Lance processes using

Basic oxygen furnaces (BOFs) have largely replaced open hearth furnaces for steelmaking. A water-cooled oxygen lance is used to blow high-purity oxygen into the molten metal bath. This causes violent agitation and rapid oxidation of the carbon, impurities, and some of the iron. The reaction is exothermic, and an entire heat cycle requires only 30-50 min. The atmospheric emissions from the BOF process are listed in Table 30-16. 

The patient then needs to be prepared. In the case of the heel prick, a leg of the infant is massaged or warmed so as to increase circulation to the heel where the puncture is to be made. The site from which the collection of blood is made, is determined by the size of the infant. In prematures, where the fingers are extremely tiny, one has no choice but to obtain the specimen from the heel. In older children, the large toe may be used. In using the heel, one does not use the bottom of the heel because here the capillaries lie deep. One uses instead the back of the heel, where the capillaries come near the surface. Generally, sterile scapel blades or lances are used to puncture the skin and obtain the blood flow. Figure 8 illustrates the process of obtaining the specimen. 

Fig. 2 The improved pneumatic lance is constructed from concentric tubes. Low-speed aeration from both tubes allows the lance to be inserted with minimum disturbance to the powder supply. Once the sampling location is reached, a high-speed flow is applied to the central tube to capture a sample below the filter or frit. (A) Construction of the pneumatic sampler (B) process used to obtain a sample from a bulk of powder.

As an indication of the flexibility of the EAF, it is used in some developing countries for the direct reduction of iron ore by carbon [27.18]. The furnace is charged with iron ore intimately mixed with ground carbon. Quicklime, calcined dolomite and fluorspar are added and an oxygen lance is used to oxidise the impurities much as in the BOS process. The slag is removed and the chemical... 

In addition to many varied apphcations in the chemical industiy, the reactotherm is widelv used to process waste sludges which must be dried in order to lanc fill the sohd components. In many of these cases, the solvents are valuable components of the waste stream and can be recovered and recycled. 

Ajax An oxygen steelmaking process in which the oxygen is injected into an open hearth furnace through water-cooled lances. Used at the Appleby-Frodingham steelworks, UK. 

Brittania A process for removing silver from lead, operated by Brittania Refined Metals in England, using ore from the Mount Isa mine in Australia. After initial concentration by the Parkes process, and removal of the zinc by vacuum distillation, the mixture, which contains silver (70 percent), lead, and some copper is treated in a bottom blown oxygen cupel in which lead and copper are removed by the injection of oxygen through a shielded lance. 

Isasmelt A two-stage lead smelting process. In the first stage, the lead concentrate is oxidized by injecting air down a Sirosmelt lance, using helical vanes to swirl the gas. In the second, the high-lead slag is reduced with coal. The process was developed by Mount Isa Mines and the CSIRO, Australia, and due for startup at Mount Isa in 1991. 

SIP requirements, in air quality management, 1 812 Sips adsorption isotherm, 1 626 Siroflash process, 26 398 Siroscour technology, 26 384 Sirosmelt lance, 14 743 Sisal, 11 297 uses of, ll 299t... 

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