Solid free-flowing

SOUND/epic (SOUND) owns the distribution rights in the United States to the dispersion by chemical reaction (DCR ) technology. The DCR process is a lime-based chemical stabilization process used to convert oily wastes into a solid, free-flowing, soil-like material. The technology has also been applied to soils contaminated with toxic heavy metals. SOUND has used the technology on full-scale remediation activities in the United States, and it is commercially available. 

Physical Form. For compounders, physical form is an important characteristic. They prefer solid, free-flowing, nondusty materials whereas polymer manufacturers prefer materials that are liquid and easily emulsified. Undesirable are semicrystalline materials which may stratify during storage. 

Feed rheology (solid) free flowing/friable/cohesive/sticky/paste/. 

Vacuum Shelf Dryer. It is the simplest and oldest vacuum dryer known. It can be used for drying a wide range of materials like solids, free flowing powders, fibrous solids having special forms and shape, practically any material that can be contained in a tray. It finds application where the material is sensitive to heat and so valuable that labor costs are insignificant. At the same time, it is normally used when the powder production is very low. 

Liquids Slurries Pastes and sludges Free-flowing powders Granular, crystalbne, or fibrous solids Large sobds, special forms and shapes Continuous sheets Discontinuous sheets... 

Vibrating-conveyor dryers are suitable for free-flowing solids containing mainly surface moisture. Retention is limited by conveying speeds which range from 0.02 to 0.12 m/s. Bed depth rarely exceeds 7 cm, although units are fabricated to carry 30- to 46-cm-deep beds these also employ plate and pipe coils suspended in the bed to provide additional heat-transfer area. Vibrating dryers are not suit le for fibrous materials which mat or for sticky sohds which may ball or adhere to the deck. 

When the solid is one of the reactants, such as in ore roasting, the flow must be continuous and precise in order to maintain constant conditions in the reactor. Feeding of free-flowing granular solids into a fluidized bed is not difficult. Standard commercially available sohds-weighiug and -conveying equipment can be used to control the rate and dehver the solids to the feeder. Screw conveyors, dip pipes, seal legs, and injectors are used to introduce the solids into the reactor... 

FIG. 21-28 Sloping striker plate in the belt of an apron feeder ensures the flow of non-free-flowing solids, Couitesif of Chemical Engineering,)... 

Sodium fluoroacetate (mono) [62-74-8] M 100.0, m 200-205 (dec). A free flowing white TOXIC powder which is purified by dissolving in ca 4 parts of H2O and the pH is checked. If it is alkaline, add a few drops of FCH2CO2H to make the solution just acidic. Evaporate (fumehood) on a steam bath until crystals start to separate, cool and filter the solid off. More solid can be obtained by adding EtOH to the filtrate. Dry at 100 in vacuum. [7 Chem Soc 1778 1948.]... 

Either straightforward drainage or blowdown can readily remove sludge from the plant. It is, however, necessary in some cases to ensure that the residual solids are free-flowing this is achieved by the use of tannin, lignin, seaweed derivatives, and starch organics. 

Preparation of Intermediate Compound 2-Methyl-3-o-Tolyl-6-Sulfamyl-7-Chloro-4(3H)-Quinazoiinone Set up a 5-liter 3-necked flask fitted with a stirrer, condenser and a drying tube. To a stirred mixture of 100 g (0.342 mol) of powdered 4-chloro-5-sulfamyl-N-acetylanthranilic acid, 40.2 g (0.376 mol) of o-toluidine and 2.0 liters of dry toluene was added dropwise, over a period of 15 minutes, 21.7 ml (34.1 g) (0.248 mol) of phosphorus trichloride. The mixture was then refluxed for 10 hours. The solid turned somewhat gummy towards the latter part of the first hour. The mixture then became more free flowing as heating was continued. Let stand overnight. The yellow solid was filtered, washed with toluene and dried. The toluene filtrate was discarded. The dried solid was triturated with 1.5 liters of 10% sodium bicarbonate, filtered and the cake washed with water. The filtrate on acidification yielded 11.5 g of the starting acid. The damp product was dissolved in 4,5 liters of 95% ethanol and the solution treated with charcoal and filtered. On cooling filtrate yielded 69.5 g (55.5%) of the title compound, MP 271.5° to 274°C. 

Powder products formulated with too much hydroxide can be hygroscopic and thus tend to go solid in storage rather than remaining as free-flowing powders. 

Conduction. In a solid, the flow of heat by conduction is the result of the transfer of vibrational energy from one molecule to another, and in fluids it occurs in addition as a result of the transfer of kinetic energy. Heat transfer by conduction may also arise from the movement of free electrons, a process which is particularly important with metals and accounts for their high thermal conductivities. 

CONFINED SPACE A spacc which is substantially, although not always entirely, enclosed and where there is a reasonably foreseeable risk of serious injury from hazardous substances or conditions within the space or nearby. The risks may include flammable substances oxygen deficiency or enrichment toxic gases, fume or vapour ingress or presence of liquids free-flowing solids presence of excessive heat. For the purpose of the Confined Spaces Regulations 1997 a confined space means any place, including any chamber, tank, vat, silo, pit, trench, pipe, sewer, flue, well or other similar space in which, by virtue of its enclosed nature, there arises a reasonably foreseeable specified risk. 

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