100% recycling of used tar asphalt

Thermal cleaning process results in clean sand, gravel and filler

In the Rotterdam port area - Vondelingenplaat - a new thermal cleaning plant is currently being constructed. In this plant, old asphalt containing tar, mainly from roads in the Netherlands and surrounding countries, is completely converted into primary raw materials, electricity and heat. The way this is done is unique in the world.

The turbine building of the thermal cleaning plant in Rotterdam consists of two volumes; a high-rise building and a low-rise building. The low building will soon house the control room with computers that will control the cleaning process and the turbine. Seven transformers will also be set up here. In the high building, a steam turbine and a large generator will be installed.

Thermal cleaning

Recycling the asphalt is done in a rotating drum oven at a temperature of about 1,000°C. Due to this high temperature, all harmful substances present in the asphalt are completely burned. This thermal cleaning process results in clean sand, gravel and filler, ready for reuse. The energy from the hot gases is recovered in the form of steam and converted into electricity via a steam turbine. Thanks to this innovative approach, some 210,000 megawatt hours of electricity are generated per year. With this amount, about 50,000 households can be powered.

Phase 2 is in full swing.

Cooperation between principals and contractors

Middelwater Construction operates in the low-rise and high-rise sections. The low-rise section consists of transformer rooms, a control room and office facilities. The high-rise section consists of the turbine room. The turbine requires a heavy, concrete foundation, which was realized by GMB Haven & Industrie; the shell is composed of a steel structure, clad with sandwich panels and masonry. "It feels good to take on the execution as a construction team," says John van Rees, project manager of Middelwateringbouw. "This is a very complex project in which the very latest techniques are used. For the construction part, we are working together with our client GMB Haven & Industrie. It is characteristic of this project that clients and contractors join forces to come up with the best solutions."

Cramped construction site

In addition to the innovative challenges, Mediumwater Construction is dealing with the more regular challenges. For example, the turbine building is being realized on a tight construction site, where it is not the only one operating. Middelwateringbouw is realizing one building section, while the entire "plant" consists of several building sections with different contractors. Cranes, trucks and no fewer than 150 skilled workers move around the entire construction site every day to make their contribution. This requires careful logistical planning. "Everything has to be delivered just-in-time," says Van Rees. "Furthermore, we work in different phases. The final phase of the control room and office facilities are now in the completion stage." The interior of the turbine building is being taken in hand by the client.