Izixazululo Zezitshalo Ze-Asphalt Ezisetshenziswa Kanjani Kabusha Ze-RAP Zinganciphisa Kanjani Izindleko Ngaphandle Kokwehlisa Ikhwalithi?

Wake wazibuza ukuthi kungani abanye abakhi bemigwaqo beqhubeka nokuwina amabhidi kuyilapho amanani ezinto ezibonakalayo eqhubeka nokwenyuka? Imfihlo ivame ukutholakala ngaphakathi kwezixazululo zabo zezitshalo ze-asphalt ezisebenzisa kabusha i-rap - ubuchwepheshe obubuyisa kufikela ku-60% we-asphalt endala futhi bunciphise izindleko zezinto ezingavuthiwe ngesigamu. Ake sibheke amaqhinga angempela aguqula izingxenye zezindawo zokupaka ezigayiwe zibe yinzuzo. (Futhi yebo, sizophinde sichaze ushintsho olulodwa olungakongela u-$0.40 ngethani.)

Iyini ngempela i-RAP, futhi kungani ibalulekile ekukhiqizweni kwe-HMA yanamuhla?

I-Reclaimed Asphalt Pavement (RAP) ayisekho nje “imishini yokugaya”; iyinto etholakala kalula ebhange. Ithani ngalinye olisebenzisa kabusha lisho ithani elilodwa elincane le-virgin aggregate kanye ne-binder okufanele uyithenge. Ngo-2023, i-liquid AC binder yayilinganiselwa ku-$650 ngethani elifushane kulo lonke i-US Gulf Coast. Hlanganisa i-30% RAP engxubeni yakho bese ususa cishe u-$200 ngethani ngalinye le-asphalt eqediwe. Lokho kuyizibalo ngisho noma umgcini-zimali wakho uzokunika i-five five.

Zisebenza Kanjani Izixazululo Zezitshalo Ze-Asphalt Ze-Rap Zanamuhla Zokuvuselela I-Hot Mix?

Cishe uke wabona ama-drum dryer amadala ahambisanayo ashisa i-RAP njenge-toast yangozolo. Izitshalo zanamuhla ezisezingeni eliphezulu zisebenzisa amajakethi okudlulisa ukushisa aphikisanayo kanye nokususwa komswakama kwesigaba somswakama . Ukuhumusha: i-RAP ifudumala kancane, ngakho-ke i-bitumen esele "ayigugi" noma iqhekeke. Umphumela? Ingxube ehlangabezana nama-volumetric e-Superpave ngaphandle kwedrama. Amanye ama-OEM aze angeze ama-pyrometer e-infrared afunda izinga lokushisa elihlanganisiwe ngesikhathi sangempela, elungisa ngokuzenzakalelayo i-RAP feed ukuze ihlale ngaphakathi kuka-±3 °C wethagethi. Ibushelelezi impela, akunjalo?

Ukuthuthukiswa Kwehadiwe Okubalulekile Okuzikhokhela Ezinyangeni Eziyi-18

• Ama-conveyor e-drag slat aguquguqukayo : Anciphisa ukudonsa kwamahhashi ngo-25% futhi anciphise ukuwohloka kwe-RAP.
• Izihlukanisi ze-venturi ezine-steam ephezulu : Khipha umswakama ongu-80% ngaphambi kokuba i-RAP ishaye isigubhu, okusindisa uphethiloli wesishisi.
• I-pugmill enama-shaft amabili enokugcinwa kwemizuzwana eyi-15 : Iqeda intuthu eluhlaza okwesibhakabhaka futhi igcine omakhelwane bakho bejabule.

Ungakwazi Yini Ukudlula I-RAP Engu-40% Ngaphandle Kokulimaza Ukusebenza Kwezinga Eliphansi Lokushisa?

Impendulo emfushane: yebo, kodwa kufanele udlale i-chemist. I-Soft-grade virgin binder (PG 58-28) kanye ne-0.3% Sasobit noma i-warm-mix additive efanayo yehlisa izinga lokushisa eliphezulu elisebenzayo ngesinyathelo esisodwa kuphela ngenkathi ibuyisela izinga lokushisa eliphansi ngezinyathelo ezimbili. Umshayeli we-Illinois DOT ka-2022 ku-I-72 usebenzise i-45% RAP ngaleyo ndlela eqondile futhi wadlula i-TSR (isilinganiso samandla okudonsa) ku-85%. Ngakho-ke, akusekho izaba "esingenakukwazi ukuya phezulu kune-25%", bantu.

Kuthiwani Ngezikhisi Ezikhipha Umoya? Ingabe Abalawuli Bazongivala?

