[{"data":1,"prerenderedAt":905},["ShallowReactive",2],{"site-footer-common":3,"glossary:thermal-substitution-rate":45,"glossary-related:thermal-substitution-rate":236},{"id":4,"extension":5,"footer":6,"meta":40,"navbar":41,"stem":43,"__hash__":44},"common\u002Fcommon.yml","yml",{"tagline":7,"links":8,"sections":9},"Acoustic cleaning intelligence for industrial fouling, soot, ash, dust and build-up.",[],[10,19,31],{"title":11,"links":12},"Product",[13,16],{"label":14,"to":15},"How it works","\u002F#product",{"label":17,"to":18},"Cost assessment","\u002F#hero",{"title":20,"links":21},"Company",[22,25,28],{"label":23,"to":24},"What we build","\u002F#about",{"label":26,"to":27},"Careers","\u002F#careers",{"label":29,"to":30},"Contact","\u002F#contact",{"title":32,"links":33},"Resources",[34,37],{"label":35,"to":36},"Blog","\u002Fresources\u002Fblog",{"label":38,"to":39},"Glossary","\u002Fglossary",{},{"links":42},[],"common","YocmZRy1AYfBbpgGVms-zhdiABlF8VTxHx6h4rDmZBA",{"id":46,"title":47,"aliases":48,"body":51,"category":215,"description":216,"extension":217,"meta":218,"navigation":219,"path":220,"relatedTerms":221,"seo":226,"sources":229,"stem":233,"term":234,"__hash__":235},"glossary\u002Fglossary\u002Fthermal-substitution-rate.md","Thermal substitution rate (TSR)",[49,50],"TSR","alternative-fuel substitution rate",{"type":52,"value":53,"toc":208},"minimark",[54,67,72,148,151,155,178,182],[55,56,57,60,61,66],"p",{},[58,59,47],"strong",{}," is the percentage of total kiln energy input supplied by ",[62,63,65],"a",{"href":64},"\u002Fglossary\u002Falternative-fuel","alternative fuels"," rather than fossil fuel (coal, petcoke, gas, oil). TSR is the headline AFR-adoption metric tracked by the cement industry and is central to every cement-major decarbonisation roadmap.",[68,69,71],"h2",{"id":70},"typical-tsr-ranges-by-region-2025","Typical TSR ranges by region (2025)",[73,74,75,88],"table",{},[76,77,78],"thead",{},[79,80,81,85],"tr",{},[82,83,84],"th",{},"Region",[82,86,87],{},"Average TSR",[89,90,91,100,108,116,124,132,140],"tbody",{},[79,92,93,97],{},[94,95,96],"td",{},"Northern Europe (DE, NL, AT)",[94,98,99],{},"60–80%",[79,101,102,105],{},[94,103,104],{},"Western Europe (FR, UK, IT, ES)",[94,106,107],{},"40–60%",[79,109,110,113],{},[94,111,112],{},"Southern Europe (GR, PT)",[94,114,115],{},"25–40%",[79,117,118,121],{},[94,119,120],{},"North America",[94,122,123],{},"15–25%",[79,125,126,129],{},[94,127,128],{},"China",[94,130,131],{},"5–10%",[79,133,134,137],{},[94,135,136],{},"India",[94,138,139],{},"10–20%",[79,141,142,145],{},[94,143,144],{},"Brazil \u002F LATAM",[94,146,147],{},"20–35%",[55,149,150],{},"Several European plants now exceed 90% TSR; the technical and procurement frontier sits beyond 95%.",[68,152,154],{"id":153},"why-higher-tsr-drives-sonic-horn-demand","Why higher TSR drives sonic-horn demand",[55,156,157,158,162,163,167,168,172,173,177],{},"Each step up in TSR raises the chlorine, sulphur and alkali loading reaching the ",[62,159,161],{"href":160},"\u002Fglossary\u002Fpreheater-tower","preheater tower"," — see ",[62,164,166],{"href":165},"\u002Fglossary\u002Fsulphur-cycle-chloride-cycle-alkali-cycle","sulphur and chloride cycles",". This intensifies coating, build-up and pluggage in the preheater, calciner and ",[62,169,171],{"href":170},"\u002Fglossary\u002Fkiln-inlet-riser-duct","kiln-inlet",", increasing the frequency and severity of cleaning interventions. ",[62,174,176],{"href":175},"\u002Fglossary\u002Fsonic-horn","Sonic horns"," become more