title: Quick-start of full-scale anaerobic digestion (AD) using aeration.
abstract: A conventional 1300 m(3) continuously stirred anaerobic tank reactor at the city of Boden, north Sweden, which was receiving a feed of both sewage sludge and food waste, was put out of operation due to the build-up of a float phase. The reactor was emptied and cleaned. At start-up there was no methanogenic sludge available, so an unconventional start-up procedure was applied: The reactor was rapidly (8 days with 1200 kg of total solids (TS) added daily) filled with thickened, and slightly acidic sewage sludge, showing only slight methane generation, which was subsequently heated to 55 °C. Then compressed air was blown into the digester and within a month a fully functional methanogenic culture was established. The transfer from acidogenic to methanogenic conditions happened in about one week. As a start-up technique this is fast and cost efficient, it only requires the access of a compressor, electricity and a source of air. In total, about 16 tonnes of oxygen were used. It is proposed that this method may also be used as an operational amendment technique, should a reactor tend to acidify.
authors: Waste Science and Technology, Luleå University of Technology, 97187 Luleå, Sweden. Electronic address: al@ltu.se.
authors: Anders
authors: A
authors: Lagerkvist
authors: Waste Science and Technology, Luleå University of Technology, 97187 Luleå, Sweden.
authors: Markku
authors: M
authors: Pelkonen
authors: Waste Science and Technology, Luleå University of Technology, 97187 Luleå, Sweden.
authors: Tommy
authors: T
authors: Wikström
mesh_terms: D000693:Anaerobiosis; D019149:Bioreactors; D012037:Refuse Disposal / Q000379:methods*; D062611:Solid Waste / Q000032:analysis*; D013548:Sweden
chemical_list: D062611:Solid Waste
keywords: Anaerobic digestion; Food-waste; Methanogens; Sewage sludge; Start-up