Plastiki emhlabeni

Ngo-2050, isisindo semfucumfucu yepulasitiki olwandle sizodlula isisindo sezinhlanzi ezihlangene! Isexwayiso esinjalo safakwa embikweni we-Ellen MacArthur Foundation kanye noMcKinsey oshicilelwe emcimbini weWorld Economic Forum eDavos ngo-2016.

Njengoba sifunda kulo mbhalo, isilinganiso samathani epulasitiki kuya amathani ezinhlanzi emanzini olwandle ngo-2014 kwakuyiyodwa kuya kwemihlanu. Ngo-2025, kuzoba khona oyedwa kwabathathu, futhi ngo-2050 kuzoba nemfucuza yepulasitiki ... Lo mbiko wawusekelwe ezingxoxweni nochwepheshe abangaphezu kuka-180 kanye nokuhlaziywa kwezinye izifundo ezingaphezu kwamakhulu amabili. Ababhali balo mbiko baphawula ukuthi yi-14% kuphela yamaphakethe epulasitiki agaywa kabusha. Kwezinye izinto ezisetshenziswayo, izinga lokugaywa kabusha lihlala liphezulu kakhulu, lithola u-58% wephepha kanye nokufika ku-90% wensimbi nensimbi.

1. Ukukhiqizwa komhlaba wonke kwamapulasitiki ngo-1950-2010

Ngenxa yokusebenziseka kwayo kalula, ukuguquguquka futhi ngokusobala, isiphenduke enye yezinto ezisetshenziswa kakhulu emhlabeni. Ukusetshenziswa kwayo kukhule cishe ngokuphindwe kangamakhulu amabili ukusuka ku-1950 kuya ku-2000 (1) futhi kulindeleke ukuthi kuphindeke kabili eminyakeni engamashumi amabili ezayo.

2. Isithombe esivela ePharadesi lasePacific eziqhingini zaseTuvalu

. Siyithola emabhodleleni, kuma- foil, kumafreyimu amafasitela, ezingutsheni, emishinini yekhofi, ezimotweni, kumakhompyutha nasemakhejini. Ngisho ne-turf yebhola lezinyawo ifihla imicu yokwenziwa phakathi kwezindwani zemvelo zotshani. Izikhwama zepulasitiki nezikhwama ngezinye izikhathi ezidliwa izilwane ngephutha zilahlwa emigwaqweni nasemasimini (2). Ngokuvamile, ngenxa yokuntuleka kokunye, imfucumfucu yepulasitiki iyashiswa, ikhiphe intuthu enobuthi emkhathini. Imfucumfucu yepulasitiki ivala indle, ibangele izikhukhula. Zivimbela ukuhluma kwezitshalo kanye nokumuncwa kwamanzi emvula.

3. Ufudu ludla ucwecwe lwepulasitiki

Izinto ezincane kakhulu zimbi kakhulu

Abacwaningi abaningi baphawula ukuthi udoti wepulasitiki oyingozi kakhulu akuwona amabhodlela e-PET antanta olwandle noma izigidigidi zezikhwama zepulasitiki eziwayo. Inkinga enkulu yizinto esingaziboni ngempela. Lena imicu yepulasitiki emincane elukwe engutsheni yezingubo zethu. Inqwaba yezindlela, amakhulu emigwaqo, enqamula indle, imifula, ngisho nasemkhathini, ingena emvelweni, ingene emaketangeni okudla ezilwane nabantu. Ukulimaza kwalolu hlobo lokungcola kufinyelela izinga lezinhlaka zamaselula kanye ne-DNA!

Ngeshwa, imboni yezingubo, okulinganiselwa ukuthi izocubungula amathani ayizigidi eziyizinkulungwane ezingama-70 alolu hlobo lwefayibha ibe yizicucu zezingubo eziyizigidi eziyizinkulungwane eziyi-150, empeleni ayilawulwa nganoma iyiphi indlela. Abakhiqizi bezingubo abekho ngaphansi kwemikhawulo eqinile kanye nezilawuli ezifana nokupakishwa kwepulasitiki noma amabhodlela e-PET ashiwo ngenhla. Kuncane okushiwoyo noma okubhaliwe mayelana neqhaza labo ekungcolisweni kwepulasitiki emhlabeni. Azikho futhi izinqubo eziqinile futhi ezisungulwe kahle zokulahlwa kwezingubo ezihlanganiswe nemicu eyingozi.

Inkinga ehlobene futhi engekho ngaphansi yilokho okubizwa ngokuthi ipulasitiki microporous, okungukuthi, izinhlayiya zokwenziwa ezincane ezingaphansi kuka-5 mm ngosayizi. Ama-granules avela emithonjeni eminingi - amapulasitiki aphuka emvelweni, ekukhiqizeni amapulasitiki, noma inqubo yokuhuzuka kwamasondo emoto ngesikhathi sokusebenza kwawo. Ngenxa yokusekelwa kwesenzo sokuhlanza, izinhlayiya ze-microplastic zingatholakala ngisho nakuma-toothpastes, ama-gel okugeza kanye nemikhiqizo yokucwenga. Ngendle, bangena emifuleni nasezilwandle. Izikhungo eziningi ezijwayelekile zokuhlanza indle azikwazi ukubabamba.

