Feed conveying

Zufuhr,/. addition supply, supplies (Tech.) feed conveyance importation administration (of medicines). 

A machine that accepts solid (pellets or powder) or liquid feed, conveys it through a surrounding barrel by means of a rotating screw(s), and pumps it, under pressure, through an orifice called die. ... 

There have been many innovations patented in the design of extruders and extrusion components to improve uneven feeding, conveying, mixing, and temperature control. For example, a new type of compounding extruder (ESK Series) has been patent by Werner Pfleiderer Corporation which consists of both twin-screw and single-screw sections (see Fig. 2-46). 

Powder feeding, Conveying and Gravimetric dosing station... 

The carbamate solution from the scmbber flows to a high pressure ejector. The NH feed pressure induces enough head to convey the carbamate solution from the scmbber to the carbamate condenser. 

Fig. 2. Internieshing co-iotating twin-sciew extrudei A, motoi B, geai box C, feed poit D, clam shell baiiel E, vent poit F, sciew shafts G, conveying screws H, kneading paddles 1, baiiel valve and J, bhstei rings. Courtesy of APV Chemical Machinery Inc.

Fig. 10. Mass flow screw feeder designs, (a) Combined tapered shaft and variable pitch screw feeder where A represents a conical shaft and constant pitch (feed section) B, constant shaft and increasing pitch (feed section) and C, constant shaft and constant pitch (conveying section), (b) Stepped shaft screw feeder where A represents a stepped diameter shaft and constant pitch (feed section) and B, constant shaft and constant pitch (conveying section).

A distinct concern arises in the area of veterinary dmgs because of the possibiUty that dmg residues may be conveyed to humans by the food-producing animals. Therefore, dmg residues and their safety in human food remain a central issue for the Center for Veterinary Medicine (CVM). Animal dmgs also include those products which promotional Hterature claims to improve feed efficiency and increase milk production. An animal food product is regulated under the 1968 Animal Dmg Amendments if it contains a dmg used in feed or premixes (25). 

Suspended Particle Techniques. In these methods of size enlargement, granular soHds are produced direcdy from a Hquid or semiliquid phase by dispersion in a gas to allow solidification through heat and/or mass transfer. The feed Hquid, which may be a solution, gel, paste, emulsion, slurry, or melt, must be pumpable and dispersible. Equipment used includes spray dryers, prilling towers, spouted and fluidized beds, and pneumatic conveying dryers, all of which are amenable to continuous, automated, large-scale operation. Because attrition and fines carryover are common problems with this technique, provision must be made for recovery and recycling. 

The oxide exiting either the Barton or ball mill reactor is conveyed by an air stream to separating equipment, ie, settling tank, cyclone, and baghouse, after which it is stored in large hoppers or dmmmed for use in paste mixing. Purity of the lead feed stock is extremely critical because minute quantities of some impurities can either accelerate or slow the oxidation reaction markedly. Detailed discussions of the oxide-making process and product are contained in references 55—57. 

For a coarse-grained (particle containing) graphite, the system depicted in Figure 1 is typical. The nin-of-kiln coke is brought in on railroad cars and emptied into pits where the coke is conveyed to an elevator. The elevator feeds a second conveyor that empties the coke into any one of a number of storage silos where the coke is kept dry. The manufacturer usually specifies a maximum moisture content in the incoming coke at about 0.1—0.2% to ensure that mix compositions are not altered by fluctuations in moisture content. 

Dried coal is pneumatically conveyed to feed bins, pressurized through lockhoppers, and fed to the refractory-lined fluidized-bed gasifier vessel by variable-speed screws. The gasifying agent, mixed oxygen and steam, is fed near the bottom of the gasifier. The bed operates at 2.5 MPa (25 bar) and... 

Dense phase systems are at cost disadvantage when multiple feed points are required, or when incremental compressed air for conveying is not available from existing sources. In the latter instance, the entire investment cost of an air compressor and associated auxiUaries must be allocated to the cost of the conveying system. 

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