A pipe flocculator is a plug-flow type reactor used for chemical coagulation, flocculation, de-emulsification, pH correction, etc under well-defined conditions. In a pipe flocculator, the mixing energy required for chemical mixing is obtained by turbulence in the main pipe and mixing pipe. The retention time is almost uniform and mixing energy is constant in the pipe cross-section. As such, all particles will be subjected to the same amount of mixing energy for the same period, which will result in a highly uniform chemical mixing with excellent separation characteristics.
A coagulant is usually dosed with raw water/effluent at the inlet of the pipe flocculator. Immediately after the dosing point a mixing unit is installed for the mixing where the coagulant mixes with effluent. Mixing energy and reaction energy in the mixing unit and the pipe is a result of turbulence (Reynolds number).
Coagulation is the destabilization of the polluted matter in the raw water. Fine particles are formed, which are not ideal for separation. Flocculant has to be added to obtain separable particles. When the coagulation is completed a flocculant is dosed. The mixing of water and the flocculant takes place in a second mixing unit. Floc growth will further be completed in the pipe following the mixing unit. In this way a uniform, ideal floc can be formed for the separation of floc and water in a separator.
Application: chemical coagulation, flocculation, de-emulsification, pH correction
