Hard panned products

Site 2 is situated on the south shore of Moore s pit (Figs. 1 2b). This site consists of i) a pyritic waste rock pile, covered with a thin veneer of Fe-oxide tailings and ii) a down stream acid drainage affected area that is characterized by a Fe oxide + sulfur-rich hard pan surface layer that overlies a stratified unit comprised of intensely altered (Fe-oxide stained) and unaltered Quaternary glaciolacustrine deposits. A small creek (product of beaver activities) flows along the eastern margin of the site into Moore s pond. 

Soils of the humid region and Temperate Zone that were at one time productive often become comparatively nonproductive after several years of cropping if little attention is given to maintenance of soil fertility. Among the chief reasons for the decrease in yields are decrease in available nutrients increase in acidity lack of adequate organic matter poor physical condition build up of toxic substances plant diseases insects and weed competition. There are other possibilities, some of which are closely related to the above, namely inadequate aeration, hard pans, slow infiltration, and poor drainage. 

Sodium alum occurs naturally as the mineral mendo2ite. Commercially, it is produced by the addition of a sodium sulfate solution to aluminum sulfate. Small amounts of potassium sulfate, sodium siUcate, and soda ash can be added to improve product handling and performance. After adjustment of the ratio of aluminum sulfate to sodium sulfate, water is evaporated to give a hard cake ia the cooling pans. This cake is further heated ia roasters and ground to a fineness of 99% through a 100-mesh (- 150 fiva) sieve. 

Many sweets (confections) must be colored, a strong point in their attractiveness for consiuners. The commonly colored products are candies (starch jellies, candy cream centers, pan-coated candies, and hard candies), tablets, wafers, oil-based coatings, and chewing gmns. 

The raw material should contain at least 50 per cent, of Ca3P208 and be as free as possible from sesquioxides. It may be ignited if high in organic matter, reduced to a fine powder, and fed continuously into tanks lined with wood or hard lead alloy, where it meets on the counter current principle hot sulphuric acid of about 5 per cent, concentration. The reaction is quickly completed and the precipitated calcium sulphate is allowed to settle and filtered off continuously through filter presses. This sulphate is phosphatic gypsum and contains 3 to 4 per cent, of phosphoric acid of which 1 per cent, is soluble in water. The solution is evaporated in wrought-iron pans up to a concentration of 50 per cent, phosphoric acid, which may be further refined for use in pharmaceutical products or foods. 

Pan and drum coating spherical substrate/quite resistant, hard shelf on soft product (sugars coatings on jelly beans/candied fruit), batch process, heat balance control, adhesion, avoid cluster formation... 

Performance The dry pan is useful for crushing medium-hard and soft materials such as clays, shales, cinders, and soft minerals such as barites. Materials fed should normally be 7.5 cm (3 in) or smaller, and a product able to pass No. 4 to No. 16 sieves can be dehvered, depending on the hardness of the material. 

A very important catalytic process is hydrogenation of fats, fatty acids, and vegetable oils used in foodstuffs. Reduced nickel catalysts are used for this purpose. They usually contain about 60% Ni on a support and are suspended in a protective hard fat, such as saturated glyceride, tallow, or vegetable oil. The particles are flake or drop-like and are used in liquid phase hydrogenation after the protective fat dissolves in the reagent. Since the fat becomes pan of the product, catalysts used in food production must conform to health and religious standards. 

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