Polymer soil stabilization with cement production, which can be as high as 1.25 tons of carbon dioxide per ton of cement. Polymer treatments modify the size, shape, and cohesion of soil aggregates by changing the interactions between soil particles. Because polymer-soil interactions occur on the surfaces of soil particles, the amount of surface area in the soil (in other words, its dominant particle size) is of great importance. Polymers have only weak interactions with the large sand- and silt-sized particles of soil, while they bond directly to finer clays. Although polymers mainly interact with the clay fraction of soils, they do change the
Sand filter solid-liquid separation such as settling tanks, self-cleaning screen filters, hydrocyclones and centrifuges. There are several kinds of depth filter, some employing fibrous material and others employing granular materials. Sand bed filters are an example of a granular loose media depth filter. They are usually used to separate small amounts (<10 parts per million or <10 g per cubic metre) of fine solids (<100 micrometres) from aqueous solutions. In addition, they are usually used to purify the fluid rather than capture the solids as a valuable material. Therefore they find most of their uses in liquid effluent (wastewater) treatment. Sand bed