A dynamic simulation of a styrene production process

Dynamic simulation plays a crucial role in process engineering, especially in designing control systems. As the interest in dynamic simulation for effective control and operation rises, the goal of the paper is to study and improve the dynamic performance of a styrene production process using simulation software to tackle various process design problems. The simulation process is carried out in four stages. In the first stage, flowsheet topology and process parameters are selected to meet the requirement of the main product. Control systems are designed for each piece of equipment in the process in the second stage. Both of the stages mentioned earlier are conducted in a steady-state environment. After finishing the second stage, steady-state simulation is complete. The third stage involves tuning control parameters of control loops in a dynamic environment. In the final stage, the performance of the system is tested by introducing disturbances in the form of pulse inputs. The results of the dynamic simulation illustrate that the control system is significantly influenced by the ethylbenzene feed flowrate disturbance. The production rate is heavily affected by the disturbance, while the production quality is assured. The average settling time of the process is 270 minutes.

A Condensed Excited (Rydberg) Matter: Perspective and Applications

A condensed excited matter called Rydberg Matter (RM) have been studied experimentally for 30 years, but have not sparked widespread attention yet, unlike ordinary Rydberg atoms. RM formed by clusters of Rydberg atoms at a solid surface have a longer lifetime compared to Rydberg atoms, and is liquid-like. This review describes how the RM state is generated, and its potential applications. These include using RM for research into catalysis, space phenomena and sensor applications, or for producing environmentally friendly energy. A background on RM is presented, with its structure and special properties, and the working principle of RM generation. The experimental set-ups, materials, and detectors used are discussed, together with methods to improve the amount of RM produced. The materials used for the catalysts are of special interest, as this should have a large influence on the energy of the RM, and therefore also on the applications. Currently most of the catalysts used are potassium doped iron oxide designed for styrene production, which should give the possibility of improvements. And as there is little knowledge on the exact mechanisms for RM formation, suggestions are given as to where research should start.

Liquid phase dehydration of methyl phenylcarbinol to styrene

The industrial styrene production by the method of vapor-phase methylphenylcarbinol (MPhC) dehydration was introduced for the first time in our country within the joint propylene oxide and styrene production consisting OAO «Nizhnekamskneftekhim» facility. This process makes it economically feasible to obtain a combined product – propylene oxide and styrene. However, continuous process exploitation at the OAO «Nizhnekamskneftekhim» facility allowed revealing a number of significant faults caused by economic and environmental factors toughening. First of all it is high energy consumption due to high process temperature and high water steam consumption for steam dilution, which affects the increase in the cost of production. In almost all technological scheme areas of this production, high boiling by-products, so-called high boiling components, are formed. One of these problem solution versions is the transfer of production to a new technology of styrene production by MPhC dehydration, which is carried out in the liquid phase at lower temperatures (up to 190 °C) using new homogeneous highly selective catalysts that exclude the by-products formation, including high-boiling components. The principal advantage of this technology is to reduce the cost of marketable styrene by reducing energy costs (heat, recycled water, water vapor, fuel gas, electricity), reducing the metal consumption of the technological scheme and increasing styrene production by reducing the amount of waste. The comparative tests results with three samples of homogeneous catalysts activity in the MPhC dehydration into styrene process are presented in the work. The tests were carried out under conditions of periodically and continuously operating laboratory installations made of glass, equipped with dosing, condensation, separation and collection systems for reaction products. Quantitative composition of reaction products is identified by chromatography methods. As a result of the conducted tests, in the presence of the used catalysts, the process control modes were selected, and the installations efficiency was checked.