Metal oxide fumes

Gases from the sintering process contain SO2, dust, and metal oxide fumes. The blast furnace gases contain similar particulates plus SO2 and CO. Table 30-10 indicates the expected SO2 emissions. 

The development of electrostatic precipitators soon led to new applications, including the separation of metal oxide fumes. This was followed by various metal manufacturing processes such as the lead blast furnace, ore roaster, and reverberatory furnace. Electrostatic gas cleaning was soon applied also in cement kilns and in several exotic applications, such as recovering valuable metals from exhaust gases. 

Thermal decomposition—Thermal decomposition methods may be used to prepare metal oxide fumes. An aerosol of a precursor to the metal oxide (i.e., a substance that is readily decomposed, thermally, to yield the oxide) is first generated and then is heated by passing it through a heated tube to decompose it to the oxide. Metal formates, oxalates, and the like, which readily yield the oxides and do not produce objectionable side products, are commonly used precursors. In this program, fumes of iron oxide, vanadium oxide, and copper oxide were generated using this method. 

Industrial accidents in which the combustion of organometallic compounds generates respirable, toxic metal oxide fumes can certainly pose a hazard. 

Metal oxide fumes Thermal degradation of organic precursor... 

Metal Oxide Fume Generator. Figure 11 shows a metal oxide fume generator that has been used for such materials as magnesium and copper oxides. 

Reverberatory furnace Smoke, particulates, metal oxide fumes, Exhaust system, settling chambers,... 

Mori T, Akashi S, Nukada A. 1975. Effects of the inhalation of catalytically active metallic oxide fumes on rabbits. Int Arch Occup Environ Health 36 29-39. Morrison GMP, Revitt DM, Ellis JB. 

All industrial processes release dusts other than soot. There are many sources and forms including fuel ash, metal oxide fumes and silica and releases tend to be localized. Fugitive emissions from outdoor industrial activity or processes associated with the mining and preparation of raw materials can generally be controlled through careful industrial practice. Water is often used to minimize dust raised, resulting in the transfer of an atmospheric pollution problem to one of either aquatic or solid waste. 

Hazardous Decomp. Prods. Heated to decomp., emits initating metal oxide fumes HMIS Health 2, Flammability 2, Reactivity 2... 

Carhon monoxide Fuming of metallic oxides, gas-operated fork trucks Primary metals steel and aluminum Reduction in oxygen-carrying capacity of blood... 

NO -laden fumes are preheated by effluent from the catalyst vessel in the feed/effluent heat exchanger and then heated by a gas- or oil-fired heater to over 600° F. A controlled quantity of ammonia is injected into the gas stream before it is passed through a metal oxide, zeolite, or promoted zeolite catalyst bed. The NO is reduced to nitrogen and water in the presence or ammonia in accordance with the following exothermic reactions ... 

Emissions from other nonferrous metal facilities are primarily metal fumes or metal oxides of extremely small diameter. Zinc oxide fumes vary from 0.03 to 0.3 jiim and are toxic. Lead and lead oxide fumes are extremely toxic and have been extensively studied. Arsenic, cadmium, bismuth, and other trace metals can be emitted from many metallurgical processes. 

Gas-solid Fume Metal oxides, cement dust... 

Gas Gas-vapour Gas-liquid Gas-solid Gas-liquid-solid Mist Fume SO2 NOxI HCI CO hydrocarbons Acid mist carryover chromic acid oil mists tar fog Metal oxides, cement dust Paint spray... 

The effects of various metal oxides and salts which promote ignition of amine-red fuming nitric acid systems were examined. Among soluble catalysts, copperQ oxide, ammonium metavanadate, sodium metavanadate, iron(III) chloride (and potassium hexacyanoferrate(II) with o-toluidine) are most effective. Of the insoluble materials, copper(II) oxide, iron(III) oxide, vanadium(V) oxide, potassium chromate, potassium dichromate, potassium hexacyanoferrate(III) and sodium pentacyanonitrosylferrate(II) were effective. 

Hydrochloric acid. Strong acids are used frequently for the purpose of sample dissolution when water will not do the job. One of these is hydrochloric acid, HC1. Concentrated HC1 is actually a saturated solution of hydrogen chloride gas, fumes of which are very pungent. Such a solution is 38.0% HC1 (about 12 M). Hydrochloric acid solutions are used especially for dissolving metals, metal oxides, and carbonates not ordinarily dissolved by water. Examples are iron and zinc metals, iron oxide ore, and the metal carbonates of which the scales in boilers and humidifiers are composed. Being a strong acid, it is very toxic and must be handled with care. It is stored in a blue color-coded container. 

Welders are typically exposed to a complex mixture of dust and fume of metallic oxides, as well as irritant gases, and are subject to mixed-dust pneumoconiosis with possible loss of pulmonary function this should not be confused with benign pneumoconiosis caused by iron oxide. Although an increased incidence of lung cancer has been observed among hematite miners exposed to iron oxide, presumably owing to concomitant radon gas exposure, there is no evidence that iron oxide alone is carcinogenic to man or animals. ... 

Jones JG, Warner CG Ghronic exposure to iron oxide, chromium oxide, and nickel oxide fumes of metal dressers in a steelworks. Br J IndMed 29-. 69-m, 1972... 

In a very early report, experimental subjects exposed to fresh magnesium oxide fume developed metal fume fever, an illness similar to influenza effects were fever, cough, oppression in the chest, and leukocytosis. After the introduction of a new process resulting in exposure to magnesium oxide fume in the 1980s, several German foundry workers developed recurrent occupational fever that was also interpreted as metal fume fever. ... 

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