Flash mixing and flocculation are two fundamental steps in industrial and urban wastewater treatment plants (also known as UWWTP). Flash mixing, or rapid mixing, is achieved by adding chemicals to the water to facilitate the coagulation of solids. The duration of this process is key to the success of the entire purification process. Flocculation, on the other hand, is the phase following flash mixing, where, thanks to the reaction with a polymer solution, the particles to be removed thicken and agglomerate into flocs, which are then separated from the water through sedimentation.
In both phases, choosing the right agitators and impellers is crucial. At PRO-DO-MIX®, we have extensive experience in the field, thanks in part to successful cases like the Sulaibiya Wastewater Treatment and Reclamation Plant in Kuwait. This plant, on its own, provides 26% of Kuwait’s entire water supply, reducing the annual demand from non-potable sources from 142 million m3 to 26 million m3.
The Sulaibiya Wastewater Treatment and Reclamation Plant in Kuwait treats and purifies over 510,000 m3 of water daily, an impressive amount by Western standards. Kuwait is one of the countries with the least available drinking water and simultaneously the highest per capita water consumption, making the Sulaibiya plant one of the largest on the planet.
The plant in question had 2 flash mixing tanks with a volume of 90 m3 each and 4 flocculation chambers, each with a volume of 270 m3, higher than the European standards. For the flash mixing tanks, we designed and manufactured 2 vertical agitators, BPL.D5301.S.290/Y, paired with our high-efficiency impeller, 3PM-0030, suited for this phase. With a diameter of 3,000 mm and a high hydrodynamic profile, this impeller generates a high flow rate, optimizing time and energy consumption.
For the flocculation chambers, we provided 4 agitators of the BPR.30302.S.335/Y model, designed for flocculation in very large tanks. The high-efficiency 2PM-0650 impeller, with a 3,000 mm diameter, ensures optimal flocculation and very low energy consumption, minimizing mechanical stress on newly formed flocs. This allowed us to install a motor with only 3 kW, reducing maintenance activities and minimizing plant downtime.
All impellers for the plant are made by Duplex SAF2205 stainless steel, which ensures excellent resistance to erosion, pitting, and interstitial corrosion. This material boasts mechanical properties superior to regular stainless steel and excellent chemical resistance, allowing us to reduce blade thickness and minimize mechanical loads.
For more information:
Project: Sulaibiya Wastewater Treatment and Reclamation Plant
Main EPC : M/s. Mohammed Abdul Mohsen Al-Kharafi & Sons
EPC/consultant: M/s. Utilities Development Company Kuwait with Ionics Inc., USA / GE earlier and now Suez WTS, USA
Operator : Utilities Development Company Kuwait
Operation & Maintenance : Italba Services S.r.l. / Veolia
More details : www.udcsulaibiya.com
If you are looking for a customized solution for flash mixing and flocculation in your industrial or urban wastewater treatment plant, you can rely on PRO-DO-MIX®‘s experience and successful cases.
Three-blade impeller with high hydrodynamic profile. It is the “evolution” of Hurricane. Its internal velocity gradient, constant from the centre to the edge of the blade, allows the positioning of an impeller with large diameter very close to the bottom of the tank. That makes Evolution perfect for applications that require the mixer’s continuous operation during the total draw-off of the tank.
It can be manufactured with different diameters, 1650 to 3500 mm.
A completely disassemblable option is available as well, to ease the entering through the tank manhole.
Flocculant mixing system with two-blade impeller. Thanks to its high hydrodynamic profile with wide blade surface, has the highest flow rate at the lowest peripheral speed. This design is aimed to prevent the fluid coming out from one blade to immediately meet the second blade.
Therefore, it is perfect when managing very delicate applications, where the fluid needs to be handled very gently and carefully. That is why Premium is specific for flocculation.
It can be manufactured with different diameters, 800 to 3000 mm.
A completely disassemblable option is available as well, to ease the entering through the tank manhole.
