The atmospheric crude unit is where everything starts in a refinery so it must operate reliably and efficiently for years at time. Choosing the correct operating parameters and matching column internals is imperative.

Whether you have a grass roots or revamp application, our experienced engineers can provide you with the best possible, most cost-effective, and robust solution to meet your most demanding requirements.

Crude atmospheric distillation process

The atmospheric crude distillation unit begins with desalting of the crude and then continues through significant heat exchange train and fired heater prior to entering the main atmospheric column. In some cases, a preflash column precedes the main column. The main column itself is designed with several sections with side product draws to produce the various product streams such as light ends, naphtha, kerosene, diesel, gas oil, and the bottoms reduced crude stream. Many of the side streams are stripped with steam to help maintain product specifications. The main atmospheric column is one of the most complex columns within the refinery.

Since all refinery products begin in the crude unit, reliability is of the upmost importance. The tower needs to run free of shutdowns and maintenance for periods of 4-6 years. The column must therefore be robust from a mechanical and operational standpoint while also being able to accommodate different feeds to the unit.

The main column is typically designed with high performance trays to allow for rate variations and resistance to fouling and corrosion over extended periods. Sulzer’s UFM Plus and UFM AF trays are often used to meet these needs.