The invention relates to a so-called zero emission ‘AST-CNR/ITM system’ modular plant for removal of pollutants from flue gases produced by industrial processes. The plant comprises prefabricated modular elements with programmed and automatic operation, easy to mount and assemble on site without undergoing expensive plant stoppage. Each module or ‘reaction tower’ comprises a plurality of sections vertically arranged on top of one another, which carry out the following functions: Removal of particulate matter with treatment and removal of chemical pollutants, such as heavy metals, chlorides, fluorides Treatment and removal of SOx Treatment and removal of NOx Capture of CO2 Production of hydrogen Production of methanol. The various sections may be combined according to the requirements of the plant and of the flue gases to be treated.