What does a reactor do in a refinery?

 Reactor Role in Refining.

A reactor is an essential piece of equipment used in the refining process in petroleum refineries. It is used to convert feedstocks into valuable products by inducing chemical reactions in a controlled environment. The reactor is responsible for carrying out the main conversion process, which involves breaking down larger hydrocarbons into smaller molecules or combining smaller molecules to create larger ones. In this article, we will explore the role of reactors in petroleum refining, their types, and the different types of reactions they are used for.

Role of Reactors in Petroleum Refining

Petroleum refining is a complex process that involves transforming crude oil into a wide variety of products, including gasoline, diesel, jet fuel, lubricating oils, and other valuable chemicals. Crude oil is a mixture of different hydrocarbons, which are separated into different fractions through distillation. However, the crude oil fractions are not yet suitable for use as fuel or chemicals because they contain impurities and have undesirable properties, such as high sulfur content.

To make these fractions usable, they are subjected to further processing using various refining techniques, including cracking, reforming, hydroprocessing, and others. These refining techniques rely on catalysts, pressure, heat, and other factors to induce chemical reactions that transform the crude oil fractions into desirable products. Reactors are a key component of these refining techniques, providing the necessary environment for the chemical reactions to take place.

Types of Reactors

There are many types of reactors used in petroleum refining, and each has its own specific application. The most common types of reactors used in petroleum refining are:

1. Fixed Bed Reactors: Fixed bed reactors consist of a cylindrical vessel filled with a solid catalyst. The feedstock is pumped through the reactor, and the chemical reactions take place on the surface of the catalyst. The catalyst is usually porous, allowing for high surface area and contact with the feedstock. Fixed bed reactors are commonly used in catalytic cracking, hydrocracking, and other catalytic processes.

2. Fluidized Bed Reactors: Fluidized bed reactors are similar to fixed bed reactors, but the catalyst is fluidized by a high-velocity stream of gas or liquid. The fluidized catalyst creates a homogeneous environment, allowing for efficient contact with the feedstock. Fluidized bed reactors are commonly used in catalytic cracking, catalytic reforming, and other catalytic processes.

3. Stirred Tank Reactors: Stirred tank reactors consist of a cylindrical vessel with an impeller that agitates the feedstock and catalyst. The agitated mixture creates a homogeneous environment, allowing for efficient contact between the catalyst and feedstock. Stirred tank reactors are commonly used in hydroprocessing, such as hydrocracking and hydrotreating.

4. Tubular Reactors: Tubular reactors consist of a long, narrow tube through which the feedstock and catalyst flow. The tube may be heated or cooled to control the temperature of the reaction. Tubular reactors are commonly used in catalytic reforming, and other catalytic processes.

Types of Reactions in Refining

Reactions that take place in reactors during petroleum refining are categorized into two types: thermal and catalytic reactions. Thermal reactions are non-catalytic reactions that occur at high temperatures and pressures, while catalytic reactions take place in the presence of a catalyst.

1. Thermal Reactions: Thermal reactions are used to convert feedstocks into lower boiling point products. They involve breaking the larger hydrocarbon molecules into smaller ones through the application of high temperatures and pressures. The most common thermal reactions used in refining are thermal cracking, visbreaking, and coking.

2. Catalytic Reactions: Catalytic reactions are used to produce high-quality products with desirable properties. They occur in the presence of a catalyst, which provides a lower activation energy and speeds up the reaction. The most common