{"id":1833,"date":"2014-11-04T09:02:40","date_gmt":"2014-11-04T09:02:40","guid":{"rendered":"http:\/\/boer.it\/?page_id=1833"},"modified":"2018-10-01T07:36:54","modified_gmt":"2018-10-01T07:36:54","slug":"activated-sludge-plants","status":"publish","type":"page","link":"https:\/\/boer.it\/en\/water-treatment-plants\/activated-sludge-plants\/","title":{"rendered":"Activated sludge plants"},"content":{"rendered":"<section  class='av_textblock_section av-jmpzdqvz-172aa6c2f74b1be87b8ee40ad65a2aae '   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/CreativeWork\" ><div class='avia_textblock'  itemprop=\"text\" ><h1 class=\"titles\"><span class=\"titleFirst\">Activated<\/span><span class=\"titleSecond\">sludge plants<\/span><\/h1>\n<\/div><\/section>\n<section  class='av_textblock_section av-av_textblock-0366cc7376be6c9e82a3e9cc8987b64f '   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/CreativeWork\" ><div class='avia_textblock'  itemprop=\"text\" ><p>Activated sludge plants are suitable for purifying residential waste water and industrial biological effluent.<\/p>\n<\/div><\/section>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-av_hr-2683186cf6c434c3fdebf44adb9dc21f\">\n#top .hr.hr-invisible.av-av_hr-2683186cf6c434c3fdebf44adb9dc21f{\nheight:20px;\n}\n<\/style>\n<div  class='hr av-av_hr-2683186cf6c434c3fdebf44adb9dc21f hr-invisible  avia-builder-el-2  el_after_av_textblock  el_before_av_one_third '><span class='hr-inner '><span class=\"hr-inner-style\"><\/span><\/span><\/div>\n<div  class='flex_column av-av_one_third-2a9015ff38129c418a3f2eafba3e9512 av_one_third  avia-builder-el-3  el_after_av_hr  el_before_av_one_third  first flex_column_div  '     ><style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-av_image-95b65d8a1774204038d227d81404c363\">\n.avia-image-container.av-av_image-95b65d8a1774204038d227d81404c363 img.avia_image{\nbox-shadow:none;\n}\n.avia-image-container.av-av_image-95b65d8a1774204038d227d81404c363 .av-image-caption-overlay-center{\ncolor:#ffffff;\n}\n<\/style>\n<div  class='avia-image-container av-av_image-95b65d8a1774204038d227d81404c363 av-styling- avia-align-center  avia-builder-el-4  avia-builder-el-no-sibling '   itemprop=\"image\" itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/ImageObject\" ><div class=\"avia-image-container-inner\"><div class=\"avia-image-overlay-wrap\"><a href=\"https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_1.jpg\" data-srcset=\"https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_1.jpg 768w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_1-80x80.jpg 80w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_1-300x300.jpg 300w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_1-36x36.jpg 36w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_1-180x180.jpg 180w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_1-705x705.jpg 705w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_1-120x120.jpg 120w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_1-450x450.jpg 450w\" data-sizes=\"(max-width: 768px) 100vw, 768px\" class='avia_image'  aria-label='Activated sludge plants'><img decoding=\"async\" fetchpriority=\"high\" class='wp-image-2407 avia-img-lazy-loading-not-2407 avia_image ' src=\"https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_1.jpg\" alt='Activated sludge plants' title='Activated sludge plants'  height=\"768\" width=\"768\"  itemprop=\"thumbnailUrl\" srcset=\"https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_1.jpg 768w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_1-80x80.jpg 80w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_1-300x300.jpg 300w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_1-36x36.jpg 36w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_1-180x180.jpg 180w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_1-705x705.jpg 705w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_1-120x120.jpg 120w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_1-450x450.jpg 450w\" sizes=\"(max-width: 768px) 100vw, 768px\" \/><\/a><\/div><\/div><\/div><\/div>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-av_one_third-862f0c8b97abc46405e90743a1c7ee0e\">\n.flex_column.av-av_one_third-862f0c8b97abc46405e90743a1c7ee0e{\nborder-radius:0px 