Ukunyamalala okwesabekayo kwemfucuza

Ngemuva kocwaningo lwango-2010-2011 olwenziwa uhambo lwasolwandle olubizwa ngokuthi i-Malaspina, kwatholakala ngokungalindelekile ukuthi kunodoti wepulasitiki omncane kakhulu olwandle kunokuba bekucatshangwa. Izinyanga. Ososayensi babethembele ekubambeni okungalinganisa inani lepulasitiki yasolwandle ezigidini zamathani. Khonamanjalo, umbiko wocwaningo owavela kujenali Proceedings of the National Academy of Sciences ngo-2014 ukhuluma mayelana… 40. iphimbo. Ososayensi bakutholile lokho U-99% wepulasitiki okufanele intande emanzini olwandle ayikho!

4. Ipulasitiki nezilwane

Konke kuhamba kahle? Lutho neze. Ososayensi baqagela ukuthi upulasitiki olahlekile usungene ohlelweni lokudla olwandle. Ngakho-ke: udoti udliwa kakhulu yizinhlanzi nezinye izinto eziphilayo zasolwandle. Lokhu kwenzeka ngemva kokuhlukana ngenxa yesenzo selanga namagagasi. Khona-ke izingcezu ezincane zezinhlanzi ezintantayo zingadideka nokudla kwazo - izilwane zasolwandle ezincane. Imiphumela yokudla izingcezu ezincane zepulasitiki nokunye ukuxhumana nepulasitiki ayikaqondwa kahle, kodwa cishe akuwona umphumela omuhle (4).

Ngokwezilinganiso eziguquguqukayo ezishicilelwe kumagazini iSayensi, amathani angaphezu kwezigidi ezi-4,8 emfucumfucu yepulasitiki engena olwandle minyaka yonke. Nokho, ingafinyelela amathani ayizigidi ezingu-12,7. Ososayensi abaqhuba lezi zibalo bathi uma isilinganiso sesilinganiso sabo singamathani angaba yizigidi ezingu-8, lelo nani lemfucumfucu lingahlanganisa iziqhingi ezingu-34 ezilingana neManhattan ongqimbeni olulodwa.

Ababhali abakhulu balezi zibalo ngososayensi baseNyuvesi yaseCalifornia eSanta Barbara. Phakathi nomsebenzi wabo, basebenzisane nezinhlangano zikahulumeni zase-US namanye amanyuvesi. Iqiniso elithakazelisayo liwukuthi ngokwalezi zilinganiso, kuphela kusuka ku-6350 kuya ku-245 ayizinkulungwane. amathani epulasitiki asakaza ulwandle antanta phezu kwamanzi olwandle. Abanye bakwezinye izindawo. Ngokusho kososayensi, kokubili olwandle nasogwini futhi, yebo, ezilwaneni eziphilayo.

Sinedatha entsha nakakhulu futhi esabisa nakakhulu. Ngasekupheleni konyaka odlule, i-Plos One, inqolobane ye-inthanethi yezinto zesayensi, yanyathelisa iphepha lokusebenzisana labacwaningi abavela ezikhungweni zesayensi ezingamakhulu amaningi abalinganisela ingqikithi yemfucumfucu yepulasitiki entanta phezu kwezilwandle zomhlaba ngamathani angu-268! Ukuhlola kwabo kusekelwe kudatha evela ohambweni lwama-940 olwenziwa ngo-24-2007. emanzini ashisayo naseMedithera.

"Amazwekazi" (5) emfucumfucu yepulasitiki awamile. Ngokusekelwe ekufanisweni ukuhamba kwemisinga yamanzi olwandle, ososayensi bakwazi ukuthola ukuthi azibuthani endaweni eyodwa - kunalokho, zithuthwa amabanga amade. Njengomphumela wesenzo somoya phezu kolwandle kanye nokujikeleza koMhlaba (ngamandla okuthiwa yi-Coriolis), ama-vortices amanzi akhiwa emizimbeni emihlanu emikhulu yeplanethi yethu - i.e. iNyakatho neNingizimu Pacific, iNyakatho neNingizimu ye-Atlantic kanye ne-Indian Ocean, lapho zonke izinto zepulasitiki ezintantayo kanye nemfucuza kunqwabelana kancane kancane. Lesi simo siphindaphindwa njalo ngonyaka.

