This test method covers the determination of carbonate (CaCO3) content of soils and soft rock which can be readily broken down by mechanical effort. It is a gasometric method that utilises a simple portable apparatus.
The test method is quickly performed for soils containing calcium carbonate.
The calcium carbonate content of soil is determined by treating a 1-g dried soil specimen with hydrochloric acid (HCl) in an enclosed reactor vessel. Carbon dioxide gas is evolved during the reaction between the acid and carbonate fraction of the specimen. This pressure is measured with a bourdon tube pressure gauge that is precalibrated with reagent grade calcium carbonate.
This test method is used to determine the presence and quantity of calcium carbonate on a marine soil specimen. Calcium carbonates k known cementing agents, are water soluble at PH<7, and are soft on the Mohs' scale compared to other soil minerals.
The acrylic chamber is 63.5mm internal diameter x 139.7mm long and sealed with anodised end caps. The unit comes complete with 10psi test gauge, bleed valve and a 20ml cup with handle.
Please refer to ASTM D-4373 for complete instructions on how to prepare and perform the test for determining the carbonate content of soils and soft rock.
The device is made from Stainless Steel with an acrylic chamber. The pressure gauge can be damaged if the solution is allowed to flow into the gauge opening. Keep in mind that when tilting to spill the acid, that care must be taken to prevent this acid from reaching into the pressure gauge opening. Clean the device thoroughly after use.