Process condensates

As in all the processes, the process condensate and all other sources of waste urea—NH —water contamination go to a waste recovery unit which includes a urea hydrolyzer. The final water discharge is then below 3—5 ppm of NH and urea. 

Compounds having low vapor pressures at room temperature are treated in water-cooled or air-cooled condensers, but more volatile materials often requite two-stage condensation, usually water cooling followed by refrigeration. Minimising noncondensable gases reduces the need to cool to extremely low dew points. Partial condensation may suffice if the carrier gas can be recycled to the process. Condensation can be especially helpful for primary recovery before another method such as adsorption or gas incineration. Both surface condensers, often of the finned coil type, and direct-contact condensers are used. Direct-contact condensers usually atomize a cooled, recirculated, low vapor pressure Hquid such as water into the gas. The recycle hquid is often cooled in an external exchanger. 

Process condensate from reforming operations is commonly treated by steam stripping. More recentiy the stripper has been designed to operate at a... 

Process condensate from reforming operations is commonly treated by steam stripping. The stripper is operated at a sufficiently high pressure to allow the overhead stripping steam to be used as part of the reformer steam requirement (71). Contaminants removed from the process condensate are reformed to extinction, so disposal to the environment is thereby avoided. This system not only reduces atmospheric emissions, but contributes to the overall efficiency of the process by recovering condensate suitable for boiler feedwater make-up because the process is a net water consumer. 

Incorporation of a feed gas saturator cod in the convection section of the primary reformer allows for 100% vaporization of the process condensate. The steam is used as process steam in the reformer. 

Dust-laden streams can also cause operational problems. A turboexpander that can efficiently process condensing streams (gas with fog droplets suspended) can usually handle a stream with suspended solid particles, as long as the particle size does not exceed 2-3 p. The newer designs reduce erosion of expander back rotor seals by disposing of... 

Evaporation of liquid to form vapour is accompanied by a considerable increase in volume. For example, at atmospheric pressure one volume of water will generate 1600 volumes of steam. Similarly 4.54 litres of gasoline will yield 0.93 m of neat vapour on complete vaporization. The reverse process, condensation, is accompanied by a considerable - and often rapid - decrease in volume. As a result ... 

The reader is encouraged to select other chemical process condensation processes and obtain information on physical and chemical properties, healtli effects, and methods of manufacture, and causes for potential accidents. This is obviously an open-ended question, therefore no solution is provided. 

The non-condensables leaving a surface condenser are saturated with water vapor at the temperature corresponding to the pressure. For a process condenser the vapor corresponds to the process fluid. 

Fine Aitken nuclei, transient lifetime High temperature combustion processes, condensation from the vapour... 

Horizontal shell-side and vertical tube-side are the most commonly used types of condenser. A horizontal exchanger with condensation in the tubes is rarely used as a process condenser, but is the usual arrangement for heaters and vaporisers using condensing steam as the heating medium. 

Addition polymerization may proceed through a free radical, cationic or anionic process. Condensation polymers, on the other hand, are formed by elimination of small molecules like that of water, alcohol or ammonia in the reaction of monomeric units, e.g. 

The manufacture of fatty acid from fat is called fat splitting (B), and the process flow diagram is shown in Fig. 3. Washouts from the storage, transfer, and pretreatment stages are the same as those for process (A). Process condensate and barometric condensate from fat splitting will be contaminated with fatty acids and glycerine streams, which are settled and skimmed to recover... 

In ammonium phosphate production and mixed and blend fertilizer manufacturing, one possibility is the integration of an ammonia process condensate steam stripping column into the condensate-boiler feedwater systems of an ammonia plant, with or without further stripper bottoms treatment depending on the boiler quality makeup needed. 

In ammonium phosphate and mixed and blend fertilizer (G) production, another possibility is to design for a lower-pressure steam level (i.e., 42-62 atm) in the ammonia plant to make process condensate recovery easier and less costly. 

Dixharge valve is pressed open, and particles of vapor and gas are pushed out -the overpressure required for this to occur is reached very early because of the supplementary gas ballast air, as at the beginning the entire pumping process condensation cannot occur... 

A series of complexometric extractions were performed to optimize the mobUiza-tion/purging of metallic ions from samples of processing condensate of chromated copper arsenate (CCA). Whereas Cr(VI) and Cu(II) were rapidly mobilized into isobu-tylmethyl ketone-amended SCCO2 after reaction with dithiocarbamate or alkylxan-... 

Vapors from stripping process condensate may contain phenols and oil matter. With proper design these compounds can be oxidized completely to CO2 and CO. Incomplete oxidation leads to formation of tars which can block Claus catalyst beds. 

The different processes, condensation, substitution of positive ions... 

Chap. 8, your analysis is correct. A steam reboiler has the same problems, and works on the same principles as a process condenser. The only difference is that a steam reboiler s heat is removed by the shell-side process fluid, and a process condenser s heat is removed by cooling water. 

Fig. 7.6. Industrial-scale processing condensation of adipic acid (B) and ammonia to adipic acid diamide (D) and its thermal dehydration to adipic acid dinitrile (C). On a very large scale, adipic acid dinitrile is hydrated to give 1,6-diamino-hexane ("hexamethylenedi-amine ), which is further processed to furnish nylon-6,6 ("nylon").

After shift conversion, the gas is cooled by direct contact with circulating process condensate and then fed to a pressure swing adsorption (PSA) unit to remove excess nitrogen, CO2 and inerts. The C02 can be recovered from the pressure swing adsorption waste gas by using an aqueous solution of tertiary... 

The physical and chemical properties of analytes and the nature of the sample have a major impact on, and often limit, the sampling and other procedures and techniques that can be employed in an analytical method. Major issues that must be considered when developing an analytical method are the volatilities, thermal stabilities, photochemical stabilities, polarities, water solubilities, and chemical reactivities of the sample components or target analytes the physical state of the sample and the nature of the sample matrix. Analytes, whether organic or inorganic, can be broadly divided into three categories based partly on vapor pressure, or volatility, at ambient temperature and on some other physical and chemical properties. There are major differences in the procedures and techniques used to acquire and process condensed-phase and vapor-phase samples. 

A physical explosion process which, like the Armstrong process and Airdox process, operates on the principle of a sudden release of compressed gas by means of a bursting disc. In the Cardox process, condensed C02 is brought to a high vapor pressure by means of a... 

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