## 3 Results and Discussion
### Industrial-Scale Phase
#### 3.2.2 Chemical Parameters  
The WW generated by breweries contains both organic and inorganic contaminants, including nitrogen and phosphorus compounds. These forms exist because processed natural components are used in beer production. BOD\({}_{5}\), COD, TSS, N\({}_{\text{tot}}\), P\({}_{\text{tot}}\), and P-PO\({}_{4}\)\({}^{3-}\) were monitored to confirm the results obtained in lab-scale tests. The influent concentrations of organic contaminants are comparable to those reported in previous studies. During tests, the average removal for BOD\({}_{5}\), COD, and TSS was found to be 34.3%, 26.5%, and 86.8%, respectively (Figure 3a). The outcomes can be interpreted as positive and confirm the results obtained at the scale in similar previous studies [33; 34; 35]. Comparing the results with those obtained in a 14-day experiment, where three different coagulation agents were used to achieve the highest level of effectiveness in eliminating organic pollutants, the use of PAC allowed the removal of 50% of COD [9]. However, it is important to note that the concentration of COD at the intake in that study was 219 mg L\({}^{-1}\) compared to 3.544 mg L\({}^{-1}\) in the present work, and this could have influenced the more limited removal of organic matter. In other studies, [PERSON] et al. [36] estimated the effectiveness of the use of FeCl\({}_{3}\) with a non-ionic flocculant for BWW pre-treatment highlighting that almost 4-26 mg of COD were removed per mg of coagulant used, a value higher than the 1-3 mg of COD removed per mg of coagulant obtained in this work. This difference could be attributed to the different types of coagulants but also to the diverse composition of the BWW since a complete characterization of the water was not carried out. For this reason, in general, due to different conditions of testing and initial characteristics of the BWW, a quantitative comparison between different case studies remains difficult. [PERSON] et al. [35] tested sequential electrocoagulation and chemical coagulation, using aluminum sulfate, in order to increase the performance of the organic matter degradation process in BWW. They obtained a COD removal of 26%, in line with that obtained in the present study, where electrochemical treatment was not applied. In any case, the current effectiveness of the coagulation-floculation process therefore makes it necessary to post-treat the BWW at a municipal WWTP before it can be discharged into a surface water body. The effectiveness of an alum-based coagulation agent for the removal of organic contaminants from water was also confirmed by [PERSON] et al. [13], who successfully treated a high-strength BWW in lab-scale tests. During the monitoring, the average decrease efficiencies for the parameters Ntot, Ptot, and P-PO4\({}^{3-}\) were 51.8%, 95.5%, and 99.55%, respectively (Figure 3b). Results about phosphorous removal confirm preliminary evaluation in lab-scale tests, while nitrogen removal at the industrial scale was shown to be less effective. Future studies will further explore this aspect, which remains unclarified. However, the results obtained in the present study are higher than those reported in previous works in the literature [37; 38; 39; 40; 41; 42]. For instance, [PERSON] et al. [37] used AlCl\({}_{3}\) as a coagulant, obtaining a removal of Ntot  
Figure 3: (**a**) Removal of BOD\({}_{5}\), COD, and TSS, and (**b**) removal of Ntot, Ptot, and P-PO4\({}^{3-}\) as a function of the load fed. Dotted lines refer to the linear fitting of the data. REF indicates the average percentage of removal obtained in lab-scale tests. The bars represent the 95% confidence interval of the results from diverse analyses (n = 3) made on the same sample. and Ptot of 19.9% and 82.3%, respectively. The difference could be attributed to the diverse flocculant used: an organic one made from vegetable tannin was dosed in the study of [PERSON] et al. [37], different from the AAF tested in this work.