CHEMICAL ENGINEERING

Chemical Engineering And My Subject Is Maintenance Strategy(Mechanical Engineering)

Chemical Engineering And My Subject Is Maintenance Strategy(Mechanical Engineering)

A- This patch chemical reactor can be considered as a plant unit for the following reasons:

1- It has a sub-function of the main process.

2- It is build up from several different equipments.

A Chemical reaction is a process that results in the conversion of chemical substances. The substance or substances initially involved in a chemical reaction are called reactants. These reactants are characterized by a chemical change and they yield one or more products. These products are generally different from the original reactants. Chemical reactions may be of different nature depending on the type of reactants, type of product desired, conditions and time of the reaction, for example, synthesis, decomposition, displacement, percipitation, isomerization, acid-base, redox or organic reactions.

Chemical reactors are vessels designed to contain chemical reactions. It is the site of conversion of raw materials into products and is also called the heart of a chemical process. The design of a chemical reactor where bulk drugs would be synthesized on a commercial scale would depend on multiple aspects of chemical engineering. Since it is a very vital step in the overall design of a process, designers ensure that the reaction proceeds with the highest efficiency towards the desired output, producing the highest yield of product in the most cost effective way.

This unit is critical for production because of the following: Production is affected when this unit fails. It can be source of cross contamination if it is not maintained well. It can cause hazard to plant safety and environment. A process in which all the reactants are added together at the beginning of the process and products removed at the termination of the reaction is called a batch process. In this process, all the reagents are added at the commencement and no addition or withdrawal is made while the reaction is progressing. Batch processes are suitable for small production and for processes where a range of different products or grades is to be produced in the same equipment for example, pigments, dye stuff and polymers. Continuous Process A process in which the reactants are fed to the reactor and the products or byproducts are withdrawn in between while the reaction is still progressing for example, Haber Process for the manufacture of Ammonia. Continuous production will normally give lower production costs as compared to batch production, but it faces the limitation of lacking the flexibility of batch production. Continuous reactors are usually preferred for large scale production. Semi Batch Process Process that do not fit in the definition of batch or a semibatch reactor is operated with both continuous and batch inputs and outputs and are often referred to as semi continuous or semi-batch. In such semi-batch reactors, some of the reactants may be added or some of the products withdrawn as the reaction proceeds. A semi-continuous process can also be one which is interrupted periodically for some specific ...