0px 0px 0px;\npadding:0px 0px 0px 0px;\n}\n<\/style>\n<div  class='flex_column av-av_one_third-862f0c8b97abc46405e90743a1c7ee0e av_one_third  avia-builder-el-5  el_after_av_one_third  el_before_av_one_third  flex_column_div av-zero-column-padding  '     ><style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-av_image-fb6537e9eb645102ca784599101d89c2\">\n.avia-image-container.av-av_image-fb6537e9eb645102ca784599101d89c2 img.avia_image{\nbox-shadow:none;\n}\n.avia-image-container.av-av_image-fb6537e9eb645102ca784599101d89c2 .av-image-caption-overlay-center{\ncolor:#ffffff;\n}\n<\/style>\n<div  class='avia-image-container av-av_image-fb6537e9eb645102ca784599101d89c2 av-styling- avia-align-center  avia-builder-el-6  avia-builder-el-no-sibling '   itemprop=\"image\" itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/ImageObject\" ><div class=\"avia-image-container-inner\"><div class=\"avia-image-overlay-wrap\"><a href=\"https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_3.jpg\" data-srcset=\"https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_3.jpg 768w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_3-80x80.jpg 80w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_3-300x300.jpg 300w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_3-36x36.jpg 36w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_3-180x180.jpg 180w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_3-705x705.jpg 705w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_3-120x120.jpg 120w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_3-450x450.jpg 450w\" data-sizes=\"(max-width: 768px) 100vw, 768px\" class='avia_image'  aria-label='Activated sludge plants'><img decoding=\"async\" fetchpriority=\"high\" class='wp-image-2570 avia-img-lazy-loading-not-2570 avia_image ' src=\"https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_3.jpg\" alt='Activated sludge plants' title='Activated sludge plants'  height=\"768\" width=\"768\"  itemprop=\"thumbnailUrl\" srcset=\"https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_3.jpg 768w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_3-80x80.jpg 80w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_3-300x300.jpg 300w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_3-36x36.jpg 36w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_3-180x180.jpg 180w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_3-705x705.jpg 705w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_3-120x120.jpg 120w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_3-450x450.jpg 450w\" sizes=\"(max-width: 768px) 100vw, 768px\" \/><\/a><\/div><\/div><\/div><\/div>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-av_one_third-862f0c8b97abc46405e90743a1c7ee0e\">\n.flex_column.av-av_one_third-862f0c8b97abc46405e90743a1c7ee0e{\nborder-radius:0px 0px 0px 0px;\npadding:0px 0px 0px 0px;\n}\n<\/style>\n<div  class='flex_column av-av_one_third-862f0c8b97abc46405e90743a1c7ee0e av_one_third  avia-builder-el-7  el_after_av_one_third  el_before_av_hr  flex_column_div av-zero-column-padding  '     ><style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-av_image-fdb112d442742c27e0b4f55d6f733277\">\n.avia-image-container.av-av_image-fdb112d442742c27e0b4f55d6f733277 img.avia_image{\nbox-shadow:none;\n}\n.avia-image-container.av-av_image-fdb112d442742c27e0b4f55d6f733277 .av-image-caption-overlay-center{\ncolor:#ffffff;\n}\n<\/style>\n<div  class='avia-image-container av-av_image-fdb112d442742c27e0b4f55d6f733277 av-styling- avia-align-center  avia-builder-el-8  avia-builder-el-no-sibling '   itemprop=\"image\" itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/ImageObject\" ><div class=\"avia-image-container-inner\"><div class=\"avia-image-overlay-wrap\"><a href=\"https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_2.jpg\" data-srcset=\"https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_2.jpg 768w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_2-80x80.jpg 80w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_2-300x300.jpg 300w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_2-36x36.jpg 