Abacimi-mlilo basebenzisa igwebu elenza umbane elenza iFilimu (i-AFFF) ukunceda ukucima imililo enzima ukulwa imililo, ngakumbi imililo ebandakanya ipetroleum okanye ezinye izinto ezingamanzi ezinokutsha ezaziwa ngokuba yimililo yeBanga B. Nangona kunjalo, ayizizo zonke iigwebu zokucima umlilo ezihlelwa njenge-AFFF.

Ezinye iifom ze-AFFF zineklasi yeekhemikhali ezaziwa njenge Iiperfluorochemicals (PFCs) kwaye oku kunyuse inkxalabo malunga nokubanakho ungcoliseko lwamanzi aphantsi komhlaba imithombo evela ekusetyenzisweni kweearhente ze-AFFF eziqulathe ii-PFC.

Ngo-Meyi 2000, i Inkampani ye3M ithe ayizukuphinda ivelise i-PFOS (i-perfluorooctanesulphonate) -based flurosurfactants esebenzisa inkqubo ye-electrochemical flouorination. Ngaphambi koku, ezona PFC zixhaphakileyo ezazisetyenziswa kumagwebu okucima umlilo yayiyi-PFOS kunye nezinto ezazivela kuyo.

I-AFFF icima ngokukhawuleza umlilo wamafutha, kodwa iqulethe i-PFAS, emele izinto ze-per kunye ne-polyfluoroalkyl. Olunye ungcoliseko lwePFAS lubangelwa kukusetyenziswa kwegwebu lokucima umlilo. (Ifoto / Isiseko esihlangeneyo iSan Antonio)

AMANQAKU Ahambelana

Ukujonga 'okuqhelekileyo okutsha' kwezixhobo zomlilo

Umjelo onetyhefu 'wegwebu eliyimfihlakalo' kufutshane neDetroit yayiyi-PFAS- kodwa isuka phi?

Igwebu lomlilo elisetyenziselwa uqeqesho eConn. Linokubangela impilo enkulu, umngcipheko kwindalo esingqongileyo

Ngexesha leminyaka embalwa edlulileyo, imboni yecwecwe lokucima umlilo isukile kwi-PFOS nakwiziphumo zayo ngenxa yoxinzelelo lowiso-mthetho. Abo bavelisi baphuhlisile kwaye bazise kwintengiso yegwebu lokucima umlilo elingasebenzisi zekhemikhali zeekhemikhali, oko kukuthi, ezingenasimahla.

Abavelisi begwebu elingena fluorine bathi ezi foam zinempembelelo encinci kwindalo kwaye ziyahlangabezana neemvume zamanye amazwe kwiimfuno zokulwa umlilo kunye nokulindelwa ngabasebenzisi bokugqibela. Nangona kunjalo, kusaqhubeka ukuxhalaba kokusingqongileyo malunga namagwebu okucima umlilo kunye nophando ngesihloko siyaqhubeka.

UKUKHATHAZEKA NGOKUSETYENZISWA KWENKCUBEKO?

Iziko lezinto ezixhalabisayo lijikeleze ifuthe elibi kwimo engqongileyo ukusuka ekukhutshweni kwezisombululo zegwebu (indibaniselwano yamanzi kunye nokugxila kugwebu) Eyona micimbi iphambili bubutyhefu, ukungonakali kwebhayoloji, ukuzingisa, ukunyangwa kwizityalo zokucoca amanzi amdaka kunye nokulayishwa kwezondlo zomhlaba. Zonke ezi zinto zibangela inkxalabo xa isisombululo se-foam sifikelela Iinkqubo zamanzi zendalo okanye zasekhaya.

Xa i-PFC iqulethe i-AFFF iphinda isetyenziswe kwindawo enye ixesha elide, ii-PFCs zinokuhamba zisuka kumagwebu zingene emhlabeni emva koko ziye emanzini angaphantsi komhlaba. Isixa see-PFCs ezingena emanzini aphantsi komhlaba sixhomekeke kuhlobo kunye nenani le-AFFF esetyenzisiweyo, apho lalisetyenziswa khona, uhlobo lomhlaba kunye nezinye izinto.

