Effect of initial moisture

Demirbas, A., Effect of initial moisture content on the yields of oily products from pyrolysis of biomass. Journal of Analytical and Applied Pyrolysis 2004, 71(2), 803-815. 

Little previous work has focused directly on the impact of water content on the formation of pyrazines. Koehler and Odell (19) specifically chose a solvent system of lower water content for their stutfy Maga and Sizer (2Q) investigated the effects of initial moisture content and temperature of extrusion on the formation of pyrazines in potato flakes. 

Fig. 9. Effect of initial moisture and humidity on drying time.

Figure 28.9 shows the effects of initial moisture content and air circulation on the energy consumption of a typical fluidized-bed dryer. The results presented were collected from commercial continuous dryers with capacities of 5-10 tons/h operating at the drying temperatures of 120°C-150°C and superficial air velocities of 2.8-3.25 m/s. ... 

FIGURE 28.9 Effects of initial moisture content and air recirculation on thermal energy consumption of a fluidized-bed dryer. (From Prachayawarakorn, S. et al., J. Stored Products Res., 41, 479, 2005.)... 

Fig. 3. Effect of feed moisture content on energy available for synfuel production. Assumes feed has a heating value of 11.63 MJ /kg (5000 Btu/lb) dry. A, 0% moisture in dried feed B, 30% moisture in dried feed. For example, reduction of an initial moisture content of 70 wt % by thermal drying to 30% moisture content requites the equivalent of 37% feed energy content and leaves 63% feed energy available for SNG production.

Another aspect to consider in the design of closed-drying systems is the drydown time. The drydown time is the period requited for the system to dry down from its initial water concentration (or partial pressure) to a concentration that approaches equihbrium with the desiccant. During this time, the system is not fljlly protected from the negative effects of the moisture that the desiccant is designed to remove. In such a system, the instantaneous drying rate is proportional to the water content at any time (18). 

Soil Moisture Effect The effects of soil moisture content and soil texture and pore size distribution on kerosene conductivity were studied by Gerstl et al. (1994). Figure 12.13B shows the kerosene conductivity in sand, loam, and clay soil columns, as the initial moisture content varies from 0% (oven dried) to field capacity. 

Yencho then constructed the initial version of the machine and explored the parameters necessary to successfully form flaw-free parts. A key finding concerned the effects of trapped moisture. Despite the generally hydrophobic nature of PEEK, it was found that small amounts of moisture absorbed by the Gr/PEEK laminates subsequent to their manufacture converted into steam during the forming operation and caused extensive delamination. This was in... 

Effects of Free Moisture. Availability of free moisture after host inoculation with a foliar, epiphytic bioherbicide is critical to the initiation of the infection process. Experiments on free moisture (dew) interactions with other environmental parameters and the host-pathogen system are usually conducted in temperature-controlled dew chambers. This type chamber is constructed such that the plant radiates energy to a heat sink which is the temperature-controlled wall of the chamber. The humid air in the chamber is also temperature controlled, and dew forms on the plant... 

Rather, the setting reaction is entirely an addition polymerization process, generally photo-initiated, and involving free radicals. Once the material is set, it is able to absorb trace amounts of moisture, and this allows the acid-functional groups to manifest their acidity by dissociating after which they attack the basic glass to form a small amount of salt matrix [1 ]. The effect of this moisture-initiated reaction is discussed in later sections of this chapter. 

Figure 7. Effect of initial pH of the substrate on xylanase production by Aspergillus oryzae NRRL 3485. Norhoptimized wetting solution consisted of (g/l) NH4NO3, 5 com steep liqwn (50 % dry weight), 2 KH O, 5 NaCl, / MgS04 1 trace element solutim I and II, I ml/L Optimted wetting solution consisted cf (g/l) corn steep liquor (50 % dry yreigld), 75 KH 04, 5 NaCl, I M S 4,1 t ace dement solution I arid II, I mVl (T, 30X mitiai moisture corttent, 83% , initial pH, 8.3, fermentation time, 4 d).

Moreover, the effect of air moisture content can be evaluated as shown in Fig. 7. When the moisture content is high, the initial temperature rise of the fabric also becomes high. This may be because the saturation temperature in the initial stage largely depends on the air moisture content. 

A high moisture content will also substantially reduce the rate of diffusion of carbon dioxide and, hence, the rate of carbon-ation of the concrete. An important effect of the moisture content of concrete is its effect on the electrical resistivity of the concrete. Progressive drying of initially water-saturated concrete results in the electrical resistivity increasing, and steel corrosion would be negligible even in the presence of chloride ions, oxygen and moisture. 

The effectiveness of phenoHc inhibitors is dependent on the presence of oxygen and the monomers must be stored under air rather than an inert atmosphere. Temperatures must be kept low to minimise formation of peroxides and other products. Moisture may cause mst-initiated polymerization. 

Insoluble corrosion prodiic ts may be completely impeivious to the corroding liquid and, therefore, completely protective or they may be quite permeable and allow local or general corrosion to proceed unhindered. Films that are nonuniform or discontinuous may tend to localize corrosion in particular areas or to induce accelerated corrosion at certain points by initiating electrolytic effects of the concentration-cell type. Films may tend to retain or absorb moisture and thus, by delaying the time of drying, increase the extent of corrosion resulting from exposure to the atmosphere or to corrosive vapors. 

In our study, the effect of moisture over the nonneutral pH range of 3-11, direct sunlight, ozone at a concentration level of 6000 ppm, and the effects of loading stresses, were investigated for the three commercial sealants. A characteristic variation of crosslink density for the typical silicone sealants is shown in Fig. 29. This figure depicts the results for the coupons exposed to moisture and sunlight. Initially upon exposure, the crosslink density of the sealants exhibit an increase due to the availability of residual uncurred crosslink sites... 

The electrical resistance of a coating on a pipeline will depend upon the effectiveness of its initial application to the metal and on its condition at the time of testing absorption of moisture may decrease the resistance by as little as 10% during a 2y-year period. The leakage resistance of a given section of pipeline can be determined by the following procedure ... 

Chemical parameters (e.g., partition coefficients, decay rates, temperature and moisture effects) are not usually considered as calibration parameters because they can be measured in a laboratory moreover, calibration is usually not possible due to lack of observed data. However, most scientists will agree that extrapolation of laboratory parameter measurements to field conditions is a risky assumption. If observed chemical data are available, refinement of initial chemical parameters through calibration should be considered. Errors in calibration-derived parameter values are often a function of how much calibration was performed or errors in system inputs and/or outputs. In many modeling efforts, conscientious model users will often overrun the calibration budget because of the natural tendency to continue to make calibration runs in an effort to minimize discrepancies between simulated and observed values. Parameter errors associated with calibration are more often a result of missing and/or erroneous data either as system inputs or outputs. 

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