Chemical Process Engineering & Simulation

Crystallizer Design Considerations: Figure 1. Forced circulation evaporative crystallizer. The function of a crystallizer is to produce crystals of a given size specification from a feed are a specific rate. A suitable and adequate supersaturation is created by cooling the feed or by partial evaporation of the solvent. The second method is more common in industrial practice. It has been mentioned before that a narrow particle size distribution of the product is desired to maintain a good product quality. Besides the correct supersaturation and environment (i.e. agitation, pumping rate etc.), techniques like redissolution or classified product removal are helpful to achieve a better product quality. Bath crystallizers require seeding (i.e. addition of fine crystals that act as nuclei). Secondly, nucleation occurs continuously in a continuous crystallizer and seeding is not generally necessary.  The more important parameters and quantities involved in the design of a c...

Aspen Plus Fluidized Bed Reactor Simulation: Fluidized Bed Reactor (FBR) The fluidized bed reactor is a reactor in which the fluid from the bottom of the reactor keeps the solid catalysts suspended inside the reactor. This reactor has an advantage over traditional packed bed reactor because it has a better heat and mass transfer. In industry, the fluidized bed reactor is most prominently used to produce products which cannot be efficiently manufactured using more commonly using more commonly used reactors (Towler, 2012). A fluidized bed reactor is used to produce a variety of products. In the fuel industry, a fluidized bed reactor is used to produce gasoline, propane, butane, and propylene (Washington University, 2016). While these are some of the common uses of fluidized bed reactor, good mixing, and energy efficient nature of the reactor allows a fluidized bed to be used in producing a less conventional fluidized bed reactor product such as photovoltaic cells. REC Sili...

Introduction:   Process simulation is extremely beneficial to engineers, allowing them to further understand processes, identify process advantages and limitations, and provide quantitative process outputs and properties. Modeling reactors and their corresponding reactions is difficult by nature but can be rewarding if done correctly. This page provides essential information on the topic of reactor simulation using the computer program Aspen HYSYS.   Aspen HYSYS Reactor Simulation Basics: The HYSYS program allows the user to define reactions primarily based on desired model outputs and available information. After defining process components, the user can choose a reaction type as listed in the HYSYS reaction section below. HYSYS includes a number of different reactor models for the various reaction types, desired outputs, and specification limitations as well as standard PFR and CSTR models as described in the HYSYS reactors section below.  Unlike other simu...

Advantages of Process Intensification: Although [1] named the reduction of the cost of a production system as the primary incentive for process intensification (PI) there are other advantages. They are: Improved quality More efficient use of raw material Reduced energy consumption Improved product quality Greater reliability Reduced waste Easier scale-up Distributed plant These advantages will now be discussed separately. Improved Safety: Significantly smaller plants have smaller contained volumes. If all other risks remain equal, a reduced plant inventory must increase the safety of a plant. The major safety, health and environment related incidents such as Flixborough, Bhopal and Seveso all occurred when a large volume of material escaped. It has been mentioned in [6] that “What is not there cannot leak, explode or otherwise endanger life or the environment”. It is possible that the contained energy of smaller plants will be small enough that an explosi...