Humidity storage

Figure 229 shows schematically the discharging of open sorption storages. Humid air blown through the storage becomes dry and can be used for... 

Potatoes cracked. Cause Uneven soil moisture. If soil is alternately dry then wet. roots may split their skins. Prevent problems by keeping soil evenly moist and storage humidity constant. Some cultivars, such as Jeu ell and Puerto Rico 198 , are somewhat resistant to cracking. 

Figure 6-16 Change over time of the amount of water adsorption of alumina powder and borosihcate glass powder under various storage humidity conditions.

Figure 6-17 The relationship between green sheet storage humidity and green sheet...

For dry starch production, the concentrated starch milk is dewatered (vacuum filters or basket centrifuges) and finally dried to storage humidity (12-13%), usually by flash dryers. 

The main advantage of wholesale climate control Hes in easy access to the objects, and the absence of differences in conditions between various spaces within the institution, eg, storage areas, conservation laboratories, and exhibition galleries. The actual values set for the rh are a matter of compromise metals, stone, and ceramics are best served by humidities as low as possible, but organic materials generally require higher values. An accepted... 

Certain grades of siUca gel or selected clay minerals are often used. The buffeting material is preconditioned under the selected relative humidity and, after equihbration, installed in the case. This method of microclimate control has proven to be very efficient, not only in exhibition cases and storage spaces, but also in packing crates used for the transportation of sensitive objects. 

Most emphasis is placed on a program of rigorous preventive maintenance. Appropriate climate conditions can help to prevent mold attack, which typically only occurs at elevated relative humidity. Storage furniture which provides an effective barrier for insects, regular inspection of the collections, monitoring of all collection areas with insect traps, and access control measures which minimize the chance of insect entry into the collection areas, are some aspects of an effective pest control management program (175). 

Shipping and Storage. MaHc acid is shipped in 50-lb, 100-lb, and 25-kg, multiwall paper bags or 100-lb (45.5 kg) fiber dmms. A technical-grade, 50% solution may be shipped in tank cars or tank tmcks. MaHc acid can be stored in dry form without difficulty, although conditions of high humidity and elevated temperatures should be avoided to prevent caking. 

Protection capabilities of bags can be maximized by maintaining the moisture content of the paper at 6—8% by weight, relative to a shipping environment of 21°C at 60% in relative humidity. When the moisture content of shipping-sack paper drops below 6%, the sacks become excessively brittle however, if short-term storage under such conditions is unavoidable, an attempt should be made to place them in an environment with adequate relative humidity for 24—48 hours prior to their use. 

Anhydrous sodium tripolyphosphate is slow to hydrate in contact with the atmosphere under normal ambient conditions and generally remains free-flowing. If the relative humidity is below a critical relative humidity, which is different for both anhydrous forms of STP and dependent on temperature, hydration does not take place. For prolonged storage at room temperature, relative humidities above ca 60% in the air result in water absorption. For shorter periods, high levels of humidity can be tolerated. However, even at higher humidities, the amount of water absorbed is small. The heats evolved from vapor hydration of STP-I and -II have been estimated at 343 and 334 kj /mol (82.0 and 79.9 kcal/mol), respectively (25). 

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