Selection of pipes for liquid chlorine and cyanogen chloride

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I urge all experts to share their insights: I’m not sure which medium to choose among the several options available; please help me make a decision. 1. Liquid chlorine: to be transported at 25°C (under an operating pressure of 1.5 MPa), with the pipes insulated for heat protection. Liquid chlorine is commonly transported at low temperatures; 16MnD steel is used for the pipelines. According to corrosion manuals, carbon steel can be used only at 25°C and not at 50°C, so it’s unclear what material would be suitable in this case. 2. Process gas: Low pressure, high temperature (380°C); mainly cyanuric chloride gas, with an additional amount of Cl2 at 10 kg/h ； CO2: 3.5kg/h ； CNCl: small amount ； H2O ＜1kg/h ； This medium is characterized by high temperatures, extreme toxicity, and chlorine-induced corrosion. It is not clear whether M400 or IN600 should be used, or if some other more suitable material would be better. 3. Exhaust gas: low pressure, temperature of 250°C; the main component is air, with small amounts of Cl2 present as well ； CNCl: small amount ； A small amount of H2O ； This medium is highly toxic and corrosive by chlorine; it’s not clear whether 304L or some other more suitable material should be used. 4. Cyanogen chloride gas: At low pressure and a temperature of 250°C, it might be possible to use 316L, given that its properties are similar to those of hydrogen chloride. 5. For waste gases and liquids with moderate temperatures (below 140°C) whose main components are Cl2, CNCl, HCN, HCl, NH4Cl, HCl, and H2O, the composition is complex, involving both corrosive effects and high toxicity. It is considered appropriate to increase the pressure rating to PN25 and use PTFE-lined pipes; in this case, soft gaskets would be required. According to GB50316, soft gaskets must be used for highly toxic media, and flanges with male and female threads are required. However, it seems that flanges with such threading cannot be manufactured for lining purposes, so it’s not clear what to do.