Controlled release feed additives

Amine-containing cellulose esters, eg, the acetate A/A/-diethylaminoacetate (36) and propionate morpholinobutyrate (35), are of interest because of their unique solubiHty in dilute acid. Such esters are prepared by the addition of the appropriate amine to the cellulose acrylate crotonate esters or by replacement of the chlorine on cellulose acrylate chloroacetate esters with amines. This type of ester has been suggested for use in controlled release, mmen-protected feed supplements for mminants (36,37). 

The semi-batch process is similar to the batch process except feed addition occurs during the batch cycle. Products may also be removed during the semi-batch process. The addition/removal policy allows one to control the reaction rate or heat release during reaction. The semi-batch reactor also may provide more complete... 

Sulfonamides are administered to food-producing species as additives to feed and drinking water, controlled-release oral boluses, and intrauterine infusions. These drugs are applied to the brood chambers of honeybee hives mixed with confectioners sugar or in syrup. The insoluble nature of sulfonamides is an important consideration. Highly insoluble sulfonamides such as phthalylsulfathiazole are absorbed from the gastrointestinal tract very slowly and are used to treat enteric infections. With triple sulfas for oral administration, the concentration of individual sulfonamides is limited by the drug s solubility, while efficacy reflects the additive activity of all three components. Sodium salts of sulfonamides, which are readily soluble in water, are available for intravenous administration. 

Chem. Descrip. Complexed lecithin CAS 8002-43-5 EINECS/ELINCS 232-307-2 Uses Instantizer, spray oils, mold release for foods food emulsifier for w/ 0 emulsions concrete (powder dispersant) dust control latex paints coatings/adhesives feed additives leather tanning lubricants mold release agents pesticides/herbicides corrosion/rust inhibitors putty/ caulking compds. emulsifier for w/o emulsions Properties Translucent fluid vise. 10 stokes HLB 2.0 acid no. 25 max. Beakin LV3P [ADM Lecithin]... 

Chem. Descrip. Complexed lecithin CAS 8002-43-5 EINECS/ELINCS 232-307-2 Uses Concrete (powder dispersant) dust control latex paints coatings/ adhesives feed additives leather tanning lubricants mold release... 

Humidification. For wiater operation, or for special process requirements, humidification maybe required (see Simultaneous HEAT and mass transfer). Humidification can be effected by an air washer which employs direct water sprays (see Evaporation). Regulation is maintained by cycling the water sprays or by temperature control of the air or water. Where a large humidification capacity is required, an ejector which direcdy mixes air and water in a no22le may be employed. Steam may be used to power the no22le. Live low pressure steam can also be released directly into the air stream. Capillary-type humidifiers employ wetted porous media to provide extended air and water contact. Pan-type humidifiers are employed where the required capacity is small. A water filled pan is located on one side of the air duct. The water is heated electrically or by steam. The use of steam, however, necessitates additional boiler feed water treatment and may add odors to the air stream. Direct use of steam for humidification also requires careful attention to indoor air quahty. 

This is the most common mode of addition. For safety or selectivity critical reactions, it is important to guarantee the feed rate by a control system. Here instruments such as orifice, volumetric pumps, control valves, and more sophisticated systems based on weight (of the reactor and/or of the feed tank) are commonly used. The feed rate is an essential parameter in the design of a semi-batch reactor. It may affect the chemical selectivity, and certainly affects the temperature control, the safety, and of course the economy of the process. The effect of feed rate on heat release rate and accumulation is shown in the example of an irreversible second-order reaction in Figure 7.8. The measurements made in a reaction calorimeter show the effect of three different feed rates on the heat release rate and on the accumulation of non-converted reactant computed on the basis of the thermal conversion. For such a case, the feed rate may be adapted to both safety constraints the maximum heat release rate must be lower than the cooling capacity of the industrial reactor and the maximum accumulation should remain below the maximum allowed accumulation with respect to MTSR. Thus, reaction calorimetry is a powerful tool for optimizing the feed rate for scale-up purposes [3, 11]. 

Calorimetric measurements show that the addition is exothermic [34], The heat release rate is mainly feed controlled, as the square shape of the heat flow curve demonstrates (see Figure 5.5). Whenever feed is added, the heat flow responds without delay. 

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