China Salt Drying Hot Air Heater Factory & Service

Direct combustion passes combustion flue gas containing carbon soot, sulfur oxides (SOx), and heavy trace hydrocarbons directly through the salt bed. In edible salt, this violates international food hygiene laws (Codex Standard 150-1985). In chlor-alkali production, carbon black and sulfates foul the ion-exchange membrane cells, causing irreversible voltage drops and premature cell replacement. Ruitu's indirect hot air heaters pass flue gas through sealed heat exchange tube bundles, guaranteeing that only 100% clean, uncontaminated heated air comes into direct contact with the salt crystals.

Standard carbon steel and basic 304 stainless steel rapidly succumb to pitting and chloride stress corrosion cracking (SCC) in hot salt environments. Ruitu utilizes high-temperature, corrosion-resistant austenitic stainless alloys such as SUS310S, 253MA, and Incoloy 800H for heat exchanger fire tubes. For wet-end transitions and air dampers, carbon steel hulls lined with compressed PTFE (polytetrafluoroethylene) or PO (polyolefin) are implemented to isolate hot acidic halide vapors from pressure-bearing structures.

Our combustion chambers are engineered with multi-fuel versatility. Depending on local client utility economics, our systems can be configured with dual-fuel modulating burners capable of firing Natural Gas (LNG/CNG), Light Diesel Oil, Heavy Fuel Oil (HFO), Propane/LPG, or solid biomass pellets and pulverized coal using dedicated cyclonic furnace chambers.

A standard 10 to 50 TPH turnkey salt washing and drying line typically follows a 16-to-22-week project cadence: Weeks 1–3 comprise raw material lab testing and thermal balance engineering; Weeks 4–12 encompass workshop fabrication of hot air furnaces, crushers, conveyors, and lined valves in Weifang; Weeks 13–16 cover export crating and sea freight delivery; and Weeks 17–22 consist of on-site mechanical alignment, electrical hook-up, refractory dry-out, and continuous-run load testing under Ruitu engineers' supervision.

We employ computational fluid dynamics (CFD) modeling to design hot air distribution plenums, ensuring balanced dynamic pressure across the entire drying deck. Coupled with fast-response PID temperature loops driving proportional burner actuators, air temperature is controlled within ±1.5°C of setpoint. Waste heat economizers further recycle residual flue enthalpy into intake air, ensuring fuel-to-air thermal conversion efficiencies consistently exceed 85% to 90%.