FAQ EloDry®

Data and dimensions

What is the standard water evaporation capacity for the different dryer sizes?

EloDry® NT08: 220 kg H2O/hvapor
EloDry® NT32: 440 kg H2O/hvapor
EloDry® NT24: 660 kg H2O/hvapor
EloDry® NT32: 880 kg H2O/hvapor
EloDry® NT40: 1,100 kg H2O/hvapor

What is the minimum required DS content of sludge input?

20 %, remixing of dry sludge for DS < 20 %

What is the range of DS content in the dried sludge, which can be achieved?

> 85 %
EloDry® is a belt dryer to fully dry sludge to > 85 %, which is constantly measured.

How much electricity is required per t H2O/hvapor?

Max. 50 kWh

What is the specific heat requirement per t H2O/hvapor?

From approx. 750 up to approx. 850 kWh

What kind of equipment is used for the distribution of the sludge on the belt?

1.) distribution screw or
2.) extruding system

Optional:

- Crusher
- Remixing of dried sludge

What is the typical running time of the dryer?

24/7
Max.: 8,200 h/a

What is the footprint for the dryer?

EloDry® NT08: 4.4 x 3.0 x 2.8 m
EloDry® NT16: 7.1 x 3.0 x 2.8 m
EloDry® NT24: 9.7 x 3.0 x 2.8 m
EloDry® NT32: 12.4 x 3.0 x 2.8 m
EloDry® NT40: 15.0 x 3.0 x 2.8 m

Which materials are used for Frame, cover, and heat exchangers?

Stainless steel, AISI 304

Which materials are used for Belts?

Polyester with woven bronze wires

How is the process control managed?

The process control is managed by a PLC with a touch screen as an HMI. Data from/to customer’s SCADA system will be provided via Industrial Ethernet and data blocks.

Maintenance

What is the daily time required for maintenance?

The dryer is running fully automatically. The required time for maintenance is limited to plausibility checks of measured values on the HMI resp. on the SCADA system and visual checks of the drying plant.

Further time will be necessary for the analytical works, mainly for determination of the DS-concentration of the sludge. According to our experiences approx. 1 h/d for all of these works is sufficient.

Are there any special maintenance access provisions?

The dryer should be placed on strip foundations (approx. 800 mm height) because the discharge screw conveyor and the pipes for water have to be placed underneath.

There should be approx. 1.5 m space for maintenance on both sides of the dryer.

Is there any manual maintenance required, and how often?

Three times a year there will be a “small” manual cleaning of the dryer, approx. ½ day.
Once a year, there will be a “big” cleaning with inspection, approx. three days.

Depending on the sludge and distribution system, dust filters have to be changed regularly.

What is the lifetime of the belts?

The individual lifetime and can vary between two and ten years.

Operation

How is the DS content of the dried sludge controlled and adjusted?

1.) Temperature measurements inside the dryer

2.) DS-measurement at the exit of the dryer

How do you prevent odor emissions?

The EloDry® dryer operates in a slight vacuum, so no odor is emitted into the environment.

Which exhaust air cleaning devices are required?

The requirements for waste air cleaning are depending on the quality of the incoming sludge. For fresh, well-digested sludge an acid scrubber will usually be sufficient (depending on regional legislation).

What is the expected amount of waste air to be treated?

The minimum amount of exhaust air is 5.000 m³/h for each dryer and increases with the throughput and size of the dryer. Optionally part of the waste air is recirculated after cooling to reduce waste air stream.

What is the expected average quantity and quality of the produced wastewater?

The quantity will usually be in the range between 80 and 500 L/h with increased concentrations of Ammonia. The COD and BOD5-concentrations are negligible.

Can this wastewater be drained back into the feed of the WWTP?

Yes.

Is there a risk of corrosion in the pipes and heat exchangers due to condensation in the waste air?

No. Due to the choice of the material of the dryer and peripheral equipment, no corrosion has to be expected.

Safety

Which measures have to be provided for explosion protection?

The EloDry® dryer is Ex-zone free.

Which are the standard safety devices of the EloDry® dryer?

Constant automatic monitoring of the formation of smoke, dust, and temperature.
The EloDry® dryer is equipped with a sprinkler system in case of smoke detection.