Flashing melt-processible

The high-grade matte from the converter process or the flash melting process contains sulfur and some amounts of copper, cobalt and iron and, in addition, traces of noble metals. Refined nickel is produced by a variety of methods and is delivered as nickel cathodes or nickel powder. The latter are produced partly by carbonyl processes, partly by hydrogen reduction in conjunction with pressure leaching processes. In the latter, matte is leached under pressure with acid or ammonia, and nickel is recovered as a powder by reduction with hydrogen under pressure. 

Low-temperature exchange (LTX) units use the high flowing temperature of the well stream to melt the hydrates after they are formed. Since they operate at low temperatures, they also stabilize the condensate and recover more of the intermediate hydrocarbon components than would be recovered in a straight multistage flash separation process. 

Perhaps the best current way to view the disk of debris from which the Earth accreted was as an environment of vigorous mixing. Volatile-depleted material that had witnessed very high temperatures at an early stage (CAIs) mixed with material that had been flash melted (chondrules) a few milhon years later. Then presolar grains that had escaped these processes rained into the... 

A further important and yet incompletely resolved matter is the nature of the heating event in which chondrules formed. The experimental study of Cohen et al. (2004) shows that chondrules probably formed in a matter of minutes to hours. This implies a flash heating process (Boss, 1998), such as might be caused by shock-heating or lightning strikes in the solar nebula. If this is the case then chondrule melting temperatures represent transient temperatures rather than the ambient temperature of the solar nebula. 

Different types of machine process controls (PCs) can be used to meet different requirements based on the molder s needs. PC systems range from the unsophisticated monitors (alami buzzes, light flash) to very sophisticated program controllers (personal computers (PCs) interrelate different IMM functions and melt process variables) (Figure 30). (Note that PC has different definitions see Appendix A, List of Abbreviations.)... 

Spun bonded media production processes exploit the thermosetting properties of polymers, to form fibres that can be bonded by combinations of heat, pressure and chemical activation. Melt spinning, using conventional synthetic fibre technology, was the earliest method used for producing spun bonded filter media and continues to be of major importance, but finer fibres are produced by melt blowing and flash spinning processes. 

Uses Surfactant intermediate, engine oil lubricant additive, viscosity and pour-point improver, plasticizer, epoxy, antifreeze lubricant, control for leather goods and corrosion inhibitor sizing agent in the alkaline production of paper Features Good thermal stability melt processable cost effective Properties Cl, amber liq, sp, gr, 0,955 vise, 250 cs b.p. 235 5 mm Hg flash pt. (PM-CC)195C... 

Reduction to Liquid Metal. Reduction to Hquid metal is the most common metal reduction process. It is preferred for metals of moderate melting point and low vapor pressure. Because most metallic compounds are fairly insoluble in molten metals, the separation of the Hquified metal from a sohd residue or from another Hquid phase of different density is usually complete and relatively simple. Because the product is in condensed form, the throughput per unit volume of reactor is high, and the number and si2e of the units is rninimi2ed. The common furnaces for production of Hquid metals are the blast furnace, the reverberatory furnace, the converter, the flash smelting furnace, and the electric-arc furnace (see Furnaces, electric). 

However, some semiaromatic nylons can give problems as a result of the high melt viscosity. A process for produciag polymers of hexamethylenediamine, adipic acid, terephthaUc acid, and isophthaUc acid has been developed, which iavolves vaporising the salt mixture ia a high temperature flash reactor followed by molecular weight iacrease ia a twia-screw extmder with efficient moisture removal (17). 

Alternatives to the fluidized-bed method process include the chlorination of titanium slags in chloride melts, chlorination with hydrogen chloride, and flash chlorination. The last is claimed to be particularly advantageous for minerals having a high impurity content (133—135,140). The option of chlorinating titanium carbide has also been considered (30). 

Processing PC resins by extmsion or injection-molding methods requires melt temperatures of 290—320°C. High melt viscosity at low shear rates prevents mold flash and drool. At injection shear rates, apparent viscosities decrease, and easy melt flow allows manufacture of large, complex parts. 

In summary, a colder separation temperature removes more liquid from the gas stream adequate bottom heating melts the hydrates and revaporizes the lighter components so they may rejoin the sales gas instead of remaining in liquid form to be flashed off at lower pressure and cold refluxing recondenscs the heavy components that may also have been vaporized in the warming process and prevents their loss to the gas stream. 

The FSD is a flash evaporator, whereby the preheated polymer solution/melt falls within the vessel primarily by gravity, while the volatiles evaporate during falling. This method is normally used with process streams that are not exceptionally temperature-sensitive and where the concentration of volatiles is relatively high. 

Chondrules comprise the major portion of most chondrites, the most abundant type of meteorites. If the achondrites and terrestrial planets formed from chondrite-like precursors, then much, perhaps most of the solid matter in the inner solar system once existed as chondrules. Even if chondrules were restricted to the chondrites, the process that formed them was important in that region. The origin of chondrules is an important unsolved problem in cosmochemistry. Chondrules formed in the Sun s accretion disk through some sort of transient flash-heating event(s). Some CAIs apparently also were melted in the disk. What was the process (or processes) that melted the chondrules and CAIs Whatever it was, it dominated the disk for at least a few million years. 

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