Sulfur admission

Figure 12. Transient HCN yield over platinum catalysts. A and B represent one experiment (Exp. 1) in which a sulfur-poisoned catalyst was regenerated on admission of 1% O2 into the inlet gas mixture between times t, and C shows the resistance of the catalyst to poisoning by SO when oxygen is simultaneously present in the inlet gas mixture. At t only oxygen is removed from the inlet gas mixture. (See Ref. 16 for details.)...

Automatic Controls. A certain amount of automatic control of process operating conditions is necessary to cope with frequent large changes in sulfur dioxide content of the gas. A sulfur dioxide analyzer, indicating the sulfur dioxide content of the gas at the main blower, controls the admission of dilution air to the drying tower when the sulfur dioxide content of the feed gas exceeds 8%. A second analyzer records the sulfur dioxide content of the gas leaving the final absorber. 

Although the practice of sulfuring fruit for drying was widely used in California in the late nineteenth century, it apparently was not recognized abroad. In 1902, Beythien and Bohrisch discovered that practically all the dried fruit imported into Germany from America was heavily sulfured and this observation was followed by publication of numerous papers in which the admissibility of sulfur dioxide as a preservative was actively debated (Beythien and Bohrisch, 1902, 1903). 

Sulfur also is harmful to the iron. It gives socrack formation in the red-hot state. The ores are roasted before processing. Roasting is heating with full air admission so that the sulfur in the ore is oxidized to sulfur dioxide, which disappears. The risk of red brittleness in the iron is decreased or ehminated. 

Even in small amounts, sulfur compounds are extremely harmful to the activity of most catalysts used in fuel cells. The admissible amounts of these impurities are in the ppb (parts per billion) range. In larger amounts, sulfur contaminants will also be harmful to hydrocarbon fuel reforming. 

A little more aging may occur in the bottle, as the sulfur dioxide content decreases gradually. Corked bottles of wine are stored with the cork end inclined downward so that the cork is kept wet and the admission of air is prevented. NOTE WELL In 1991, the Food and Drug Administration issued a temporary standard for wine prohibiting the sale of wine with more than 300 parts per billion of lead as a temporary measure until a permanent standard can be set. Also, FDA has said that it will soon propose a ban on lead foil wrappers to cover corks in wine bottles. 

The first lead chamber was 1.8 meters square, and 8 1 mixtures of sulfur and saltpeter in iron carts were rolled into it and burned with intermittent admission of air." As in the... 

Air admission to the combustion zone is controlled so that sulfur is oxidized to SO2 only, thereby minimizing SO3 formation. This is because the sulfates that arise from reactions with metals present (such as Mg, Ca and Fe) may melt to form slag. Slag is an accumulation of non-volatile materials that can adhere to the furnace walls, thereby opposing the transfer of heat to the water beyond. The presence of SO3 can also result in boiler corrosion. 

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