{"id":14230,"date":"2026-05-29T00:33:41","date_gmt":"2026-05-29T07:33:41","guid":{"rendered":"https:\/\/www.recyclemachine.net\/"},"modified":"2026-05-29T00:33:42","modified_gmt":"2026-05-29T07:33:42","slug":"como-dimensionar-o-tanque-de-separacao-de-esgoto-flutuante","status":"publish","type":"post","link":"https:\/\/www.recyclemachine.net\/pt\/como-dimensionar-o-tanque-de-separacao-de-esgoto-flutuante\/","title":{"rendered":"Como dimensionar um Tanque de Separa\u00e7\u00e3o por Flutua\u00e7\u00e3o para sua Linha de Reciclagem"},"content":{"rendered":"<p>Most sink-float separation tanks are bought on a single number \u2014 a target throughput in kg\/h \u2014 and that is exactly why so many of them underperform once real post-consumer material starts flowing. A tank that looks correctly sized on paper can still hand you contaminated flake, runaway water bills, or a sludge problem nobody planned for. Sizing a sink-float tank well means matching it to your <em>feedstock behavior<\/em>, your <em>purity target<\/em>, and the <em>machines on either side of it<\/em> \u2014 not just to a capacity figure. This guide walks through how to do that before you issue an RFQ.<\/p>\n<h2>What a sink-float tank actually does (and what it can\u2019t)<\/h2>\n<p>A sink-float separation tank \u2014 also called a float-sink tank, float washing tank, or floating washer \u2014 separates plastics purely by density relative to water (1.0 g\/cm\u00b3). Lighter-than-water polymers float and are skimmed off the surface; denser polymers and heavy contaminants sink and are dragged out at the bottom. There are no screens or sensors deciding the split \u2014 gravity and buoyancy do the work, which is why the tank is so reliable and cheap to run, and also why it has a hard limit.<\/p>\n<figure class=\"wp-block-table\">\n<table>\n<thead>\n<tr>\n<th>Material<\/th>\n<th>Densidade (g\/cm\u00b3)<\/th>\n<th>Behavior in water<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>PP<\/td>\n<td>0,90\u20130,92<\/td>\n<td>Floats<\/td>\n<\/tr>\n<tr>\n<td>PE (HDPE \/ LDPE)<\/td>\n<td>0.91\u20130.96<\/td>\n<td>Floats<\/td>\n<\/tr>\n<tr>\n<td>PS<\/td>\n<td>1.04\u20131.07<\/td>\n<td>Sinks<\/td>\n<\/tr>\n<tr>\n<td>abd\u00f4men<\/td>\n<td>1.04\u20131.07<\/td>\n<td>Sinks<\/td>\n<\/tr>\n<tr>\n<td>BICHO DE ESTIMA\u00c7\u00c3O<\/td>\n<td>1,38\u20131,40<\/td>\n<td>Sinks<\/td>\n<\/tr>\n<tr>\n<td>PVC (rigid)<\/td>\n<td>1.35\u20131.45<\/td>\n<td>Sinks<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/figure>\n<p>The takeaway for sizing: a water tank cleanly splits floaters (PP\/PE) from sinkers (PET\/PVC\/PS\/ABS), but it <strong>cannot<\/strong> separate two materials that both sink. PET and PVC have overlapping densities, so both go to the bottom together. If your spec calls for sub-50-ppm PVC in rPET, you will need an electrostatic or NIR polishing step <em>after<\/em> the tank \u2014 size for that now, not later.<\/p>\n<h2>Step 1: Profile your feedstock before anything else<\/h2>\n<p>The single most useful thing you can do before sizing is characterize what is actually entering the tank. Three variables matter most:<\/p>\n<ul>\n<li><strong>Polymer mix.<\/strong> A clean PP\/PE float stream behaves completely differently from a mixed rigid post-consumer stream. The wider the density spread you need to capture, the more separation passes you want.<\/li>\n<li><strong>Bulk density and form.<\/strong> Light film and fluff sit on the surface and need strong, well-placed paddles to submerge and convey; heavy rigid flake sinks fast and loads the bottom screw harder.<\/li>\n<li><strong>Contamination load.<\/strong> Paper labels, glue, sand, fines, and organic residue all end up in the water and the sludge. Heavy contamination is the main reason a tank that is \u201cbig enough\u201d on throughput still fails on purity.<\/li>\n<\/ul>\n<p>If you can, run a float-sink test on a representative sample in a bucket of water. It tells you your real float:sink ratio, which directly drives skimmer and bottom-discharge sizing.