METHOD FOR PRODUCTION OF HOLLOW MICROSPHERES IN SPRAY-DRYING PLANT Russian patent published in 2002 - IPC

FIELD: production of hollow microspheres on the basis of liquid resol phenol-formaldehyde resins used for protection of environment as a means for gathering of petroleum and petroleum products at their spread in basins, for facilitation of the process of drilling of oil and gas wells, as well as a filler. SUBSTANCE: hollow microspheres are produced in a spray-drying chamber with a means for spraying installed in it by spraying of a heated liquid compound comprising resol phenol-formaldehyde resin, blowing agent, surfactant and water in the form of a flow of drops into a flow of heated gas having a temperature at which simultaneous proceeding in drops of the processes of hardening of phenol-formaldehyde resin and decomposition of blowing agent with liberation of gas, subsequent inflation, hardening and drying of drops is going on. Use is made of a spray-drying plant containing a spray-drying chamber and a means for spraying in the form of an air-atomizing burner or a centrifugal disk sprayer, in which the flow of atomized drops and the flow of heated gas are fed coaxially to the spray-drying chamber in parallel with each other practically over the entire height of the spray-drying chamber in the condition of uniflow laminar flow until the drops would be blown and hardened to a free-flowing state, and hollow microspheres are continuously extracted with the gas flow from the spray-drying chamber, the relation between the working volume of the spray-drying chamber and the volume hourly output of the hollow microspheres is selected within 25 to 250 /m³•h^-1. EFFECT: enhanced operating indices of the process. 2 cl, 1 dwg, 2 tbl, 1 ex