Ukuba imithombo yabucala okanye kawonke-wonke ikufuphi, banokuchaphazeleka zii-PFCs ukusuka apho bekusetyenziswa khona i-AFFF. Nanku ukujonga okwapapashwa liSebe lezeMpilo laseMinnesota; lelinye lamazwe aliqela ukuvavanya ukungcoliseka.

“Ngo-2008-2011, i-Arhente yoLawulo loNgcoliseko eMinnesota (MPCA) yavavanya umhlaba, amanzi aphezu komhlaba, amanzi aphantsi komhlaba, kunye neentsika kwiindawo ezikufutshane nase-13 ze-AFFF kurhulumente. Bafumanise amanqanaba aphezulu ee-PFC kwezinye zeendawo, kodwa kwiimeko ezininzi ukungcoliseka akuchaphazeli indawo enkulu okanye kubeka umngcipheko ebantwini okanye kwindalo esingqongileyo. Iindawo ezintathu-iDuluth Air National National Base Base, iBemidji Airport, kunye ne-Western Area Training Training Academy-zichongiwe apho ii-PFC zisasazeke ngokwaneleyo kangangokuba iSebe lezeMpilo laseMinnesota kunye ne-MPCA bagqibe kwelokuvavanya imithombo yokuhlala ekufuphi.

“Oku kunokwenzeka kakhulu kufutshane neendawo apho i-PFC iqulethe i-AFFF isetyenziswe ngokuphindaphindiweyo, njengeendawo zoqeqesho lomlilo, izikhululo zeenqwelo moya, iindawo zokucoca, kunye nezityalo zamachiza. Kunqabile ukuba kwenzeke kusetyenziso lwexesha elinye lwe-AFFF ukulwa umlilo, ngaphandle kokuba kusetyenziswa izixa ezikhulu ze-AFFF. Nangona ezinye izicimi-mlilo eziphathwayo zisenokusebenzisa i-PFF equlethwe yi-PFF, ukusebenzisa isixa esincinci kunokubangela ingozi kumanzi aphantsi komhlaba. ”

UKUHLAWULWA KWENKONZO

Ukukhutshwa kwesisombululo segwebu / samanzi kunokuba sisiphumo sinye okanye ezingaphezulu kwezi meko zilandelayo:

  • Umsebenzi wokucima umlilo okanye wokufaka ingubo kwipetroli;
  • Ukuzivocavoca uqeqesho apho amagwebu asetyenziswa khona;
  • Inkqubo yezixhobo ze-foam kunye novavanyo lwezithuthi; okanye
  • Ukukhutshwa kwenkqubo ehleliweyo.

Iindawo apho enye okanye ezininzi zeziganeko zinokwenzeka khona zibandakanya izixhobo zeenqwelomoya kunye namaziko oqeqesho lwabacimi-mlilo. Izixhobo ezizodwa ezinobungozi, ezinjengezinto zokugcina ezinokutsha / ezinobungozi, iindawo zokugcina izinto ezinokutsha ezingamanzi kunye neendawo zokugcina inkunkuma eyingozi, nazo zenza uluhlu.

Kuyinto enqwenelekayo kakhulu ukuqokelela izisombululo ze-foam emva kokusetyenziswa kwayo kwimisebenzi yokucima umlilo. Ngaphandle kwecandelo le-foam ngokwalo, igwebu kunokwenzeka ukuba lingcoliswe sisibaso okanye i-fuels ebandakanyeka emlilweni. Isiganeko esinezixhobo ezinobungozi esiqhelekileyo siphelile ngoku.

Izicwangciso zokuqulatha ngesandla ezisetyenziselwa ukuchitheka kubandakanya ulwelo olunobungozi kufuneka zisetyenziswe xa iimeko kunye nemvume yokusebenza. Oku kubandakanya ukuvala imijelo yesiphepho ukuthintela ukungcoliseka kwefom / isisombululo samanzi ukuba singangeni kwinkqubo yamanzi amdaka okanye kwindalo esingakhange siqwalaselwe.

