AdBlue - Eliminating product quality risks with the Synthesis production

AdBlue produced with decomposition of solid urea in demineralised water by using small mixing units is a highly risky solution.

The production of AdBlue from 100 % solid technical urea is risky alternative to the recommended (by all truck manufacturers) synthesis production of AdBlue.

A decomposition plant does not require big investments (ca. 200,000 €) nor special authorisations since it only mixes and melts (by using recirculation pumps) urea in prills (grains) with demineralised water.

Urea is usually purchased in grains and in big bags (1000kg) from a plant of synthesis urea.

Therefore, the production requires (as shown by the diagram) other phases:

At the urea plant

1) Evaporation process
2) Prilling or granulating proces
3) Drumming process in big ba
4) Storage in a sheltered are
5) Transportation to the mixing plant

At the mixing plant

1) Big bag handling and storage
2) Decomposition

The only advantage of this kind of production is:

1) The production occurs near the place of consumption and therefore logistics is less burdensome.

However mixed urea production compared with synthesis production has the following disadvantages:

2) More likelihood of product being contaminated during the transportation, storage and handling phases
3) Small production capacity (usually 20 tons/8hr)
4) Product quality inconsistency: each lot is much different than the previous lot
5) Difficult compliance of product quality: when the parameters meet the standards, their values are very close to the limits of ISO 22241
6) Lack of homogeneity of product density due to improper mixing (anti-lumping must be added to the product in grains to avoid lumps; this addition remains in the mixture and can cause damages to the catalyser).

Recapitulating:

AdBlue produced by mixed urea is highly risky, AdBlue produced by hot melt urea (synthesis production) is safe and recommended by all truck manufacturers

Important instructions that should be considered in any case are set below:

1) Each lot of product must be checked to make sure that it is fully compliant with specifications
2) A detailed Analysis Certificate is issued for each lot and it should accompany every delivery. The certificate of conformity is not enough.
3) All the products are identified univocally by a lot number that allows complete traceability of the production chain and logistics in compliance with the specifications set by VDA and CEFIC.