Organic additives for dispersion stabilisation a rich nutrient basis

2 Organic additives for dispersion stabilisation - a rich nutrient basis 

To be able to produce a suspension having a controlled solids content, often of more than 70w/w%, special dispersants are required. Without such dispersants, a mixture containing a mineral, such as calcium carbonate, with only 30w/w% water is no longer flowable. Pigment and filler producers have developed highly active polymer systems, especially for the use of mineral slurries in the paper industry, which allow such concentrations to be achieved without destroying the complex chemistry of a paper machine. 

The dispersants, usually based today on salts of polyacrylic acid (PAA), represent a rich supply of organic nutrients for cells. They serve also as both a carbon and energy source. Mineral dispersions, however, also 

The microbiological colonies, as well as their growth in a mineral dispersion, can be influenced by many different factors, such as  

Higher salt concentrations lead to a differential osmotic pressure across the microbial cell walls. The effects are selective to the species present in a system. Usually it is a change in salt concentrations, rather than an absolute level, that can have an inhibiting effect on the growth of microorganisms already extant in the system. 

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