Blast furnace construction

C20-0017. Construct a flowchart that summarizes the chemistry that takes place in a blast furnace. 

At some plants the blast furnace dust is recycled as feedstock to the sinter plant. At plants without sintering operations, blast furnace dust is sometimes mixed with other byproduct residues, briquetted, and recycled back to the blast furnace. In other plants, the dust is landfilled or stockpiled.1 Several techniques are available for removing the zinc and lead. The majority of blast furnace sludge is land disposed as solid waste or stockpiled. Because of the similarity between wastewater sludges generated by sinter plants and blast furnaces, these streams are commingled and cotreated.1 The blast furnace slag is cooled and processed to be reused for various applications such as onsite in-land reclamation and landfill construction. 

NSA, Processed Blast Furnace Slag The All Purpose Construction Aggregate, 188.1, National Slag Association, Alexandria, VA, 1988. 

The next step in formulating the problem is to construct a mathematical model of the process by considering the fundamental chemical and physical phenomena and physical limitations that influence the process behavior. For the case of the blast furnace, typical features are... 

Reverberatory furnaces were constructed by Lambert in Chile in 1842, and the first blast furnace was erected by him in that country in 1857. So successful was the development of this enterprise, that Chile became the world s largest producer in the years 1861 to 1870, and furnished about half the total output. The decline of the Welsh industry dates from this period, and also the development of the manufacture in the United States of America, Calumet, in the Lake Superior district, becoming an important centre. The next decade is noted for the inception of copper-mining in Spain and Portugal, the chief centres being the Andalusian, San Domingo, Tharsis, and Rio Tinto mines. 

Sheppard, W.L., Jr., Materials of Construction of Pickling Tanks, Blast Furnace and... 

Carbon refractories. Carbon blocks used in the construction of blast-furnace hearths are made from dense coke possibly mixed with anthracite. Suitable grain-size fractions (up to 5—15 mm) are mixed with tar to a plastic mass which is shaped at elevated temperature by pressing or ramming. The products are fired without air at about 1400 °C in saggers covered with fine-grained coke. The carbonized tar produces a firm bond between the grains. Granular mixes arc also used in certain applications. 

The most important of all materials which enter into the construction of chemical apparatus is iron. It is usual to distinguish three kinds which are used in the arts and manufactures, viz., cast-iron, wrought-iron, and steel. But in order to obtain the best technical effects from them it is necessary to make further distinctions, and to consider their properties more in detail, particularly when they have to be used for special purposes. Ordinary grey cast-iron, as it comes from the blast furnace, contains from 2 to 4white cast-iron the carbon is chemically combined with the iron. It may contain manganese in varying quantities, from 1 to over 20 per cent. In steel, the quantity of carbon is more than per cent. in wrought-iron, less. 

Petroleum coke, obtained by subjecting the distillation bottoms to pyrolitic polymerization and thermal decomposition in a delayed or fluid coker, is used in the manufacture of calcium and silicon carbides, electrodes for aluminum manufacturing, and graphite. It also finds use as a utility fuel and as a construction material in foundry and blast furnaces. 

Contact dermatitis can occur from exposure to cement and has been considered an occupational hazard for construction workers (Turk and Rietschel 1993 Roto et al. 1996 Zachariae et al. 1996). The problem develops because chromium(VI)-con-taining residues from blast furnaces are incorporated into cement. Some countries add ferrous sulfate to cement to reduce the amount of soluble hexavalent chromate in the product (Turk and Rietschel 1993 Roto etal. 1996 Zachariae etal. 1996). In the UK, chromium and chromates accounted for 8.1% of the allergic contact dermatitis cases (Meyer et al. 2000). In Finland, chromium causes 5.6% of ACD, with tanners, cast concrete workers, leader goods workers, and metal plating/coating workers being at greatest risk (Kanerva et al. 2000). In Denmark, the chromium(VI) content of 35% of... 

Over the centuries, other pozzolanic substances were blended with slaked lime to produce what are now called synthetic (or artificial) hydraulic limes. Both naturally occurring pozzolans (such as trass, found in Germany), and synthetic pozzolans (such as ground blast furnace slag) have been, and still are used. It was also found that some impure limestones, containing silica and alumina, produced slaked limes with a range of hydraulic properties. Such natural hydraulic limes were widely used in construction and building for mortar and concrete. 

Table I - Technical Development at the Lead Smelter BERZELIUS Stolberg GmbH 1854 Construction of a 100m high stack 1892 Modernisation of Blast Furnace 1903 Construction of New Sinter Plant 1905 Implementation of first Electrostatic Precipitator 1920 Commissioning of Rotary Furnaces 1956 Construction of Up-draught Sinter Machine 1960 Construction of Sulphuric Acid Plant 1964 Commissioning of Battery Scrap Breaking Facility 1967 Start of Construction of Bagfilter Facilities 1979 Installation of Two New Rotary Furnaces 1990 Commissioning of the QSL-Plant ...

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