Industrial temperature effect

Table 1 is condensed from Handbook 44. It Hsts the number of divisions allowed for each class, eg, a Class III scale must have between 100 and 1,200 divisions. Also, for each class it Hsts the acceptance tolerances appHcable to test load ranges expressed in divisions (d) for example, for test loads from 0 to 5,000 d, a Class II scale has an acceptance tolerance of 0.5 d. The least ambiguous way to specify the accuracy for an industrial or retail scale is to specify an accuracy class and the number of divisions, eg. Class III, 5,000 divisions. It must be noted that this is not the same as 1 part in 5,000, which is another method commonly used to specify accuracy eg, a Class III 5,000 d scale is allowed a tolerance which varies from 0.5 d at zero to 2.5 d at 5,000 divisions. CaHbration curves are typically plotted as in Figure 12, which shows a typical 5,000-division Class III scale. The error tunnel (stepped lines, top and bottom) is defined by the acceptance tolerances Hsted in Table 1. The three caHbration curves belong to the same scale tested at three different temperatures. Performance must remain within the error tunnel under the combined effect of nonlinearity, hysteresis, and temperature effect on span. Other specifications, including those for temperature effect on zero, nonrepeatabiHty, shift error, and creep may be found in Handbook 44 (5). The acceptance tolerances in Table 1 apply to new or reconditioned equipment tested within 30 days of being put into service. After that, maintenance tolerances apply they ate twice the values Hsted in Table 1.

The types of systems and problems encountered are reviewed and the ranges of conditions (temperature, pressure, ionic strength) typically approached are considered. The difficulties encountered in making thermodynamic estimates in industrial applications are discussed, with particular reference to the assessment of species and temperature effects, and the estimation of activity coefficients. 

The lower explosive limit and minimum explosive concentrations of flax, wool, cotton, jute, hemp and sisal fibres are of the same order of magnitude as those of highly explosive dusts [15], The explosibility of pyrites dusts with sulfur contents above 20% was evaluated experimentally. Dusts of 30% sulfur content gave explosion pressures of 3 bar at pressure rise rates of 16 bar/sec. Mixtures of 60% pyrites and 40% powdered limestone still showed significant pressure effects, and the proportion of limestone actually needed to suppress explosions was considerably above the values currently accepted by mining industries [16], Effects of mixtures of particle sizes in combustible dusts upon minimum ignition temperature (T ") and upon presence or absence of explosion were studied. Presence of 30% of fines in a coarse dust lowers Tf significantly [17], Experimental explosions of polyethylene,... 

Figure 2.1 presents the simplistic basis upon which all separations are commonly made in our industry. Even membrane separations depend to a large degree upon the vapor pressure and temperature effects shown. A typical temperature dashed line shows how the temperature variance effects a vapor-liquid separation. Notice also the variance for pressure and enthalpy. Inside the phase envelope, the temperature and pressure remain constant while the enthalpy varies. This constant T and P occur in what is called the flash zone. 

Temperature effects on industrial and laboratory strain Wine making [348]... 

The behavior of gases dissolving in water appears to be less complex. The solubility of a gas in water typically decreases with increasing temperature, as shown for several cases in Fig. 17.6. This temperature effect has important environmental implications because of the widespread use of water from lakes and rivers for industrial cooling. After being used as a coolant, the water is returned to its natural source at a higher-than-ambient temperature (thermal pollution has occurred). Because it is warmer, this water contains less than the normal concentration of oxygen and is also less dense it... 

G. Manos, A. Garforth and J. Dwyer Catalytic Degradation of High Density Polyethylene on an Ultrastable Y Zeolite. Nature of Initial Polymer Reactions, Pattern of Formation of Gas and Liquid Products, Temperature Effects. Industrial Engineering Chemistry Research, 39, 1203 (2000). 

Industrially, selectivity is often as important as conversion in considering the efficiency of the reactor. In isothermal reactions, the dilute phase and transition zone may cause better selectivity due to better contact in that region. But in nonisothermal reactions, the effect will be different because of the temperature effect. Mixing of gas and solids in the dilute phase is not sufficient, and this may cause a temperature distribution for exo- or endothermic reactions. 

The LTS-100 results presented here from fhree imporfant industrial applications show encouraging performance in each case. The combination of this good performance and the simple design of the instrument make the LTS-100 promising for cost-effective, nonintrusive industrial temperature sensing. 

In certain industries, single-effect evaporation cannot be used as an economy measure because of the comparatively high temperature maintained in the first effect. In the case of heat-sensitive materials such as concentrated milk products, fruit juices, and pharmaceuticals, it is often necessary to use multiple-effect vacuum evaporators and accept high operation cost in order to preserve the quality of the product. 

Sulfide stress cracking (SSCC) has special importance in the gas and oil industry, as the materials being processed there (natural gas and crude oil) often contain a considerable amount of hydrogen sulfide. SSCC is a low-temperature effect of H2S in an aqueous environment, and sulfidation is the term used for high-temperature (>250°C) sulfur corrosion. In gas pipelines, if the gas is sweet... 

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