Tank Coils

Tank coils, also called heating coils or cooling coils, are a type of heat exchange system used to heat or cool the contents of a tank.  They consist of a network of pipes or tubing that is installed inside the tank, and a heat transfer fluid (usually steam, hot water, or a chilled liquid) flows through these coils to transfer thermal energy to or from the substance inside the tank.

Tank coils have two main purposes

• Heating  -  In heating applications, steam or hot water is passed through the coils, and the heat from the fluid is transferred to the material stored in the tank.  This is commonly used in industrial processes where the contents of the tank need to be heated to a specific temperature. Examples include heating tanks used in food processing, chemical manufacturing, and oil refining.
• Cooling  -  In cooling applications, a chilled fluid is circulated through the coils, and heat is extracted from the substance in the tank, cooling it down. Cooling coils are often used in industries where temperature control is critical to maintaining the quality of the stored material.  For instance, cooling coils can be found in tanks used for storing beverages, pharmaceuticals, and certain chemicals.

The design and configuration of tank coils can vary based on factors such as the type of substance being stored, the required temperature change, the size of the tank, and the available heating or cooling resources.  Coils can be arranged in single or multiple loops, and the spacing between coils and the type of fluid used can impact the efficiency of the heat exchange process.

It's important to note that proper design and installation of tank coils are crucial to ensure effective heat transfer and to prevent issues such as uneven heating or cooling, corrosion of the coils, and contamination of the stored material.  Additionally, maintenance and cleaning of tank coils are important to prevent the buildup of deposits that can impede heat transfer efficiency.

Tank coils or heating coils are placed in tanks and are designed to transfer heat from steam vapor or condensate to the tank.  It is used when a LACT unit requires a certain temperature crude prior to shipment or in installations where heat loss will significantly viscosity of the tank fluid.  The photos below show a tank coil that is designed to be inserted into a 10,000 bbl tank.  This particular unit consists of heavy walled pipe welded to form a rudimentary coil.  It is also skid mounted so that it can be removed from service and replaced quickly.  

 

 

 

 

 

 

 

 

It is important to note for these applications when sizing this pipe to pay special attention to the corrosion both inside and outside the pipe.  A ruptured steam line discharging into an atmospheric tank will almost certainly damage the structure of the tank and could lead to catastrophic failure if the steam has no place to vent.