ProTreat® software was originally developed for simulating processes for the removal of H2S, CO2, and mercaptans from a variety of high and low pressure gas streams by absorption into thermally regenerable aqueous solutions containing one or more amines. Recently added capabilities include the physical solvent DMPEG (dimethylether of polyethyleneglycol) for acid gas removal, and dehydration using triethylene glycol (TEG). The ProTreat package makes exclusive use of a column model that treats the separation as a mass transfer rate process. This completely eliminates the need for empirical adjustments to simulate new applications correctly. Equilibrium stages and user-supplied estimates of tray efficiencies and HETPs are avoided, and columns are modeled with the number of real trays and physical depth of real packing they actually contain.
ProTreat simulation never requires you to translate theoretical stages or NTU's into actual tray counts or bed depths of real packing. The ProTreat mass transfer rate model deals with real trays and packing right from the outset. It calculates the separation achievable by the specific internals selected for installation in a given tower shell (including swages). Even such details as the number of tray passes is considered.
The ProTreat simulator's mass and heat transfer rate based model for columns applies to both absorbers and regenerators. This can produce substantially different temperatures for the vapor and liquid leaving a tray or a packed segment. It also allows regenerators to be modeled with the same high degree of reliability as absorbers. Because regenerator performance more often than not is decisive in setting contactor performance, the ability to simulate regenerators can be critical to success in revamps, troubleshoots and grass roots designs. Mass and heat transfer rate based modeling is especially valuable in selective treating applications where controlled CO2 slip is wanted. In such applications absorber over-design can be as fatal as under-design. One of the most difficult-to-simulate applications is regenerator off-gas upgrading. ProTreat handles such applications just as easily and naturally as it does conventional absorbers.
The ProTreat package has the full flexibility needed to allow any imaginable flowsheet for amine-based acid gas removal process to be constructed and simulated. From the user's perspective, drawing functionality is similar to Corel Draw. A flexible flow-sheeting capability is needed when simulating processes with the complexity often found in refineries where, for example, multiple contactors at various pressures are supported by one or two common regenerators. In addition to absorbers and regenerators, unit operations blocks include flash tanks, heaters and coolers, cross-exchangers, mixers, dividers, compressors, and turbines.