[{"data":1,"prerenderedAt":1063},["ShallowReactive",2],{"site-footer-common":3,"glossary:ammonium-bisulphate":45,"glossary-related:ammonium-bisulphate":233},{"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":53,"category":211,"description":212,"extension":213,"meta":214,"navigation":215,"path":216,"relatedTerms":217,"seo":223,"sources":226,"stem":230,"term":231,"__hash__":232},"glossary\u002Fglossary\u002Fammonium-bisulphate.md","Ammonium bisulphate (ABS)",[49,50,51,52],"ABS","ammonium bisulfate","ammonium sulphate","NH4HSO4",{"type":54,"value":55,"toc":204},"minimark",[56,84,89,92,130,134,173,177],[57,58,59,63,64,67,68,73,74,78,79,83],"p",{},[60,61,62],"strong",{},"Ammonium bisulphate (NH₄HSO₄, ABS)"," — sometimes written ",[65,66,50],"em",{}," in US technical literature — is a sticky, low-melting deposit formed when ",[69,70,72],"a",{"href":71},"\u002Fglossary\u002Fammonia-slip","slipped ammonia"," reacts with SO₃ in cooling flue gas. ABS condenses between roughly 150 °C and 250 °C, coating the cold end of any ",[69,75,77],{"href":76},"\u002Fglossary\u002Fair-heater","air heater"," downstream of an ",[69,80,82],{"href":81},"\u002Fglossary\u002Fselective-catalytic-reduction","SCR",".",[85,86,88],"h2",{"id":87},"why-abs-is-the-most-feared-cold-end-deposit","Why ABS is the most-feared cold-end deposit",[57,90,91],{},"ABS is uniquely problematic because it is:",[93,94,95,102,112,118,124],"ul",{},[96,97,98,101],"li",{},[60,99,100],{},"Sticky"," — bonds tenaciously to air-heater baskets and economiser tubes",[96,103,104,107,108],{},[60,105,106],{},"Hygroscopic"," — picks up moisture and accelerates ",[69,109,111],{"href":110},"\u002Fglossary\u002Fcold-end-corrosion-dew-point-corrosion","cold-end corrosion",[96,113,114,117],{},[60,115,116],{},"Hard to remove"," — resists steam sootblowing once consolidated",[96,119,120,123],{},[60,121,122],{},"Self-reinforcing"," — coated surfaces trap more ash, accelerating fouling",[96,125,126,129],{},[60,127,128],{},"Concentrated in a narrow temperature band"," — predictably plugs the same air-heater rows",[85,131,133],{"id":132},"mitigation","Mitigation",[93,135,136,145,151,157,167],{},[96,137,138,144],{},[60,139,140,141],{},"Minimise ",[69,142,143],{"href":71},"ammonia slip"," at the SCR (the single biggest lever)",[96,146,147,150],{},[60,148,149],{},"Manage SO₃ formation"," — fuel sulphur control, catalyst formulation",[96,152,153,156],{},[60,154,155],{},"Avoid the dew-point window"," — keep cold-end gas temperature above the formation band",[96,158,159,166],{},[60,160,161,165],{},[69,162,164],{"href":163},"\u002Fglossary\u002Fsonic-horn","Sonic horns"," on the cold end"," — continuous cleaning prevents ABS from consolidating before periodic water-washing",[96,168,169,172],{},[60,170,171],{},"Water-washing campaigns"," — periodic offline washes restore air-heater performance",[85,174,176],{"id":175},"related-terms","Related terms",[93,178,179,184,189,194,199],{},[96,180,181],{},[69,182,183],{"href":71},"Ammonia slip",[96,185,186],{},[69,187,188],{"href":81},"Selective Catalytic Reduction (SCR)",[96,190,191],{},[69,192,193],{"href":76},"Air heater",[96,195,196],{},[69,197,198],{"href":110},"Cold-end corrosion \u002F dew-point corrosion",[96,200,201],{},[69,202,203],{"href":163},"Sonic horn",{"title":205,"searchDepth":206,"depth":206,"links":207},"",2,[208,209,210],{"id":87,"depth":206,"text":88},{"id":132,"depth":206,"text":133},{"id":175,"depth":206,"text":176},"scr-sncr","Ammonium bisulphate (NH₄HSO₄, ABS) — sometimes