plant Studies of the Decontamination of Low Level Process Waste by a Scavenging Precipitation Foam Separation Process, U.S. Atomic Energy Commission, ORNL-3808, 57 pages, 1968. 

Removal of Plutonium from Low-Level Process Wastewaters by Adsorption... 

It must possess low level processes which act on the Cartesian coordinates to diagnose molecular features such as chains and rings. 

Adequate low-level process energy is available for a bottoming cogeneration system. 

Ambient-Temperature Removal. The vast majority of acid gas removal processes operate at high ambient temperatures (90-120°F). These systems are almost as efficient as cold systems, but have lower capital cost and are much simpler. These processes can reduce H2S to about 10-50 ppmv. The key operating cost is the large heat requirement for stripping. This cost is minor in most coal gasification plants because of the ample supplies of low-pressure steam and low-level process heat in the plants. Commonly used acid gas removal processes at these conditions include MDEA (methyldiethanolamines) and Sulfinol. 

Purity Highly homogeneous (well defined) Low-level process and product-related impurities... 

The properties required by jet engines are linked to the combustion process particular to aviation engines. They must have an excellent cold behavior down to -50°C, a chemical composition which results in a low radiation flame that avoids carbon deposition on the walls, a low level of contaminants such as sediment, water and gums, in order to avoid problems during the airport storage and handling phase. 

The vacancy is very mobile in many semiconductors. In Si, its activation energy for diffusion ranges from 0.18 to 0.45 eV depending on its charge state, that is, on the position of the Fenni level. Wlrile the equilibrium concentration of vacancies is rather low, many processing steps inject vacancies into the bulk ion implantation, electron irradiation, etching, the deposition of some thin films on the surface, such as Al contacts or nitride layers etc. Such non-equilibrium situations can greatly affect the mobility of impurities as vacancies flood the sample and trap interstitials. 

Vitamin D3 is a key compound m the process by which Ca " is absorbed from the mtes tine Low levels of vitamin D3 lead to Ca " concentrations m the body that are msuffi cient to support proper bone growth resulting m the bone disease called rickets... 

Process Concepts. Hybrid systems involving gas-phase adsorption coupled with catalytic processes and with other separations processes (especially distillation and membrane systems) will be developed to take advantage of the unique features of each. The roles of adsorption systems will be to efficiently achieve very high degrees of purification to lower fouUng contaminant concentrations to very low levels in front of membrane and other separations processes or to provide unique separations of azeotropes, close-boiling isomers, and temperature-sensitive or reactive compounds. 

Greater dimensional control and thinner tapes in multilayer ceramics are the driving forces for techniques to prepare finer particles. Metal organic decomposition and hydrothermal processing are two synthesis methods that have the potential to produce submicrometer powders having low levels of agglomeration to meet the demand for more precise tape fabrication. 

Aqueous media, such as emulsion, suspension, and dispersion polymerization, are by far the most widely used in the acryUc fiber industry. Water acts as a convenient heat-transfer and cooling medium and the polymer is easily recovered by filtration or centrifugation. Fiber producers that use aqueous solutions of thiocyanate or zinc chloride as the solvent for the polymer have an additional benefit. In such cases the reaction medium can be converted directiy to dope to save the costs of polymer recovery. Aqueous emulsions are less common. This type of process is used primarily for modacryUc compositions, such as Dynel. Even in such processes the emulsifier is used at very low levels, giving a polymerization medium with characteristics of both a suspension and a tme emulsion. 

The separation of nitrogen from natural gas reHes on the differences between the boiling points of nitrogen (77.4 K) and methane (91.7 K) and involves the cryogenic distillation of a feed stream that has been preconditioned to very low levels of carbon dioxide, water vapor, and other constituents that would form soHds at the low processing temperatures. 

The various lubricants formulated into PVC to improve the processing can also enhance the performance of the stabilizet. In pigmented apphcations, calcium soaps, eg, calcium stearate, ate commonly used as internal lubricants to promote PVC fusion and reduce melt viscosity. This additive is also a powerfiil costabilizer for the alkyl tin mercaptide stabilizers at use levels of 0.2 to 0.7 phr. Calcium stearate can significantly improve the eady color and increase the long-term stabiUty at low levels however, as the concentration increases, significant yellowing begins to occur. 

Oxides of nitrogen, NO, can also form. These are generally at low levels and too low an oxidation state to consider water scmbbing. A basic reagent picks up the NO2, but not the lower oxidation states the principal oxide is usually NO, not NO2. Generally, control of NO is achieved by control of the combustion process to minimize NO, ie, avoidance of high temperatures in combination with high oxidant concentrations, and if abatement is required, various approaches specific to NO have been employed. Examples are NH injection and catalytic abatement (43). 

---