Steam-injected cleaning

There are six major chemical cleaning methods circulation, fill and soak, cascade, foam, vapor-phase organic, and steam-injected cleaning. 

Steam-injected cleaning involves the injection of a concentrated mixture of eleaning chemieals into a stream of fast-moving steam. The steam is injected at one end of the system and condensed at the other. It atomizes the chemicals, increasing their effectiveness, and ensures good contact with the... 

Steam-injected cleaning is very effective for critical piping systems. As with foam eleaning, the method produces a relatively low amount of hquid for disposal. 

Flares. Flares are used for the combustion of waste hydrocarbon gases in which the rates may vary over a wide range and for emergency releases. Steam injection is usually used to enhance mixing and the formation of a clean flame. 

For environmental reasons, burning should be smokeless. Long-chain and unsaturated hydrocarbons crack in the flame producing soot. Steam injection helps to produce clean burning by eliminating carbon through the water gas reaction. The quantity of steam required can be as high as 0.05—0.3 kg steam per kg of gas burned. A multijet flare can also be used in which the gas bums from a number of small nozzles parallel to radiant refractory rods which provide a hot surface catalytic effect to aid combustion. 

Gas compressor steam cleaning facility with steam injection in the compressor suction main and in the discharge-side labyrinth shaft seal... 

Steam system. Clean steam is used for all equipment that comes into contact with containers, solution, or closures prior to product assembly. Pure steam is produced by a generator fed by deionized water. Steam traps are installed to collect condensate when necessary. The quality of pure steam condensate is the same as water for injection. The quality of pure steam is monitored through a quality analyzer system that measures the conductivity of condensed pure steam. 

Low-NOx Technologies for Gas Turbine Applications - The existing methods for NOx control in gas turbines may be broadly divided into primary measures to control the combustion and secondary measures to clean up the flue gas containing NOx. Primary measures include, beside catalytic combustion, water or steam injection, lean-premixed combustion and staged combustion. To... 

Steam distillation can be carried out in both batchwise and continuous plant and, since the equipment is very simple and can be used on a routine basis for preparing the plant for maintenance or for cleaning between campaigns, steam injection facilities should be fitted even when process application is not immediately foreseen. 

Bulk development n. Any of various relaxation treatments to produce maximum bulk in textured or latent crimp yarns or in fabrics made there from. The essential conditions are heat, lubrication, movement, and the absence of tension. Bulk development may be accomplished during wet processing or may be a separate operation such as hot-air tumbling, steam-injection tumbling, or dry cleaning. 

Both polyamides evolve oligomer vapor upon extrusion from the spinning holes, and snow-like deposits are formed on cold spots in the top of the spinning machine. Measures such as steam injection, suction, and regular manual cleaning must be taken to keep these under control. 

Using reboilers instead of direct steam injection to conserve clean condensate and reduce effluent volumes... 

Fresh reducing gas is generated by reforming natural gas with steam. The natural gas is heated in a recuperator, desulfurized to less than 1 ppm sulfur, mixed with superheated steam, further preheated to 620°C in another recuperator, then reformed in alloy tubes filled with nickel-based catalyst at a temperature of 830°C. The reformed gas is quenched to remove water vapor, mixed with clean recycled top gas from the shaft furnace, reheated to 925°C in an indirect fired heater, and injected into the shaft furnace. For high (above 92%) metallization a CO2 removal unit is added in the top gas recycle line in order to upgrade the quaUty of the recycled top gas and reducing gas. 

Reducing gas is generated from natural gas in a conventional steam reformer. The natural gas is preheated, desulfurized, mixed with steam, further heated, and reformed in catalyst-filled reformer tubes at 760°C. The reformed gas is cooled to 350°C in a waste heat boiler, passed through a shift converter to increase the content, mixed with clean recycled top gas, heated to 830°C in an indirect-fired heater, then injected into reactor 4. 

Power Washing. Power washing is similar to steam cleaning, except that the cleaner is injected into a high pressure (6.9—35 MPa (1000—5000 psi)) water blast in power washing. The water can be cold, warm, or hot, because the power washer is fed from a water tap. 

Nozzles used to inject a medium, such as steam, into the boiler to dislodge deposits. Used to clean the fireside during operation of the boiler. 

Care should be taken not to flood the feed nozzles since this adversely influences atomization. This happens when too little steam is used or too much feed is injected to a nozzle. Restriction orifices nsed in feed and steam lines may need to be replaced. Strainers on these lines might reqnire periodic cleaning. 

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