Cryogenic separation processes reliability

Reliability takes into account the on-stream factors which can cause unscheduled shut-downs. Membrane systems are extremely reliable with respect to the on-stream factor. The membrane separation process is continuous and few control components can cause a shut-down. Typically, the response to unscheduled shut-downs is rapid for GS whereas PSA systems are moderately reliable owing to the numerous valves associated with the process which can cause unexpected shut-downs. The new PSA are designed with alternative modes of operation, in which 100% of design capacity can be achieved while by-passing any failed valve or instrument, with only a slight recovery loss. Failures are automatically detected and by-passed by the microprocessor-based control system. Flowever, stronger and periodic control cycles are required. The cryogenic process is considered by refiners to be less reliable than PSA or membrane... 

Energy efficient gas separation processes, particularly in the chemical and petrochemical industry, have been a subject of increased attention in recent years. This is due to the high energy input, and thus high cost of industrial gas separations by conventional processes, such as cryogenic distillation and/or absorption. Adsorption processes, based on activated carbon or silica gel as adsorbents, have proven reliable, efficient and cost effective for a number of industrial gas separations. The search for a suitable adsorbent is the first step in this [1, 2]. 

---