Additional information about our unique direct contact biovertidryer biomass dryers:

Available in the following formats: the D-10, D-20 and D-30, all specifically designed to assist in the preparation of virtually any biomass for efficient combustion.

They all share a small foot print of 7 feet by 11 feet but vary in height

The common underlying proprietary principle of operation:

Simply stated, the biovertidryer is primarily a carefully engineered moisture removing vacuum system.

Air is drawn through the dryer and the biomass by an induced draft fan (or fans depending on the model)

A specially designed set of brush seals on each of the pass-through modules holds the biomass material being processed squarely in the ‘air’ stream for direct contact with the hot gas.

Moisture laden air is never reused.

The hot combustion exhaust gas instantly heats the moisture and the biomass at a rate established by the biovertidryer operator when he sets or adjusts the process controls.

The unique in-vacuum, controlled, direct contact design of Altentech’s biovertidryers reduces the amount of particulate emissions released into the atmosphere and effectively holds captive all of the gas and particulate until it is discharged from the fan.

Modular simplicity:

The biovertidryer has been specifically designed to minimize shipping and field assembly challenges

It has two basic modules that contain all other components. These modules are the:

Feeder assembly
Discharge assembly

Common components on all models – starting at the top and moving down:

Twin screw feeder and motor
Feeder chute c/w bindicator
Biomass mat feed control system
Upper shafts, sprockets and bearings
Timing gears and chain
Perforated flites, chains and flite brackets.
Catwalks and safety wire.
Ducts for first pass c/w thermocouple
Induced draft fan
Joint plates
Discharge conveyor
Main drive
Lower shafts, sprockets and bearings
Conveyor synchronization system
Flite cleaning brushes
Additional ducts

NOTE: Specially designed conveyer guides in each biovertidryer allows them to effectively remove moisture from biomass feedstock that shrinks during the drying process. (i.e.: peat moss or peat residue)

Heat source options:

All biovertidryer models can utilize waste heat / flue gases when available and of an appropriate minimum standard.

They can be matched and modulated with a high efficiency biomass burning cyclone furnace – effectively creating a virtually fossil fuel free system

Or, if a customer so desires, they could receive the necessary heat from less economical gas, oil, or propane fired burners

Efficient:

The biovertidryer has a 3:1 turndown ratio

Low power requirements:

On all models the main drive motor is located at the base and is only 0.5 hp. – as compared to rotary drum dryers which commonly require a main drive motor ranging from 25 hp. to 75 hp.

Each dryer comes equipped with predesigned fan or fans.

The D-10 has one 40 hp. fan - the D-20 has one 60 hp. fan - and the D-30 is equipped with two (2) fans; one 40 hp. and 60 hp.

Fans are governed by a variable speed drive that is controlled by a temperature sensor on the exhaust side of the dryer duct system.

Automation and Controls:

While customers can order their biovertidryer(s) without it, we recommend our Allen Bradley Controls package.

Two important benefits are:

First, it contains the operator interface touch screen so the operator can see the dryer running.

Second and most importantly: it serves as a watchdog for systems safety overrides. Any motor and /or data transmission device that faults the system is programmed to immediately signal an alarm notice to the operator.

At the top – The biomass feed system:

To ensure the proper consistent feed -rate of biomass product into the dryer the twin screw conveyor has been designed to and thus eliminate voids or over packing.

Because of the wide variety of possible installation demands each basic dryer does not come with a product delivery system. This allows each customer the flexibility of choosing the best means of moving their biomass to the feed shoot of the twin screw conveyers. (One common option would be a bucket elevator.)

In the middle – The biomass conveyers:

A timing mechanism holds the internal twin conveyors in sync and is monitored and checked continuously by an Allen Bradley PLC (Process Logic Controller).

This together with a set of duplicity detection switches performs as a mechanical safety supervisor system to assist the operator.

At the base - Drive motor and dried biomass discharge:

The main drive motor is located at the base of all biovertidryer models and is only 0.5 hp.

This is possible because the efficient design of the dryer utilizes the weight of the descending biomass mat.

More about the D-10:

The D-10 biovertidryer has a direct contact drying area of 64 feet square and 3 direct contact channels where heated combustion exhaust gases are drawn through and moisture is pulled out of the biomass being dried.

The D-10 is comprised of one feeder assembly module – and one discharge assembly

While more precise drying capacity can be determined by performing tests on the biomass feedstock you want to dry and the heat source option to be used, a D-10 biovertidryer will produce between 2 & 5 tons of dried product per hour. (In-lab testing can be performed at Altentech’s technical center*)

2 tons per hour is its approximate capacity when drying biomass from an 80% moisture content down to a 10% moisture content, while 5 tons per hour could be attained if the moisture was 45% and the output was set at 10%.

More about the D-20:

The D-20 biovertidryer has a direct contact drying area of 128 feet square and 5 direct contact channels where heated combustion exhaust gases are drawn through and moisture is pulled out of the biomass being dried.

The D-20 is comprised of one feeder assembly module – one discharge assembly module – and one ladder assembly module.

While more precise drying capacity can be determined by performing tests on the biomass feedstock you want to dry and the heat source option used, a D-20 biovertidryer will produce between 4 &10 tons of dried product per hour. (In-lab testing can be performed at Altentech’s technical center*)

4 tons per hour is its approximate capacity when drying biomass from an 80% moisture content down to a 10% moisture content, while 10 tons per hour could be attained if the moisture content was 45% and the output was set at 10%.

More about the D-30:

The D-30 biovertidryer has a direct contact drying area of 192 feet square and 8 direct contact channels where heated combustion exhaust gases are drawn through and moisture is pulled out of the biomass being dried.

The D-30 is comprised of one feeder assembly module – one discharge assembly module – and two ladder assembly modules.

While more precise drying capacity can be determined by performing tests on the biomass feedstock you want to dry and the heat source option used, a D-30 biovertidryer will produce between 6 &15 tons of dried product per hour. (In-lab testing can be performed at Altentech’s technical center*)

6 tons per hour is its approximate capacity when drying biomass from an 80% moisture content down to a 10% moisture content, while 15 tons per hour could be attained if the moisture content was 45% and the output was set at 10%.

*Altentech’s biomass feedstock testing protocol:

Sample of your biomass is sent to & tested in our laboratory dryer
The actual moisture content of the wet biomass is established over a 24 hours period
A drying curve is established
Altentech engineering / tech team can suggest / design wet biomass preparation stages
Available hot combustion exhaust gas quantity and quality is confirmed

Client selective options:

Bucket elevator - to bring the wet biomass from ground level up to the twin screw conveyor chute

Bag house - where needed for further improving exhaust gas discharge quality

Cyclone furnace package - can be used if appropriate waste combustion exhaust gas is not available or the client wishes to have a biomass drying system that is self-fueling and therefore virtually fossil fuel free

Allen Bradley Control package - This will be a standalone control system complete with operator interface remotely mounted to clients needs. There will also be an electrical panel with a variable speed motor control center.

Moisture measurement and production weighing system - integrated into and with the Allen Bradley Control package

Advanced engineering system - that will include the use of waste heat from the client and piped and cooled to a usable level. This will add additional fans and ductwork