Controlled retting for consistent and high quality

With the current practice of dew-retting hemp stalks, the retting conditions are determined by the weather and the fungi in the soil. Dew retting is the process of separating fibers and wood in the hemp stalk for industrial uses with moisture and fungi on the farmland. This uncertainty makes it impossible to ensure a consistent quality of hemp fibers and hemp hurd. For consistent and high-quality hemp fibers and hurd, hemp needs to be retted in a controlled environment to break down the hemp stalk by decomposing the glue holding the stalk together.

Controlled retting: how does it work facilitates the controlled retting process in a box or container installation for retting and drying. This installation contains a heating element to control the temperature, a fan for the airflow, a humidifier, and a controlled inlet for the fungal culture. This allows our ABC software to tailor the environment within the installation to the needs of the fungi. This ensures the fungi will be evenly spread amongst the biomass.

This state is fostered by measuring and controlling the temperature, air humidity, and airflow. In five stages, this environment enables the fungi to consume the binding glue within the stalk. We are executing the retting regimen with the desired environmental conditions in an automatic fashion by means of the ABC software. In this way, we harbor the strengths of nature by using the principles of dew retting. While applying our knowledge and ABC software to create the best possible environment for evenly retting hemp stalks, resulting in consistent and high-quality hemp fiber and hemp hurd. At all times, our ABC software ensures the most efficient use of energy. 

Retting installation with boxes
Boxes are used for retting in order to achieve the most precise and best quality fiber- and hurd properties. The smaller volume of a box, up to 3.5m3 each, allows for the most uniform environment within this box.

Boxes retting and drying installation with airflow distribution

A. Heating of airflow
B. Fan
C. Nebulizing moisture
D. Absorption of fine water drips for humidifying air
E. Inlet for fungi and microbes
F. Distribution of air amongst the layers of boxes
G. Airflow per individual box layer
H. Outlet air with recirculation
I. Closed cell

Retting installation with containers
In a container, you are able to ret a larger volume of hemp stalks at the same time, up to 35m3. The environment is closed off with recirculating air most suited for retting. Creating a climate for evenly retting the hemp stalks and a consistent end result. 

Container retting and drying installation with airflow distribution

ABC: You instigate the retting process and check the progress using the ABC-software

A: Slightly heated outside air is circulated at the desired temperature
B: The ventilator blows in air at a preset airflow
C: A humidifier, filter and fungi inlet are situated in the vent
D: A sensor measures the incoming absolute humidity of the air
E: The air gets dispersed at the plenum at the bottom and rises equally through the biomass
F: Sensor measuring the absolute humidity of the recycled air
G: Air is circulated back to the ventilator

First, heat is added to the hemp stalks in order to raise the temperature of the product. Then moisture is added to be absorbed by the heated process air. In the second stage, this is continued. When the product is at the desired temperature and moisture content, the fungi are added. Stages three to five are used to harness this stage and let the fungi consume the glue holding the fibers and wood core together. Once the desired retting is accomplished, the process is terminated.

Drying after completion of retting
Once the retting process has been completed and terminated, the drying process will start within the same system. Heated airflow is blown through the warm product and dispersed out of the installation to drive off moisture. Once the hemp stalks in the facility have reached the desired moisture content, the drying process is stopped automatically by the ABC software, and the hemp stalk is ready for decortication. Read more on our website about our energy-efficient drying process.

Our knowledge
Over 45 years, we have perfected the art of controlling moisture content, airflow, and temperature within controlled environments. As applied to drying all kinds of agricultural products, our insights and solutions have been tested and innovated upon in many challenging environments. This knowledge lends itself to be applied to retting in a controlled environment, in which temperature, humidity, airflow, and input of fungi are measured and controlled.

This allows the cultivator to process the harvest with minimal loss of product, minimal use of energy, and maximum retention and consistency of quality. The ability to deliver fibers and woody core according to the demands of your buyers. Increasing the value of your harvest and providing consistent quality industrial hemp with minimal loss of income due to spoilage or unmet demands for hemp fiber and hurd quality. will also be attending the coming Cannadouro industrial hemp fair on 19 and 20 November in Porto. You can visit us there at stand 52.

For more information:
Tom Pankras 
+3168 333 2078
Hemp Drying 

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