written ammonium bisulfate in US technical literature — is a sticky, low-melting deposit formed when slipped ammonia reacts with SO₃ in cooling flue gas. ABS condenses between roughly 150 °C and 250 °C, coating the cold end of any air heater downstream of an SCR.","md",{},true,"\u002Fglossary\u002Fammonium-bisulphate",[218,219,220,221,222],"ammonia-slip","selective-catalytic-reduction","air-heater","cold-end-corrosion-dew-point-corrosion","sonic-horn",{"title":224,"description":225},"Ammonium bisulphate (ABS) — sticky deposit from SCR slip plus SO3","Ammonium bisulphate is a sticky low-melting deposit formed when slipped ammonia reacts with SO3 in cooling flue gas. The dominant cold-end fouling species on SCR-equipped boilers.",[227],{"title":228,"url":229},"POWER Magazine — SO3's impacts on plant O&M","https:\u002F\u002Fwww.powermag.com\u002Fso3s-impacts-on-plant-om-part-ii\u002F","glossary\u002Fammonium-bisulphate","Ammonium bisulphate","eVfkw0arMYLXvUn7Eb2ZquRKgct13PXCySe8Iclt3GY",[234,381,533,714,833],{"id":235,"title":183,"aliases":236,"body":239,"category":211,"description":365,"extension":213,"meta":366,"navigation":215,"path":71,"relatedTerms":367,"seo":372,"sources":375,"stem":379,"term":183,"__hash__":380},"glossary\u002Fglossary\u002Fammonia-slip.md",[237,238],"NH3 slip","ammonia breakthrough",{"type":54,"value":240,"toc":359},[241,254,258,300,304,320,324,333,335],[57,242,243,245,246,248,249,253],{},[60,244,183],{}," is the concentration of unreacted ammonia (NH₃) in the flue gas leaving an ",[69,247,82],{"href":81}," or ",[69,250,252],{"href":251},"\u002Fglossary\u002Fselective-non-catalytic-reduction","SNCR"," system. It is the single most important operational KPI after NOx reduction itself: slip is regulated (typically capped at 2–10 ppm in permits), represents wasted reagent, and drives downstream fouling.",[85,255,257],{"id":256},"causes-of-high-ammonia-slip","Causes of high ammonia slip",[93,259,260,270,283,289,294],{},[96,261,262,265,266],{},[60,263,264],{},"Poor NH₃\u002FNOx mixing"," at the ",[69,267,269],{"href":268},"\u002Fglossary\u002Fammonia-injection-grid","AIG",[96,271,272,248,278,282],{},[60,273,274],{},[69,275,277],{"href":276},"\u002Fglossary\u002Fcatalyst-masking","Catalyst masking",[69,279,281],{"href":280},"\u002Fglossary\u002Fcatalyst-pluggage","pluggage"," reducing active surface area",[96,284,285,288],{},[60,286,287],{},"Catalyst age and de-activation"," towards end of life",[96,290,291],{},[60,292,293],{},"Operating temperature outside the catalyst window",[96,295,296,299],{},[60,297,298],{},"Over-injection of ammonia"," to compensate for falling NOx-reduction efficiency",[85,301,303],{"id":302},"downstream-consequences","Downstream consequences",[57,305,306,307,310,311,314,315,319],{},"Slipped ammonia combines with SO₃ in cooling flue gas to form ",[69,308,309],{"href":216},"ammonium bisulphate (ABS)",", a sticky low-melting deposit that fouls ",[69,312,313],{"href":76},"air heaters",", ",[69,316,318],{"href":317},"\u002Fglossary\u002Feconomiser","economisers"," and downstream catalysts and filters. Excessive slip can therefore destroy the cold end of a boiler within months.",[85,321,323],{"id":322},"sonic-horns-and-slip-reduction","Sonic horns and slip reduction",[57,325,326,328,329,332],{},[69,327,164],{"href":163}," reduce slip indirectly by keeping the catalyst face clear of ",[69,330,331],{"href":276},"masking"," deposits, which preserves active surface area, which lets the catalyst convert ammonia to nitrogen