5. Imephu yokusatshalaliswa kwemfucumfucu yepulasitiki olwandle lwamasayizi ahlukene.

Ukujwayelana nemizila yokufuduka yalawa "mazwekazi" kuwumphumela wokulingisa okude kusetshenziswa amathuluzi akhethekile (ngokuvamile awusizo ocwaningweni lwesimo sezulu). Indlela elandelwa izigidi ezimbalwa zemfucuza yepulasitiki iye yacutshungulwa. Ukumodela kubonise ukuthi ezakhiweni ezakhiwe endaweni engamakhilomitha ayizinkulungwane ezingamakhulu amaningana, kwakukhona ukugeleza kwamanzi, okuthatha ingxenye yemfucuza ngaphezu kokugxiliswa kwayo okuphezulu futhi kuyiqondise empumalanga. Yiqiniso, kunezinye izici ezifana namandla amaza namandla omoya angazange acatshangelwe lapho kulungiselelwa isifundo esingenhla, kodwa ngokuqinisekile adlala indima ebalulekile ngesivinini nasendleleni yokuhamba ngepulasitiki.

Lawa "mazwe" emfucumfucu futhi ayizimoto ezinhle kakhulu zezinhlobo ezahlukahlukene zamagciwane namagciwane, angasakazeka kalula.

Indlela yokuhlanza "amazwekazi kadoti"

Ingaqoqwa ngesandla. Udoti wepulasitiki uyisiqalekiso kwabanye, futhi ungumthombo wemali kwabanye. zididiyelwa ngisho nayizinhlangano zamazwe ngamazwe. Abaqoqi Bezwe Lesithathu ipulasitiki ehlukile ekhaya. Basebenza ngesandla noma ngemishini elula. Amapulasitiki acutshungulwa noma anqunywe abe yizicucu ezincane futhi athengiswa ukuze kuqhutshekwe nokucubungula. Abaxhumanisi phakathi kwabo, abaphathi kanye nezinhlangano zomphakathi yizinhlangano ezikhethekile. Lokhu kubambisana kunikeza abaqoqi iholo elizinzile. Ngesikhathi esifanayo, kuyindlela yokukhipha imfucuza yepulasitiki emvelweni.

Nokho, ukuqoqwa okwenziwa ngesandla akusebenzi kahle. Ngakho-ke, kunemibono yemisebenzi yokuvelela eyengeziwe. Isibonelo, inkampani yaseDutch iBoyan Slat, njengengxenye yephrojekthi ye-The Ocean Cleanup, inikeza ukufakwa kwezinqamuleli zikadoti ezintantayo olwandle.

Indawo yokuqoqa imfucuza engumshayeli eduze kwaseTsushima Island, ephakathi kweJapan neKorea, ibe yimpumelelo enkulu. Ayinikwa amandla yinoma yimiphi imithombo yamandla yangaphandle. Ukusetshenziswa kwayo kusekelwe olwazini lwemiphumela yomoya, imisinga yolwandle namagagasi. Imfucumfucu yepulasitiki entantayo, ebanjwe ogibeni olugobile ngendlela ye-arc noma i-slot (6), iqhutshelwa phambili endaweni lapho inqwabelana khona futhi ingasuswa kalula. Manje njengoba isixazululo sesihloliwe ngezinga elincane, kuzodingeka kwakhiwe ukufakwa okukhulu, ngisho namakhilomitha ayikhulu ubude.

6. Ukuqoqwa kukadoti wepulasitiki ontantayo njengengxenye yephrojekthi ye-The Ocean Cleanup.

Umsunguli odumile kanye nosozigidi uJames Dyson wasungula le phrojekthi eminyakeni embalwa edlule. I-MV Recyclonenoma isicoci se-vacuum esihle kakhuluomsebenzi wabo kuzoba ukuhlanza amanzi olwandle kudoti, ikakhulukazi ipulasitiki. Umshini kufanele ubambe udoti ngenethi bese uwumunca ngezicoci ezine ze-centrifugal. Umqondo uwukuthi ukumuncwa kufanele kwenzeke ngaphandle kwamanzi futhi kungabi engozini izinhlanzi. U-Dyson ungumklami wemishini yezimboni yaseNgilandi, owaziwa kakhulu njengomsunguli we-bagless cyclone vacuum cleaner.

Futhi yini okufanele uyenze ngale nqwaba yemfucumfucu, lapho usenesikhathi sokuyiqoqa? Imibono ayishodi. Isibonelo, uDavid Katz waseCanada uphakamisa ukudala imbiza yepulasitiki ().

Udoti kungaba uhlobo lwemali lapha. Angashintshwa ngemali, izingubo, ukudla, ama-mobile top-ups, noma iphrinta ye-3D., okuyinto, futhi, ikuvumela ukuthi udale izinto ezintsha zasendlini kusuka epulasitiki esetshenziswe kabusha. Lo mbono usuze wasetshenziswa naseLima, inhloko-dolobha yasePeru. Manje uKatz uhlose ukuthakazelisa iziphathimandla zaseHaiti kuye.