<\/p>\n<h2>Step 2: Fix your real throughput band \u2014 not your peak<\/h2>\n<p>Throughput should be expressed as a band tied to a specific material, not a single headline number. A tank rated \u201c2000 kg\/h\u201d on clean PP regrind will not hold that rate on wet, contaminated post-consumer PET, because residence time \u2014 how long each flake stays in the water \u2014 is what determines separation quality. Push material through too fast and floaters get dragged down before they surface.<\/p>\n<p>Como refer\u00eancia para planejamento, as bandas t\u00edpicas de bandas de tanque \u00fanico caem aproximadamente em:<\/p>\n<ul>\n<li><strong>300\u20131,500 kg\/h<\/strong> \u2014 linhas de lavagem de filme e garrafas, limpas a moderadamente contaminadas.<\/li>\n<li><strong>1,500\u20133,000 kg\/h<\/strong> \u2014 linhas de capacidade superior e fluxos p\u00f3s-consumidor altamente contaminados (geralmente um tanque de tr\u00eas fileiras, veja abaixo).<\/li>\n<li><strong>3,500\u20135,000 kg\/h<\/strong> \u2014 plantas industriais de garrafa a garrafa, tipicamente com m\u00faltiplos ou tanques de comprimento estendido.<\/li>\n<\/ul>\n<p>A capacidade real sempre depende da geometria da alimenta\u00e7\u00e3o, densidade em massa, contamina\u00e7\u00e3o e qu\u00e3o rigoroso \u00e9 seu objetivo de pureza \u2014 portanto, trate isso como pontos de partida para uma conversa de engenharia, n\u00e3o garantias.<\/p>\n<h2>Passo 3: Single-row vs triple-row \u2014 a decis\u00e3o que determina o espa\u00e7o ocupado<\/h2>\n<p>Esta \u00e9 geralmente a decis\u00e3o de dimensionamento real. Um tanque de fileira \u00fanica d\u00e1 a cada flocagem uma passagem pela \u00e1gua. Um <a href=\"https:\/\/www.recyclemachine.net\/pt\/tecnologia-avancada-de-separacao-de-boia-de-pia-de-tanque-de-tres-fileiras\/\">tanque de flutua\u00e7\u00e3o de tr\u00eas fileiras<\/a> faz o material viajar tr\u00eas vezes a dist\u00e2ncia e encharcar tr\u00eas vezes mais tempo em um chassi, o que permite alcan\u00e7ar uma pureza mais alta em alimenta\u00e7\u00e3o suja sem alinhar tr\u00eas tanques separados em s\u00e9rie.<\/p>\n<figure class=\"wp-block-table\">\n<table>\n<thead>\n<tr>\n<th>Crit\u00e9rios<\/th>\n<th>Tanque de fileira \u00fanica<\/th>\n<th>Tanque de tr\u00eas fileiras<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Banda de capacidade<\/td>\n<td>300\u20131,500 kg\/h<\/td>\n<td>1,000\u20133,000 kg\/h (um \u00fanico item substitui ~3 tanques de fileira \u00fanica em s\u00e9rie)<\/td>\n<\/tr>\n<tr>\n<td>Passagens de separa\u00e7\u00e3o<\/td>\n<td>1 passagem<\/td>\n<td>3 passagens \u2014 3\u00d7 maior dist\u00e2ncia de viagem e tempo de imers\u00e3o<\/td>\n<\/tr>\n<tr>\n<td>Pureza t\u00edpica<\/td>\n<td>98\u201399% em uma \u00fanica etapa<\/td>\n<td>99.5%+ mesmo na contamina\u00e7\u00e3o p\u00f3s-consumidor pesada<\/td>\n<\/tr>\n<tr>\n<td>Melhor insumo<\/td>\n<td>Regrind p\u00f3s-industrial limpo; flocagem de garrafas PET\/HDPE pr\u00e9-selecionadas<\/td>\n<td>PET p\u00f3s-consumidor pesadamente contaminado, pl\u00e1sticos r\u00edgidos misturados, WEEE, ASR automotivo<\/td>\n<\/tr>\n<tr>\n<td>Pot\u00eancia instalada<\/td>\n<td>~5.5\u201315 kW<\/td>\n<td>~15\u201322 kW<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/figure>\n<p>Regra das pontas: se o objetivo da sua linha for acima de 1,500 kg\/h, ou sua alimenta\u00e7\u00e3o vier de sacos de lixo de rua ou DRS, a configura\u00e7\u00e3o de tr\u00eas fileiras geralmente recupera seu pr\u00eamio dentro do primeiro ano atrav\u00e9s de aumento da pureza e de menos trocas de grade-filtro de extrusora no fluxo downstream.<\/p>\n<h2>Passo 4: Dimensione o ciclo de \u00e1gua e o manejo de lodo, n\u00e3o apenas o tanque<\/h2>\n<p>O tanque \u00e9 a parte barata. O sistema de \u00e1gua e lodo ao redor dele \u00e9 onde s\u00e3o ganhos ou perdidos os custos operacionais, e \u00e9 rotineiramente especificado de forma insuficiente.