instead of letting it slip. They also keep the AIG decks clean, preserving the designed spray pattern.",[85,334,176],{"id":175},[93,336,337,341,346,351,355],{},[96,338,339],{},[69,340,188],{"href":81},[96,342,343],{},[69,344,345],{"href":251},"Selective Non-Catalytic Reduction (SNCR)",[96,347,348],{},[69,349,350],{"href":268},"Ammonia injection grid",[96,352,353],{},[69,354,231],{"href":216},[96,356,357],{},[69,358,277],{"href":276},{"title":205,"searchDepth":206,"depth":206,"links":360},[361,362,363,364],{"id":256,"depth":206,"text":257},{"id":302,"depth":206,"text":303},{"id":322,"depth":206,"text":323},{"id":175,"depth":206,"text":176},"Ammonia slip is the concentration of unreacted ammonia (NH₃) in the flue gas leaving an SCR or SNCR system. It is the single most important operational KPI after NOx reduction itself: slip is regulated (typically capped at 2–10 ppm in permits), represents wasted reagent, and drives downstream fouling.",{},[219,368,369,370,371],"selective-non-catalytic-reduction","ammonia-injection-grid","ammonium-bisulphate","catalyst-masking",{"title":373,"description":374},"Ammonia slip — unreacted NH3 leaving an SCR or SNCR system","Ammonia slip is unreacted ammonia leaving the DeNOx system in the flue gas. It is regulated, expensive in lost reagent, and causes ammonium-bisulphate fouling downstream.",[376],{"title":377,"url":378},"Power Engineering — Selective Catalytic Reduction: Operational Issues","https:\u002F\u002Fwww.power-eng.com\u002Fenvironmental-emissions\u002Fselective-catalytic-reduction-operational-issues-and-guidelines\u002F","glossary\u002Fammonia-slip","BU6p3qY3enI-T7Yz_rpYjEbWD0YUtLcL2fA38Y4iZN0",{"id":382,"title":188,"aliases":383,"body":386,"category":211,"description":514,"extension":213,"meta":515,"navigation":215,"path":81,"relatedTerms":516,"seo":520,"sources":523,"stem":530,"term":531,"__hash__":532},"glossary\u002Fglossary\u002Fselective-catalytic-reduction.md",[82,384,385],"SCR system","SCR reactor",{"type":54,"value":387,"toc":509},[388,407,411,426,430,433,460,474,476],[57,389,390,392,393,397,398,402,403,406],{},[60,391,188],{}," is the dominant flue-gas NOx-control technology on coal-fired and gas-fired utility boilers, ",[69,394,396],{"href":395},"\u002Fglossary\u002Fheat-recovery-steam-generator","HRSGs"," in combined-cycle plants, ",[69,399,401],{"href":400},"\u002Fglossary\u002Fwaste-to-energy","waste-to-energy"," and ",[69,404,405],{"href":400},"biomass"," boilers, cement plants and major refining furnaces. Ammonia or aqueous urea is injected upstream of a catalyst bed; the catalyst lowers the activation energy for the reaction NOx + NH₃ → N₂ + H₂O, achieving 80–95% NOx reduction across the reactor.",[85,408,410],{"id":409},"reactor-layout","Reactor layout",[57,412,413,414,417,418,421,422,425],{},"A typical SCR reactor is a vertical or horizontal duct containing 2–4 layers of catalyst modules. Upstream of the catalyst sits the ",[69,415,416],{"href":268},"ammonia injection grid (AIG)"," that distributes the ammonia evenly into the flue gas. Most installations operate in the ",[60,419,420],{},"high-dust"," position (between economiser and air heater) where catalyst temperature is around 300–400 °C; ",[60,423,424],{},"tail-end"," SCRs sit downstream of particulate control at lower temperatures, with the trade-off of needing flue-gas reheating.",[85,427,429],{"id":428},"fouling-and-cleaning","Fouling and cleaning",[57,431,432],{},"SCR catalysts foul in two