Dewatering & Drying Systems

Dewatering & Drying Technologies are basically the mass transfer (removal) of water (or other liquid) from a solid, semi-solid or liquid. To design the proper dewatering or drying system the application parameters must be understood – primarily, what are the starting conditions and how dry is dry enough?

There are numerous technologies established for these types of applications, but the proper application of each technology is what must be understood. If the application is for the dewatering of municipal waste sludge to 10% moisture, the solution will likely look much different than if a powder must be dried to 0.02% moisture content.

In general, mechanical, and passive systems are used for dewatering and thermal/ microwave technologies are used for higher end drying applications.

Mechanical Dewatering

In general, mechanical dewatering systems are designed to remove the “free” external water from sludges, manure, biomass and other similar products by utilizing pressure or centrifugal forces. Common types of mechanical dewatering systems include;

Filter presses
Belt presses
Screw presses
Centrifuges
Drying beds
Screening
Sludge lagoons
Passive or low-pressure devices

Thermal Drying

To remove water that is absorbed into a material, general heat or energy needs to be imparted on the material to liberate the water from within. These types of thermal systems include;

Rotary dryers
Fluid beds dryers
Spray dryers
Thermal screw conveyors

These systems will typically require heating elements of some type and rely on convection, conduction and radiation of the heat (energy) from the outside inward. This type of heating vaporizes the external moisture and then slowly dries inward which usually creates higher external temperatures to achieve the internal moisture reductiosn needed to meet the requirements. Industrial Reps can work through these design options with our customers to establish the best solution for their projects.

Microwave Drying

Microwave drying systems are not as popular as the traditional thermal drying systems primarily because they have been viewed as requiring higher energy to operate but they do have a few significant advantages.
Microwaves are “Green” because they do not require heat from fossil fuels that emit CO2 and other greenhouses gases.
Microwaves penetrate deep into a product to excite water molecules and drive out internal moisture.
Do to the inherent volumetric heating, Microwaves dry more quickly
Microwaves heat more uniformly.
They are much easier to control and allow for more precise temperature and drying rate control.
They have an instantaneous on/ off capabilities

Dewatering & drying systems are used in many industries, including

Contact Industrial Reps

Regardless of the dewatering or drying system you require, Industrial Reps has experience with most all of the technologies available on the market today. Feel free to reach out to us to discuss your needs and how we may be able to help.