Application of ASTM B338 Gr.2 Condenser Tubes in PTA production

What is PTA?

Purified terephthalic acid (PTA) is an important organic compound with the chemical formula C₈H₆O₄. It is the refined product of terephthalic acid (a white crystalline solid) and typically exists in the form of colorless crystals or white powder. PTA is a significant industrial chemical, primarily used in the synthesis of polyethylene terephthalate (PET), which is a polyester resin widely employed in textiles, food packaging, fibers, and other plastic products.

A construction site for a PTA project , featuring core equipment such as condensers made of ASTM B338 titanium Gr.2 tube bundles, reactors, and distillation towers.

The use of Ti Gr.2 tubes in the PTA project

In the oxidation reaction unit of purified terephthalic acid (PTA) production facilities, the first-stage condenser in the reactor plays a crucial role. This condenser is utilized to cool the steam and unreacted substances in the outlet gas from the reactor, condensing them into liquid form for further processing or recovery. Typically, the heat exchange tube bundle of this condenser is made of ASTM B338 Grade 2 titanium tubes. The medium flowing through the condenser is an acetic acid solution containing bromide ions, with a working temperature of up to 190°C.

ASTM B338 titanium condenser tubes in PTA project, 19mm(O.D.) x 2.6mm(W.T.) x 10800mm(L), supplied to Amsterdam, Netherland.

The widespread use of ASTM B338 Grade 2 titanium condenser tubes in PTA production is based on several key reasons:

Corrosion resistance: The operating environment of the oxidation reaction unit’s first-stage condenser often involves high temperatures, pressures, and corrosive media such as hot reaction gases and cooling media containing acidic substances. Titanium exhibits excellent corrosion resistance, capable of withstanding these harsh operating conditions, ensuring long-term stable operation of the equipment.

Thermal conductivity: Titanium condenser tubes possess good thermal conductivity, facilitating the effective transfer of heat from the outlet gases of the reactor to the cooling medium, thereby achieving the cooling of the reaction system. This helps in controlling the reaction temperature, improving reaction efficiency, and stability.

High strength-to-weight ratio: Titanium has high strength and a lightweight, making titanium condenser tubes more convenient during installation and maintenance. Additionally, the lightweight characteristics of titanium contribute to reducing the weight load of equipment, lowering transportation and installation costs.