ways:",[93,434,435,452],{},[96,436,437,442,443,402,447,451],{},[60,438,439],{},[69,440,441],{"href":280},"Pluggage"," — fly ash, ",[69,444,446],{"href":445},"\u002Fglossary\u002Fpopcorn-ash","popcorn ash",[69,448,450],{"href":449},"\u002Fglossary\u002Flarge-particle-ash","large-particle ash"," wedge into the catalyst cells, blocking the gas path",[96,453,454,459],{},[60,455,456],{},[69,457,458],{"href":276},"Masking"," — a thin layer of deposit covers the active sites; gas flow continues but catalytic activity falls",[57,461,462,463,465,466,314,470,473],{},"Both reduce NOx-reduction efficiency, raise ",[69,464,143],{"href":71},", and shorten catalyst life. Cleaning options include steam ",[69,467,469],{"href":468},"\u002Fglossary\u002Fsteam-sootblower","sootblowers",[69,471,472],{"href":163},"sonic horns"," and offline campaigns (vacuum \u002F water wash \u002F regeneration). Sonic horns are increasingly favoured because they continuously dislodge ash before it cements onto the catalyst face, without the steam erosion of mechanical sootblowing.",[85,475,176],{"id":175},[93,477,478,482,486,490,494,499,505],{},[96,479,480],{},[69,481,345],{"href":251},[96,483,484],{},[69,485,350],{"href":268},[96,487,488],{},[69,489,183],{"href":71},[96,491,492],{},[69,493,277],{"href":276},[96,495,496],{},[69,497,498],{"href":280},"Catalyst pluggage",[96,500,501],{},[69,502,504],{"href":503},"\u002Fglossary\u002Fhoneycomb-catalyst","Honeycomb catalyst",[96,506,507],{},[69,508,203],{"href":163},{"title":205,"searchDepth":206,"depth":206,"links":510},[511,512,513],{"id":409,"depth":206,"text":410},{"id":428,"depth":206,"text":429},{"id":175,"depth":206,"text":176},"Selective Catalytic Reduction (SCR) is the dominant flue-gas NOx-control technology on coal-fired and gas-fired utility boilers, HRSGs in combined-cycle plants, waste-to-energy and biomass boilers, cement plants and major refining furnaces. Ammonia or aqueous urea is injected upstream of a catalyst bed; the catalyst lowers the activation energy for the reaction NOx + NH₃ → N₂ + H₂O, achieving 80–95% NOx reduction across the reactor.",{},[368,517,369,218,371,518,519,222],"denox","catalyst-pluggage","honeycomb-catalyst",{"title":521,"description":522},"Selective Catalytic Reduction (SCR) — how the dominant NOx-control technology works","SCR is the dominant NOx-control technology on industrial combustion plant. Ammonia is injected upstream of a catalyst that converts NOx to nitrogen and water.",[524,527],{"title":525,"url":526},"Wikipedia — Selective catalytic reduction","https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FSelective_catalytic_reduction",{"title":528,"url":529},"Power Engineering — SCR Catalyst Cleaning: Sootblowers vs. Acoustic Horns","https:\u002F\u002Fwww.power-eng.com\u002Foperations-maintenance\u002Fscr-catalyst-cleaningsootblowers-vs-acoustic-horns\u002F","glossary\u002Fselective-catalytic-reduction","Selective Catalytic Reduction","fmMCMd4NY3eZdSk_UYlbZ9ryi-9CR2Os6DivQjXEPCU",{"id":534,"title":535,"aliases":536,"body":539,"category":699,"description":700,"extension":213,"meta":701,"navigation":215,"path":76,"relatedTerms":702,"seo":705,"sources":708,"stem":712,"term":193,"__hash__":713},"glossary\u002Fglossary\u002Fair-heater.md","Air heater (APH)",[537,538,313],"air preheater","APH",{"type":54,"value":540,"toc":693},[541,555,559,609,613,626,651,655,661,663],[57,542,543,544,546,547,549,550,554],{},"An ",[60,545,77],{}," — also called an ",[60,548,537],{}," (APH) — is the final heat-recovery device in a boiler's ",[69,551,553],{"href":552},"\u002Fglossary\u002Fconvective-pass-backpass","convective pass",", recovering low-grade heat from cooling flue gas to preheat the combustion air. APHs lift overall boiler efficiency by 5–10 percentage points and are critical to heat-rate performance.",[85,556,558],{"id":557},"aph-types","APH types",[560,561,562,575],"table",{},[563,564,565],"thead",{},[566,567,568,572],"tr",{},[569,570,571],"th",{},"Type",[569,573,574],{},"Description",[576,577,578,590,601],"tbody",{},[566,579,580,587],{},[581,582,583],"td",{},[69,584,586],{"href":585},"\u002Fglossary\u002Fljungstrom-air-preheater","Ljungström \u002F regenerative",[581,588,589],{},"Rotating matrix of heat-exchange baskets cycling between gas and air sides",[566,591,592,598],{},[581,593,594],{},[69,595,597],{"href":596},"\u002Fglossary\u002Ftubular-air-preheater","Tubular",[581,599,600],{},"Fixed tube bundle with flue gas through tubes, air around them",[566,602,603,606],{},[581,604,605],{},"Plate-type",[581,607,608],{},"Cross-flow plate exchanger; smaller industrial duty",[85,610,612],{"id":611},"the-cold-end-problem","The cold-end problem",[57,614,615,616,620,621,625],{},"The APH cold end is the coolest point in the flue-gas path before the ",[69,617,619],{"href":618},"\u002Fglossary\u002Felectrostatic-precipitator","ESP"," \u002F ",[69,622,624],{"href":623},"\u002Fglossary\u002Fbaghouse","baghouse",". Two related failure modes dominate:",[93,627,628,638],{},[96,629,630,634,635,637],{},[60,631,632],{},[69,633,47],{"href":216}," fouling on boilers with upstream ",[69,636,82],{"href":81},": sticky deposits plug Ljungström baskets and tubular APH tubes",[96,639,640,645,646,650],{},[60,641,642],{},[69,643,644],{"href":110},"Cold-end corrosion"," below the ",[69,647,649],{"href":648},"\u002Fglossary\u002Facid-dew-point","acid dew point"," — sulphuric acid condenses and attacks baskets and tubes",[85,652,654],{"id":653},"why-sonic-horns-are-routinely-specified-on-aphs","Why sonic horns are routinely specified on APHs",[57,656,657,658,660],{},"ABS fouling is the single most common reason plants install ",[69,659,472],{"href":163}," on the cold end. Continuous low-amplitude vibration prevents ABS from consolidating between water-wash campaigns, extending the campaign interval from quarterly to annual and avoiding capacity-derate excursions.",[85,662,176],{"id":175},[93,664,665,671,676,681,685,689],{},[96,666,667],{},[69,668,670],{"href":669},"\u002Fglossary\u002Fboiler","Boiler",[96,672,673],{},[69,674,675],{"href":585},"Ljungström air preheater",[96,677,678],{},[69,679,680],{"href":596},"Tubular air preheater",[96,682,683],{},[69,684,231],{"href":216},[96,686,687],{},[69,688,198],{"href":110},[96,690,691],{},[69,692,203],{"href":163},{"title":205,"searchDepth":206,"depth":206,"links":694},[695,696,697,698],{"id":557,"depth":206,"text":558},{"id":611,"depth":206,"text":612},{"id":653,"depth":206,"text":654},{"id":175,"depth":206,"text":176},"boiler","An air heater — also called an air preheater (APH) — is the final heat-recovery device in a boiler's convective pass, recovering low-grade heat from cooling flue gas to preheat the combustion air. APHs lift overall boiler efficiency by 5–10 percentage points and are critical to heat-rate performance.",{},[699,703,704,370,221,222],"ljungstrom-air-preheater","tubular-air-preheater",{"title":706,"description":707},"Air heater (APH) — final flue-gas heat-recovery device before the stack","An air heater (also air preheater, APH) recovers low-grade heat from flue gas