Iindlela zokuzikhusela ezinje ngokuthambisa, ukumisa amanzi kunye nokuphambukisa kufuneka zisetyenziselwe ukufumana isisombululo segwebu / samanzi kwindawo efanelekileyo yokuthintela kude kube kususwe ikontraka eyingozi yokucoca izixhobo.

UKUQEQESHA NGENQOLA

Kukho iifom zoqeqesho ezilungiselelwe ngokukodwa ezifumanekayo kubavelisi abaninzi begwebu abalinganisa i-AFFF ngexesha loqeqesho olusebenzayo, kodwa awanazo izinto ezenziwayo njenge-PFC. Ezi foam zoqeqesho zihlala zibola kwaye zinempembelelo encinci kwindalo esingqongileyo; Banokuthunyelwa ngokukhuselekileyo kwiziko lokucoca amanzi amdaka lasekuhlaleni ukuze lisetyenzwe.

Ukungabikho kwee-flourosurfactants kuqeqesho lwegwebu kuthetha ukuba ezo foams zinonciphiso lokutsha kwakhona. Umzekelo, igwebu loqeqesho liza kubonelela ngesithintelo sokuqala somphunga kulwelo olunokutsha olunamanzi olukhokelela ekucimeni, kodwa loo ngubo igwebu iya kuphuka ngokukhawuleza.

Yinto elungileyo evela kumbono womyaleli njengoko oko kuthetha ukuba ungaqhuba ngakumbi uqeqesho kuba wena kunye nabafundi bakho anilindelanga ukuba uqeqesho lwe-simulator ukuba lutshe kwakhona.

Ukuzivocavoca uqeqesho, ngakumbi abo basebenzisa amagwebu agqityiweyo, kufuneka babandakanye amalungiselelo okuqokelela amagwebu asetyenzisiweyo. Ubuncinci, amaziko oqeqesho lomlilo kufuneka abenakho ukuqokelela isisombululo segwebu esisetyenzisiweyo kwimeko zoqeqesho zokukhuphela kwindawo yokucoca amanzi amdaka.

Phambi kokukhutshwa, indawo yokucoca amanzi amdaka kufuneka yaziswe kwaye kunikwe imvume kwisebe lomlilo ukuba iarhente ikhutshwe kwinqanaba elimiselweyo.

Ngokuqinisekileyo ukuphuhliswa kweenkqubo zokungeniswa kwi-Class A foam (kwaye mhlawumbi i-arhente ye-chemistry) iya kuqhubeka ukuqhubela phambili njengoko injalo kule minyaka ilishumi idlulileyo. Kodwa ngokubhekisele kwi-foam B egxila kwi-foam, iinzame zokuphucula i-chemistry iinzame zibonakala ngathi ziye zaqina ngexesha kunye nokuxhomekeka kubuchwepheshe obusisiseko.

Ukusukela oko kwaqaliswa imimiselo yokusingqongileyo kule minyaka ilishumi idlulileyo okanye njalo kwi-AFFFs esekwe kwi-fluorine apho abavelisi begwebu abacima umlilo bawuthatha ngokungxamisekileyo umngeni wophuhliso. Ezinye zezi mveliso zingena fluorine zizukulwana zokuqala kwaye ezinye zivelise isibini okanye isithathu.

Baza kuqhubeka nokuvela kuzo zombini i-arhente chemistry kunye nokusebenza kokucima umlilo ngenjongo yokufezekisa ukusebenza okuphezulu kulwelo olunokutsha nolutsha, ukuphucuka kokumelana nokubuyela umva kukhuseleko lwabacimi-mlilo kunye nokubonelela iminyaka emininzi eyongezelelweyo yobomi beshelfu ngaphezulu kwamagwebu avela kwiprotein. 


Ixesha lokuposa: Aug-27-2020