36w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_2-180x180.jpg 180w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_2-705x705.jpg 705w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_2-120x120.jpg 120w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_2-450x450.jpg 450w\" data-sizes=\"(max-width: 768px) 100vw, 768px\" class='avia_image'  aria-label='Activated sludge plants'><img decoding=\"async\" fetchpriority=\"high\" class='wp-image-2409 avia-img-lazy-loading-not-2409 avia_image ' src=\"https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_2.jpg\" alt='Activated sludge plants' title='Activated sludge plants'  height=\"768\" width=\"768\"  itemprop=\"thumbnailUrl\" srcset=\"https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_2.jpg 768w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_2-80x80.jpg 80w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_2-300x300.jpg 300w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_2-36x36.jpg 36w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_2-180x180.jpg 180w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_2-705x705.jpg 705w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_2-120x120.jpg 120w, https:\/\/boer.it\/wp-content\/uploads\/2014\/06\/Impianti_a_fanghi_attivi_2-450x450.jpg 450w\" sizes=\"(max-width: 768px) 100vw, 768px\" \/><\/a><\/div><\/div><\/div><\/div>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-av_hr-ee2847e2e025ce3d30801259a03f9fd4\">\n#top .hr.hr-invisible.av-av_hr-ee2847e2e025ce3d30801259a03f9fd4{\nheight:10px;\n}\n<\/style>\n<div  class='hr av-av_hr-ee2847e2e025ce3d30801259a03f9fd4 hr-invisible  avia-builder-el-9  el_after_av_one_third  el_before_av_heading '><span class='hr-inner '><span class=\"hr-inner-style\"><\/span><\/span><\/div>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-av_heading-221bc17008107f86cdb133b332116da1\">\n#top .av-special-heading.av-av_heading-221bc17008107f86cdb133b332116da1{\npadding-bottom:5px;\nfont-size:24px;\n}\nbody .av-special-heading.av-av_heading-221bc17008107f86cdb133b332116da1 .av-special-heading-tag .heading-char{\nfont-size:25px;\n}\n#top #wrap_all .av-special-heading.av-av_heading-221bc17008107f86cdb133b332116da1 .av-special-heading-tag{\nfont-size:24px;\n}\n.av-special-heading.av-av_heading-221bc17008107f86cdb133b332116da1 .av-subheading{\nfont-size:15px;\n}\n\n@media only screen and (min-width: 480px) and (max-width: 767px){ \n#top #wrap_all .av-special-heading.av-av_heading-221bc17008107f86cdb133b332116da1 .av-special-heading-tag{\nfont-size:0.8em;\n}\n}\n\n@media only screen and (max-width: 479px){ \n#top #wrap_all .av-special-heading.av-av_heading-221bc17008107f86cdb133b332116da1 .av-special-heading-tag{\nfont-size:0.8em;\n}\n}\n<\/style>\n<div  class='av-special-heading av-av_heading-221bc17008107f86cdb133b332116da1 av-special-heading-h3 blockquote modern-quote  avia-builder-el-10  el_after_av_hr  el_before_av_textblock  av-inherit-size'><h3 class='av-special-heading-tag'  itemprop=\"headline\"  >Process description<\/h3><div class=\"special-heading-border\"><div class=\"special-heading-inner-border\"><\/div><\/div><\/div>\n<section  class='av_textblock_section av-av_textblock-0366cc7376be6c9e82a3e9cc8987b64f '   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/CreativeWork\" ><div class='avia_textblock'  itemprop=\"text\" ><p>Residential discharge treatment includes the following stages:<\/p>\n<p><span class=\"indice\">PRIMARY DECANTATION<\/span> in an Imhoff tank, to retain floating material and any settleable solids and obtain a partially clarified effluent with pollutant load cut by approx. 30%. Suds is pretreated in a fat condensation tank.<\/p>\n<p><span class=\"indice\">BIOLOGICAL OXIDATION<\/span> in the oxidation tank, where the sewage comes in contact with microorganisms that, in the presence of oxygene provided by high-efficiency submersible aerators, transform organic matter into stable matter. Pollutant load reduction rate, which highly depends on active sludge concentration in the tank, on the organic load and on retention time, can reach 98% in this stage. In addition to providing top performance and high durability, the ultra-low-noise submersible aerators do not require external cabinets.