Closure to 'Effects of Solid Levels and Chemical Additives on Removal of Solids and Phosphorus in Swine Manure' by Pius M. Ndegwa, Jun Zhu, and Ancheng Luo
| Autor: | Ancheng Luo, Pius M. Ndegwa, Jun Zhu |
|---|---|
| Rok vydání: | 2003 |
| Předmět: |
Flocculation
Suspended solids Environmental Engineering Waste management Sedimentation (water treatment) Alum Pulp and paper industry Dilution chemistry.chemical_compound chemistry Chemical addition Environmental Chemistry Water treatment General Environmental Science Civil and Structural Engineering Waste disposal |
| Zdroj: | Journal of Environmental Engineering. 129:487-487 |
| ISSN: | 1943-7870 0733-9372 |
| DOI: | 10.1061/(asce)0733-9372(2003)129:5(487) |
| Popis: | als then can be reckoned using the lower sedimentation tank volume in which the residuals are contained. Fig. 3 shows the results based on sedimentation data in the writers’ Fig. 2. It is seen that in the range of 1–2% dilution advocated by the writers, the final sludge concentration is much lower than the initial undiluted concentration. Hence, the objective of removing water from the swine waste so as to facilitate transport would not be achieved, and still more expenditure would be required to reconcentrate the residues back to their initial 6% value. Sedimentation performance data over a range of dilutions were not presented for swine waste treated with alum or ferric chloride. However, examination of the data from tests in which swine waste was diluted to 1% suspended solids and dosed with 1500 mg/L of alum or ferric chloride indicates that the same general conclusions from the sedimentation tests without chemicals ~Figs. 2 and 3! would be reached. Swine waste diluted to 1% suspended solids, treated with 1500 mg/L ferric chloride, and settled yielded sludge containing 2.8% suspended solids. With alum treatment, the final sludge suspended solids concentration was 3.2% ~for comparison, the settled sludge concentration was 2.5% when swine waste was diluted to 1% and settled without chemical addition, and the initial, undiluted, waste suspended solids concentration was 6%!. In calculations involving suspended solids in chemically treated waste, I ignored the mass of suspended chemical reaction products as, apparently, did the writers. In summary, dilution before treatment of the swine waste considered by the writers is not advisable. |
| Databáze: | OpenAIRE |
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