Industrial Scale Propylene/Propane Separation Using Pressure Vacuum Swing Adsorption

Abstract

Conventional propylene/propane separation via distillation is capital- and energy-intensive. Pressure vacuum swing adsorption (PVSA) is a potential low-cost alternative to C3 distillation. In this work, a new 7-step PVSA cycle is developed using 4A zeolite as the adsorbent, capable of separating 84.4/15.6 propylene/propane (wt %) mixture to produce high purity (>99.5 wt %), high recovery (>99%) propylene at a low energy consumption. The proposed PVSA unit is simulated and costed together with its peripheral units using industrially relevant feed condition and product specifications. The lost opportunity cost arising from the presence of propylene in the raffinate product is also included in the costing algorithm. The proposed PVSA unit is optimized using a global stochastic optimizer, giving a minimum total cost of US$20.86 per tonne of propylene. This is significantly lower than the cost of an equivalent distillation unit, which is found to be US$41.07 per tonne of propylene. The use of PVSA for propylene/propane separation can thus lead to a significant improvement in profitability. The net present value (NPV) of PVSA over distillation for a 450 KTA propylene plant is found to be US$76.79M.

Balancing the Grain Boundary Structure and the Framework Flexibility through Bimetallic Metal–Organic Framework (MOF) Membranes for Gas Separation

“…P ropylene (C 3 H 6 ) is one of the most important raw materials to manufacture plastics, and the purity determines its end use. 1,2 Purification of propylene in industry is accomplished by removing propylene from the propylene/ propane (C 3 H 6 /C 3 H 8 ) mixture via energy-intensive cryogenic distillation. 2,3 Accordingly, developing the energy-saving and eco-friendly membrane-based separation technology is greatly impactful.…”

“…Propylene (C 3 H 6 ) is one of the most important raw materials to manufacture plastics, and the purity determines its end use. , Purification of propylene in industry is accomplished by removing propylene from the propylene/propane (C 3 H 6 /C 3 H 8 ) mixture via energy-intensive cryogenic distillation. , Accordingly, developing the energy-saving and eco-friendly membrane-based separation technology is greatly impactful . Among all kinds of membranes, molecular sieving membranes can selectively separate two different species according to their size and shape, but one of the challenges is to select a proper material with suitable sieving apertures .…”

Enriching Propane/Propylene Mixture by Selective Propylene Hydroformylation: Economic and Environmental Impact Analyses

“…Several alternative techniques have been recently proposed to reduce the energy intensity of C3-splitters, including extractive distillation, 37 membrane separation, 38 adsorption, 39 and hybrid designs that combine different separation technologies like hybrid membrane distillation 40 and hybrid distillation−pervaporation schemes. 41 For instance, pressure vacuum swing adsorption technology is reported to reduce capital costs by 58.1% and operating costs by 49.2%, 42 while vapor recompression and self-heat technology is reported to reduce capital cost by 54.6% and operating cost by 54.7%. 43 Despite these advances, conventional distillation remains the primary method by which propylene and propane are currently separated in industry.…”

An initial evaluation of the thermodynamic or kinetic separation performance of cation-exchanged LTA zeolites for mixtures of propane and propylene

“…Such adsorption based-installations, in which the main part is the design of an efficient adsorbent [15], stand out as the most attractive techniques, simply because of possible high selectivities and high capacities towards propylene obtained under mild operating conditions (ambient temperature and atmospheric pressure, and even in low partial pressure domain). Thereby, compared with distillation, adsorptive separations using adequate porous materials tends to be an energy-and a cost-effective strategy [11,16,17].…”