Bolted thickeners help achieve optimal water balance

Using a bolted thickener to de-water slurry may offer a number of benefits in achieving optimal water balance in a plant.

The fit-for-purpose dewatering solution is usually constructed in a specialised off-site facility and the whole tank can then be transported to a site. This makes it particularly suitable for remote sites and also ensures quicker and safer on-site assembly. The amount of on-site welding required for the installation of a bolted thickener is also much less than that required  in the construction of normal steel thickeners. These features all contribute to increased cost savings and improved quality control.

FLSmidth was recently contracted to provide four large bolted thickeners for a customer in Mozambique. The installation aims to help achieve optimal water balance in the plant in Mozambique.  The four thickeners include the company’s E-Volute feedwell technology which is designed to improve flow distribution, leading to lower flocculant consumption, better settling rates and improved overflow clarity for the optimal performance of the thickener. Two of the thickeners are designed to reduce water load on the filters allowing for a drier filter product, while the other two thickeners recover water from the plant tailings.

“The thickeners measure 45 m in diameter and will control the density of material to the belt filters, improving the plant’s output,” says FLSmidth GM for projects and account sales in sub-Saharan Africa and the Middle East, Howard Areington. “The design was based on the test work we conducted on the customer’s material, allowing us to determine the best thickener solution.”

In addition, FLSmidth has provided a significant portion of the coal preparation equipment to the project, including reflux classifier technology, pumps, screens and feeders.