Supply of fresh powdered activated carbon 2022 — 2024

Delivery of fresh powdered activated carbon for wastewater treatment (640 t) for 2 years (approx. 320 t per year). The call is made in partial quantities. The delivery must take place in the silo vehicle.

1st stage participation competition:

In stage 1, the participation competition is checked with all of the following documents. Prerequisites for participation in the competition must be demonstrated:

- Proof of the explosion protection key figures of powdered activated carbon:

Minimum ignition energy greater than 100 joules determined with the 20 liter ball

Dust explosion class 1

glow temperature greater than 400°C

Ignition temperature greater than 290°C

Specific electrical leakage resistance of less than 10³ Ohm m

confirmation that the powdered activated carbon offered has a burning number of 1 or

2.

- Proof/report on the suitability of powdered activated carbon for DOC or SAK254nm reduction and trace material removal (carbamazepine and diclofenac) in municipal wastewater

- Confirmation of the ability to supply 640 tons of fresh powdered activated carbon from December 2022 up to and including December 2024.

Arrival in the silo vehicle. Release in partial quantities.

2nd stage participation competition:

Participants are requested to submit an offer. At the submission date, the price must be communicated and a sample (at least 10 liters) of the powdered activated carbon offered must be submitted.

3rd stage investigation of the test coals offered

On behalf of the ZVK Steinhäule, these samples are examined by an independent institute with the wastewater of the ZVK Steinhäule with regard to DOC changes and the reduction of trace substances.

4th level rating:

The contract is awarded to the most economically advantageous offer. The criteria for this are the price and the DOC withdrawal rate of the powdered activated carbon used. The criteria are the price in euros/kg of powdered activated carbon divided by the percentage reduction in the DOC value. The percentage reduction in the DOC value and SAK254 nm value (as a control measurement) is determined by means of 3 stirring experiments at a concentration of 10, 20 and 40 mg of powdered activated carbon per liter of wastewater from the Steinhäule sewage treatment plant. The percentage withdrawal rate of carbamazepine and diclofenac must be greater than 70% with a 10 mg powder activated carbon dosage per liter of wastewater from the Steinhäule sewage treatment plant.