valuable — and often more numerous — as TSR rises.",[68,179,181],{"id":180},"related-terms","Related terms",[183,184,185,191,197,202],"ul",{},[186,187,188],"li",{},[62,189,190],{"href":64},"Alternative fuel (AFR)",[186,192,193],{},[62,194,196],{"href":195},"\u002Fglossary\u002Frdf-srf-tdf","RDF \u002F SRF \u002F TDF",[186,198,199],{},[62,200,201],{"href":165},"Sulphur \u002F chloride \u002F alkali cycles",[186,203,204],{},[62,205,207],{"href":206},"\u002Fglossary\u002Fchloride-bypass","Chloride bypass",{"title":209,"searchDepth":210,"depth":210,"links":211},"",2,[212,213,214],{"id":70,"depth":210,"text":71},{"id":153,"depth":210,"text":154},{"id":180,"depth":210,"text":181},"cement","Thermal substitution rate (TSR) is the percentage of total kiln energy input supplied by alternative fuels rather than fossil fuel (coal, petcoke, gas, oil). TSR is the headline AFR-adoption metric tracked by the cement industry and is central to every cement-major decarbonisation roadmap.","md",{},true,"\u002Fglossary\u002Fthermal-substitution-rate",[222,223,224,225],"alternative-fuel","rdf-srf-tdf","sulphur-cycle-chloride-cycle-alkali-cycle","chloride-bypass",{"title":227,"description":228},"Thermal substitution rate (TSR) — alternative-fuel share of kiln energy","TSR is the percentage of total kiln-energy input supplied by alternative fuels rather than fossil fuel. The headline AFR adoption metric for cement-industry decarbonisation.",[230],{"title":231,"url":232},"Wikipedia — Cement kiln","https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FCement_kiln","glossary\u002Fthermal-substitution-rate","Thermal substitution rate","BMRoxkiM8uWOoZM6LLMqgRkvW2gkEoUcqAsOAS198bI",[237,423,583,801],{"id":238,"title":190,"aliases":239,"body":243,"category":215,"description":411,"extension":217,"meta":412,"navigation":219,"path":64,"relatedTerms":413,"seo":415,"sources":418,"stem":420,"term":421,"__hash__":422},"glossary\u002Fglossary\u002Falternative-fuel.md",[240,65,241,242],"AFR","secondary fuel","waste-derived fuel",{"type":52,"value":244,"toc":405},[245,262,266,301,305,330,334,337,371,380,382],[55,246,247,249,250,253,254,256,257,261],{},[58,248,190],{}," — sometimes ",[251,252,241],"em",{}," or ",[251,255,242],{}," — refers to non-fossil energy sources used to replace coal, petcoke and natural gas in cement-kiln combustion. The cement industry is the largest single user of AFR worldwide because the high temperatures and long residence times in a ",[62,258,260],{"href":259},"\u002Fglossary\u002Frotary-kiln","rotary kiln"," destroy organic contaminants, and the alkaline raw materials neutralise acidic combustion products.",[68,263,265],{"id":264},"common-afr-streams","Common AFR streams",[183,267,268,274,280,286,289,292,295,298],{},[186,269,270,273],{},[62,271,272],{"href":195},"RDF"," — refuse-derived fuel",[186,275,276,279],{},[62,277,278],{"href":195},"SRF"," — solid recovered fuel (higher-spec RDF)",[186,281,282,285],{},[62,283,284],{"href":195},"TDF"," — tyre-derived fuel",[186,287,288],{},"Sewage sludge (dried)",[186,290,291],{},"Animal-meal residues",[186,293,294],{},"Agricultural residues",[186,296,297],{},"Used solvents and waste oils",[186,299,300],{},"Plastic and paper fractions",[68,302,304],{"id":303},"drivers","Drivers",[183,306,307,313,319,325],{},[186,308,309,312],{},[58,310,311],{},"CO₂ reduction"," — biomass fractions reduce net carbon emissions",[186,314,315,318],{},[58,316,317],{},"Waste-disposal economics"," — gate fees offset fuel cost",[186,320,321,324],{},[58,322,323],{},"EU