{"id":31042,"date":"2026-07-04T22:19:55","date_gmt":"2026-07-04T14:19:55","guid":{"rendered":"https:\/\/shchimay.com\/inline-ph-electrode-technology-for-acid-mine-drainage-treatment-the-shanghai-chimay-overview\/"},"modified":"2026-07-04T22:19:55","modified_gmt":"2026-07-04T14:19:55","slug":"inline-ph-electrode-technology-for-acid-mine-drainage-treatment-the-shanghai-chimay-overview","status":"publish","type":"post","link":"https:\/\/shchimay.com\/pt\/inline-ph-electrode-technology-for-acid-mine-drainage-treatment-the-shanghai-chimay-overview\/","title":{"rendered":"Inline pH Electrode Technology for Acid Mine Drainage Treatment: The Shanghai ChiMay Overview"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_50 counter-hierarchy ez-toc-counter ez-toc-light-blue ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-1'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/shchimay.com\/pt\/inline-ph-electrode-technology-for-acid-mine-drainage-treatment-the-shanghai-chimay-overview\/#Inline_pH_Electrode_Technology_for_Acid_Mine_Drainage_Treatment_The_Shanghai_ChiMay_Overview\" title=\"Inline pH Electrode Technology for Acid Mine Drainage Treatment: The Shanghai ChiMay Overview\">Inline pH Electrode Technology for Acid Mine Drainage Treatment: The Shanghai ChiMay Overview<\/a><ul class='ez-toc-list-level-2'><li class='ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/shchimay.com\/pt\/inline-ph-electrode-technology-for-acid-mine-drainage-treatment-the-shanghai-chimay-overview\/#Why_AMD_Is_So_Hard_on_pH_Sensors\" title=\"Why AMD Is So Hard on pH Sensors\">Why AMD Is So Hard on pH Sensors<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/shchimay.com\/pt\/inline-ph-electrode-technology-for-acid-mine-drainage-treatment-the-shanghai-chimay-overview\/#The_Inline_Electrode_Approach\" title=\"The Inline Electrode Approach\">The Inline Electrode Approach<\/a><ul class='ez-toc-list-level-3'><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/shchimay.com\/pt\/inline-ph-electrode-technology-for-acid-mine-drainage-treatment-the-shanghai-chimay-overview\/#1_Double-Junction_Reference\" title=\"1. Double-Junction Reference\">1. Double-Junction Reference<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/shchimay.com\/pt\/inline-ph-electrode-technology-for-acid-mine-drainage-treatment-the-shanghai-chimay-overview\/#2_Heavy-Duty_Glass_Bulb_with_Self-Cleaning_Geometry\" title=\"2. Heavy-Duty Glass Bulb with Self-Cleaning Geometry\">2. Heavy-Duty Glass Bulb with Self-Cleaning Geometry<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/shchimay.com\/pt\/inline-ph-electrode-technology-for-acid-mine-drainage-treatment-the-shanghai-chimay-overview\/#3_Robust_Mechanical_Body\" title=\"3. Robust Mechanical Body\">3. Robust Mechanical Body<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/shchimay.com\/pt\/inline-ph-electrode-technology-for-acid-mine-drainage-treatment-the-shanghai-chimay-overview\/#Where_Inline_pH_Goes_in_an_AMD_Treatment_Train\" title=\"Where Inline pH Goes in an AMD Treatment Train\">Where Inline pH Goes in an AMD Treatment Train<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/shchimay.com\/pt\/inline-ph-electrode-technology-for-acid-mine-drainage-treatment-the-shanghai-chimay-overview\/#Calibration_Strategy\" title=\"Calibration Strategy\">Calibration Strategy<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/shchimay.com\/pt\/inline-ph-electrode-technology-for-acid-mine-drainage-treatment-the-shanghai-chimay-overview\/#Integration_with_Lime_Dosing_Control\" title=\"Integration with Lime Dosing Control\">Integration with Lime Dosing Control<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/shchimay.com\/pt\/inline-ph-electrode-technology-for-acid-mine-drainage-treatment-the-shanghai-chimay-overview\/#Operator_Habits_That_Make_or_Break_the_Installation\" title=\"Operator Habits That Make or Break the Installation\">Operator Habits That Make or Break the Installation<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/shchimay.com\/pt\/inline-ph-electrode-technology-for-acid-mine-drainage-treatment-the-shanghai-chimay-overview\/#Closing_Thoughts\" title=\"Closing