Algunos proyectos expositivos en museos españoles

Further research into the advantages and disadvantages of these two coagulants should include jar tests at alkaline pH values. Dempsey et al (1985) have shown that PACl

performs better than alum for the removal of TOC at pHs

above the sweep floe zone, but this issue was not addressed

in the work presented here.

Also, the effect of temperature during coagulation needs to be researched, particularly relative to the

56

residual aluminum). Dempsey et al (1985) have mentioned

that PACl works better than alum at cold temperatures. This

is probably due to the slow hydrolysis reaction of alum at colder temperatures.

Some jar tests should be conducted without artificially

maintaining a constant pH. PACl is less acidic than alum and has less of an effect on solution pH than alum does. An evaluation of the coagulation of various types of organic carbon and various concentrations needs to be conducted. More extensive testing of real waters with PACl should be done.

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APPENDIX-ANALYTICAL RESULTS

PH Log Dose UV TOC THM Al

Alum, Fulvic Acid

4.5 -4.12 0.206 4.20 275 980 5.5 -4.12 0.123 2.46 158 129 6.5 -4.12 0.130 2.38 187 22 5.0 -4.12 0.115 1.94 — 255 6.0 -4.12 0.092 2.09 — 32 5.5 -4.35 0.158 3.77 181 340 5.5 -4.22 0.108 2.56 — 164 5.5 -4.05 0.114 2.39 — 184 5.5 -3.98 0.165 2.81 194 956 6.5 -4.35 0.197 5.15 365 915 6.5 -4.22 0.200 4.84 — 373 6.5 -4.05 0.108 2.53 — 97 6.5 -3.98 0.120 2.99 220 162 5.5 -4.22 0.127 2.81 183 89 5.5 -4.12 0.095 2.56 152 49 6.5 -4.22 0.205 5.09 264 254 6.5 -4.12 0.162 3.14 189 79

PAC1, Fulvic Acid

5.5 -5.00 0.213 4.75 352 380 5.5 -4.75 0.220 5.25 328 421 5.5 -4.50 0.220 5.09 322 649 5.5 -4.25 0.190 3.07 198 22 4.5 -4.35 0.115 3.37 256 51 5.0 -4.35 0.163 3.61 302 821 5.5 -4.35 0.135 3.69 345 100 6.0 -4.35 0.179 4.37 340 947 6.5 -4.35 0.216 5.26 374 880 7.0 -4.35 0.207 5.05 372 734 4.5 -4.60 0.175 3.80 277 119 4.5 -4.50 0.172 3.76 259 116 4.5 -4.20 0.180 3.46 290 386 4.5 -4.10 0.204 3.98 244 1243 5.5 -4.15 0.158 3.63 249 265 5.5 -4.05 0.154 2.36 200 675 5.0 -4.35 0.165 3.06 235 111 5.5 -3.95 0.135 2.05 143 12 5.5 -4.40 0.130 3.45 240 79 4.5 -4.30 0.213 3.38 278 265 4.5 -4.40 0.220 3.36 190 168 5.5 -4.35 0.163 2.75 228 123 4.5 -4.00 0.250 4.32 351 2592 4.5 -4.75 0.252 3.63 295 155

63

Alum, Raw Water

5.5 -4.35 0.123 3.21 254 118 5.5 -4.22 0.151 2.66 . 235 47 5.5 -4.12 0.095 2.23 194 25 5.5 -3.98 0.105 2.15 176 22 6.5 -4.22 0.165 3.92 284 425 6.5 -4.12 0.218 3.75 284 866 6.5 -4.05 0.184 3.26 243 166 6.5 -3.92 0.186 2.82 222 90

PAC1, Raw Water

4.5 -4.50 0.159 3.70 293 177 4.5 -4.35 0.178 3.33 261 691 4.5 -4.20 0.194 3.04 245 776 4.5 -4.10 0.105 2.73 270 1185 5.5 -3.85 0.132 1.84 199 83 5.5 -3.95 0.133 2.02 181 45 5.5 -4.20 0.138 2.60 215 41 5.5 -4.30 0.118 2.97 237 54

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