Water ingress

In the United Kingdom there are approximately 2000 active landfiU sites with an aimual combined water ingress of 40 x 106 (48,49). The... 

Surface preparation of the core foil was originally simple acid etching. As the importance of durable surface treatments became known, a more stable chemical conversion coating with an organic primer-like coating became standard. Still, water ingression into honeycomb structure continued to cause the occasional... 

Where acid process contaminant or acidic water ingress occurs, the bulk BW pH may quickly drop as low as 5.0. This may occur, for example, where there is only limited alkaline buffering of BW because of low cycles of concentration and/or high-purity FW. Where acidic incursions occur, a general thinning of the boiler tubes, drums, and shell rapidly takes place, giving rise to a clearly visible irregular surface. 

Fig. 2.3.11 Left the ingress of a hydrophobic silane coating into building sandstone. Right subsequent water ingress and pumping through a treated surface.

The measurement applications of density weighted drying profiles, water ingress, water phase transitions, crack detection, chlorine, sodium and lithium imaging applied to cement-based materials can be easily translated to other porous media. Density weighted MRI will no doubt prove to be a powerful tool in material science research. 

All equipment should be designed and constructed in a manner that prevents the retention of moisture (unless it is designed to deliberately stay full of sterile water), ingress and harbourage of vermin and soil and to facilitate inspection, servicing, maintenance and cleaning. 

Kaltenecker-Commercon JM (1992) Water ingression into poly(imide siloxane)s. PhD dissertation. Virginia Polytechnic Institute and State University, Blacksburg... 

Intruding water, ingress of acid vapors, and process spills are some of the menaces that encourage corrosion problems on insulated equipment. Very few, if any, thermal insulation systems are completely waterproof, and the steel or alloy material covered by insulation is... 

The Safer Piping module sums up the corrosion on piping under insulation as a problem of water ingress on piping with poor surface protection. Engineering, construction, and maintenance recommendations parallel those presented in the heading Corrosion under Insulation offered earlier in the chapter. 

The water ingress properties of various polymers can be assessed by values of their permeability coefficient and the diffusion constant of water (Table 15.13). The permeability coefficient is defined as the amount of vapor at standard conditions permeating a sample that is 1 cm2 and 1-cm thickness within 1 s with a pressure difference of 1 cmHg across the polymer. The diffusion coefficient is a measure of the ease with which a water molecule can travel within a polymer. There is a wide variation in the maximum amount of water absorbed by polymeric materials. Certain systems have very low absorption at lower temperatures, but the rate of absorption increases significantly at higher temperatures. 

Hazardous features to be considered will include pressure relief handling of hazardous materials such as acids and alkalis protection from steam and other high-temperature fluids and electrical classification for handling solvents or protection from water ingress, high speed rotating machinery, and noise levels. 

The specification for bioseparation equipment will depend on its location, for both mechanical and electrical components. The need to weatherproof a piece of equipment and protect it from rain, wind, and temperature extremes will require specific provision to be made. Equipment located indoors will not necessarily require such features, although cleaning down of plant areas with hoses, as is common in the food industry, requires some degree of protection against water ingress for electrical items such as motor drives, control panels, and instruments. 

The initial inspection shall ensure that the type of protection of the apparatus and its installation are appropriate. As a rule, initial inspections shall be detailed inspections. Periodic inspections are of the visual or close type. They shall detect all the factors effecting the deterioration of apparatus, e.g. corrosion, exposure to chemicals or solvents, accumulation of dust or dirt, water ingress, exposure to excessive ambient temperature, mechanical damage, unauthorized modifications or adjustments and inappropriate maintenance. 

The risk of water ingress into eventual pores and cavities in frozen coolant inside SRUs and thus an increase in reactivity up to initiation of spontaneous chain reaction must not be ruled out ... 

Refined calculated-experimental investigations of the effects of potential water ingress inside the SRU-storing volume are necessary ... 

Under the used technology of SRU temporary storage the probability of water ingress into the container storing SRU must not be ruled out the risk of initiating spontaneous chain reaction will exist until every SRU is dismantled ... 

Nuclear and Radiation Safety in Case of Water Ingress into Reactor Core of KM-1 Stand... 

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