Thoughts\">Closing Thoughts<\/a><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n<h1 id=\"inline-ph-electrode-technology-for-acid-mine-drainage-treatment-the-shanghai-chimay-overview\"><span class=\"ez-toc-section\" id=\"Inline_pH_Electrode_Technology_for_Acid_Mine_Drainage_Treatment_The_Shanghai_ChiMay_Overview\"><\/span>Inline pH Electrode Technology for Acid Mine Drainage Treatment: The Shanghai ChiMay Overview<span class=\"ez-toc-section-end\"><\/span><\/h1>\n<p>Acid mine drainage, or AMD, is one of the most stubborn water-quality problems in the global mining industry. It forms when sulfide minerals such as pyrite are exposed to oxygen and water, producing sulfuric acid and dissolved metals that can devastate downstream rivers and aquifers. Effective neutralization of AMD almost always relies on lime dosing, and the entire control loop for that dosing depends on one humble piece of hardware: a rugged pH electrode that survives in some of the harshest water any sensor will ever see. This overview from Shanghai ChiMay engineers explains how a modern inline pH electrode is designed, why traditional probes fail in mining service, and what specifying the right technology looks like in practice.<\/p>\n<h2 id=\"why-amd-is-so-hard-on-ph-sensors\"><span class=\"ez-toc-section\" id=\"Why_AMD_Is_So_Hard_on_pH_Sensors\"><\/span>Why AMD Is So Hard on pH Sensors<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>A typical AMD stream is not just acidic \u2014 pH values of 2 to 4 are common, and some pit-bottom waters fall below pH 2. The water also carries dissolved iron, aluminum, manganese, copper, and zinc at levels that can reach hundreds of milligrams per liter. Suspended solids from weathered rock, biofilms from acidophilic bacteria, and dissolved sulfates round out the cocktail. Each of these constituents attacks a pH electrode in a different way:<\/p>\n<ul>\n<li>Strong acidity strips the hydration gel layer on the pH-sensitive glass faster than in neutral service, shortening calibration intervals.<\/li>\n<li>Iron and manganese can precipitate as oxides on the electrode surface when local pH rises near a lime injection point.<\/li>\n<li>Sulfates can foul the reference junction, shifting the measured potential.<\/li>\n<li>Suspended solids and biofilms coat the glass, causing slow response.<\/li>\n<\/ul>\n<p>A pH probe that lasts twelve months in a city drinking-water plant may give up after three or four weeks in an AMD pit if the wrong technology is used.<\/p>\n<h2 id=\"the-inline-electrode-approach\"><span class=\"ez-toc-section\" id=\"The_Inline_Electrode_Approach\"><\/span>The Inline Electrode Approach<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>The Shanghai ChiMay inline pH electrode is built specifically for installation in a process pipe or open channel, with no sample line, no shelter, and minimal operator intervention. Three design choices make this possible.<\/p>\n<h3 id=\"1-double-junction-reference\"><span class=\"ez-toc-section\" id=\"1_Double-Junction_Reference\"><\/span>1. Double-Junction Reference<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>A single-junction reference cannot stand up to high-sulfate AMD water \u2014 the silver\/chloride junction becomes contaminated within days. The double-junction architecture interposes an intermediate electrolyte chamber, isolating the inner reference from the process. The result is a stable reference potential that holds calibration for weeks rather than days.<\/p>\n<h3 id=\"2-heavy-duty-glass-bulb-with-self-cleaning-geometry\"><span class=\"ez-toc-section\" id=\"2_Heavy-Duty_Glass_Bulb_with_Self-Cleaning_Geometry\"><\/span>2. Heavy-Duty Glass Bulb with Self-Cleaning Geometry<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>The pH-sensitive bulb is fabricated from a low-impedance glass formulated for service below pH 3. Its flat or hemispherical geometry is matched to flow direction, so the natural movement of water through the pipe sweeps particulates off the surface. In tougher service, an air-blast or ultrasonic cleaning option can be added.