Ukugaywa kabusha kuyasebenza, kodwa hhayi konke

Igama elithi "ipulasitiki" lisho izinto zokwakha, ingxenye eyinhloko yama-polymers okwenziwa, emvelo noma ashintshiwe. Amapulasitiki angatholakala kokubili kuma-polymers ahlanzekile nakuma-polymers alungiswe ngokwengezwa kwezinto ezisizayo ezihlukahlukene. Igama elithi "ipulasitiki" ngolimi oluxubile futhi lihlanganisa imikhiqizo eseqedile ukucutshungulwa kanye nemikhiqizo eqediwe, inqobo nje uma yenziwe ngezinto ezingahlukaniswa njengepulasitiki.

Kukhona cishe izinhlobo ezingamashumi amabili ezijwayelekile zepulasitiki. Ngayinye iza ngezinketho eziningi zokukusiza ukhethe izinto ezingcono kakhulu zohlelo lwakho lokusebenza. Kunamaqembu amahlanu (noma ayisithupha). amapulasitiki amaningi: i-polyethylene (PE, kufaka phakathi ukuphakama okuphezulu nokuphansi, i-HD ne-LD), i-polypropylene (PP), i-polyvinyl chloride (PVC), i-polystyrene (PS) ne-polyethylene terephthalate (PET). Lokhu okubizwa ngokuthi ama-big amahlanu noma ayisithupha (7) ahlanganisa cishe u-75% wesidingo saseYurophu sawo wonke amapulasitiki futhi simele iqembu elikhulu kunawo wonke lamapulasitiki athunyelwa ezindaweni zokulahla imfucumfucu kamasipala.

Ukulahlwa kwalezi zinto ngo ukusha ngaphandle akwamukelwe yibo bobabili ochwepheshe kanye nomphakathi jikelele. Ngakolunye uhlangothi, izishisi zokushiswa kwemvelo ezinobungani bemvelo zingasetshenziselwa le njongo, zehlise imfucuza ngama-90%.

Ukugcinwa kukadoti ezindaweni zokulahla imfucuza akuwona ubuthi njengokuwashisela ngaphandle, kodwa akusamukelwa emazweni amaningi asethuthukile. Nakuba kungelona iqiniso ukuthi "ipulasitiki ihlala isikhathi eside," ama-polymers athatha isikhathi eside ukubola kunokudla, iphepha, noma imfucuza yensimbi. Isikhathi eside ngokwanele ukuthi, isibonelo, ePoland ezingeni lamanje lokukhiqizwa kukadoti wepulasitiki, okungamakhilogremu angama-70 umuntu ngamunye ngonyaka, futhi ngezinga lokubuyisela kuze kube muva nje lidlule ngokulambisa ku-10%, inqwaba yasekhaya yalo mfucu izofinyelela amathani ayizigidi ezingama-30 esikhathini esingaphezudlwana nje kweshumi leminyaka..

Izinto ezifana nemvelo yamakhemikhali, ukuchayeka (UV) kanye, vele, ukuhlukana kwezinto kuthinta ukubola kancane kwepulasitiki. Ubuchwepheshe obuningi bokugaywa kabusha (8) buthembela nje ekusheshiseni lezi zinqubo. Ngenxa yalokho, sithola izinhlayiya ezilula ezivela kuma-polymers esingakwazi ukuzibuyisela emuva zibe izinto zezinye izinto, noma izinhlayiya ezincane ezingasetshenziswa njengezinto zokusetshenziswa ze-extrusion, noma singaya ezingeni lamakhemikhali - le-biomass, amanzi, izinhlobo ezihlukahlukene. amagesi, i-carbon dioxide, i-methane, i-nitrogen.

8. Ubuchwepheshe bokugaywa kabusha kanye nokucubungula amapulasitiki

Indlela yokulahla imfucuza ye-thermoplastic ilula, njengoba ingaphinda igaywe kaningi. Kodwa-ke, ngesikhathi sokucubungula, ukuwohloka kwengxenye ye-polymer kwenzeka, okuholela ekuwohlokeni kwezakhiwo zemishini yomkhiqizo. Ngalesi sizathu, iphesenti elithile kuphela lezinto ezigaywe kabusha zengezwa enqubweni yokucubungula, noma imfucuza icutshungulwa ibe yimikhiqizo enezidingo eziphansi zokusebenza, njengamathoyizi.

Inkinga enkulu kakhulu lapho kulahlwa imikhiqizo ye-thermoplastic esetshenzisiwe isidingo sokuhlunga ngokobubanzi, obudinga amakhono ochwepheshe kanye nokususwa kokungcola kubo. Lokhu akuzuzisi ngaso sonke isikhathi. Amapulastiki enziwe ngama-polymer axhumene kakhulu ngokomthetho awakwazi ukuphinda asetshenziswe.

Zonke izinto eziphilayo ziyavutha, kodwa futhi kunzima ukuzibhubhisa ngale ndlela. Le ndlela ayikwazi ukusetshenziselwa izinto eziqukethe isulfure, halogens ne-phosphorus, ngoba lapho zishiswa, zikhulula emkhathini inani elikhulu lamagesi anobuthi, okuyimbangela yalokho okubizwa ngokuthi imvula ye-asidi.