Imikhawulo ye-EPA MACT ye-PM2.5 ingu-0.04 gr/dscf. Isitshalo esifakwe isikhwama se-reverse-pulse kanye nomjovo we-dry lime siwela kalula ku-0.01 gr/dscf ngisho noma okuqukethwe yi-RAP kufinyelela ku-50%. Icebiso lochwepheshe: sebenzisa isivivinyo sekota ye-stack ebusika—ubuningi bomoya obandayo bungaphazamisa ukufundwa, futhi awufuni ukucashelwa ukwephulwa kokungabonakali kahle ngaphambi nje kwesizini yokugandaya.

I-ROI Efihliwe: Izinhlawulo ze-Baghouse njenge-Mineral Filler

Esikhundleni sokugcwalisa lezo zinhlawulo ezinothuli, buyisela u-1–2% engxubeni. Kungumshini wokugcwalisa wamahhala okhulisa i-VMA ngo-0.5% futhi ukuvumela ukuthi usule uthuli lwe-limestone oluyi-virgin. Isitshalo esisodwa se-200-tph esisihlolile eGeorgia songe u-$42 k ngonyaka kulokhu kulungiswa. Akuyona nje inguquko eningi, akunjalo?

Indlela Yokuvikela Isitshalo Sakho Esikhathini Esizayo Ukuze Sithole I-RAP Engu-60%

Qala ngesigubhu esinemigqomo emibili esihlukanisa i-RAP endaweni yomlilo oqondile. Engeza indawo yokungena ye-RAP eguquguqukayo - yisondeze eduze noma kude nesishisi kuye ngomswakama. Okokugcina, cacisa i -recycle feeder enempendulo ye-weigh-bridge ukuze uhlelo lokulawula izitshalo lukwazi ukulungisa ngokuzenzakalelayo ukukhukhuleka kwamathani. Lezi zinyathelo ezintathu zikulungiselela noma yini i-DOT ezoyiphonsa kuwe eminyakeni eyishumi ezayo.

Ucwaningo Lwecala: Umgwaqo Omkhulu Wesifundazwe Ongama-38-Mile eColorado

Iphrojekthi yayidinga ama-tani angu-110 000 we-SMA engu-12.5-mm. I-Spec ibeke i-RAP ku-30%, kodwa unkontileka ubhide ku-40% esebenzisa ukusethwa okungenhla. Ukonga okuphelele: $1.9 M. Okubaluleke kakhulu? Ukusebenza kwe-pavement ngemuva kwezinkathi ezimbili zokuncibilika kweqhwa kuthole amaphuzu angu-92 ku-PCR (isilinganiso sesimo se-pavement) uma kuqhathaniswa no-88 wesigaba sokulawula esine-virgin mix. Ngisho nonjiniyela we-pavement wesifundazwe uvumile, “Asikubonanga lokho kuza.”

Izinganekwane Ezivamile Ziyaphikiswa

Inganekwane: “Izingxube ze-High-RAP zihlala zingasebenzi.”

Iqiniso: Ukugoba kuncike esakhiweni esihlanganisiwe, hhayi iphesenti le-RAP. Sebenzisa isilinganiso se-CA/FA esilinganiswe kahle esiseduze no-0.45 futhi uzoba kahle.

Inganekwane: “I-RAP iqukethe ama-hydrocarbon angaziwa anuka kabi.”

Yebo, impela, uma usebenzisa isitofu sakho esinophethiloli obuningi kanye namazinga okushisa enyakatho ka-340 °C. Gcina izinga lokushisa le-stack lingaphansi kuka-160 °C futhi iphunga lehla liye ezingeni le-BBQ yendawo.

Uhlu Lokuhlola Olusheshayo Ngaphambi Kokuthi Uphinde Ulungise

1. Qinisekisa ukuthi ama-silo akho angakwazi ukusingatha ivolumu eyengeziwe yezinto ezibonakalayo engu-10% (i-RAP ithambile kakhulu).
2. Thuthukisa ama-trunnion; ama-RAP drums agijima imithwalo esindayo.
3. Khuluma ne-DOT yakho kusenesikhathi—ezinye izifundazwe zisabeka i-RAP ku-25% ye-SMA, kodwa nikeza ukuxolelwa uma ubonisa idatha yelabhorethri.

Ukulungele ukukhipha yonke imali yokugcina ezitolo zakho ze-rap recycling hot mix asphalt plants? Qala nge-moisture probe, engeza i-VFD ku-RAP feed, bese ubheka indlela yakho yokonga ishintsha ibe yi-hockey-stick. Futhi, uma udinga ukucwila ngokujulile ekuthungeni izitofu noma ekulinganisweni okungeziwe, sitshele—ukuhamba okuhle!