Process Selection DescriptionAll processes are subject to disturbances that tend to change operating conditions, composition and physical properties of the stream. In order to minimize the ill effects that could result from such disturbance, chemical plants are implemented with substantial amounts of instrument and automatics control equipment. In critical cases and in especially large plants, moreover, the instrumentation is computer monitored for convenience, safety and optimization.Process synthesis is an important thing on chemical plant design. For this process, our production is 10000 . For this production, butadiene is the major product while hydrogen. For our reactant, we are using ethanol and water. Production of 1-3 butadiene has been carried out in one-step process. At feed (stream 1), 95% of ethanol and 5% of water to the stream 1. This is because of this process followed Ivan Ostromislensky process by using 95% of ethanol and 5% of water to the stream. Production was assumed to operate 24 hours per day for 350 days/ year. Based on our PFD, the main equipment are operated and explained below.

Section 00 : Dehydrogenator Reactor and Vaporizer

For Stream 1, Ethanol and water are entered to the stream and was fed to the vaporizer. This process followed Ivan Ostromislensky process, so the percent by mass of ethanol is 95% while water is 5% in the liquid phase. Then, the ethanol and water are vaporized into the gas phase so that the reaction to become acetaldehyde can occur. The reaction takes place at 25oC ( Room Temperature) and increased in 100 oC in stream in order to produce ethanol in the gas phase. The liquid stream is then sent to a heat exchanger (E-101) where it is heated and partially vaporized Reaction inside the vaporizer :

A significant amount of hydrogen is produced in the first reaction, which must be removed from the product stream before it enters the second reactor.While in the reactor, the outputs from vaporizer are fed to the reactor. Production of acetaldehyde and hydrogen will produce in the dehydrogenator reactor from ethanol and water in the gas phase. The reaction occurs in high temperature to produce acetaldehyde. A significant amount of hydrogen is produced in the first reaction, which must be removed from the product stream before it enters the second reactor.

The reactor inside the conversion reactor is :

Section 01: Conversion Reactor and Cooler

Butadiene production is produced by oxidized of the acetaldehyde from ethanol. The operating temperature from 400oC-450oC , which reacts with additional ethanol over a tantalum-promoted porous silica catalyst at 325350 C to yield butadiene (Kirshenbaum, 1978). These processes are widely used in Russia, China, India and United States (Bloesch, 2013) . The conversion on the reactor is 80% to produce butadiene.

The product of the conversion reactor then will be cooled down to produce the butadiene in liquid phase. So that the product and other side product can separate, So that the product can increase the purity of the product.

Section 02 : Distillation Column 1 and Distillation Column 2

In this section, the product of the cooler will purify in the distillation column so that the product will get the better composition. So, for this process, the 2 distillation column was installed. Also, the product and byproduct can separate by having a different votalities and boiling point.

First Distillation ColumnFor the first distillation column, the ethanol and water are separated from acetaldehyde and butadiene. So the operating temperature should be less than 75oC and more than 22oC.Butadiene(-4oC) and acetaldehyde(22oC) will produce gas phase because of the operating temperature is below than both of the boiling point. So that the product will become effluent. While ethanol and water will become raffinate and entered stream 11.

Second Distillation ColumnFor the second distillation column, the acetaldehyde and butadiene will entered stream 10. The operating temperature should be less than 22oC and more than -4oC. So, Butadiene will vaporize and become a gas phase(effluent) while acetaldehyde will condense to become liquid phase(raffinate). So pure butadiene will produce in the stream 12 and the high purity will be achieved.