Okokuqala, kukhishwa ama-organochlorine ama-aromatics compounds, ubuthi obuphakeme izikhathi eziningi kune-potassium cyanide, nama-hydrocarbon oxides ngendlela ye-dioxanes - C.₄H₈O₂ futhi furanov - C₄H₄Mayelana nokukhululwa emkhathini. Zinqwabelana endaweni ezungezile kodwa kunzima ukuzibona ngenxa yokugcwala okuphansi. Ukumuncwa ukudla, umoya namanzi futhi kunqwabelana emzimbeni, kubangela izifo ezinzima, kunciphise amasosha omzimba, kubangele umdlavuza futhi kungabangela izinguquko zofuzo.

Umthombo oyinhloko wokukhishwa kwe-dioxin ukushiswa kwemfucuza equkethe i-chlorine. Ukuze ugweme ukukhululwa kwalezi zinhlanganisela eziyingozi, ukufakwa okufakwe okuthiwa. afterburner, at min. 1200°C.

Udoti ugaywa kabusha ngezindlela ezahlukene

Ubuchwepheshe ukugaywa kabusha kwemfucuza eyenziwe ngepulasitiki ukulandelana kwezigaba eziningi. Ake siqale ngeqoqo elifanele le-sediment, okungukuthi, ukuhlukaniswa kwepulasitiki kusuka kudoti. Embonini yokucubungula, ukuhlunga kuqala kuqala, bese kugaywa futhi kugaywe, ukuhlukaniswa kwemizimba yangaphandle, bese kuhlungwa amapulasitiki ngohlobo, ukoma nokuthola umkhiqizo osuphelile kusukela ezintweni zokusetshenziswa ezitholiwe.

Akwenzeki ngaso sonke isikhathi ukuhlunga udoti oqoqwe ngohlobo. Yingakho zihlungwa ngezindlela eziningi ezahlukene, ngokuvamile zihlukaniswa zibe yimishini namakhemikhali. Izindlela zemishini zihlanganisa: ukuhlukaniswa ngesandla, i-flotation noma i-pneumatic. Uma imfucuza ingcolile, ukuhlunga okunjalo kwenziwa ngendlela emanzi. Izindlela zamakhemikhali zihlanganisa i-hydrolysis - ukubola kwe-steam yama-polymers (izinto zokusetshenziswa zokukhiqiza kabusha ama-polyester, ama-polyamides, ama-polyurethanes nama-polycarbonates) noma izinga lokushisa eliphansi le-pyrolysis, okuthi, ngokwesibonelo, amabhodlela e-PET namathayi asetshenzisiwe alahlwe.

Ngaphansi kwe-pyrolysis qonda ukuguqulwa okushisayo kwezinto eziphilayo endaweni ene-anoxic ngokuphelele noma engenawo umoya-mpilo omncane noma ongenawo nhlobo. I-pyrolysis yezinga lokushisa eliphansi iqhubeka ekushiseni kuka-450-700 ° C futhi iholela ekwakhekeni, phakathi kwezinye izinto, igesi ye-pyrolysis, ehlanganisa umhwamuko wamanzi, i-hydrogen, i-methane, i-ethane, i-carbon monoxide ne-carbon dioxide, kanye ne-hydrogen sulfide kanye ammonia, uwoyela, itiyela, amanzi kanye ne-organic matter, i-pyrolysis coke nothuli olunokuqukethwe okuphezulu kwezinsimbi ezisindayo. Ukufakwa akudingi ukunikezwa kwamandla, njengoba kusebenza kugesi ye-pyrolysis ekhiqizwa ngesikhathi senqubo yokubuyisela kabusha.

Kuze kufike ku-15% wegesi ye-pyrolysis isetshenziselwa ukusebenza kokufakwa. Inqubo iphinde ikhiqize kuze kufike ku-30% we-pyrolysis liquid, efana nowoyela uphethiloli, ongahlukaniswa ngezingxenyana ezifana nalezi: 30% uphethiloli, i-solvent, 50% uwoyela kawoyela kanye no-20% uwoyela uphethiloli.

Ezinye izinto ezingavuthiwe zesibili ezitholwe ethanini elilodwa lemfucuza yilezi: kuze kufike ku-50% i-carbon pyrocarbonate imfucumfucu eqinile, ngokwenani le-calorific eduze ne-coke, engasetshenziswa njengophethiloli oqinile, ikhabhoni ecushiwe yezihlungi noma impushana i-pigment yamapende kanye nensimbi efika ku-5% (i-stern scrap) ngesikhathi sokwenziwa kwe-pyrolysis yamathayi emoto.

Izindlu, imigwaqo kanye nophethiloli

Izindlela zokugaywa kabusha ezichazwe yizinqubo ezibucayi zezimboni. Azitholakali kuzo zonke izimo. Isitshudeni sobunjiniyela saseDenmark uLisa Fuglsang Vestergaard (9) uqhamuke necebo elingajwayelekile ngesikhathi ehlala edolobheni laseNdiya iJoygopalpur eNtshonalanga Bengal - kungani kungenziwa izitini abantu abangazisebenzisa ukwakha izindlu ngezikhwama ezihlakazekile namaphasela?

