Copper porcelain enameling

Wastewater from the Porcelain Enameling on Copper Subcategory. 312... 

The porcelain enameling industry consists of at least 116 plants enameling approximately 150 million square meters (150 km2) of steel, iron, aluminum, and copper each year (each coat of multiple coats is considered in this total). Porcelain enameling is the application of glass-like coatings to the metals mentioned above. The purpose of the coating is to improve resistance to chemicals, abrasion, and water, and to improve thermal stability, electrical resistance, and appearance. The coating... 

In general, only 10% of the porcelain enameling facilities enamel more than one type of base metal. Over 70% of the plants enamel solely on steel, 10% on aluminum, and 8% on iron. Less than 1% of the plants enamel copper, strip steel, or strip aluminum separately.3-6... 

Porcelain enameling on copper represents a very small part of the porcelain enameling category. It is not practiced by many firms and the ones involved do it on a small scale. Enameled copper is used mostly for ornamental purposes, such as jewelry, decorative ware, and metal sculpture. The average yearly production of a plant in this subcategory is 1.4 x 104 m2 (1.5 x 104 ft2). 

The introduction of enamel into the wastestream results in an increase in the concentration of metals, but these metals (antimony, titanium, zirconium, tin, cobalt, and manganese) are in solid form whereas the metals generated by surface preparation are normally in dissolved form. These solid metals increase the suspended solids concentration of the stream. Other metals that may be found in the enamel preparation and application wastestream in significant amounts include aluminum, copper, iron, lead, nickel, and zinc. Table 8.2 presents pollutant sampling data for the processes used in the porcelain enameling on steel industry. 

Table 8.13 gives the water use for each process in the production of porcelain enameled copper for two plants. Pollutant concentrations in the treated effluent are given in Table 8.14. 

Chemical precipitation is used in porcelain enameling to precipitate dissolved metals and phosphates. Chemical precipitation can be utilized to permit removal of metal ions such as iron, lead, tin, copper, zinc, cadmium, aluminum, mercury, manganese, cobalt, antimony, arsenic, beryllium, molybdenum, and trivalent chromium. Removal efficiency can approach 100% for the reduction of heavy metal ions. Porcelain enameling plants commonly use lime, caustic, and carbonate for chemical precipitation and pH adjustment. Coagulants used in the industry include alum, ferric chloride, ferric sulfate, and polymers.10-12... 

Zinc oxide is a very old technological material. Already in the Bronze Age it was produced as a byproduct of copper ore smelting and used for healing of wounds. Early in history it was also used for the production of brass (Cu-Zn alloy). This was the major application of ZnO for many centuries before metallic zinc replaced the oxide [149]. With the start of the industrial age in the middle of the nineteenth century, ZnO was used in white paints (chinese white), in rubber for the activation of the vulcanization process and in porcelain enamels. In the following a number of existing and emerging electronic applications of ZnO are briefly described. 

For the larger operations of the chemist or pharmaceutist, vessels of copper, tin, enamelled iron, tinned copper, and for some puiposes very large porcelain capsules are more suitable. 

Boric acid is used to make heat-resistant glass. It is used in porcelain enamels and glass fibers. Boric acid is also used in metallurgy, in welding flux, and in copper brazing, in addition, boric acid is used in flame-retarding textile products. 

Colored glazes are made with the addition of nearly pure oxides of manganese, copper, iron, chromium, cobalt, et cetera ) opaque glasses, ot enamels, by the addition of oxide of tin, or phosphate of lime for which see Porcelain True and Earthenware, Some of the ordinary lead glazes for soft porcelain are given below —... 

Pme oil -m disinfectants (DISINFECTANTS AND ANTISEPTICS] (Vol 8) -for enamel decorating pNAMELS, PORCELAIN OR VITREOUS] (Vol 9) -sampling standards for [SAMPLING] (Vol 21) -use m copper refining [COPPER] (Vol 7)... 

The reaction vessel must be metal. Only wrought iron is used industrially, but in the laboratory copper vessels can be used to advantage. Glass, porcelain, and enameled vessels are not usable. However, if it is desired to use such vessels in the laboratory, a small quantity of a soluble copper salt must be added. Then metallic copper deposits on the surface of the iron and this appreciably increases the reactivity of the iron. 

Throughout recorded history, copper(II) oxide has been used as a pigment to color ceramics, enamels, porcelain... 

Uses Flame retardant for textiles, paper, plastics, PVC, rubber, cellulosics, paint white pigment for paints and plastics opacifier for ceramics, glass, porcelain, glazes staining iron and copper phosphorus mordant glass decolorization catalyst intermediate filler for thermoplastic and thermoset plastics, rubbers, coatings in enamels glasses mfg. of tartar emetic in food-pkg. adhesives... 

Anhydrous phosgene in the liquid state is compatible with a variety of common metals, including aluminum (of 99.5 percent purity), copper, pure iron or cast iron, steel (including cast steel and chrome-nickel steels), lead (up to 250°F or 12 PC), nickel, and silver it is also compatible with platinum and platinum alloys in instruments. Nonmetallic materials with which liquid anhydrous phosgene is also compatible include acid resistant linings (ceramic plates and carbon blocks), enamel on cast iron or glass-lined steel, Pyrex or Kimax, porcelain, quartzware, granite or basalt natural stone, stoneware, and Teflon. 

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