Chemicals & Materials

Reliable operation of an Olefin gas/liquid dehydrator requires careful attention to the integrity of the grid supporting the molecular sieve. Problems with retention of the sieve can stem from many points in the design, fabrication, and installation process for these assemblies. Two case studies...

Middle distillate hydrotreating is the most important refining process for the production of ultra-low-sulfur diesel, in which sulfur content is required to be less than 15 wppm. Hydrotreating is usually conducted in trickle bed hydrotreaters under steady-state operation with constant gas and...

Conventional ethylene technology uses three separate refrigeration compressor systems. Lummus has developed a patented mixed refrigeration system that provides the refrigeration needs from ambient to -140°C. Based on the inherent process flexibility with respect to feedstock variations, a...

There are several compressors within an ethylene plant, cracked gas and refrigeration compressors are the major ones. These compressors are high capital cost items. Performance and reliability of these units are especially important. The antisurge control system is designed to protect this asset. A...

Part A: The ethylene industry has been affected by the economic downturn. Plants have operated at low rates and have fed lighter feeds when possible. In this paper, the impacts of feed rates and types on process gas compressor operation and monitoring are discussed. Part B: Ethylene plant...

Advanced Process Control (APC) solutions are recognized as a process industry best practice and proven investment opportunity in many industries, including oil refining, petrochemicals, chemicals, plastics, polymers, air separation, pulp and paper, solids and drying, building products, life...

The standard way of testing a process causes the configuration and tuning of the PID control system for the process to be embedded in the model developed for the Model Predictive Controller (MPC). New technology has become available that can be used to interchange the independent variables with the...

This paper provides a brief global perspective to the GHG issue as it impacts the petrochemical industry and then focuses on the factors of developing carbon footprints for processes and products in the chemical industry. Using results from our recent studies we illustrate the complexities of...

The effective diffusivity of two fresh and two spent catalysts, previously deactivated for 18 months in a commercial unit, were determined. The effective diffusivities were measured using a shallow-bed reactor already developed for this purpose. Nitrogen, isopentane and isooctane effective...

Today's ethylene plants incorporate Turboexpander Systems in order to optimize cryogenic recovery and energy demand. The related residue gas molecular weight and flow rates depend directly upon the selected upstream feedstock gas composition, conversion, and feedrates. Various recent ethylene units...