9. ULisa Fuglsang Westergaard

Akukhona nje ukwenza izitini, kodwa ukuklama yonke inqubo ukuze abantu abahilelekile kulo msebenzi bazuze ngempela. Ngokohlelo lwakhe, imfucuza iqala ukuqoqwa futhi, uma kunesidingo, iyahlanzwa. Izinto eziqoqiwe zibe sezilungiswa ngokusikwa zibe izingcezu ezincane ngesikelo noma imimese. Impahla eluhlaza echotshoziwe ifakwa esikhunjeni futhi ibekwe ku-grate yelanga lapho ipulasitiki ishiswa khona. Ngemva kwehora, ipulasitiki izoncibilika, futhi ngemva kokupholisa, ungasusa isitini esiqediwe esikhunjeni.

izitini zepulasitiki banezimbobo ezimbili lapho izinti ze-bamboo zingafakwa khona, zidale izindonga ezizinzile ngaphandle kokusebenzisa usimende noma ezinye izibopho. Khona-ke izindonga zepulasitiki ezinjalo zingafakwa ngendlela yendabuko, isibonelo, ngongqimba lobumba oluzivikela elangeni. Izindlu ezenziwe ngezitini zepulasitiki nazo zinenzuzo yokuthi, ngokungafani nezitini zobumba, ziyamelana, isibonelo, izimvula ze-monsoon, okusho ukuthi ziba namandla kakhulu.

Kuhle ukukhumbula ukuthi imfucuza yepulasitiki isetshenziswa naseNdiya. ukwakhiwa komgwaqo. Bonke abathuthukisi bemigwaqo ezweni kudingeka ukuthi basebenzise imfucuza yepulasitiki kanye nezingxube zebituminous ngokuhambisana nomthetho kahulumeni wase-India wangoNovemba 2015. Lokhu kufanele kusize ukuxazulula inkinga ekhulayo yokugaywa kabusha kwepulasitiki. Lobu buchwepheshe basungulwa nguProf. U-Rajagopalan Vasudevan waseMadurai School of Engineering.

Yonke inqubo ilula kakhulu. Imfucuza iqala ukuchotshozwa ibe yisayizi ethile kusetshenziswa umshini okhethekile. Bese zengezwa ku-aggregate elungiselelwe kahle. Udoti ogcwaliswe ngemuva uhlanganiswe netiyela elishisayo. Umgwaqo ubekwe ezingeni lokushisa elingu-110 kuya ku-120°C.

Ziningi izinzuzo zokusebenzisa imfucuza yepulasitiki ekwakhiweni komgwaqo. Inqubo ilula futhi ayidingi imishini emisha. Kuwo wonke amakhilogremu etshe, kusetshenziswa amagremu angama-50 wetiyela. Ingxenye yeshumi yalokhu ingaba imfucuza yepulasitiki, enciphisa inani letiyela elisetshenziswayo. Imfucumfucu yepulasitiki ibuye ithuthukise izinga eliphezulu.

UMartin Olazar, unjiniyela eNyuvesi Yezwe Lase-Basque, wakhe ulayini wenqubo othokozisayo futhi othembisayo wokucubungula imfucuza kumafutha e-hydrocarbon. Isitshalo, umsunguli asichaza ngokuthi indawo yokucwenga imayini, isekelwe ku-pyrolysis ye-biofuel feedstocks ukuze isetshenziswe ezinjini.

U-Olazar wakhe izinhlobo ezimbili zemigqa yokukhiqiza. Eyokuqala icubungula i-biomass. Okwesibili, okuthakazelisayo nakakhulu, kusetshenziselwa ukuvuselela imfucuza yepulasitiki ibe yizinto ezingasetshenziswa, isibonelo, ekukhiqizeni amathayi. Imfucuza ingaphansi kwenqubo ye-pyrolysis esheshayo ku-reactor ezingeni lokushisa eliphansi kakhulu lika-500 ° C, elinomthelela ekongeni amandla.

Naphezu kwemibono emisha nentuthuko kwezobuchwepheshe bokugaywa kabusha, amaphesenti amancane kuphela amathani ayizigidi ezingu-300 emfucumfucu yepulasitiki ekhiqizwa emhlabeni wonke unyaka ngamunye embozwa yikho.

Ngokocwaningo olwenziwa yi-Ellen MacArthur Foundation, u-15% kuphela wamaphakethe othunyelwa kuma-container futhi u-5% kuphela osetshenziswa kabusha. Cishe ingxenye yesithathu yamapulasitiki angcolisa imvelo, lapho ezohlala khona amashumi eminyaka, ngezinye izikhathi amakhulu eminyaka.