<\/p>\n<ul>\n<li><strong>Water consumption.<\/strong> Without a treatment loop, a tank typically draws 20\u201330 m\u00b3 of fresh water per ton of throughput. Adding a DAF (dissolved air flotation) and sedimentation loop typically cuts that to 3\u20135 m\u00b3 per ton \u2014 up to ~85% reuse. Over a year that difference dwarfs the price gap between tank models.<\/li>\n<li><strong>Sludge.<\/strong> Paper fiber, label glue, fines, and grit have to go somewhere. A dedicated screw press de-waters the sludge into a 60\u201370% solid cake that is cheap to haul away, instead of leaving you with a liquid-waste headache.<\/li>\n<\/ul>\n<p>Specify the water loop and sludge press <em>in the same RFQ<\/em> as the tank. Bolting them on afterward almost always costs more and fits worse.<\/p>\n<h2>Step 5: Place the tank correctly in the wash line<\/h2>\n<p>A sink-float tank is a separation stage, not a standalone machine. It needs the right feed condition coming in and the right handoff going out:<\/p>\n<ul>\n<li><strong>Upstream:<\/strong> material should already be size-reduced and pre-washed. A <a href=\"https:\/\/www.recyclemachine.net\/pt\/maquina-de-lavar-parafusos-de-friccao\/\">arruela de fric\u00e7\u00e3o<\/a> ou <a href=\"https:\/\/www.recyclemachine.net\/pt\/sistema-de-lavagem-a-quente-continuo-para-flocos-de-pet-e-hdpe\/\">hot wash system<\/a> ahead of the tank removes the bulk of glue and surface dirt so the float-sink split is clean.<\/li>\n<li><strong>Downstream:<\/strong> separated flake still carries water. Plan for dewatering and drying before pelletizing, and \u2014 if you are chasing food-grade rPET \u2014 the electrostatic or optical PVC-removal step mentioned earlier.<\/li>\n<\/ul>\n<p>If you are scoping a full line rather than a single machine, start from the <a href=\"https:\/\/www.recyclemachine.net\/pt\/reciclagem-de-sistemas-de-lavagem\/\">washing system<\/a> level and let the tank size fall out of the line target.<\/p>\n<h2>Quick-reference sizing checklist<\/h2>\n<p>Before you send an RFQ, have answers to these:<\/p>\n<ol>\n<li>What polymers are in the feed, and what is the approximate float:sink ratio?<\/li>\n<li>What is the realistic throughput band for <em>that<\/em> material \u2014 not your best-case peak?<\/li>\n<li>What purity does your buyer or extruder actually require?<\/li>\n<li>Is the feed clean post-industrial, or contaminated post-consumer? (This usually decides single- vs triple-row.)<\/li>\n<li>Are water reuse (DAF) and a sludge press included in the scope?<\/li>\n<li>What machine feeds the tank, and what machine receives the separated streams?<\/li>\n<\/ol>\n<h2>Five sizing mistakes that cost you later<\/h2>\n<ul>\n<li><strong>Sizing on peak kg\/h.<\/strong> Tempo de resid\u00eancia, n\u00e3o a capacidade da placa, determina a pureza. Tamanho para taxa sustentada na sua alimenta\u00e7\u00e3o mais suja realista.<\/li>\n<li><strong>Esperar que a \u00e1gua sozinha remova PVC do PET.<\/strong> Isso n\u00e3o pode ser feito \u2014 ambos afundam. Planeje a etapa de polimento desde o in\u00edcio.<\/li>\n<li><strong>Ignorar o ciclo de \u00e1gua.<\/strong> Um tanque sem DAF pode custar mais em \u00e1gua fresca e taxas de descarga do que o tanque em si.<\/li>\n<li><strong>Esquecer o lodo.<\/strong> Sem desidrata\u00e7\u00e3o, h\u00e1 um custo recorrente de res\u00edduo l\u00edquido e tempo de inatividade.<\/li>\n<li><strong>Comprar o tanque isoladamente.<\/strong> A lavagem upstream errada ou o secador downstream errado faz com que um tanque perfeitamente dimensionado pare\u00e7a que falhou.<\/li>\n<\/ul>\n<h2>Perguntas frequentes<\/h2>\n<h3>Um tanque de afundamento-flutua\u00e7\u00e3o pode separar completamente PET do PVC?