<\/p>\n<h3 id=\"3-robust-mechanical-body\"><span class=\"ez-toc-section\" id=\"3_Robust_Mechanical_Body\"><\/span>3. Robust Mechanical Body<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Mining service is also rough on the housing. The Shanghai ChiMay inline pH electrode uses a PEEK or PPS body with a 316L stainless or titanium mounting thread, NSF-listed wetted materials, and an IP68-rated cable gland. The probe can be installed in a high-vibration line near a centrifugal slurry pump without fatigue failures.<\/p>\n<h2 id=\"where-inline-ph-goes-in-an-amd-treatment-train\"><span class=\"ez-toc-section\" id=\"Where_Inline_pH_Goes_in_an_AMD_Treatment_Train\"><\/span>Where Inline pH Goes in an AMD Treatment Train<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>A typical lime-dosing neutralization system has three pH measurement points where the inline electrode shines.<\/p>\n<ul>\n<li><strong>Raw influent monitoring.<\/strong> Located upstream of the first dosing chamber, this point records the incoming pH and forms the feed signal for the dosing controller.<\/li>\n<li><strong>Reaction tank control.<\/strong> Installed inside or immediately downstream of the first reactor, this point closes the feedback loop on lime addition. Stability and response time at this location govern the consistency of the entire plant.<\/li>\n<li><strong>Discharge confirmation.<\/strong> A third probe at the final discharge confirms that the treated water has reached the regulatory pH window \u2014 typically 6 to 9 depending on the receiving water classification.<\/li>\n<\/ul>\n<p>Each location demands the same electrode technology but slightly different setup. The raw-influent probe sees the most aggressive water; the reaction-tank probe sees lime particulates and demands fast response; the discharge probe sees relatively clean water and is the easiest position to maintain.<\/p>\n<h2 id=\"calibration-strategy\"><span class=\"ez-toc-section\" id=\"Calibration_Strategy\"><\/span>Calibration Strategy<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>A common mistake is to calibrate inline AMD pH probes with the same monthly schedule used for benign service. Calibration intervals should be set by data, not by tradition. Shanghai ChiMay recommends:<\/p>\n<ul>\n<li>A two-point calibration at commissioning using pH 4 and pH 7 buffers<\/li>\n<li>Weekly verification with a grab sample analyzed on a <a href=\"\/tag\/benchtop-meter\" target=\"_blank\"><strong>benchtop meter<\/strong><\/a><\/li>\n<li>Recalibration when the verified offset exceeds 0.1 pH unit<\/li>\n<li>Electrode replacement when slope falls below 90 % of theoretical<\/li>\n<\/ul>\n<p>For most AMD installations, this means a calibration every two to four weeks and an electrode replacement every six to twelve months \u2014 far better than the one- to two-month replacement cycle typical of unsuitable probes.<\/p>\n<h2 id=\"integration-with-lime-dosing-control\"><span class=\"ez-toc-section\" id=\"Integration_with_Lime_Dosing_Control\"><\/span>Integration with Lime Dosing Control<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>The inline electrode is only as useful as the dosing controller behind it. Most modern systems use a PID or model-predictive controller that accepts the 4\u201320 mA signal from a Shanghai ChiMay pH transmitter and modulates a lime slurry pump or feeder. Two technical points matter at the integration boundary:<\/p>\n<ul>\n<li><strong>Damping.<\/strong> A small amount of signal damping (one to five seconds) smooths pump cycling without slowing the response.<\/li>\n<li><strong>Diagnostic data.<\/strong> Modern transmitters offer impedance and reference-potential diagnostics that warn of fouling before the measurement drifts out of tolerance. Feeding these diagnostics into the plant historian turns reactive maintenance into predictive maintenance.<\/li>\n<\/ul>\n<h2 id=\"operator-habits-that-make-or-break-the-installation\"><span class=\"ez-toc-section\" id=\"Operator_Habits_That_Make_or_Break_the_Installation\"><\/span>Operator Habits That Make or Break the Installation<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Technology alone is never enough. The mines that get long life out of an inline AMD pH electrode share a small set of habits:<\/p>\n<ul>\n<li>Clean the probe at every shift change with a soft brush and dilute hydrochloric acid rinse.