This is KDP semi-welded plate heat exchanger in a chlor-alkali industrial plant, also called a chlorine cooler (titanium semi-welded heat exchanger). The plates of the heat exchanger are imported titanium, and the chlorine channels are welded with titanium, which is corrosion-resistant and leak-proof. The cooling water side can be opened for cleaning to avoid leakage of highly toxic gases and extend the life of the equipment. This "one-side welding + one-side detachable" design achieves the best balance between safety, maintainability and cost, and is an ideal choice for chemical process optimization.