A CST Wastewater STU/CR combined inlet screen and grit removal package plant has been installed as part of a sewage treatment system in New Zealand.
The town of Te Aroha on the North Island previously used oxidation ponds to handle the effluent. Now the treatment process culminates with a Membrane Biological Reactor (MBR). The ponds have been retained for stormwater storage.
The Matamata-Piako District Council, servicing a municipality of 4000 people, commissioned the upgrade in 2006. It says it is the third or fourth council in the country to install a MBR.
According to the company, the council examined the performance of the screen and grit removal system. It found that there was only a small amount of fibrous material in the water and tiny particles in the sludge at the bottom of the tanks.
The system is designed to remove 95% of particles above 250µm in size. The council’s analysis found a median particle size of 100µm. This ensures that the MBR does not get blocked.
The STU/CR plant uses a stainless steel tank and a shaft-less spiral screw made from micro-alloy carbon steel. It can handle flowrates up to 200L per seconds.
Add your comments