to preheat combustion air. Cold-end fouling and corrosion are the dominant operational challenges.",[709],{"title":710,"url":711},"Wikipedia — Air preheater","https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FAir_preheater","glossary\u002Fair-heater","3pBQ2ZyiQ7VOKuf9rxsx43EFarkhgykVhd2amXg0TMY",{"id":715,"title":198,"aliases":716,"body":720,"category":699,"description":820,"extension":213,"meta":821,"navigation":215,"path":110,"relatedTerms":822,"seo":825,"sources":828,"stem":830,"term":831,"__hash__":832},"glossary\u002Fglossary\u002Fcold-end-corrosion-dew-point-corrosion.md",[717,718,719],"cold end corrosion","dew point corrosion","sulphuric acid corrosion (boiler)",{"type":54,"value":721,"toc":815},[722,741,745,748,761,764,766,787,789],[57,723,724,726,727,730,731,733,734,737,738,740],{},[60,725,644],{}," (also ",[65,728,729],{},"dew-point corrosion",") is the attack on boiler ",[69,732,220],{"href":76}," baskets, ",[69,735,736],{"href":317},"economiser"," tubes and downstream ducting where flue-gas temperature falls below the ",[69,739,649],{"href":648}," of the gas. SO₃ in the flue gas combines with water vapour to form sulphuric acid that condenses on the cooled surfaces and attacks them.",[85,742,744],{"id":743},"the-interplay-with-fouling","The interplay with fouling",[57,746,747],{},"Cold-end corrosion and fouling reinforce each other:",[93,749,750,753,756],{},[96,751,752],{},"Condensed acid bonds dust to surfaces — fouling consolidates faster",[96,754,755],{},"Fouled tubes run cooler than design — more acid condenses",[96,757,758,760],{},[69,759,47],{"href":216}," deposits accelerate both processes",[57,762,763],{},"The result is a self-feeding cycle: a unit that begins to foul typically also begins to corrode, and both worsen until the cold end is water-washed or rebuilt.",[85,765,133],{"id":132},[93,767,768,773,776,779,782],{},[96,769,770,771],{},"Maintain cold-end metal temperature above the ",[69,772,649],{"href":648},[96,774,775],{},"Manage fuel sulphur and SCR SO₂\u002FSO₃ conversion",[96,777,778],{},"Use corrosion-resistant materials (Cor-Ten, enamel-coated baskets) at the cold end",[96,780,781],{},"Periodic water-washing of cold-end baskets and tubes",[96,783,784,786],{},[69,785,164],{"href":163}," to keep deposits from consolidating",[85,788,176],{"id":175},[93,790,791,795,800,804,809],{},[96,792,793],{},[69,794,193],{"href":76},[96,796,797],{},[69,798,799],{"href":317},"Economiser",[96,801,802],{},[69,803,231],{"href":216},[96,805,806],{},[69,807,808],{"href":648},"Acid dew point",[96,810,811],{},[69,812,814],{"href":813},"\u002Fglossary\u002Fboiler-tube-failure","Boiler tube failure",{"title":205,"searchDepth":206,"depth":206,"links":816},[817,818,819],{"id":743,"depth":206,"text":744},{"id":132,"depth":206,"text":133},{"id":175,"depth":206,"text":176},"Cold-end corrosion (also dew-point corrosion) is the attack on boiler air-heater baskets, economiser tubes and downstream ducting where flue-gas temperature falls below the acid dew point of the gas. SO₃ in the flue gas combines with water vapour to form sulphuric acid that condenses on the cooled surfaces and attacks them.",{},[220,736,370,823,824],"acid-dew-point","boiler-tube-failure",{"title":826,"description":827},"Cold-end corrosion — sulphuric-acid attack at the boiler's coolest point","Cold-end corrosion is the attack on air-heater and economiser surfaces below the acid dew point, where SO3 condenses as sulphuric acid. The leading cold-end failure