ETS pressure"," — carbon prices punish fossil-fuel firing",[186,326,327],{},[58,328,329],{},"Regional waste-management policies",[68,331,333],{"id":332},"operational-consequences","Operational consequences",[55,335,336],{},"AFR firing typically intensifies several existing operational problems:",[183,338,339,344,356,363],{},[186,340,341,342],{},"More chlorine and sulphur in the ",[62,343,166],{"href":165},[186,345,346,347,351,352],{},"More ",[62,348,350],{"href":349},"\u002Fglossary\u002Fkiln-inlet-ring-snowman","kiln-inlet build-up"," and ",[62,353,355],{"href":354},"\u002Fglossary\u002Fbuild-up-coating-accretion","preheater coatings",[186,357,358,359,362],{},"More frequent ",[62,360,361],{"href":206},"chloride bypass"," operation",[186,364,365,366,370],{},"More demanding ",[62,367,369],{"href":368},"\u002Fglossary\u002Fcalciner","calciner"," burner control",[55,372,373,351,375,379],{},[62,374,176],{"href":175},[62,376,378],{"href":377},"\u002Fglossary\u002Fair-cannon-air-blaster","air cannons"," on the preheater and kiln inlet become more important as TSR rises.",[68,381,181],{"id":180},[183,383,384,388,392,397,401],{},[186,385,386],{},[62,387,196],{"href":195},[186,389,390],{},[62,391,47],{"href":220},[186,393,394],{},[62,395,396],{"href":368},"Calciner",[186,398,399],{},[62,400,207],{"href":206},[186,402,403],{},[62,404,201],{"href":165},{"title":209,"searchDepth":210,"depth":210,"links":406},[407,408,409,410],{"id":264,"depth":210,"text":265},{"id":303,"depth":210,"text":304},{"id":332,"depth":210,"text":333},{"id":180,"depth":210,"text":181},"Alternative fuel (AFR) — sometimes secondary fuel or waste-derived fuel — refers to non-fossil energy sources used to replace coal, petcoke and natural gas in cement-kiln combustion. The cement industry is the largest single user of AFR worldwide because the high temperatures and long residence times in a rotary kiln destroy organic contaminants, and the alkaline raw materials neutralise acidic combustion products.",{},[223,414,369,225,224],"thermal-substitution-rate",{"title":416,"description":417},"Alternative fuel (AFR) — non-fossil fuels for cement kilns","Alternative fuels (AFR) replace fossil fuel in cement kilns. They cut CO2 emissions and waste-disposal cost but increase chlorine, sulphur and alkali loading in the kiln gas.",[419],{"title":231,"url":232},"glossary\u002Falternative-fuel","Alternative fuel","8a9Wktj3h9L0w-C7tMXKI-y1T31K4IsFiIBPj8b461Y",{"id":424,"title":196,"aliases":425,"body":429,"category":215,"description":570,"extension":217,"meta":571,"navigation":219,"path":195,"relatedTerms":572,"seo":573,"sources":576,"stem":580,"term":581,"__hash__":582},"glossary\u002Fglossary\u002Frdf-srf-tdf.md",[426,427,428,272,278,284],"refuse-derived fuel","solid recovered fuel","tyre-derived fuel",{"type":52,"value":430,"toc":565},[431,449,517,521,538,542,548,550],[55,432,433,435,436,351,438,440,441,443,444,448],{},[58,434,272],{},", ",[58,437,278],{},[58,439,284],{}," are the three dominant waste-derived ",[62,442,65],{"href":64}," used in cement kilns, ",[62,445,447],{"href":446},"\u002Fglossary\u002Fwaste-to-energy","waste-to-energy"," plants and industrial boilers.",[73,450,451,467],{},[76,452,453],{},[79,454,455,458,461,464],{},[82,456,457],{},"Fuel",[82,459,460],{},"Source",[82,462,463],{},"Specification",[82,465,466],{},"Calorific value",[89,468,469,485,501],{},[79,470,471,476,479,482],{},[94,472,473,475],{},[58,474,272],{}," (Refuse-Derived Fuel)",[94,477,478],{},"Municipal solid waste, lightly