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Thermal category

This category comprises conventional LPG (commercial propane and butane), home-heating oil and heavy fuels. All these materials are used to produce thermal energy in equipment whose size varies widely from small heaters or gas stoves to refinery furnaces. Without describing the requirements in detail for each combustion system, we will give the main specifications for each of the different petroleum fuels. [Pg.232]

Emerging technologies for the commercial manufacture of chloric acid fall into three categories (/) generation of high purity chloric acid by thermal decomposition of pure solutions of hypochlorous acid [7790-92-3], HCIO (5). [Pg.494]

Materials Thermal insulations are produced from many materials or combinations of materials in various forms, sizes, shapes, and thickness. The most commonly available materials fall within the following categories ... [Pg.1098]

These are conditions in which overheating of the machine may not trace back to its own thermal curves as in the first case. The temperature rise may now be adiabatic (linear) and not exponential and hence rapid. Now a normal thermal protection device may not be able to respond as in the previous case. Some conditions causing overheating may not necessarily be fault conditions. Nevertheless, they may require fast tripping, and hence are classilled in this category for more clarity. Such conditions may be one or more of the following ... [Pg.279]

Pasquill (11) advocated the use of fluctuation measurements for dispersion estimates but provided a scheme "for use in the likely absence of special measurements of wind structure, there was clearly a need for broad estimates" of dispersion "in terms of routine meteorological data" (p. 367). The first element is a scheme which includes the important effects of thermal stratification to yield broad categories of stability. The necessary parameters for the scheme consist of wind speed, insolation, and cloudiness, which are basically obtainable from routine observations (Table 19-3). [Pg.301]

Based upon raw material and intended application, the manufacturing of activated carbon falls into two mam categories thermal activation and chermcal activation. In general, thermal activation involves the heating/gasification of carbon at high ternperamres [13], while chemical activation is characterized by the chermcal dehydration of the raw material at significantly lower temperatures [11,14]. [Pg.239]

The main categories of electrical/optical ceramics are as follows phosphors for TV, radar and oscilloscope screens voltage-dependent and thermally sensitive resistors dielectrics, including ferroelectrics piezoelectric materials, again including ferroelectrics pyroelectric ceramics electro-optic ceramics and magnetic ceramics. [Pg.271]

This section describes the major industrial processes within the petroleum refining industry, ineluding the materials and equipment used, and the processes employed. The section is necessary for an understanding of the interrelationships between the industrial processes, the types of air emissions, and control and pollution prevention approaehes. Deseriptions of eommonly used production processes, assoeiated raw materials, by-produets produeed are first deseribed. Petroleum refining is the physieal, thermal, and chemical separation of erude oil into its major distillation fraetions, which are then further proeessed through a series of separation and eonversion steps into finished petroleum produets. The primary products of the industry fall into three major categories ... [Pg.79]

Database containing information on over 400 contractors and the treatment, storage and disposal methods they offer. Treatment is broken into onsite and offsite and then by the following categories biological, chemical, physical, and thermal treatment. Menu driven. Available through cross talk for EPA Regional offices. [Pg.307]

A controlled zone is a zone in which the thermal and air purity (quality) conditions are controlled to their specified levels. The two categories of controlled zones are as follows ... [Pg.10]

The three categories in Table 6.3 apply to spaces where persons are exposed to the same thermal environment. It is advantageous if some kind of individual control over the thermal environment can be established for each person in a space. Individual control of the local air temperature, mean radiant temperature, or air velocity may contribute to reducing the rather large differences between individual requirements and therefore provide fewer dissatisfied. [Pg.381]

Figure 6.6 and Tables 6.4-6.6 give ranges for local thermal discomfort parameters for the three categories listed in Table 6.3. The acceptable mean air velocity is a function of local air temperature and turbulence intensity. 7 he turbulence intensity may vary between 30% and 60% in spaces with mixed flow air distribution. In spaces with displacement ventilation or without mechanical ventilation, the turbulence intensity may be lower. [Pg.382]

FIGURE 6.6 Acceptable mean air velocity as a function of local air temperature and turbulence intensity for the three categories of thermal environment. [Pg.383]

TABLE 6.5 Range of Floor Temperature for Three Categories of Thermal Environment ... [Pg.383]

In addition, NaOMe, and NaNH2, have also been employed. Applieation of phase-transfer conditions with tetra-n-butylammonium iodide showed marked improvement for the epoxide formation. Furthermore, many complex substituted sulfur ylides have been synthesized and utilized. For instance, stabilized ylide 20 was prepared and treated with a-D-a/lo-pyranoside 19 to furnish a-D-cyclopropanyl-pyranoside 21. Other examples of substituted sulfur ylides include 22-25, among which aminosulfoxonium ylide 25, sometimes known as Johnson s ylide, belongs to another category. The aminosulfoxonium ylides possess the configurational stability and thermal stability not enjoyed by the sulfonium and sulfoxonium ylides, thereby are more suitable for asymmetric synthesis. [Pg.4]

Secondary recovery, infill drilling, various pumping techniques, and workover actions may still leave oil, sometimes the majority of the oil, in the reservoir. There are further applications of technology to extract the oil that can be utilized if the economics justifies them. These more elaborate procedures are called enhanced oil recovery. They fall into three general categories thermal recoveiy, chemical processes, and miscible methods. All involve injections of some substance into the reservoir. Thermal recovery methods inject steam or hot water m order to improve the mobility of the oil. They work best for heavy nils. In one version the production crew maintains steam or hot water injection continuously in order to displace the oil toward the production wells. In another version, called steam soak or huff and puff, the crew injects steam for a time into a production well and then lets it soak while the heat from the steam transfers to the resei voir. After a period of a week or more, the crew reopens the well and produces the heated oil. This sequence can be repeated as long as it is effective. [Pg.926]


See other pages where Thermal category is mentioned: [Pg.344]    [Pg.155]    [Pg.32]    [Pg.344]    [Pg.155]    [Pg.32]    [Pg.387]    [Pg.410]    [Pg.61]    [Pg.404]    [Pg.21]    [Pg.431]    [Pg.129]    [Pg.13]    [Pg.65]    [Pg.313]    [Pg.106]    [Pg.508]    [Pg.517]    [Pg.530]    [Pg.363]    [Pg.170]    [Pg.171]    [Pg.401]    [Pg.515]    [Pg.381]    [Pg.498]    [Pg.723]    [Pg.280]    [Pg.334]    [Pg.377]    [Pg.382]    [Pg.383]    [Pg.239]    [Pg.399]   
See also in sourсe #XX -- [ Pg.32 ]




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