Isvag processes residual waste in a sustainable and ecological manner and meets the strictest Flemish standards and European guidelines regarding emissions.

Isvag processes the residual waste from 1 000 000 inhabitants from the Antwerp region.

A number of strict Flemish and European standards apply to waste processing installations such as Isvag. Isvag therefore has a high-quality flue gas treatment plant. During the purification process, products such as slaked lime, sodium hydroxide and urea are used to eliminate certain harmful substances in the flue gases. The timely delivery of these products is crucial for the continuous operation of the treatment plant.

The contract has therefore been subdivided into the following lots:

- Lot 1 'slaked lime Ca (oH) 2',

- Lot 2 'Sodium hydroxide 30%',

- Lot 3 'urea 45% ,.

The slaked lime is used for making lime milk. This product is sprayed over the flue gasses in the half-wet wash using an atomizer.

The estimated annual quantity of slaked lime that ISVAG purchases comes to 1 100 tonnes.

The product specifications for slaked lime Ca (OH) 2 - bulk are:

- Ca (OH) 2 total 92.5% (*),

- free water 0.84% (*),

- CO2 2.72% (*),

- MgO 0.40% (*),

SiO2 0.30% (*),

- solubility index 50 s (*),

- Screening throughput 200 μm 99.4% (*),

- sieve drop through 90 μm 95.1% (*),

- density tamped 0.86 g / mL (*),

- bulk density 0.52 g / mL (*).

(*) Guide values.

ISVAG always orders a full load, around 25 tonnes. The goods must be delivered on Isvag, after calling by e-mail and within the maximum period of 2 working days, unless otherwise specified. After each call, an order confirmation must be sent by the supplier confirming the delivery date.

The chemicals must be discharged according to strict discharge procedures, see chapter technical provisions.

The sodium hydroxide is added to the process water from 1 of the 3 baths of the wet wash in which the flue gases are washed.

The estimated amount of sodium hydroxide that ISVAG purchases is 510 tonnes per year.

The product specifications for Sodium hydroxide 29% (NaOH) - bulk are:

- concentration 30 ± 1% (w / w),

- chloride max. 100 ppm (*),

- sulphate max. 100 ppm (*),

- carbonate max. 1000 ppm (*),

- iron max. 5 ppm (*),

- mercury max. 0.1 ppm (*).

(*) Guide values

ISVAG always orders a full load, around 28 tonnes. The goods must be delivered on ISVAG, after calling by e-mail and within the maximum period of 3 working days, unless otherwise specified. After each call, an order confirmation must be sent by the supplier confirming the delivery date.

The chemicals must be discharged according to strict unloading procedures, see chapter Technical provisions of the specifications.

The urea is injected into the flue gases. Because of the catalyst's action, the NOx reacts with ammonia gas, leaving only harmless gases and water.

The estimated amount of urea that ISVAG purchases is 550 tonnes per year.

The specifications for Urea 45% without additive (*) are:

- 45 ± 1% concentration (w / w),

- total nitrogen ≥ 20.5% (w / w),

- biuret ≤ 0.5% (w / w),

- ammonia ≤ 0.2% (w / w),

- undissolved particles ≤ 10 mg / kg,

- formaldehyde ≤ 10 mg / kg,

- pH (10% urea solution) ≤ 10,

- water (**) Rest up to 100%.

(*) The application requires no additive (against the formation of limestone).

(**) The water used to prepare the 45% solution must be demineralised.

ISVAG always orders a full load, around 28 tonnes. The goods must be delivered on ISVAG, after calling by e-mail and within the maximum period of 3 working days, unless otherwise specified. After each call, an order confirmation must be sent by the supplier confirming the delivery date.

The chemicals must be discharged according to strict unloading procedures, see chapter technical provisions of the specifications.