Rock wool

Rock wool, frequently referred to as mineral fiber, is made from non virgin siUceous materials and is formed in a similar manner to that of fiber glass. Refractory fibers (qv), also formed in a similar manner, are available for high temperature appHcations. 

Insulation. Impure sdiceous limestone and blast-furnace slag are the main raw materials for making rock-wool insulation bats and peUets (see Insulation, thermal). 

Recommended Thickness of Insulation Indoor insulation thickness appears in Table II-2I, and outdoor thickness appears in Table 11-22. These selections were based upon calcium silicate insulation with a suitable aluminum jacket. However, the variation in thickness for fiberglass, cellular glass, and rockwool is minimal. Fiberglass is available for maximum temperatures of 260, 343, and 454°C ( 500, 650, and 850°F). Rock wool, cellular glass, and calcium sihcate are used up to 649°C (I200°F). 

Rock wool A mineral wool produced from naturally occurring igneous rock. 

From these it can be seen that rock wool, slag wool and glass wool are all mineral wools. 

Rock wool special products can be used up to 1100°C, but generally a maximum operating temperature of 850°C is recommended. Like glass wool, the lower density products used in buildings and H V applications have recommended limits of 230°C. 

Fill the existing wall cavity with a suitable insulant such as fiberglass, rock wool, polystyrene beads or foam. The greater the thickness of the cavity, the lower the CZ-value. 

Continuous filament glass fibres Respirable Inhalable Glass wool fibres Rock wool fibres Stag wool fibres Special purpose glass fibres Talc (containing no asbestos fibres)... 

Technical advantage/function Basalt rock wool is used for noise insulation in automotive exhaust units for the purposes of noise absorption. Vital technical requirements are temperature resistance, noise absorption behaviour, corrosion resistance and mechanical stability. Now textile continuous glass fibres and biosoluble mineral wools are also used for this application in exhaust units. 

Environment and health-related problems In prodnction and processing (packaging, installation of basalt rock wools) fibre dnst is released. This dnst may canse skin and respiratory diseases. Basalt rock wools are biopersistent mineral wools and, as snch, have a certain carcinogenic potential. Conversely, textile continnons glass fibres are not considered to be carcinogenic dne to their stmctnre (fibre diameter = 24 pm) and biosolnble mineral wools dne to their solnbility in the Inng. 

Direction of innovation (from the standpoint of market actors - 6a) A complex assessment situation (classification, criteria for restriction of liability, transitional regulations ) resulted in confusion with regard to the need for substitution for manufacturers and users of basalt rock wools. 

Direction of innovation (from the standpoint of the SubChem research group - 6b) If biopersistent basalt rock wools are replaced by biosolnble mineral fibres (in manufacture, processing, recycling), the internal exposure that causes cancer is reduced. This makes a significant contribution to occupational health and safety. 

Up until approximately 1998 almost 100 % of fiUing materials used in silencers still comprised basalt rock wools. 

Index Entries Vitamin B12 methane acclimated methanogens trace metal ions rock wool. 

A schematic of the experimental system is shown in Fig. 1. One liter of culture liquid was added to a 2.8-L cylindrical glass column reactor, and 300 mL of cylindrical carrier was packed with rock wool. All of the tubing connections, stoppers, and seals in the column were made of butyl rubber. To prevent photodecomposition of vitamin B12, the outside of the whole device was covered with a vinyl sheet to shut out light. The digestion was carried out at 55°C and 20 d of hydraulic retention time (HRT). 

Fig. 1. Schematic of batch fermentation system with rock wool carrier.

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