Thermal Solids Processing

Bulk solids heat exchangers

Plate heating transfer technology has transitioned to the forefront of bulk-solids heating, cooling, and drying. It has found use in unlikely places such as polymers, chemicals, and even olive pits.

Plate heat exchangers offer indirect heat transfer because the two streams are separated. This means contamination between the stream being heated, cooled, or dried, and the effect of the heat transfer does not occur. Using bulk heat exchangers for heating or cooling material indirectly results in removing the risk of contamination and reducing the need for ventilation or dust collectors.

Heat exchanger industries

Bulk solids heat exchangers can be used in different multiple industrial sectors, such as the chemical industry for cooling fertilizers, the food industry for cooling sugar, coffee, and more. They can also be used in the metallurgical industry for cooling foundry sand, but also in the energy industry for heating vegetable seeds.

Bulk solids cooling

Bulk solid coolers are engineered to efficiently cool a variety of free-flowing bulk solids such as fertilizer, chemicals, plastics, dried biosolids, minerals, and many other types of granular, crystals and powders.

The basis of the bulk solids cooler technology is the gravity flow of product moving through a bank of heat exchanger plates cooled with water.

Bulk solids cooling generally occurs near the end of the processing sequence when powders or bulk solids must be cooled before storage or packaging to allow for safe handling and storage. Bulk solids cooling can be necessary if the production temperature is high, but the solids are processed downstream at a lower temperature.

The cooling process

The heart of the bulk solids cooler is the bank of exchanger plates. The product to be cooled moves slowly between the plates. Cooling water flows through the plates in counter flow and the product is cooled by conduction. Mass flow of the product is achieved using a discharge feeder mounted as an essential part of the exchanger below the plate bank.

Bulk solids drying

Drying solid materials is one of the most common and important in the chemical process industries since it is used in essentially every plant and facility that manufactures solid materials, in the form of powders and granules.

Drying is defined as the removal of water or other liquids from a solution, suspension by vaporizing it. It is a complicated process that involves both heat and mass transfer simultaneously, together with physicochemical transformations. Drying occurs as a result of the vaporization of liquid by supplying heat to wet granules, feedstock, filter cakes. and so on. Based on the mechanism of heat transfer that is employed, drying is categorized into direct, indirect, radiant, and dielectric or microwave drying.

Solid Drying Methods

Where fluid bed dryers are the most popular choice, they mainly handle solid feeds composed of discrete particles. There are other popular methods for drying solids materials, such as flash, tray, rotary tray, and then the fluid bed dryers.