Improvement of Quillón Sewage Treatment Plant

Description: This project corresponds to the improvement of the Quillón Wastewater Treatment Plant and aims to expand the capacity of the Treatment Plant, considering the projected demand by 2030, which is estimated at a population served of 5,426 inhabitants. To do this, it is necessary to modify the project "Construction of the Sewage Treatment Plant of the city of Quillón", qualified as environmentally friendly by means of SR No. 107 of April 15, 2002, of the Regional Commission for the Environment of the Biobío Region. The indicated exempt resolution is attached in Annex 2. Currently, the Sewage Treatment Plant consists of a process of activated sludge in the extended aeration mode. The treatment plant has a compact plant for pre-treatment that contains roughing, defatting and de-sanding. In addition, the PTAS includes a flow distribution chamber, a biological reactor with fine bubble diffusers, a secondary sedimentation tank, an aerated sludge accumulation tank, a contact chamber with a chlorine gas dosing system and a liquid lift plant. filtered. The effluent from the plant is discharged to Estero Quillón in compliance with the limits established in Table No. 1 of DS No. 90/2000 MINSEGPRES, emission standard for the regulation of pollutants associated with discharges of liquid waste to bodies of surface water . Currently, the sludge line includes the mechanical dewatering of sludge through band filter with addition of polymer. Once dehydrated, the unstabilized sludge is transferred for stabilization and sanitation to the "Cabrero sludge whitewashing shed" and then applied to the ground or derived to a sanitary and environmentally authorized disposal site. For the increase of the treatment capacity, the modifications to the Sewage Treatment Plant of Quillón subjected to environmental evaluation consist of converting the existing activated sludge treatment system to an activated sludge system with mobile bed of the MBBR type (Moving bed biofilm reactor) in conventional aeration mode, which allows, through the use of plastic supports in the reactors, to improve the degradation efficiency of organic matter. This technology is based on the growth of biomass, in the form of biofilm, in plastic supports that are in continuous movement in the biological reactor through the agitation generated by the aeration system. These supports are of small size but with a high specific surface per unit volume, which allows the growth of more biomass and effectiveness than that of the biological flocs of conventional reactors. In a complementary manner to the technological change described, the following modifications are contemplated, considering as a forecast period the year 2030. Water line. New affluent flow meter of electromagnetic type that will be located upstream of the pretreatment. New compact pre-treatment equipment, leaving the original as backup. This modification is already executed. New chamber of distribution of flow to reactors. This modification is already executed. Construction of a second reactor with thick bubble diffusers and MBBR system. The change of fine bubble diffusers by thick bubble diffusers is considered in the existing reactor. Increased capacity of the aeration system. Construction of a new chamber for the distribution of flow to settlers. Construction of a second settler. Capacity increase chlorination system. Construction of a new contact chamber identical to the existing one. Sludge line Modification of the RAS / WAS pump system. It is designed for the recirculation of pumps in 2 + 1 configuration and for sludge purging, pumps in 1 + 1 configuration. New sludge dewatering equipment. The current band filter is replaced by a screw press equipment. The dehydrated