System for coating heat transfer tube for condenser
A system for coating a heat transfer tube for a condenser is disclosed. The system simplifies a process of coating the heat transfer tube, and is able to uniformly coat a plurality of heat transfer tubes. In addition, the system is economically feasible in that coating solution can be reused by collecting and circulating it. Due to super-hydrophobic coating, the size of a droplet condensed on the surfaces of the heat transfer tubes coated by the system can be reduced, and a condensation heat transfer coefficient can be increased.
1. A system for coating a plurality of heat transfer tubes, the system comprising:
first and second rotating units configured to support and rotate a cylindrical bundle in which the plurality of heat transfer tubes are arranged;
a spray unit facing a circumference of the cylindrical bundle and configured to supply a coating solution to the plurality of heat transfer tubes of the cylindrical bundle;
one or more spray nozzle units coupled to the spray unit and configured to coat respective surfaces of the plurality of heat transfer tubes with the coating solution;
a recovery unit configured to collect a remaining coating solution after the coating solution is sprayed from the one or more spray nozzle units to coat the respective surfaces of the plurality of heat transfer tubes; and
a circulation unit coupled with the recovery unit and the spray unit and configured to supply the remaining coating solution collected in the recovery unit to the spray unit.
2. The system according to claim 1 , wherein the circulation unit comprises:
a first connection pipe coupled to the recovery unit;
a second connection pipe coupled to the spray unit; and
a circulation pump configured to circulate the remaining coating solution at a predetermined pressure,
wherein the circulation pump is coupled with the first connection pipe and the second connection pipe.
3. The system according to claim 1 , wherein the spray unit is provided in a form of a linear bar configured in a longitudinal direction of the cylindrical bundle.
4. The system according to claim 3 , wherein the spray unit moves in a horizontal direction parallel to the cylindrical bundle so as to coat the cylindrical bundle.
5. The system according to claim 4 , wherein the horizontal movement of the spray unit is performed by a moving unit.
6. The system according to claim 1 , wherein the coating solution includes a silane compound and an organic solvent.
7. The system according to claim 6 , wherein the coating solution includes the silane compound and the organic solvent at a weight ratio of 1:900 to 1:1100.
8. The system according to claim 6 , wherein the silane compound includes at least one compound selected from a group consisting of perfluorodecyltrimethoxysilane, triethoxyoctylsilane, perfluorodecyltrichlorosilane, and perfluorodecyltriethoxysilane.
9. The system according to claim 6 , wherein the organic solvent includes at least one compound selected from a group consisting of methanol, ethanol, propanol, hexane, heptane, and cyclohexane.
10. The system according to claim 1 , wherein coating solution is sprayed from the spray nozzle units at a pressure ranging from 0.1 bar to 0.7 bar.