Shell and Tube Condenser

Tube-in-tube condenser structure
The tube-type condenser is mainly composed of the outer shell, tube plate (also known as the header), tube bundle, and top cover (also known as the head). Parallel tube bundles are installed inside the circular shell, with the ends of the tubes fixed on the tube plate. The tubes are generally fixed to the tube plate using welding or expansion methods. The top cover, equipped with import or export tubes, is connected to the outer shell flanges at both ends with screws, forming a fluid distribution chamber between the top cover and the tube plate. It is widely used due to its simple and sturdy structure, ease of manufacturing, broad material range, high processing capacity, and strong adaptability.
During heat exchange, cooling water enters through the connection pipes at the top cover, flows within the pipes, and this path is known as the tube side; harmful vapor flows through the gap between the tube bundle and the shell, and this path is called the shell side; the surface area of the tube bundle is the heat transfer area. In condensation recovery, whether it is the condensation of saturated vapor or the condensation containing non-condensable gases, generally, condensation occurs in the shell side of the horizontal condenser due to its合理性 in terms of heat transfer, pressure drop, and cleaning.

Tube-type Condenser Categories
(1) Fixed Tube Sheet Heat Exchanger: Simple and compact structure, capable of withstanding high pressure, cost-effective, easy to clean in the tube side, and easy to plug or replace the tubes when damaged.
(2) Floating Head Heat Exchangers: Easy to clean inside and between tubes, and do not produce thermal stress.
(3) U-tube Heat Exchanger: Consists of a single tube plate with the tube bundle made up of multiple U-shaped tubes. Both ends of the tubes are fixed on the same tube plate, allowing for free expansion and contraction. No thermal stress is generated when there is a temperature difference between the shell and the U-tube heat exchanger.
(4) Sliding header plate heat exchanger: Simple structure, low cost, and can add baffles in the tube box as needed to enhance heat transfer.

Features of Tube-in-Tube Condensers
(1) Horizontal shell-side condensing film heat transfer coefficient is several times higher than that of vertical tube inner or outer film, and non-condensables do not accumulate in dead corners, making them easier to be discharged.
(2) The cooling water flows through the pipes, which facilitates the cleaning of scale. Water flow inside the pipes ensures a higher velocity, which is beneficial for reducing the rate of scale formation and improving the heat transfer coefficient of the water film.
(3) Tube-in-tube condensers are used to position the lower tubes at the cooling water inlet, allowing condensate to accumulate at the bottom for temperature reduction. In surface condensation systems, it's crucial to further cool the condensate. If the condensation system temperature is high, organic gases will volatilize significantly upon contact with air. The outlet temperature of the condensate is typically required to be 60℃ or lower. Of course, an additional cooler can be added, but this will increase costs.