| 摘要 |
The precipitation of scale-forming salts, such as alkaline earth metal carbonates, sulphates, oxalates, phosphates, fluorides and silicates, in an aqueous system, e.g. on a metal surface in contact with water or brine, is inhibited by adding to the system an amino methyl phosphonate compound of the general formula <FORM:1073888/C6-C7/1> an alkali metal e.g. Na, and n is 1, 2 or 3, the amount of compound added being such that e.g. up to 100 ppm the weight ratio of compound to cation component of scale-forming salts does not exceed 0.5:1. Preferably the compounds used are (CH2)2N2 [CH2PO(OM)2] 4, N [CH2PO(OM)2]3 or (CH2CH2OH)2-NCH2PO(OM)2 where M is H and/or Na. The process is applicable in inhibiting BaSO4 precipitation is water production wells. |
