Process boilers

Once an undesirable material is created, the most widely used approach to exhaust emission control is the appHcation of add-on control devices (6). Eor organic vapors, these devices can be one of two types, combustion or capture. AppHcable combustion devices include thermal iaciaerators (qv), ie, rotary kilns, Hquid injection combusters, fixed hearths, and uidi2ed-bed combustors catalytic oxidi2ation devices flares or boilers/process heaters. Primary appHcable capture devices include condensers, adsorbers, and absorbers, although such techniques as precipitation and membrane filtration ate finding increased appHcation. A comparison of the primary control alternatives is shown in Table 1 (see also Absorption Adsorption Membrane technology). 

Compounds considered carcinogenic that may be present in air emissions include benzene, butadiene, 1,2-dichloroethane, and vinyl chloride. A typical naphtha cracker at a petrochemical complex may release annually about 2,500 metric tons of alkenes, such as propylenes and ethylene, in producing 500,000 metric tons of ethylene. Boilers, process heaters, flares, and other process equipment (which in some cases may include catalyst regenerators) are responsible for the emission of PM (particulate matter), carbon monoxide, nitrogen oxides (200 tpy), based on 500,000 tpy of ethylene capacity, and sulfur oxides (600 tpy). 

High pressure 2-50 MW Yes All types (mainly classes G and H) 6-20 20 3 1 to 12 1 Mainly wide-angle sprays in WT boilers, low excess operation Large shell boiler and watertube boiler process apphcations... 

Solubilization of a solid phase by complex formation. This chelation solubilization is used for deposits and scale in boilers, processing tanks, and oxide films of metals [Na2Mg(edta), NH4Fe (edta), NaFe(edta), (NH4)3H(edta)]. 

Lighting Heating Appliances Heating Lighting Boiler Process ... 

Two streams of water are mixed to form the feed to a boiler. Process data are as follows ... 

The fuel gas can be used in conventional end use systems, such as steam boilers, process and liquid air heaters, and large industrial furnaces. 

Compared to those of large steam boilers, process heater temperatures are relatively low. 

The urea-based NOxOUT process has demonstrated high NOx eduction while inirmnizing NH3 slip in CO boilers, process heaters, and waste incinerators located in refineries and petrochemical plants. The high performance was achieved under... 

Because the reactor is basically a water boiler, process systems are required which clean and control the chemistry of the water in the reactor vessel as well as protect the reactor core. Called the reactor auxiliary systems, these systems may be divided into two general... 

The by-product stream can be divided into two types, according to their sites, the built-in form inside the catalyst bed and built-out form outside the catalyst bed. The built-in form is not to be used now because of its complicated structures and the low volumetric coefficient of the converter. The built-out form of by-product steam can be subdivided into three sorts Front-type, mid-type and back-type according to their sites in which the heat is recovered (shown in Fig. 9.23). In front-type boiler process, the reaction gas from the catalyst bed enters into waste heat boiler to recover the reaction heat, and then enters into the interchanger. It would produce high-pressure steam at 4 MPa-12.5 MPa. The mid-type waste heat boiler is located between the first and the second interchanger, the temperature of reaction gas is lower than that in front-type boiler, and can only produce steam at 0.9-1.6 MPa. The back-type boiler is applicable to outlet gas at low-temperatm-e of the converter. 

In refineries, carbon monoxide (CO) is formed by incomplete combustion in boilers, process heaters, power plants, and FCC regenerators. CO is toxic because it binds strongly to the hemoglobin in blood, displacing oxygen. It is colorless and odorless, so without a special analyzer, it is hard to detect. This adds to its danger. 

CO from by partial combustion in FCC regenerators is converted to CO2 in CO boilers. Flue gas from other boilers, process heaters, and power plants can also contain some CO, which can be diminished by the installation of high-efficiency burners and/or the implementation of advanced process control. 

Ste.itn from Boilers Process steam latent bent only a. Low pressure (5bargr 160°C) from ... 

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