Incincerator Bottom Ash (IBA)


Incinerator Bottom Ash (IBA) has been used in The Netherlands already since 1981 as a certified product as an unbound material in groundwork and civic engineering projects to replace sand and gravel; for instance as embankment material in sound walls or roads, or for the redesign of former landfill sites (tips).

The use of Incinerator Bottom Ash (IBA) fits nicely in a circular economy. In The Netherlands, there is an annual need for 120 to 140 million tons of building materials, which are for the main part imported from abroad. By using Incinerator Bottom Ash (IBA), a saving is achieved on the use of primary raw materials, which prevents our living environment from being further negatively affected.

Green Deal

Responsible use of unbound Incinerator Bottom Ash (IBA) has been possible since 1981 provided the protective measures in the field of IBC (isolation, control and monitoring) have been implemented carefully. Of course, further improvement of the quality is preferred. This is why the Dutch government closed the Green Deal ‘Verduurzaming Nuttige Toepassing AEC bodemas’ with the waste-to-energy plants (WTEP) in 2012.

The objective was that as of 2017 half of all bottom ashes produced on an annual basis would be processed or reprocesses. As of 2020, this must be 100%. This can be achieved in the following two manners:
  1. in unbound uses that requires the bottom ash to be rinsed intensively, the main disadvantage of which is that the production of contaminated water and sludge fraction. The latter must be disposed of in a landfill.
  2. in bound uses whereby contamination is enclosed to avoid leaching. The WTEP granulate can be used in in concrete products and solid foundations.
At this stage, Rock Solid has opted for the second approach.

WTEP granulate

WTEP granulate is the result of additional treatment of Incinerator Bottom Ash (IBA). Is can be used for bound uses such as the following:

Due to our high-quality manner of reprocessing, we guarantee that our certified WTEP granulate is suitable for these uses.

Contact us

(Cold) immobilisation


Immobilisation is a known and approved technology that uses mineral binding agents (cement or cement substitutes), possibly augmented with additives, to create useful uses from rest streams. The cement itself provides cohesion and will enclose any contaminations in a sustainable manner. 

More about (Cold) immobilisation