Selection of the correct dryer is a considerable investment and crucial for the process. Different variations in the dissimilar dryer are necessary to understand these variations. Other differences to take heat sources are steam tube drying versus direct heat drying. In this article, we will discuss the biomass dryer process.
Steam tube drying
There are rotating tubes in steam tube dryers with shell heat exchangers. The drum consists of a high-pressure chamber that disseminates steam into tubes running the length of the drum. The equipment necessary for thermal destruction is eliminated or reduced due to low-temperature processes.
The steam tube drier is extraordinarily effective and exhausts very little air, which considerably lowers stack loss. A steam tube dryer has a significantly smaller air pollution control system than a direct heat dryer since very little air is required to sweep off the water vapors.
The most user-friendly dryers are steam tube dryers. When the steam pressure is set, the appliance will use what is required to complete the task. Imagine having a technology that you can set and forget about. They are widely employed in the processing of high-moisture organic materials such as distiller's grain, gluten feed from the wet milling industry, oilseeds, and different types of sludges.
Direct heat drying
Hot gas is forced into a circular drum in a direct heat rotary drier. In low-temperature applications, its heat source may be as primary as a steam coil or it has a burner for greater temperatures. The burner could ignite into a chamber or the dryer drum (direct-fired means no combustion chamber).
Direct heat dryers often perform at their peak when the burner system can run with little to no extra air or with close stoichiometric gas-air ratios. As a result, the dryer can use less air to transfer heat energy.
The same end of the drum is fed with wet material (parallel flow) or the opposite end (counterflow), where it is scooped up and shrouded into the hot gas stream. The substance receives thermal energy from the hot gas, which heats the solids and water, ultimately causing the water to evaporate. Convection is the chief heat transmission mechanism.
A direct-fired unit will offer an effective drying solution by full utilization of all three heat transmission methods: radiation, convection, and conduction, assuming that the product is not damaged by the burner flame heat or the products of combustion. You might use a direct heat drier or a steam tube dryer to process heat-sensitive materials like biomass and organic goods.
Choosing a Steam Tube Dryer
For drying and processing inorganic and organic chemicals also other bulk solid commodities counting hemp, DDGs, wet corn, wood chips, soda ash, paper mill sludge, soy meal, and many more, we recommend using a steam tube drying system. Some advantages of this kind of dryer are the ones listed below.
Cost-effective
The heat source for steam tube dryers is steam. Because the dryer produces around 80% less exhaust gas than direct heat dryers, it is much less expensive and larger air pollution control equipment isn't needed.
Quality construction
An ASME vessel is a steam tube drier. As a result, it has more severe construction standards than conventional dryers.
Safe to operate
The atmosphere within the dryer is practically inert due to the high water-to-air ratio, considerably reducing the possibility of fire.
Final words
In this post, you will read about the drying process of wood pellets. However, a sawdust dryer is helpful for various waste materials like wood chips, wood shavings, bagasse, etc. If you want this type of process, you can reach Ecostan.