Method and apparatus for achieving higher cooling rates of a gas during bypass cooling in a batch annealing furnace of cold rolling mills

A method for achieving a higher cooling rate of hydrogen during bypass cooling in a batch annealing furnace, the method comprising the steps of:

• filling a preparation unit with water maintained at ambient condition;
• measuring in a first measuring and control device nanoparticles including dispersants at a lot-size determined based on steel coils to be cooled, the first device controlling flow rates, pressure, and temperature of the nanofluid to be supplied to a heat exchanger;
• mixing the nanoparticles including the dispersants with the water at a volumetric ratio of 0.01-5% in the preparation unit;
• supplying the nanofluids from the preparation unit to a reservoir by using a pump;
• delivering hydrogen gas to the heat exchanger at a heated temperature;
• delivering the nanofluid at a predetermined flow-rate, temperature, and pressure from the reservoir to the heat exchanger;
• supplying cooled hydrogen gas from the heat exchanger to the furnace for cooling heated steel coils;
• returning hydrogen to the heat exchanger from the furnace;
• and
• using the nanofluid delivered to the heat exchanger for exchanging heat with the hydrogen;
• wherein, the nanofluid exits the heat exchanger via a first outlet, the cooled hydrogen exits the heat exchanger via a second outlet, and the hydrogen is cooled at a higher rate.