processed",[94,480,481],{},"Loose, no formal CEN\u002FTS specification",[94,483,484],{},"12–18 MJ\u002Fkg",[79,486,487,492,495,498],{},[94,488,489,491],{},[58,490,278],{}," (Solid Recovered Fuel)",[94,493,494],{},"MSW + commercial waste, processed to CEN\u002FTS 15359 spec",[94,496,497],{},"Defined particle size, ash content, calorific value, Cl, Hg",[94,499,500],{},"15–20 MJ\u002Fkg",[79,502,503,508,511,514],{},[94,504,505,507],{},[58,506,284],{}," (Tyre-Derived Fuel)",[94,509,510],{},"End-of-life tyres, shredded",[94,512,513],{},"Shred-size grade or whole-tyre",[94,515,516],{},"28–35 MJ\u002Fkg",[68,518,520],{"id":519},"trade-offs","Trade-offs",[183,522,523,528,533],{},[186,524,525,527],{},[58,526,272],{},": cheap, high availability, variable composition; high chlorine swings",[186,529,530,532],{},[58,531,278],{},": more consistent and predictable than RDF; commands premium gate fees",[186,534,535,537],{},[58,536,284],{},": very high calorific value, supplies iron and sulphur to clinker chemistry; rubber-handling logistics",[68,539,541],{"id":540},"fouling-implications","Fouling implications",[55,543,544,545,547],{},"All three add chlorine, sulphur and alkali metals beyond what fossil coal contributes. The chloride loading from chlorinated plastics in RDF \u002F SRF is the dominant driver of ",[62,546,225],{"href":206}," sizing. TDF adds zinc and iron oxides that can affect clinker chemistry.",[68,549,181],{"id":180},[183,551,552,556,560],{},[186,553,554],{},[62,555,190],{"href":64},[186,557,558],{},[62,559,47],{"href":220},[186,561,562],{},[62,563,564],{"href":446},"Waste-to-energy",{"title":209,"searchDepth":210,"depth":210,"links":566},[567,568,569],{"id":519,"depth":210,"text":520},{"id":540,"depth":210,"text":541},{"id":180,"depth":210,"text":181},"RDF, SRF and TDF are the three dominant waste-derived alternative fuels used in cement kilns, waste-to-energy plants and industrial boilers.",{},[222,414,447],{"title":574,"description":575},"RDF, SRF and TDF — the three main waste-derived alternative fuels","RDF (refuse-derived fuel), SRF (solid recovered fuel, higher spec) and TDF (tyre-derived fuel) are the three dominant waste-derived alternative fuels for cement kilns and WtE boilers.",[577],{"title":578,"url":579},"Wikipedia — Refuse-derived fuel","https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FRefuse-derived_fuel","glossary\u002Frdf-srf-tdf","RDF, SRF and TDF","RoQpf87g_jG3WY3RTYBUUo8tH9DaZr_5iiSblH89SVk",{"id":584,"title":201,"aliases":585,"body":590,"category":215,"description":786,"extension":217,"meta":787,"navigation":219,"path":165,"relatedTerms":788,"seo":791,"sources":794,"stem":798,"term":799,"__hash__":800},"glossary\u002Fglossary\u002Fsulphur-cycle-chloride-cycle-alkali-cycle.md",[586,587,588,589],"sulphur cycle","chloride cycle","alkali cycle","volatile cycles",{"type":52,"value":591,"toc":780},[592,613,617,688,692,701,704,724,728,758,760],[55,593,594,595,435,598,351,601,604,605,608,609,612],{},"The ",[58,596,597],{},"sulphur",[58,599,600],{},"chloride",[58,602,603],{},"alkali cycles"," describe how volatile species evaporate from the ",[62,606,607],{"href":259},"rotary-kiln"," burning zone, rise with the gas flow, condense in the cooler ",[62,610,611],{"href":160},"preheater"," above, return to the kiln in the descending raw meal, and recirculate. Each cycle has its own behaviour and operational consequences.",[68,614,616],{"id":615},"the-three-cycles","The three cycles",[73,618,619,635],{},[76,620,621],{},[79,622,623,626,629,632],{},[82,624,625],{},"Cycle",[82,627,628],{},"Volatile