Chamber plants

A problem associated with plant inspection is the coupling of the probe to the metal under examination. The exterior surface of plant can be covered in rust which causes problems in coupling the probe to the metal and results in spurious and inaccurate results. Often operators move the probe to an area where adequate coupling is obtained, circumventing the real objective of the measurement. It is often impossible to obtain any coupling on severely corroded steel surfaces, e.g. the interior of flash distjllation plant chambers. 

Figure 17.22 A concept of plant growth chamber covered with surface regolith for radiation shielding. Light could be collected with solar concentrators and piped into the plant chamber (source Sadler and Giacomelli, 2002).

Data in Table 3 illustrate the use of our whole plant chambers for... 

The aspen leaves were wounded using scissors in the experiment, for which the plant chamber was quickly opened and closed (Figure 52.8). A rapid peak of mass (Z)-3-hexenal emission is observed. This behavior is consistent with the role of (Z)-3-hexenal as the precursor in the degradation process (see Figure 52.7). The rapid decline in (Z)-3-hexenal takes place simultaneously with the rise of other hexenyl derivates.The detection of hexanal is complicated by the lack of unique fragments, but the time evolution of n-hexanol and... 

A related fertilizer was anunonium sulfate. In 1901, Dominion Steel and Coal Corporation opened a sulfuric acid plant (Chamber process) to produce ammonimn sulfate in Sydney, NS. The plant first used p5oites from Newfoundland, but later switched to imported elemental sulfur. The ammonia was a byproduct from their coke ovens. This facility was the first ammonium sulfate plant in Canada. By 1946,400,000 tonnes of sulfuric acid (100% basis) was used by the fertilizer industry, representing over 75% of the acid consumed in this coimtry. 

Since the catalyst is in the gaseous state, it is being continually removed from the mixing chambers. Its recovery, and the necessity of continual charging of the incoming gases with it, make the lead chamber plant complicated by comparison with that of the Contact process. 

The Aromax process was developed in the early 1970s by Toray Industries, Inc. in Japan (95—98). The adsorption column consists of a horizontal series of independent chambers containing fixed beds of adsorbent. Instead of a rotary valve, a sequence of specially designed on—off valves under computer control is used to move inlet and withdrawal ports around the bed. Adsorption is carried out in the Hquid phase at 140°C, 785—980 kPA, and 5—13 L/h. PX yields per pass is reported to exceed 90% with a typical purity of 99.5%. The first Aromax unit was installed at Toray s Kawasaki plant in March 1973. In 1994, IFP introduced the Eluxyl adsorption process (59,99). The proprietary adsorbent used is designated SPX 3000. Individual on-off valves controlled by a microprocessor are used. Raman spectroscopy to used to measure concentration profiles in the column. A 10,000 t/yr demonstration plant was started and successfully operated at Chevron s Pascagoula plant from 1995—96. IFP has Hcensed two hybrid units. 

A furnace is a device (enclosure) for generating controlled heat with the objective of performing work. In fossil-fuel furnaces, the work appHcation may be direct (eg, rotary kilns) or indirect (eg, plants for electric power generation). The furnace chamber is either cooled (waterwaH enclosure) or not cooled (refractory lining). In this article, furnaces related to metallurgy such as blast furnaces ate excluded because they ate coveted under associated topics (see... 

Commercially, the burner chamber and the absorber cooler sections are combined as a single unit for small-scale production. However, in large capacity plants, these units are separated. A typical commercial unit is schematically described in Figure 5 (32). 

Because the highest possible interfacial area is desired for the heterogeneous reaction mixture, advances have also been made in the techniques used for mixing the two reaction phases. Several jet impingement reactors have been developed that are especially suited for nitration reactions (14). The process boosts reaction rates and yields. It also reduces the formation of by-products such as mono-, di-, and trinitrophenol by 50%. First Chemical (Pascagoula, Mississippi) uses this process at its plant. Another technique is to atomize the reactant layers by pressure injection through an orifice nozzle into a reaction chamber (15). The technique uses pressures of typically 0.21—0.93 MPa (30—135 psi) and consistendy produces droplets less than 1 p.m in size. The process is economical to build and operate, is safe, and leads to a substantially pure product. 

In wetted-wall units, the walls of a tall circular, slightly tapered combustion chamber are protected by a high volume curtain of cooled acid flowing down inside the wall. Phosphoms is atomized by compressed air or steam into the top of the chamber and burned in additional combustion air suppHed by a forced or induced draft fan. Wetted-waU. plants use 25—50% excess combustion air to reduce the tail-gas volume, resulting in flame temperatures in excess of 2000°C. The combustion chamber maybe refractory lined or made of stainless steel. Acid sprays at the bottom of the chamber or in a subsequent, separate spraying chamber complete the hydration of phosphoms pentoxide. The sprays also cool the gas stream to below 100°C, thereby minimising corrosion to the mist-collecting equipment (typically type 316 stainless steel). 

Standard Chemical Pump. In 1961, the American National Standards Institute (ANSI) iatroduced a chemical pump standard (29), known as ANSI B73.1, that defined common pump envelope dimensions, connections for the auxiUary piping and gauges, seal chamber dimensions, parts mnout limits, and baseplate dimensions. This definition was to ensure the user of the availabiUty of iaterchangeable pumps produced by different manufacturers, as well as to provide plant designers with standard equipment. A typical ANSI chemical pump, known as of the mid-1990s as ASME B73.1M-1991, is shown ia Figure 6. 

Enerco, Inc. (Yardley, Pennsylvania) has a 600 tine/d demonstration pyrolysis plant located in Indiana, Pennsylvania. The faciUty operated 8 h/d, 5 d/wk for six months. The process involves pyrolysis in a 5.4 t/d batch-operated retort chamber. The heated tines are broken down to cmde oil, noncondensable gases, pyrolytic filter, steel (qv), and fabric waste. In this process, hot gases are fed direcdy to the mbber rather than using indirect heating as in most other pyrolyses. The pyrolysis plant was not operating as of early 1996. 

Large sulfuric acid plants are based on spray burners, where the sulfur is pumped at 1030—1240 kPa (150—180 psig) through several nossles iato a refractory-lined combustion chamber. An improved nossle, resistant to plugging or fouling, has been iatroduced (256). The combustion chambers are typically horizontal baffle-fitted refractory-lined vessels. The largest plants ia fertiliser complexes bum up to 50 t/h of sulfur. 

Spinning-cup atomisers are used ia some plants to provide finer atomisation, allowiag smaller burner chambers and easier turndown, but with the burden of added rotating equipment. Rotary kiln burners were once popular to bum lower quaHty sulfur, but few are stiU ia operation. Spray burners can be operated intermittently and used at higher rates than rotary burners. 

Some of the melted ziac is fed to the ziac-dust unit where the molten ziac may be dropped from a cmcible through a small orifice (2.5 mm) to be atomized ia a blast of air. SoHdifted droplets are collected ia a chamber and screened to the proper size for purification and cadmium plant cementation. Frequently, coarse (+70 200 and fine (—70 fiva) fractions are required. 

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