CHEMICAL TREATMENT
This section evaluates
different chemical compounds used for coagulation and flocculation processes. This
process reduces hardness and creates flocs that are a conglomeration of fine
pollutants, to reduce TSS by sedimentation.
Chemical Alternatives
The three alternatives considered as coagulants and flocculants were the following: aluminum sulfate, polyaluminum chloride, and aluminum chloride which can be seen below.
Figure 1: Chemical Structure of
Aluminum Sulfate
Figure 2: Chemical Structure of
Polyaluminum Chloride
Figure 3: Chemical Structure of
Aluminum Chloride
Chemical Treatment Scoring Criteria
Each alternative for chemical treatment was given a score from one to three. One being the least suitable alternative and three being the most suitable from the given criteria. The following table provides how each criteria was scored with the reasoning. It also provides the reasoning for the weighting of each criterion.
Table 1: Coagulation and Flocculation Scoring and Weighting Sheet
Chemical Treatment Decision Matrix
Using the scoring criteria for chemical treatment, the decision matrix for coagulation and flocculation was created to find the most suitable alternative for the treatment train. The decision matrix below is a simplified decision matrix, you can find the complete matrix in the final report, Appendix L: Scoring, Weighting, and Decision Matrix for Coagulation and Flocculation.
Table 2: Coagulation and Flocculation Simplified Decision Matrix