species",[82,630,631],{},"Condensation window",[82,633,634],{},"Operational consequence",[89,636,637,653,672],{},[79,638,639,644,647,650],{},[94,640,641],{},[58,642,643],{},"Sulphur cycle",[94,645,646],{},"SO₂, SO₃, alkali sulphates",[94,648,649],{},"800–1,000 °C",[94,651,652],{},"Sticky alkali-sulphate coatings in preheater stages 4–5",[79,654,655,660,663,666],{},[94,656,657],{},[58,658,659],{},"Chloride cycle",[94,661,662],{},"KCl, NaCl",[94,664,665],{},"700–900 °C",[94,667,668,669],{},"Aggressive sticky coatings; primary driver of ",[62,670,671],{"href":349},"kiln-inlet snowmen",[79,673,674,679,682,685],{},[94,675,676],{},[58,677,678],{},"Alkali cycle",[94,680,681],{},"K₂O, Na₂O",[94,683,684],{},"wide",[94,686,687],{},"Sets cement chemistry; affects strength development",[68,689,691],{"id":690},"why-the-cycles-matter-operationally","Why the cycles matter operationally",[55,693,694,695,697,698,700],{},"All three cycles concentrate volatiles in the gas-phase recirculation loop unless something extracts them. Conventional cement raw materials and fossil fuels carry modest loadings; ",[62,696,65],{"href":64}," — especially ",[62,699,581],{"href":195}," — add substantially more chlorine, sulphur and sometimes alkali.",[55,702,703],{},"When a cycle saturates:",[183,705,706,714,719],{},[186,707,708,710,711,713],{},[58,709,659],{}," — heavy ",[62,712,350],{"href":349},"; kiln stop unavoidable",[186,715,716,718],{},[58,717,643],{}," — preheater coatings; cyclone pluggage",[186,720,721,723],{},[58,722,678],{}," — clinker quality issues; cement performance drift",[68,725,727],{"id":726},"cycle-management","Cycle management",[183,729,730,737,743,749],{},[186,731,732,736],{},[58,733,734],{},[62,735,207],{"href":206}," — extracts a slipstream of gas from the kiln inlet to remove chlorine",[186,738,739,742],{},[58,740,741],{},"Raw-material substitution"," — selecting lower-Cl\u002F-S\u002F-alkali raw materials",[186,744,745,748],{},[58,746,747],{},"Fuel blending"," — controlling AFR chlorine and sulphur content",[186,750,751,757],{},[58,752,753,351,755],{},[62,754,176],{"href":175},[62,756,378],{"href":377}," on the preheater and kiln inlet to keep accumulating coatings under control",[68,759,181],{"id":180},[183,761,762,767,772,776],{},[186,763,764],{},[62,765,766],{"href":160},"Preheater tower",[186,768,769],{},[62,770,771],{"href":349},"Kiln-inlet ring \u002F snowman",[186,773,774],{},[62,775,421],{"href":64},[186,777,778],{},[62,779,207],{"href":206},{"title":209,"searchDepth":210,"depth":210,"links":781},[782,783,784,785],{"id":615,"depth":210,"text":616},{"id":690,"depth":210,"text":691},{"id":726,"depth":210,"text":727},{"id":180,"depth":210,"text":181},"The sulphur, chloride and alkali cycles describe how volatile species evaporate from the rotary-kiln burning zone, rise with the gas flow, condense in the cooler preheater above, return to the kiln in the descending raw meal, and recirculate. Each cycle has its own behaviour and operational consequences.",{},[789,790,222,225],"preheater-tower","kiln-inlet-ring-snowman",{"title":792,"description":793},"Sulphur, chloride and alkali cycles — recirculating volatiles in cement kilns","Sulphur, chloride and alkali cycles describe how volatile species evaporate from the kiln burning zone, condense in the cooler preheater, and recirculate. Their build-up drives kiln-stop fouling.",[795],{"title":796,"url":797},"ECRA — Sulphur and Chloride