Matte treatment

Meadows, N. E. Valenti, M. The BHAS copper-lead matte treatment plant. Publ. Australas. Inst. Min. and Metall. 1989, 6/89, 153-157. 

Any lead bullion recovered from matte treatment will be rich in copper and can form a significant circulating load through the lead bullion refining stage (see Chapter 12 - Copper Removal or Copper Drossing). 

From the copper and nickel ore concentrates platinum metals are collected in the anode sHme from the copper electrolysis or in a residue after the nickel matte treatment with CO in the MONO process. This residue and the anode slime are worked up in a noble metal refinery. 

Substantially all the zinc is absorbed by the surface of the components, and the resulting coating has a matt-grey appearance and consists essentially of a zinc-iron alloy averaging 90-95% Zn. If excess zinc is made available and the treatment is prolonged, pure zinc is deposited at the surface. 

The conversion process for the copper matte removes iron, sulfur and other impurities from matte, thereby yielding liquid metallic copper of about 99% purity (blister copper). The slags which come out of converters contain from 2 to 15% copper and must go through treatment for copper recovery, usually by froth flotation of the copper from solidified and slowly cooled slag. 

Nickel sulfide concentrates are first subjected to an oxidizing treatment and then converted to nickel matte which is processed by hydrometallurgical methods. These methods have been indicated as A, C, and D in Figure 5.6. 

Various finishes can be achieved — gloss, satin (or egg-shell) or matt. This is accomplished by the addition of particles of size 1-5 pm of, for example, silica, china clay or the white pigment, TiCK The degree of mattness depends on various factors, such as particle size, surface treatment of the particles, rate of film formation, and the polymer composition, e.g., urethane/acrylate compared with epoxy/acrylate. The former requires smaller particles larger particles cannot be used as they create a rough surface. 

Societe Le Nickel (SLN) employ similar chemistry at their operations to treat mattes obtained from the pyrometallurgical treatment of Ni-bearing oxidic laterite ores.104 It has demonstrated at laboratory scale that Ni-containing lateritic ores may be directly leached into HC1 acid solution without pyrometallurgical pre-concentration at atmospheric pressure and relatively low temperature (ca. 70 °C).105... 

Sulfide ores are processed by a number of pyrometallurgical processes roasting, smelting, and converting. During these processes, sulfur and iron are removed to deld a sulfur-deficient copper-nickel matte. Especially after roasting and converting, the nickel in the matte may consist primarily of nickel subsulfide. After physical separation of the copper and nickel sulfides, the nickel is refined electrochemically or by the carbonyl process. The treatment of the matte depends on the end use of the nickel. Alternatively, the sulfide can be roasted to form a nickel oxide sinter that is used directly in steel production. 

Generally speaking, those minerals which are rich in silver, and contain large amounts of gangue of a sili-cious nature, when subjected to the preoeding treatment, give a matt which still retains a portion of the noble metal, and on that account is reserved to go through a second fusion. 

For the treatment of zinc blende roaster gases for use in the Contact Process, soe Robson, Trans. Canad. Inst. Min. and Met., 1927, 30, 950 and for the use of gases produced in the bessemerising of nickel-copper matte, see De Blois, ibid., p. 929. 

Native copper ore is crushed, concentrated by washing with water, smelted, and cast into bars. Oxide and carbonate ores are treated with carhon in a smeller. Sulfide ore treatment is complex, hut. in brief, consists of smelling to a matte of cuprous sulfide, ferrous sulfide, and silica, which molten matte is treated in a converter by the addition of lime and air is forced under pressure through the mass. The products are blister copper, ferrous calcium silicate slag, and SO . Refining is conducted by electrolysis, and the anode mud is treated to obtain the gold and silver. See Fig. I. 

In semi-automatic moulding the operator may inspect each unit for features including colour, dispersion and uniformity of colour, standard and uniformity of gloss or mattness, and the presence or otherwise of defects like silver streaks or stringing. However, it is preferable if assessments can be made in numerical terms, expressed in units that may be compared quantitatively and subjected easily to statistical treatment and analysis. It is often convenient in the course of... 

Usually, as the coated web emerges from the last zone of the oven it passes a bank of infra-red heaters (which maintain the temperature) and through a simple direct emboss nip fitted with a plain embossing roller. This treatment helps to smooth minor imperfections in the surface and gives a matt finish preparatory to printing. The roller is of steel with surface grit-blasted or (better) with a sprayed ceramic surface and water-cooled internally. 

Significant microbiologically induced corrosion due to the presence of bacteria in the water is evidenced by saucer-shaped pits, smooth sided pits, bright shiny copper to matte red clean areas. The black deposits, corrosion products from carbon steel, may cause underdeposit corrosion and may cause the failure. Treatment of the water with biocide may minimize microbiologically induced corrosion. 

Oily, greasy, or sticky residue on treatment area Appearance of treatment area (e.g. dull, slimy, matt)... 

Bryk, T., and Mryglod, I. Charge density autocorrelation functions of molten salts Analytical treatment in long-wavelength limit. J. Cond. Matt. Phys., 2004, 16, p. L463-L469. 

World nickel metal production in 2002 was 678000 tons [39]. Hydrometallurgy has typically been applied to the treatment of nickel-copper mattes, anode nickel, and reduced laterite ore. The sulfide concentrates are usually oxidized by roasting and then smelted to copper-iron-nickel sulfide matte (75-80% Cu-Ni), which is refined or used directly to make M onel metal. Cathode nickel can be produced from a variety of electrolytes, including chloride, sulfate, or a mixed chloride-sulfate. The former two are acid systems used in leaching and electrowinning. Mixed chloride-sulfate electrolytes are used for electrorefining the nickel sulfide matte from the traditional matte-smelting operations. 

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