Digestate 1: Scaling control approach
NuReSys references applications on Digestate / Scaling control
· Nieuwegein The Netherlands MWWTP (under construction)
Operational October 2016
The second approach directly applied on digested sludge is illustrated below. This is full option NuReSys technology: Stripper Reactor for pH control and stirred tank Crytalizing Reactor with MgCl2 addition to promote active struvite formation. Main advantages are again scaling prevention (based on limiting free soluble phosphate) and improvement of dewatering of the bio solids. This dewatering improvement is relevant but needs to be correctly evaluated. The noticed gain in dry matter is significantly due to struvite formation as such and has nothing in common with improved dewater ability. NuReSys was the first to a certain this and straighten this general misconception. Another major advantage is reducing the phosphorus load returning to the head of the MWTP. The option of either harvesting the struvite or not (struvite retained in the dewatered bio solids) is again case dependent. Again the NuReSys technology has the flexibility to implement harvesting or not still ensuring the previously mentioned advantages.