mechanism.",[829],{"title":228,"url":229},"glossary\u002Fcold-end-corrosion-dew-point-corrosion","Cold-end corrosion and dew-point corrosion","IO_wdcX5SRjrSEY4SMku6RmkWNHXkuMTmeI4uHpz1dI",{"id":834,"title":203,"aliases":835,"body":838,"category":1038,"description":1039,"extension":213,"meta":1040,"navigation":215,"path":163,"relatedTerms":1041,"seo":1048,"sources":1051,"stem":1061,"term":203,"__hash__":1062},"glossary\u002Fglossary\u002Fsonic-horn.md",[472,836,837],"sonic cleaning horn","industrial sonic horn",{"type":54,"value":839,"toc":1031},[840,870,874,882,886,948,952,988,992,999,1001],[57,841,842,843,846,847,851,852,314,855,314,859,314,862,402,866,83],{},"A ",[60,844,845],{},"sonic horn"," is a pneumatically-driven sound emitter that produces high-intensity, low-frequency sound waves — typically between 60 and 400 Hz at sound pressure levels of 140 to 180 dB — used to dislodge particulate fouling from inside industrial process equipment. Sonic horns are the most common form of ",[69,848,850],{"href":849},"\u002Fglossary\u002Facoustic-cleaner","acoustic cleaner"," and the default specification for cleaning ",[69,853,854],{"href":618},"ESPs",[69,856,858],{"href":857},"\u002Fglossary\u002Ffabric-filter","baghouses",[69,860,861],{"href":81},"SCR catalysts",[69,863,865],{"href":864},"\u002Fglossary\u002Fsuperheater","boiler heat-transfer surfaces",[69,867,869],{"href":868},"\u002Fglossary\u002Fhopper","hoppers and silos",[85,871,873],{"id":872},"how-a-sonic-horn-works","How a sonic horn works",[57,875,876,877,881],{},"Compressed plant air admitted through a ",[69,878,880],{"href":879},"\u002Fglossary\u002Fsolenoid-valve","solenoid valve"," drives a metal diaphragm — typically titanium or 316 stainless — into resonant oscillation at the horn's fundamental frequency. The oscillating pressure field is amplified by an exponential bell horn and projected into the vessel as a near-spherical sound wave. Particulate already deposited on internal surfaces receives an oscillating acceleration that overcomes adhesion; loosened material is then carried out with the gas flow before it can sinter, bridge or bond. Because the cleaning is acoustic and non-contact, the horn can fire while the plant is online without tube erosion, refractory damage or thermal shock.",[85,883,885],{"id":884},"key-parameters","Key parameters",[560,887,888,898],{},[563,889,890],{},[566,891,892,895],{},[569,893,894],{},"Parameter",[569,896,897],{},"Typical range",[576,899,900,908,916,924,932,940],{},[566,901,902,905],{},[581,903,904],{},"Fundamental frequency",[581,906,907],{},"60–400 Hz",[566,909,910,913],{},[581,911,912],{},"Sound pressure level",[581,914,915],{},"140–180 dB",[566,917,918,921],{},[581,919,920],{},"Compressed-air consumption",[581,922,923],{},"8–14 Nm³\u002Fmin at 4–7 bar",[566,925,926,929],{},[581,927,928],{},"Operating temperature (with appropriate materials)",[581,930,931],{},"−40 °C to +500 °C",[566,933,934,937],{},[581,935,936],{},"Firing cycle",[581,938,939],{},"5–15 s burst, repeated every 3–15 minutes",[566,941,942,945],{},[581,943,944],{},"Mass",[581,946,947],{},"15–60 kg depending on horn size",[85,949,951],{"id":950},"frequency-selection","Frequency selection",[57,953,954,955,314,959,963,964,314,968,972,973,314,976,979,980,402,984,83],{},"Lower frequencies (60–125 Hz) project longer wavelengths and penetrate further into large open vessels — ",[69,956,958],{"href":957},"\u002Fglossary\u002Fpreheater-cyclone","preheater cyclones",[69,960,962],{"href":961},"\u002Fglossary\u002Frecovery-boiler","recovery-boiler