Random packing is one of the 3 primary devices used in mass and heat transfer applications (the other 2 devices are structured packing and trays.) Like the other 2 devices, the primary purpose of random packing is to create surface area for vapor/liquid contact so that thermodynamics can produce desired chemical separation. Chemical separation includes distillation, absorption and stripping.
In most chemical separation (aka mass transfer) processes, vapor is driven upward in the column by heat and pressure while liquid falls downward in the column under the force of gravity. There are 3 primary components in the selection of a random packing (or any other mass transfer device) and they are capacity/pressure drop, efficiency and dollars. The larger the random packing, the higher the capacity, but at a cost of lower efficiency. The smaller the packing, the higher the efficiency but at a cost of lower capacity and higher financial cost. The design engineer must select the appropriate packing that provides the most economical balance between capacity and efficiency.
This first generation of random packing is characterized as having the same height as its diameter. Since the Raschig Ring Packing has relatively low capacity, low efficiency and high costs, its applications are generally limited to corrosive or extremely high temperature applications where the material of construction is ceramic or carbon/graphite.
The greatest single improvement in random packing came with the introduction of “windows” and “finger” to the Raschig Ring packing. By opening up the Raschig Ring, by punching tabs in the wall of the ring to created internal drip points within the ring, both the capacity and efficiency of the random packing increased by 50-80% over the Raschig Ring Packing. The Pall Ring is characterized by having the same height as its diameter. This type of packing is used extensively in absorption, stripping and distillation services. ASRP High Performance Packing can replace it for better efficiency and capacity in the same bed height and column diameter.
The next generation of random packing was accomplished with the development low aspect ratio packing. The “low aspect ratio” refers to the height of the packing being less than the nominal diameter of the packing. The low aspect ratio packing promotes a better or “less random” fill of the packed bed. The packing settles in a manner that orients more of the flat surfaces parallel to vapor and liquid traffic than perpendicular to flow. This orientation increases capacity while maintaining an effective surface area for vapor/liquid contact. Applications include uses in atmospheric and high-pressure distillation, demethanizers, deethanizers, acid gas removal, quench towers, and main fractionators. ASRP Packing is the mechanical equivalent of the Intalox Metal Tower Packing (IMTP®). The AMACS Saddle Ring Packing offers higher capacity and efficiency that the comparable size Pall Ring packing.
*IMTP® is the registered trademark of Koch-Glitsch LLC
The AMACS patented SuperBlend™ 2-Pac technology is the mixture of 2 different sizes of ASRP high performance packing that achieves the capacity (and pressure drop) of the larger packing, coupled with the efficiency of smaller packing. This improvement in performance is made possible because the smaller packing fills the interstitial voids between the larger packing to create a more effective surface area without the loss of capacity. SuperBlend 2-Pac Packing utilizes third generation packing to further increase column efficiency by 25% or column capacity by 15%. This technology was tested and verified by independent third-party research at SRP. Applications include absorption and stripping, fine chemical distillation, refinery fractionators, and retrofit opportunities.