Udoti mazincibilike

Ukugaywa kabusha kukadoti wepulasitiki kungenye yezinkomba. Kubalulekile, ngoba sesivele sikhiqize kadoti omningi, futhi ingxenye enkulu yemboni isahlinzeka ngemikhiqizo eminingi evela kumapulasitiki amakhulu amahlanu amathani amaningi. Nokho ngokuhamba kwesikhathi, ukubaluleka kwezomnotho kwamapulasitiki angaboli, izinto ezintsha zesizukulwane esekwe, ngokwesibonelo, kokuphuma kwesitashi, i-polylactic acid noma ... usilika, kungenzeka kwande..

10. I-d2w izikhwama zikadoti wezinja ezingaboli.

Ukukhiqizwa kwalezi zinto kusabiza kakhulu, njengoba kuvame ukuba njalo ngezixazululo ezintsha. Kodwa-ke, wonke umthethosivivinywa awunakuzitshwa njengoba ukhipha izindleko ezihambisana nokugaywa kabusha nokuchithwa.

Omunye wemibono ethakazelisa kakhulu emkhakheni wepulasitiki e-biodegradable yenziwe nge-polyethylene, i-polypropylene ne-polystyrene, kubonakala sengathi ubuchwepheshe obusekelwe ekusetshenzisweni kwezinhlobo ezahlukene zezithasiselo ekukhiqizeni kwazo, ezaziwa yizivumelwano. d2w (10) noma FUTHI.

Okwaziwa kangcono, okuhlanganisa nasePoland, iminyaka eminingana manje umkhiqizo we-d2w wenkampani yaseBrithani i-Symphony Environmental. Kuyisithasiselo sokukhiqizwa kwamapulasitiki athambile futhi aqinile, lapho sidinga khona ukuzilimaza okusheshayo, okunobungani kwemvelo. Ngokomsebenzi, ukusebenza kwe-d2w kubizwa i-oxybiodegradation yamapulasitiki. Le nqubo ihilela ukubola kwezinto zibe amanzi, i-carbon dioxide, i-biomass kanye ne-trace elements ngaphandle kwezinye izinsalela futhi ngaphandle kokukhipha i-methane.

Igama elijwayelekile elithi d2w lisho uhla lwamakhemikhali engezwe ngesikhathi sokukhiqiza njengezithasiselo ku-polyethylene, i-polypropylene ne-polystyrene. Okubizwa nge-d2w prodegradant, esekela futhi esheshisa inqubo yemvelo yokubola ngenxa yethonya lanoma yiziphi izici ezikhethiwe ezikhuthaza ukubola, njengezinga lokushisa, ukukhanya kwelanga, ingcindezi, ukulimala komshini noma ukwelula okulula.

Ukuwohloka kwamakhemikhali e-polyethylene, okuhlanganisa ama-athomu e-carbon ne-hydrogen, kwenzeka lapho ibhondi ye-carbon-carbon iphulwa, yona-ke, inciphisa isisindo samangqamuzana futhi iholele ekulahlekelweni kwamandla eketango nokuqina. Ngenxa ye-d2w, inqubo yokuwohloka kwempahla yehlisiwe yaba yizinsuku ezingamashumi ayisithupha. Isikhathi sekhefu - okubalulekile, isibonelo, kubuchwepheshe bokupakisha - kungahlelwa ngesikhathi sokukhiqizwa kwezinto ngokulawula ngokufanele okuqukethwe kanye nezinhlobo zezithasiselo. Uma sekuqaliwe, inqubo yokuwohloka izoqhubeka kuze kube yilapho umkhiqizo usucekeleke phansi, noma ngabe ujulile ngaphansi komhlaba, ungaphansi kwamanzi noma ungaphandle.

Ucwaningo lwenziwe ukuze kuqinisekiswe ukuthi ukuzihlukanisa kusuka ku-d2w kuphephile. Ipulasitiki equkethe i-d2w isihloliwe kakade kumalabhorethri aseYurophu. Ilabhorethri yakwaSmithers/RAPRA ihlole ukufaneleka kwe-d2w ukuthintana nokudla futhi ibisetshenziswa abathengisi bokudla abakhulu eNgilandi iminyaka embalwa. Isengezo asinawo umthelela onobuthi futhi siphephile emhlabathini.

Yebo, izixazululo ezifana ne-d2w ngeke zisheshe zithathele indawo yokugaywa kabusha okuchazwe ngaphambilini, kodwa zingangena kancane kancane ohlelweni lokugaywa kabusha. Ekugcineni, i-prodegradant ingangezwa ezintweni ezingavuthiwe ezivela kulezi zinqubo, futhi sithola i-oxybiodegradable material.

Isinyathelo esilandelayo amapulasitiki, abola ngaphandle kwezinqubo zezimboni. Okunjalo, ngokwesibonelo, njengalezo ezenziwe ngamasekethe e-elekthronikhi ama-ultra-thin, ancibilika ngemuva kokwenza umsebenzi wawo emzimbeni womuntu., eyethulwa okokuqala ngo-Okthoba nyakenye.