Cycles","https:\u002F\u002Fwww.ecra-online.org\u002Fnewsletters\u002Fsulphur-and-chloride-cycles-and-the-use-of-alternative-fuels-or-raw-materials","glossary\u002Fsulphur-cycle-chloride-cycle-alkali-cycle","Sulphur, chloride and alkali cycles","1q8xkjwUqGJNxldxfJ12G0VfAG8TsdalMouPDL7DUl8",{"id":802,"title":207,"aliases":803,"body":807,"category":215,"description":891,"extension":217,"meta":892,"navigation":219,"path":206,"relatedTerms":893,"seo":896,"sources":899,"stem":903,"term":207,"__hash__":904},"glossary\u002Fglossary\u002Fchloride-bypass.md",[804,805,806],"cement chloride bypass","bypass system (cement)","Cl bypass",{"type":52,"value":808,"toc":886},[809,821,825,837,841,844,855,860,862],[55,810,811,812,814,815,817,818,820],{},"A ",[58,813,361],{}," is a flue-gas slipstream system that extracts a fraction (typically 3–15%) of the kiln gas before it enters the ",[62,816,161],{"href":160},", cooling it and removing the chlorine-rich dust to prevent chlorine accumulation in the ",[62,819,587],{"href":165},".",[68,822,824],{"id":823},"why-bypasses-are-increasingly-needed","Why bypasses are increasingly needed",[55,826,827,828,697,831,833,834,836],{},"Conventional cement raw materials and fossil fuels carry modest chlorine and sulphur. ",[62,829,830],{"href":64},"Alternative fuels",[62,832,581],{"href":195}," and sewage sludge — carry much more. Above a TSR threshold (typically 30–50% depending on raw materials), the chloride cycle saturates and starts to drive heavy ",[62,835,350],{"href":349}," that ultimately causes kiln stops. The bypass extracts chlorine fast enough to stabilise the cycle and let the plant operate at high TSR.",[68,838,840],{"id":839},"bypass-specific-fouling","Bypass-specific fouling",[55,842,843],{},"The bypass duct itself, the quenching tower, and the bypass dust hopper all foul aggressively:",[183,845,846,849,852],{},[186,847,848],{},"Hot kiln gas containing high concentrations of chlorides condenses on the cooler bypass-duct walls",[186,850,851],{},"Quench water dropout creates sticky chloride-rich slurry",[186,853,854],{},"Bypass dust hopper bridges with fine sticky chloride material",[55,856,857,859],{},[62,858,176],{"href":175}," on the bypass duct and dust hopper are the standard cleaning fit.",[68,861,181],{"id":180},[183,863,864,869,873,877,881],{},[186,865,866],{},[62,867,868],{"href":170},"Kiln inlet \u002F riser duct",[186,870,871],{},[62,872,201],{"href":165},[186,874,875],{},[62,876,421],{"href":64},[186,878,879],{},[62,880,766],{"href":160},[186,882,883],{},[62,884,885],{"href":175},"Sonic horn",{"title":209,"searchDepth":210,"depth":210,"links":887},[888,889,890],{"id":823,"depth":210,"text":824},{"id":839,"depth":210,"text":840},{"id":180,"depth":210,"text":181},"A chloride bypass is a flue-gas slipstream system that extracts a fraction (typically 3–15%) of the kiln gas before it enters the preheater tower, cooling it and removing the chlorine-rich dust to prevent chlorine accumulation in the chloride cycle.",{},[894,224,222,789,895],"kiln-inlet-riser-duct","sonic-horn",{"title":897,"description":898},"Chloride bypass — extracting a kiln-gas slipstream to control Cl cycles","A chloride bypass extracts a slipstream of kiln gas before the preheater to remove chlorine from the recirculating Cl cycle. Essential at high TSR; the bypass duct itself fouls heavily.",[900],{"title":901,"url":902},"VDZ — Bypass Systems","https:\u002F\u002Fwww.scribd.com\u002Fdocument\u002F499939627\u002FVDZ-3-5-en-Bypass-Systems","glossary\u002Fchloride-bypass","igkOavGw_l8HvBNezdUpZrruMof8Bd1RlhJPxqRLeVE",1782613729195]