Abstract: Various methods and systems are provided for authoring and presenting 3D presentations. Generally, an augmented or virtual reality device for each author, presenter and audience member includes 3D presentation software. During authoring mode, one or more authors can use 3D and/or 2D interfaces to generate a 3D presentation that choreographs behaviors of 3D assets into scenes and beats. During presentation mode, the 3D presentation is loaded in each user device, and 3D images of the 3D assets and corresponding asset behaviors are rendered among the user devices in a coordinated manner. As such, one or more presenters can navigate the scenes and beats of the 3D presentation to deliver the 3D presentation to one or more audience members wearing augmented reality headsets.

Abstract: A method of processing a cracked gas feedstream containing hydrogen and C.sub.1 to C.sub.6 and heavier hydrocarbons is described using a relatively low pressure as compared to conventional cryogenic separation processes. At pressures below 27 bars, the feedstream is dried and cooled in a series of steps to initially separate out essentially all of the C.sub.6 and heavier hydrocarbons forming a vapor stream containing the hydrogen, the C.sub.1 to C.sub.3 hydrocarbons and at least some of the C.sub.4 and C.sub.5 hydrocarbons. The C.sub.4 and C.sub.5 components act as an absorption liquid to lower the light ends partial pressure permitting the condensation of C.sub.2 and C.sub.3 components at higher temperature levels and permitting the operation at lower pressures. The vapor stream is then further cooled and separated in another series of steps and processed in a demethanizer column in a manner to provide a high pressure hydrogen and methane overhead product and a high recovery of C.sub.2 and C.sub.

Abstract: A low pressure cryogenic process is disclosed for recovering C.sub.2 and heavier hydrocarbons and particularly olefins from a refinery offgas containing hydrogen, methane, nitrogen oxide in addition to the C.sub.2 and heavier hydrocarbons. The conventional high pressures are eliminated and the temperatures are maintained higher than the temperature at which nitrated gums can form while still maintaining high olefin recovery. The feed is deethanized or depropanized to remove the C.sub.4 and heavier hydrocarbons at a temperature above the nitrated gum formation temperature. The overhead is then demethanized in a column using an enriching zone above the rectifying zone with a feed of C.sub.2 or heavier paraffins between these two zones.