Quality raising steam

Quality C2 of Energy Demand For Raising Steam and Heating Stock... 

When starting a new water treatment program, both baseline and operational information regarding levels of steam and condensate contamination generally are required. It may take several weeks of sampling work to fine-tune the program and determine any limitations with regard to steam purity and quality. Thereafter, individual control parameters such as sodium limits or antifoam concentration may need to be selectively raised or lowered in the BW and the effects tested for in the steam. 

The solution is evaporated to dryness under reduced pressure on a water bath. In order to remove as much hydrochloric acid as possible, the temperature of the bath is raised to 100° toward the end of the distillation. The residue of amino acid hydrochloride and inorganic salts is suspended in 500 cc. of absolute ethyl alcohol. The suspension is boiled on a steam bath for a short time, then cooled to room temperature and filtered on a Buchner funnel. The residue of inorganic salts is washed with 500 cc. of absolute ethyl alcohol. To the combined filtrates is added 400 cc. of ethyl ether (u. s. p. quality) in order to precipitate inorganic material. After several hours the mixture is filtered, and the residue is washed with a 5 2 mixture of absolute ethyl alcohol and ether. The filtrate is transferred to a 5-1. round-bottomed flask, about 200 cc. of water is added, and the liquids are removed by distillation under reduced pressure. The nearly dry residue is dissolved in 2 1. of water, and the solution is treated with an excess of freshly prepared lead hydroxide (Note 5). The suspension is diluted with water to a volume of about 3.5 1. and is then concentrated under reduced pressure, at as low a temperature as possible, to a volume of about 2 1. The suspension is then filtered with suction (Note 6), and the residue of lead salts is washed thoroughly with water. The cloudy filtrate, which still contains some free ammonia, is concentrated by distillation under reduced pressure to a volume of about 300-400 cc. The mixture is filtered, the filtrate is saturated with hydrogen sulfide gas, and the precipitate of lead sulfide is removed by filtration with suction (Note 6). The solution is now concentrated by distillation under reduced pressure on a water bath, and 1 1. of 95 per cent ethyl alcohol is added to the nearly dry residue of the amino acid. The suspension is boiled under a reflux condenser until nearly all the amino acid is dissolved, and the mixture is then allowed to cool to room temperature. The amino acid, which separates in the form of fine needles, is collected on a Buchner funnel and washed with a little 95 per cent ethyl alcohol. A second crop of... 

The means by which the coal is mixed with the binder and the method of heating the mixture largely determines the quality of the final product. The dried coal leaves the dry coal bunker at a temperature of 30°C-80°C (85°F-175°F) depending on size of the bunker and the transportation distance. After the metered addition of the solid or liquid binder, the mixture is conveyed to a pug mill heated by superheated steam, where its temperature is raised to about 20°C-25°C (36°F-45°F) above the softening point of the binders. 

Other ways to improve needle coke quality include minimizing steam in the healer passes, reducing the gravilily of the recycle gas oil, and raising the coke drum pressure. 

The steam turbine of AHWR is designed for a steam quality of 99.75%. During normal operation or in a bypass mode of operation the steam from the turbine exhaust is condensed in a condenser, which rejects the heat to seawater. The condensate is heated in heat exchangers by the moderator system. The feed water temperature is finally raised to 403 K through LP (low pressure) heaters and de-aerators using the steam bled from the turbine. The feed water pumps then pump the feed water into the steam drum where it mixes with the water separated from steam-water mixture. 

In order to preserve the neutron balance, the coolant cross section area must be a minimum and the steam quality not too low this raises mechanical and heat transfer problems. On the other hand, a positive void coefficient cannot be prevented, whence three difficulties ... 

About 260 lb of wood chips are fed into the cylinder and steamed to 600 psi for 30 to 60 seconds. Then the pressure is quickly raised to 1000 psi (about 285°C) and held only about 5 seconds before sudden release of the charge into a cyclone. The time of treatment at this high pressure and temperature is critical and depends upon the species of wood, chip size, moisture content, and quality of product desired. The steam is condensed in the cyclone, and the exploded fiber falls into a stock chest where it is mixed with water and pumped through washers, refiners, and screens. 

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