<\/p>\n<p><span class=\"indice\">FINAL DECANTATION<\/span> in a hopper chamber, in which sludge descends towards the bottom of the tank and purified water flows, along the overflow channel, into the sampling well, before merging with the receiving water body.<\/p>\n<p>The settled sludge is then recovered and recycled in the oxidation tank.<\/p>\n<p>If water is discharged into the ground, or within a sensitive area, it is recommendable to install a pre-denitrification tank upstream the oxidation tank, so that the denitrifying bacteria that develop in the same can reduce the level of nitrate in waste water, making it suitable for discharge.<\/p>\n<p>Specific pretreatment, according to type, is applied to biological industrial waste purified in activated sludge plants.<\/p>\n<p>The options are designed and built to suit different load standards:<\/p>\n<ul>\n<li>single-unit plants, with a single tank (monolitic on request) holding both the oxidation and decantation chamber separated by a party wall<\/li>\n<li>parallel-module plants, which can be activated separately, and are hence ideal for systems to be used before the maximum load they are designed for is reached<\/li>\n<li>industrial plants including pretreatment and special equipment according to type of waste water to be purified<\/li>\n<\/ul>\n<p>Custom start-up and running programs provided on request.<\/p>\n<\/div><\/section>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-av_heading-cedaaa6ccceb19852effb0ed37dcbe1a\">\n#top .av-special-heading.av-av_heading-cedaaa6ccceb19852effb0ed37dcbe1a{\npadding-bottom:5px;\nfont-size:24px;\n}\nbody .av-special-heading.av-av_heading-cedaaa6ccceb19852effb0ed37dcbe1a .av-special-heading-tag .heading-char{\nfont-size:25px;\n}\n#top #wrap_all .av-special-heading.av-av_heading-cedaaa6ccceb19852effb0ed37dcbe1a .av-special-heading-tag{\nfont-size:24px;\n}\n.av-special-heading.av-av_heading-cedaaa6ccceb19852effb0ed37dcbe1a .av-subheading{\nfont-size:15px;\n}\n\n@media only screen and (min-width: 480px) and (max-width: 767px){ \n#top #wrap_all .av-special-heading.av-av_heading-cedaaa6ccceb19852effb0ed37dcbe1a .av-special-heading-tag{\nfont-size:0.8em;\n}\n}\n\n@media only screen and (max-width: 479px){ \n#top #wrap_all .av-special-heading.av-av_heading-cedaaa6ccceb19852effb0ed37dcbe1a .av-special-heading-tag{\nfont-size:0.8em;\n}\n}\n<\/style>\n<div  class='av-special-heading av-av_heading-cedaaa6ccceb19852effb0ed37dcbe1a av-special-heading-h3 blockquote modern-quote  avia-builder-el-12  el_after_av_textblock  el_before_av_textblock  av-inherit-size'><h3 class='av-special-heading-tag'  itemprop=\"headline\"  >Running and maintenance<\/h3><div class=\"special-heading-border\"><div class=\"special-heading-inner-border\"><\/div><\/div><\/div>\n<section  class='av_textblock_section av-av_textblock-0366cc7376be6c9e82a3e9cc8987b64f '   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/CreativeWork\" ><div class='avia_textblock'  itemprop=\"text\" ><p>The plants do not require special maintenance. Adequately sized galvanized manholes, positioned right above the equipment, make running operations easier. However, it is recommendable to periodically monitor activated sludge evolution and the degree of treatment efficiency. The essential operations to be carried out following start-up are:<\/p>\n<ol>\n<li>periodical biological sludge concentration and treatment process check<\/li>\n<li>periodical check of the timer clock controlling blower and recirculation pump operation<\/li>\n<li>periodical removal of excessive sludge and pretreatment chamber cleaning<\/li>\n<\/ol>\n<p>The plant exploits microorganisms, therefore users must absolutely avoid harmful substances able to hamper the evolution of the same.<\/p>\n<p>Also high temperature, substantial variation in organic load and power outage, with consequent lack of biomass oxygenation, can affect microorganism evolution, and hence the degree of efficiency of the treatment.