Dual benefit: Save water, gain fertilizer
Palm oil mills, which use the wet process for extracting oil, produce a large amount of process wastewater: so-called palm oil mill effluent (POME). It contains high concentrations of dissolved and undissolved organic substances. Strict environmental regulations and the goal of sustainable production require efficient POME concentration. This makes it possible to reliably separate water and solids. The recovered water reduces consumption during oil extraction and steam generation. The separated solids contain valuable nutrients such as nitrogen, phosphorous, and potassium and can be used as fertilizer. In this way, treatment combines resource conservation with economic benefits.
The silent brake on production: Fouling
FOULING UND SCALING
The biggest technical hurdle in evaporation-based POME concentration is the marked tendency to fouling. As the process temperature rises, the organic compounds and solids form hard, insulating deposits on the heating surfaces of conventional evaporators. The result is that heat transfer slows down, evaporator performance drops, and energy demand increases. The frequent, cost-intensive shutdowns for cleaning, which are required for maintaining production, drive up operating costs.
The solution: Permanent self-cleaning
Our Klaren MEE/MVR technology uses a fluidized bed of cleaning particles which circulate with the POME through the evaporator tubes and continuously clean the tube inner walls. Deposits are removed as soon as they start to appear; before they can form a layer that inhibits performance. This keeps the heat transfer rate and evaporator performance at consistently and reliably high levels. The result is a stable evaporation process with high water recovery rates. Because shutdowns for cleaning become a thing of the past, plant availability increases significantly. At the same time, the operating costs are reduced thanks to lower maintenance and energy expenses.
Technologies in harmony
The key advantage with regard to energy efficiency reveals itself when Klaren technology is combined with mechanical vapor recompression (MVR). The vapor produced in the evaporator is captured, mechanically compressed, and reused as a heating medium for the evaporation process. However, this highly efficient energy cycle only works if the heat transfer in the evaporator is kept at the highest possible level over the long term – which is precisely where the self-cleaning Klaren MEE/MVR system comes in.