<\/h3>\n<p>N\u00e3o. PET (1,38\u20131,40 g\/cm\u00b3) e PVC (1,35\u20131,45 g\/cm\u00b3) ambos afundam com densidades sobrepostas, ent\u00e3o um tanque de \u00e1gua os envia para o fundo juntos. Para PVC abaixo de 50 ppm em rPET, adicione um separador eletrost\u00e1tico ou classificador \u00f3ptico NIR como uma etapa de polimento ap\u00f3s o tanque.<\/p>\n<h3>Quanta \u00e1gua um tanque de afundamento-flutua\u00e7\u00e3o consome?<\/h3>\n<p>Tipicamente, 20\u201330 m\u00b3 de \u00e1gua fresca por tonelada sem filtra\u00e7\u00e3o. Com um DAF e ciclo de sedimenta\u00e7\u00e3o, isso geralmente cai para 3\u20135 m\u00b3 por tonelada (at\u00e9 ~85% reutiliza\u00e7\u00e3o), que \u00e9 onde a maioria da economia de custos operacionais vem.<\/p>\n<h3>Quando um tanque de tr\u00eas fileiras vale o custo extra?<\/h3>\n<p>Geralmente quando sua linha opera acima de ~1.500 kg\/h ou sua alimenta\u00e7\u00e3o \u00e9 material contaminado p\u00f3s-consumidor (lixo de rua, balas DRS, mistos r\u00edgidos). Os dois passos extras aumentam a pureza e reduzem as trocas de filtro downstream, geralmente pagando de volta dentro do primeiro ano.<\/p>\n<h3>Onde o tanque se situa na linha?<\/h3>\n<p>Ap\u00f3s a redu\u00e7\u00e3o de tamanho e pr\u00e9-lavagem\/fric\u00e7\u00e3o ou lavagem quente, e antes da desidrata\u00e7\u00e3o, secagem e pelotiza\u00e7\u00e3o. Alimenta\u00e7\u00e3o limpa significa divis\u00e3o limpa de flutua\u00e7\u00e3o-afundamento.<\/p>\n<p>Precisa de ajuda para combinar um tanque com sua alimenta\u00e7\u00e3o e objetivo de linha espec\u00edficos? Compartilhe sua mistura de pol\u00edmero, n\u00edvel de contamina\u00e7\u00e3o e objetivo de capacidade de produ\u00e7\u00e3o, e nossos engenheiros podem recomendar uma <a href=\"https:\/\/www.recyclemachine.net\/pt\/tanque-de-separacao-de-flutuacao-de-pia\/\">tanque de separa\u00e7\u00e3o afundamento-flutua\u00e7\u00e3o<\/a> configura\u00e7\u00e3o \u2014 \u00fanica ou de tr\u00eas fileiras, com o ciclo de \u00e1gua e manejo de lodo correto \u2014 dimensionada em torno do seu processo real em vez de um n\u00famero em destaque.<\/p>\n\n\n<p class=\"wp-block-paragraph\"><\/p>","protected":false},"excerpt":{"rendered":"<p>Um guia de dimensionamento pr\u00e1tico para tanques de separa\u00e7\u00e3o afundamento-flutua\u00e7\u00e3o: combine a capacidade de produ\u00e7\u00e3o, densidade da mat\u00e9ria-prima, configura\u00e7\u00e3o \u00fanica versus de tr\u00eas fileiras, e manejo de \u00e1gua e lodo antes de emitir uma solicita\u00e7\u00e3o de cota\u00e7\u00e3o.<\/p>","protected":false},"author":1,"featured_media":14234,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1997],"tags":[],"class_list":["post-14230","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-buying-guides"],"tsf_seo":{"title":"","description":"","robots":"index, follow","canonical":"","og_title":"","og_description":"","og_image":"","no_blogname":false},"_links":{"self":[{"href":"https:\/\/www.recyclemachine.net\/pt\/wp-json\/wp\/v2\/posts\/14230","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.recyclemachine.net\/pt\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.recyclemachine.net\/pt\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.recyclemachine.net\/pt\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.recyclemachine.net\/pt\/wp-json\/wp\/v2\/comments?post=14230"}],"version-history":[{"count":2,"href":"https:\/\/www.recyclemachine.net\/pt\/wp-json\/wp\/v2\/posts\/14230\/revisions"}],"predecessor-version":[{"id":14233,"href":"https:\/\/www.recyclemachine.net\/pt\/wp-json\/wp\/v2\/posts\/14230\/revisions\/14233"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.recyclemachine.net\/pt\/wp-json\/wp\/v2\/media\/14234"}],"wp:attachment":[{"href":"https:\/\/www.recyclemachine.net\/pt\/wp-json\/wp\/v2\/media?parent=14230"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.recyclemachine.net\/pt\/wp-json\/wp\/v2\/categories?post=14230"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.recyclemachine.net\/pt\/wp-json\/wp\/v2\/tags?post=14230"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}