Tronox operate an Ilmenite Reduction Kiln at their Chandala site. Coal is used as reductant and additional sulphur is added to the process. Exhaust gas from the kiln passes through an afterburner chamber and then into a venturi scrubber for particulate and SO2 removal.

The first stage of the scrubber is to quench the gas from around 1000°C. This is done by injecting liquor through a set of nozzles fed from a manifold.

Problems were experienced with the refractory design and Tronox decided to investigate options for an alternate design which could be installed during the 2014 plant shut.


Our starting point was to generate a model of the process based on our knowledge of the material, air and gas flows through the kiln obtained during our long involvement with Tronox. This enabled us to set accurate boundary constraints for the gas composition and mass flow into the quench.

The next stage was to model the conditions during the quench. The saturated gas conditions, gas velocities and liquor flow were calculated at each point of the gas passage through the scrubber.

Scale 3D CAD models of the existing system and of a new proposal for changes proposed by the Tronox team were then generated. The parameters were checked against standard practice and TES experience and velocities and flow patterns carefully reviewed.  This gave Tronox enough confidence to sign off on the concept and proceed to a detail design.

Since the new design had to fit into the existing site constraints including the structural supports, inlet and outlet ducts and the liquor supply points from pump to manifolds  we created a further 3D CAD model which included the structure and liquor supply pipes to make sure that all interfaces were correct. A full set of drawings for the new quench facility was prepared using the Tronox template to Tronox standards.

The complete manufacture and refractory installation was done off site. Careful planning was required by Tronox engineers to remove the old assembly and install the new one within the time constraints of the shut. The mass of the quench and installed refractory is approximately 30 tons. Our finite element analysis confirmed that there was sufficient margin of safety. After independent verification by a Tronox engineer  the design was confirmed to be acceptable.

Feedback from Tronox engineers is that the project is a success. Maintenance personnel report better access to nozzles than with the original design. Emission testing has confirmed that there has been no detrimental effect on the scrubber collection efficiency.