<\/p>\n<\/div><\/section>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-av_heading-38507b1139ac72a57200d743a2d9edf2\">\n#top .av-special-heading.av-av_heading-38507b1139ac72a57200d743a2d9edf2{\npadding-bottom:5px;\nfont-size:24px;\n}\nbody .av-special-heading.av-av_heading-38507b1139ac72a57200d743a2d9edf2 .av-special-heading-tag .heading-char{\nfont-size:25px;\n}\n#top #wrap_all .av-special-heading.av-av_heading-38507b1139ac72a57200d743a2d9edf2 .av-special-heading-tag{\nfont-size:24px;\n}\n.av-special-heading.av-av_heading-38507b1139ac72a57200d743a2d9edf2 .av-subheading{\nfont-size:15px;\n}\n\n@media only screen and (min-width: 480px) and (max-width: 767px){ \n#top #wrap_all .av-special-heading.av-av_heading-38507b1139ac72a57200d743a2d9edf2 .av-special-heading-tag{\nfont-size:0.8em;\n}\n}\n\n@media only screen and (max-width: 479px){ \n#top #wrap_all .av-special-heading.av-av_heading-38507b1139ac72a57200d743a2d9edf2 .av-special-heading-tag{\nfont-size:0.8em;\n}\n}\n<\/style>\n<div  class='av-special-heading av-av_heading-38507b1139ac72a57200d743a2d9edf2 av-special-heading-h3 blockquote modern-quote  avia-builder-el-14  el_after_av_textblock  el_before_av_textblock  av-inherit-size'><h3 class='av-special-heading-tag'  itemprop=\"headline\"  >Products<\/h3><div class=\"special-heading-border\"><div class=\"special-heading-inner-border\"><\/div><\/div><\/div>\n<section  class='av_textblock_section av-av_textblock-0366cc7376be6c9e82a3e9cc8987b64f '   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/CreativeWork\" ><div class='avia_textblock'  itemprop=\"text\" ><p>Plants for up to 80 PE (except for the 40 PE option) are made up by a single concrete tank con- taining a partition defining two chambers (oxidation and decantation). Sludge is recirculated by means of a timer pump, or of a Venturi tube in smaller plants. As recirculation frequency, and hence flow, can be modulated, the system is more versatile and adjusts to load variations. Ventilation is provided by submersible aerators. In plants for loads from 100 PE on, the decan- tation chamber is housed in a separate tank, while 175 to 400 PE plants (except for the 200 PE option) are constituted of different parallel modules.<\/p>\n<\/div><\/section>\n\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-av_hr-2683186cf6c434c3fdebf44adb9dc21f\">\n#top .hr.hr-invisible.av-av_hr-2683186cf6c434c3fdebf44adb9dc21f{\nheight:20px;\n}\n<\/style>\n<div  class='hr av-av_hr-2683186cf6c434c3fdebf44adb9dc21f hr-invisible  avia-builder-el-16  el_after_av_textblock  el_before_av_button '><span class='hr-inner '><span class=\"hr-inner-style\"><\/span><\/span><\/div>\n<div  class='avia-button-wrap av-av_button-42d1d3b4b0bf2a0e32c4ec55e8e4b00c-wrap avia-button-left  avia-builder-el-17  el_after_av_hr  avia-builder-el-last '><a href='http:\/\/boer.it\/wp-content\/uploads\/2014\/11\/08_activated_sludge_plants.pdf'  class='avia-button av-av_button-42d1d3b4b0bf2a0e32c4ec55e8e4b00c avia-icon_select-yes-left-icon avia-size-small avia-position-left avia-color-theme-color-subtle'  ><span class='avia_button_icon avia_button_icon_left' aria-hidden='true' data-av_icon='\ue823' data-av_iconfont='entypo-fontello'><\/span><span class='avia_iconbox_title' >Technical Data Sheet PDF<\/span><\/a><\/div>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":1,"featured_media":0,"parent":1711,"menu_order":0,"comment_status":"open","ping_status":"open","template":"","meta":{"footnotes":""},"class_list":["post-1833","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/boer.it\/en\/wp-json\/wp\/v2\/pages\/1833","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/boer.it\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/boer.it\/en\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/boer.it\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/boer.it\/en\/wp-json\/wp\/v2\/comments?post=1833"}],"version-history":[{"count":2,"href":"https:\/\/boer.it\/en\/wp-json\/wp\/v2\/pages\/1833\/revisions"}],"predecessor-version":[{"id":4614,"href":"https:\/\/boer.it\/en\/wp-json\/wp\/v2\/pages\/1833\/revisions\/4614"}],"up":[{"embeddable":true,"href":"https:\/\/boer.it\/en\/wp-json\/wp\/v2\/pages\/1711"}],"wp:attachment":[{"href":"https:\/\/boer.it\/en\/wp-json\/wp\/v2\/media?parent=1833"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}