Ukusungulwa ukuncibilika kwamasekethe kagesi kuyingxenye yocwaningo olukhudlwana lwalokho okubizwa ngokuthi okwedlula ngokushesha - noma, uma uthanda, "isikhashana" - i-electronics () nezinto ezizonyamalala ngemva kokuqeda umsebenzi wazo. Ososayensi sebevele benze indlela yokwakha ama-chips kusuka ezingqimbeni ezincanyana kakhulu, ezibizwa i-nanomembrane. Zincibilika phakathi kwezinsuku noma amasonto ambalwa. Ubude besikhathi sale nqubo bunqunywa izici zongqimba lukasilika oluhlanganisa izinhlelo. Abacwaningi banamandla okulawula lezi zakhiwo, okungukuthi, ngokukhetha imingcele yesendlalelo esifanele, banquma ukuthi kuzohlala isikhathi esingakanani ukuvikela unomphela ohlelweni.

Njengoba kuchazwe yi-BBC Prof. U-Fiorenzo Omenetto wase-Tufts University e-US: “Izinto zikagesi ezincibilikayo zisebenza ngokwethembeka njengamasekhethi avamile, zincibilika ziye lapho ziya khona endaweni ezikuyo, ngesikhathi esishiwo umklami. Kungaba izinsuku noma iminyaka. "

Ngokusho kukaProf. John Rogers waseNyuvesi yase-Illinois, ukuthola amathuba kanye nokusetshenziswa kwezinto ezilawulwayo zokuhlakazeka kuseza. Mhlawumbe amathemba athakazelisa kakhulu alokhu okusunguliwe emkhakheni wokulahlwa kwemfucuza yemvelo.

Ingabe amagciwane azosiza?

Amapulasitiki ancibilikayo angenye yezitayela zesikhathi esizayo, okusho ukushintshela ezintweni ezintsha ngokuphelele. Okwesibili, bheka izindlela zokubola ngokushesha izinto ezilimaza imvelo esezivele zisendaweni ezungezile futhi kungaba kuhle uma zinyamalala lapho.

Muva nje I-Kyoto Institute of Technology yahlaziya ukucekelwa phansi kwamabhodlela epulasitiki angamakhulu amaningana. Ngesikhathi socwaningo, kwatholakala ukuthi kunegciwane elikwazi ukubola amapulasitiki. Bambize . Ukutholwa kwachazwa ephephabhukwini elihlonishwayo iSayensi.

Le ndalo isebenzisa ama-enzyme amabili ukususa i-PET polymer. Enye iqala ukusabela kwamakhemikhali ukuze iphule ama-molecule, enye isiza ukukhulula amandla. Ibhaktheriya litholakale kwelinye lamasampula angu-250 athathwe eduze kwesikhungo sokugaywa kabusha kwebhodlela le-PET. Yayifakwe eqenjini lama-microorganisms abola ingaphezulu le-PET membrane ngesilinganiso esingu-130 mg/cm² ngosuku ku-30°C. Ososayensi baphinde bakwazi ukuthola isethi efanayo yama-microorganisms angenawo, kodwa angakwazi ukugaya i-PET. Lezi zifundo zibonise ukuthi ngempela yenza ipulasitiki ye-biodegrade.

Ukuze kutholwe amandla ku-PET, ibhaktheriya iqala i-hydrolyze i-PET nge-enzyme yesiNgisi (PET hydrolase) ibe yi-mono(2-hydroxyethyl) terephthalic acid (MGET), ebese i-hydrolyzed esinyathelweni esilandelayo kusetshenziswa i-enzyme yesiNgisi (MGET hydrolase) . kuma-monomers epulasitiki okuqala: i-ethylene glycol ne-terephthalic acid. Amagciwane angasebenzisa la makhemikhali ngokuqondile ukuze akhiqize amandla (11).

11. Ukucekelwa phansi kwe-PET ngamagciwane 

Ngeshwa, kuthatha amasonto ayisithupha agcwele kanye nezimo ezifanele (kuhlanganise nezinga lokushisa elingu-30°C) ukuze ikoloni lonke lembule ucezu oluncane lwepulasitiki. Akulishintshi iqiniso lokuthi okutholakele kungashintsha ubuso bokusebenzisa kabusha.

Ngeke nakanjani siphile nodoti wepulasitiki ohlakazeke yonke indawo (12). Njengoba okutholwe kwakamuva emkhakheni wesayensi yezinto ezibonakalayo kubonisa, singasusa ipulasitiki enkulu futhi okunzima ukuyikhipha unomphela. Nokho, ngisho noma maduze nje sishintshela kupulasitiki obolayo ngokuphelele, thina nezingane zethu kuzodingeka sibhekane nezinsalela isikhathi eside esizayo. inkathi yepulasitiki elahliwe. Mhlawumbe lokhu kuzoba isifundo esihle esintwini, esingasoze sayeka ubuchwepheshe ngaphandle komcabango wesibili ngoba ishibhile futhi kulula?