title: Reversing clogging in subsurface-flow constructed wetlands by hydrogen peroxide treatment: two case studies.
abstract: One of the most frequently encountered operational problems in subsurface-flow constructed wetlands is clogging. Traditionally, the restoration procedure is to remove the clogged gravel or sand and replace it with clean material. This method, while effective, is costly and may require sections of the facility to be taken offline for extended periods of time. Another common remediation strategy is to have a resting period for each wetland cell, although this is not an option for very small systems which often consist of only one treatment cell. Recently, a more radical approach has been tested on a number of lab-scale and pilot-scale setups which consists of an aggressive oxidation of organic matter by means of hydrogen peroxide (H(2)O(2)). Results indicate that after treatment, clogging was substantially reduced and that H(2)O(2) did not appear to have a long-term negative effect on plants and biofilms. The outcomes of two full-scale tests are discussed in this paper.
authors.affiliation: Jacques Whitford NAWE, 4444 Centerville Road, White Bear Lake, Minnesota 55127, USA; Current address: Helmholtz Centre for Environmental Research (UFZ), Permoserstrasse 15, 04318 Leipzig, Germany. jaime.nivala@gmail.com
authors.forename: Jaime
authors.initials: J
authors.lastname: Nivala
authors.forename: Diederik P L
authors.initials: DP
authors.lastname: Rousseau
mesh_terms: D001530:Belgium; D052918:Environmental Restoration and Remediation / Q000379:methods; D006861:Hydrogen Peroxide; D019684:Magnoliopsida / Q000254:growth & development; D008910:Minnesota; D010084:Oxidation-Reduction; D010865:Pilot Projects; D012449:Safety; D012722:Sewage / Q000032:analysis; D014865:Waste Disposal, Fluid / Q000379:methods* / Q000592:standards; D014872:Water Movements; D018508:Water Purification / Q000379:methods*
chemical_list: D012722:Sewage; D006861:Hydrogen Peroxide