Indirect Cooling and Heating for Granular and Powdered Solids

The ZZ Thermal Bulk Solids Heat Exchanger is designed for the efficient and controlled cooling or heating of granular, powdered and

 other free-flowing bulk solids.

Based on laser-welded Pillow Plate technology, the heat exchanger uses a moving-bed process in which the solid material flows 

gradually through the equipment while exchanging heat indirectly with a heating or cooling medium.

Compared with conventional fluidized-bed systems, the indirect moving-bed design eliminates the need for fluidizing air, reduces 

dust generation and product degradation, and provides precise temperature control with low energy consumption.

The modular design also allows the heat transfer area and capacity to be adapted to different process requirements.

How Does It Work?

The bulk solid enters the heat exchanger from the top and flows downward by gravity through a controlled moving bed.

Inside the equipment, the material comes into indirect contact with the heat transfer surfaces formed by laser-welded Pillow Plate 

panels. A heating or cooling medium flows inside the Pillow Plates, transferring heat through the stainless steel surfaces without

 direct contact with the product.

The controlled movement of the solid material provides a stable residence time and uniform heat transfer throughout the process.

No fluidizing air is required.

This makes the system particularly suitable for dusty, temperature-sensitive or contamination-sensitive bulk solids.

Key Advantages

Indirect Heat Transfer

The product is heated or cooled indirectly through the Pillow Plate surfaces. There is no direct contact between the product and the 

heating or cooling medium.

Controlled Product Flow

The moving-bed design allows the bulk material to flow gradually through the equipment, providing controlled residence time and

 stable thermal treatment.

Uniform Temperature Control

The large and continuous heat transfer surface provides efficient and consistent heat transfer, helping achieve a uniform product

 temperature.

Low Dust Generation

Unlike fluidized-bed systems, the process does not require high-velocity air to fluidize the product. This significantly reduces dust

 entrainment and the associated air-handling requirements.

Reduced Product Degradation

The gentle movement of the material minimizes mechanical agitation, vibration and excessive particle movement, helping reduce

 product breakage and degradation.

High Energy Efficiency

Because heat is transferred directly through the metal heat transfer surfaces, the system avoids the energy consumption associated

 with large volumes of process air and air-handling equipment.

Modular Design

Pillow Plate modules can be configured and expanded according to required capacity, heat transfer area and process conditions.

Easy Cleaning and Maintenance

The all-welded Pillow Plate construction eliminates gaskets and adhesives on the heat transfer surfaces and provides a robust 

solution for demanding industrial environments.

Typical Applications

ZZ Thermal Bulk Solids Heat Exchangers can be used for indirect cooling or heating in a wide range of industries, including:

﹡Fertilizer production

﹡Mineral processing

﹡Salt processing

﹡Sugar processing

﹡Starch and food ingredients

﹡Chemical powders and granules

﹡Metallurgical materials

﹡Industrial minerals

﹡Other free-flowing bulk solids

Typical applications include:

Bulk Solid Cooling

Cooling hot granular or powdered products before storage, packaging or further processing.

Bulk Solid Heating

Controlled heating of solid materials to achieve the required process temperature.

Product Temperature Conditioning

Bringing bulk solids to a specified temperature while maintaining product quality and minimizing contamination.

Typical Materials

The system can be adapted for different types of granular and powdered materials, including:

﹡Granules

﹡Crystals

﹡Powders

﹡Pellets

﹡Prills

﹡Salt

﹡Fertilizer

﹡Sugar

﹡Starch

﹡Minerals

﹡Chemical solids

The actual design depends on material properties such as particle size, bulk density, flowability, moisture content, inlet temperature 

and required outlet temperature.

Why Pillow Plate Technology?

The heart of the system is the laser-welded Pillow Plate heat transfer panel.

Two metal sheets are welded together according to a defined welding pattern and then hydraulically formed to create internal flow

 channels.

This construction provides a large heat transfer surface in a compact configuration while maintaining a robust, fully welded structure.

For bulk solid applications, Pillow Plate technology offers several important advantages:

﹡Large effective heat transfer area

﹡Fully welded construction

﹡No gaskets or adhesives

﹡Flexible flow-channel design

﹡Low pressure drop on the heat transfer medium side

﹡Good resistance to fouling and clogging

﹡Modular construction

﹡Suitable for demanding industrial applications

Different materials, plate thicknesses, channel configurations and heat transfer media can be selected according to the process 

conditions.

Customized for Your Process

Bulk solids have significantly different flow, thermal and mechanical characteristics. Therefore, the heat exchanger should be designed

 according to the actual product and process conditions.

ZZ Thermal can develop a customized solution based on:

﹡Product type

﹡Particle size and distribution

﹡Bulk density

﹡Product flow rate

﹡Inlet and outlet temperature

﹡Required heating or cooling duty

﹡Heat transfer medium

﹡Allowable pressure drop

﹡Residence time

﹡Material of construction

﹡Available installation space

The equipment can also be integrated with temperature control, heat transfer fluid circulation and automatic process control systems.

Talk to Our Engineers

If you are looking for an efficient alternative to air-based or fluidized-bed cooling and heating systems, our engineers can evaluate 

your bulk solid application and develop a suitable Pillow Plate heat exchanger solution.

Send us your product and process data to discuss the required heat transfer area, capacity and equipment configuration.