<\/li>\n<li>Keep two pre-calibrated spare electrodes on the shelf so swap-out is a five-minute job.<\/li>\n<li>Treat any sudden drift greater than 0.3 pH unit as a signal that the probe needs attention, not that the buffer was bad.<\/li>\n<li>Log every calibration, every cleaning, and every replacement in the maintenance system so trends can be analyzed.<\/li>\n<\/ul>\n<h2 id=\"closing-thoughts\"><span class=\"ez-toc-section\" id=\"Closing_Thoughts\"><\/span>Closing Thoughts<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Acid mine drainage is not going away, and the cost of poor pH control \u2014 wasted reagent, exceedance fines, regulatory scrutiny \u2014 only grows as enforcement tightens. The good news is that the inline pH measurement technology required to control AMD reliably is mature, available, and surprisingly affordable when matched to the service. The Shanghai ChiMay inline pH electrode family was designed with these realities in mind: a double-junction reference, low-impedance glass, robust mechanical construction, and transmitter diagnostics that keep maintenance teams ahead of problems instead of behind them. Mines that adopt this technology consistently report lower reagent use, fewer compliance excursions, and far less time spent troubleshooting the most important measurement in the plant.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Inline pH Electrode Technology for Acid Mine Drainage Treatment: The Shanghai ChiMay Overview Acid mine drainage, or AMD, is one of the most stubborn water-quality problems in the global mining industry. It forms when sulfide minerals such as pyrite are exposed to oxygen and water, producing sulfuric acid and dissolved metals that can devastate downstream&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_kad_post_transparent":"","_kad_post_title":"","_kad_post_layout":"","_kad_post_sidebar_id":"","_kad_post_content_style":"","_kad_post_vertical_padding":"","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false},"categories":[1],"tags":[11145,134429,134481],"translation":{"provider":"WPGlobus","version":"2.12.0","language":"pt","enabled_languages":["en","zh","es","de","fr","ru","pt","ar","ja","ko","it","id","hi","th","vi","tr"],"languages":{"en":{"title":true,"content":true,"excerpt":false},"zh":{"title":false,"content":false,"excerpt":false},"es":{"title":false,"content":false,"excerpt":false},"de":{"title":false,"content":false,"excerpt":false},"fr":{"title":false,"content":false,"excerpt":false},"ru":{"title":false,"content":false,"excerpt":false},"pt":{"title":false,"content":false,"excerpt":false},"ar":{"title":false,"content":false,"excerpt":false},"ja":{"title":false,"content":false,"excerpt":false},"ko":{"title":false,"content":false,"excerpt":false},"it":{"title":false,"content":false,"excerpt":false},"id":{"title":false,"content":false,"excerpt":false},"hi":{"title":false,"content":false,"excerpt":false},"th":{"title":false,"content":false,"excerpt":false},"vi":{"title":false,"content":false,"excerpt":false},"tr":{"title":false,"content":false,"excerpt":false}}},"_links":{"self":[{"href":"https:\/\/shchimay.com\/pt\/wp-json\/wp\/v2\/posts\/31042"}],"collection":[{"href":"https:\/\/shchimay.com\/pt\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/shchimay.com\/pt\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/shchimay.com\/pt\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/shchimay.com\/pt\/wp-json\/wp\/v2\/comments?post=31042"}],"version-history":[{"count":0,"href":"https:\/\/shchimay.com\/pt\/wp-json\/wp\/v2\/posts\/31042\/revisions"}],"wp:attachment":[{"href":"https:\/\/shchimay.com\/pt\/wp-json\/wp\/v2\/media?parent=31042"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/shchimay.com\/pt\/wp-json\/wp\/v2\/categories?post=31042"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/shchimay.com\/pt\/wp-json\/wp\/v2\/tags?post=31042"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}