superheaters",", large ",[69,965,967],{"href":966},"\u002Fglossary\u002Fesp-field-bus-section","ESP fields",[69,969,971],{"href":970},"\u002Fglossary\u002Fsilo","silos",". Higher frequencies (230–400 Hz) carry more energy per unit volume and suit finer dust loads in ",[69,974,975],{"href":857},"fabric-filter compartments",[69,977,978],{"href":503},"catalyst layers"," and smaller hopper geometries. See ",[69,981,983],{"href":982},"\u002Fglossary\u002Flow-frequency-acoustic-cleaner","low-frequency acoustic cleaner",[69,985,987],{"href":986},"\u002Fglossary\u002Fhigh-frequency-acoustic-cleaner","high-frequency acoustic cleaner",[85,989,991],{"id":990},"sonic-horn-vs-steam-sootblower","Sonic horn vs steam sootblower",[57,993,994,995,998],{},"Sonic horns are increasingly specified alongside or in place of ",[69,996,997],{"href":468},"steam sootblowers"," because they consume no boiler-grade steam, cause no tube erosion, require almost no moving parts and can fire every few minutes without operator intervention. They are less effective on hard, fused slag than retractable steam lances, so on furnace waterwalls and high-temperature superheaters they typically complement rather than replace mechanical cleaning.",[85,1000,176],{"id":175},[93,1002,1003,1008,1014,1020,1026],{},[96,1004,1005],{},[69,1006,1007],{"href":849},"Acoustic cleaner",[96,1009,1010],{},[69,1011,1013],{"href":1012},"\u002Fglossary\u002Fsonic-sootblower","Sonic sootblower",[96,1015,1016],{},[69,1017,1019],{"href":1018},"\u002Fglossary\u002Fbell-horn","Bell horn",[96,1021,1022],{},[69,1023,1025],{"href":1024},"\u002Fglossary\u002Fdiaphragm-horn","Diaphragm horn",[96,1027,1028],{},[69,1029,1030],{"href":982},"Low-frequency acoustic cleaner",{"title":205,"searchDepth":206,"depth":206,"links":1032},[1033,1034,1035,1036,1037],{"id":872,"depth":206,"text":873},{"id":884,"depth":206,"text":885},{"id":950,"depth":206,"text":951},{"id":990,"depth":206,"text":991},{"id":175,"depth":206,"text":176},"core-technology","A sonic horn is a pneumatically-driven sound emitter that produces high-intensity, low-frequency sound waves — typically between 60 and 400 Hz at sound pressure levels of 140 to 180 dB — used to dislodge particulate fouling from inside industrial process equipment. Sonic horns are the most common form of acoustic cleaner and the default specification for cleaning ESPs, baghouses, SCR catalysts, boiler heat-transfer surfaces and hoppers and silos.",{},[1042,1043,1044,1045,1046,1047],"acoustic-cleaner","acoustic-cleaning-system","sonic-sootblower","bell-horn","diaphragm-horn","low-frequency-acoustic-cleaner",{"title":1049,"description":1050},"Sonic horn — definition, frequency, SPL and industrial applications","A sonic horn is a pneumatically-driven low-frequency sound emitter (typically 60–400 Hz at 140–180 dB SPL) used to dislodge particulate fouling from boilers, ESPs, baghouses and process vessels.",[1052,1055,1058],{"title":1053,"url":1054},"Power Engineering — Sonic Horns: A User's Introduction","https:\u002F\u002Fwww.power-eng.com\u002Fcoal\u002Fsonic-horns-a-userrsquos-introduction\u002F",{"title":1056,"url":1057},"Power Engineering — Tuning in to Acoustic Cleaning","https:\u002F\u002Fwww.power-eng.com\u002Fcoal\u002Ftuning-in-to-acoustic-cleaning\u002F",{"title":1059,"url":1060},"Wikipedia — Sonic soot blowers","https:\u002F\u002Fen.wikipedia.org\u002Fwiki\u002FSonic_soot_blowers","glossary\u002Fsonic-horn","YzrhN0kKzqSaQo0wfn0rueNZ-V43mcg5zahqeWi3lnU",1782613749316]