Drying solid products

Evaporation is the removal of a solvent by vaporisation, from solids that are not volatile. It is normally used to produce a concentrated liquid, often prior to crystallisation, but a dry solid product can be obtained with some specialised designs. The general subject of evaporation is covered in Volume 2, Chapter 14. That chapter includes a discussion of heat transfer in evaporators, multiple-effect evaporators, and a description of the principal types of equipment. The selection of the appropriate type of evaporator is discussed by Cole (1984). Evaporation is the subject of a book by Billet (1989). 

Macomber, R. S. et al., Synth. React. Inorg. Met.-Org. Chem., 1977, 7, 111-122 The dried solid product from interaction of lithium phenoxide and silver perchlorate in benzene (probably largely silver phenoxide) exploded on gentle heating. Other silver alkoxide derivatives were unstable. 

Place the dry solid product in a small beaker for further testing. 

Into a suitable flask equipped with motorized stirrer, thermometer and powder funnel, add 185 milliliters of 70% nitric acid, followed by carefully adding 350 milliliters of 98% sulfuric acid. Thereafter, place this flask into a water bath at room temperature, and then slowly add in small portions, 450 grams of dry powdered naphthalene over a period of 6 hours while rapidly stirring the acid mixture and maintaining its temperature below 30 Celsius. After the addition of the naphthalene, remove the powder funnel and replace it with a condenser and then reflux the entire reaction mixture for 2 hours at 60 Celsius with constant stirring. After refluxing for 2 hours, remove the heat source, and allow the reaction mixture to cool to room temperature. Thereafter, drown the entire reaction mixture into 1000 milliliters of ice water, and then filter-off the precipitated crystals. Then wash these crystals with three 250-milliliter portions of cold water, and then vacuum dry or air-dry the crystals. The dry solid product will be a mixture of para, ortho, and meta isomers. 

AH type dryer vMd for producing o dry, solid product from o wot food... 

Drying. Hot air is blown over wet solids—for example, over a wet cake deposited in a filter or centrifuge. The water evaporates, leaving a dry solid product. Drying is the last step in the production of most crystalline products and powders, including many pharmaceuticals and food products. 

Tankage comes from two sources the dried solid product of boiling the bones, skin, meat scraps, and other animal by-products from abattoirs and garbage treated with high-pressure steam and subsequently pressed. Both products are high in nitrogen, in the form of ammonia, and phosphorus as phosphoric acid, potash, and phosphates. Tankage can be flammable and presents a spontaneous combustion hazard. 

The most common acid solvent is inhibited muriatic acid. It is inhibited, as all acids solvents must be, to reduce chemical attack on metal surfaces to an acceptable level. Muriatic acid is cheap and effective. It forms reaction products that are generally water-soluble and so are removed in the used solvent. Sulfuric acid is seldom used because of its insoluble reaction products. Nitric acid cannot be prevented from attacking carbon steels or copper alloys. It has certain special applications where the substrate metal is stainless steel or aluminum. Of special interest for small-scale maintenance cleaning by plant personnel is sulfamic acid, mainly because it is a dry solid product that is safely to handle. It has acid properties only after it is dissolved in water. Solid inhibitors and wetting additives can be premixed into the packaged product. 

Piperazine hydrochloride is produced by conversion of piperazine hydrate with hydrochloric acid. The dry solid product is broken up, then milled and sieved. Piperazine products may be present in the air as vapours or as dust. 

The elemental composition of the raw peat and solid product was determined using an elemental analyzer (Yanaco CHN Corder MT-5 and MT-6). Additionally, proximate analysis (based on JIS M 8812) total sulfur analysis (based on JIS M 8819) and calorific analysis (based on JIS M 8814) were conducted separately. The gross calorific value (CV) was measured using the bomb calorimetric method and the effective calorific value (ECV) of the sample at a constant pressure was determined based on JIS M 8814, which is followed by ISO 1928. The equilibrium moisture content of the dried solid product was further analyzed while maintaining their moisture contents according to JIS M 8811. Briefly, an aliquot of the sample was placed inside a desiccator containing saturated salt solution and then measured rapidly using a moisture content analyzer (Sartorius MA 150). 

Decanter centrifuges, for process applications, are typically solid bowl scroll-discharge machines, capable of continuous sohd and centrate discharge. They are ideally suited to handling high feed solids concentrations and delivering dry solid products. They are generally able to convey the soft solids often encountered in the pharmaceutical and fermentation industries. 

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