Tam sim no, EU cov cai tswjfwm ib puag ncig feem ntau tsom rau kev siv cov yas rov ua dua tshiab, nrog rau kev ua lag luam saib xyuas qhov tseem ceeb ntawm cov khoom siv rov ua dua tshiab, bio- cov ntaub ntawv raws li, thiab cov ntaub ntawv biodegradable thaum kawg. Bio-raws li plastics xa mus rau cov yas tau los ntawm biomass, xws li PLA (polylactic acid) thiab Bio-PE; thaum biodegradable plastics hais txog cov yas uas tuaj yeem tawg los ntawm cov kab mob, suav nrog PLA thiab PHA. Ob leeg tsis yog kev sib koom ua ke.
Taw qhia rau Bio-raws li thiab Biodegradable Plastics
Los ntawm EU txoj kev xav tam sim no ntawm kev lag luam ncig ntawm cov yas, EU cov cai tsis ntev los no tau txhawb nqa kev siv cov yas rov ua dua tshiab kom ntev lawv lub neej. Los ntawm kev xav ntawm kev ua lag luam, qhov kev txiav txim ntawm qhov tseem ceeb rau kev siv cov yas zoo ib puag ncig hauv European thiab Asmeskas kev lag luam yog:
1. Cov khoom siv rov ua dua tshiab
2. Bio-raws li cov ntaub ntawv
3. Cov ntaub ntawv biodegradable - nrog rau tshwj xeeb ntawm marine degradation ntawm biodegradable cov ntaub ntawv.
Raws li EU Environment Agency lub ntsiab lus:
(1) Bio-raws li plastics hais txog cov yas uas siv (ib feem) biomass, xws li qab zib, hmoov txhuv nplej siab, lossis cov khoom siv cog, tsis yog roj av.
(2) Biodegradable plastics xa mus rau cov yas uas tuaj yeem ua rau decomposed los ntawm cov kab mob nyob rau hauv tej yam kev mob, txawm hais tias cov xwm txheej thiab lub sij hawm yuav tsum tau rau decomposition txawv.
Cov kev faib tawm no tsis yog kev sib koom ua ke. Cov yas ua los ntawm biomass tsis tau lees tias yuav biodegradable; biodegradable plastics tuaj yeem siv roj av los ua cov khoom siv raw.
Ntxiv rau qhov saum toj no, muaj ntau ntau yam xws li industrially compostable plastics, tsev compostable plastics, thiab oxidatively degradable plastics.
Bio-raws li tsis yog- biodegradable plastics xa mus rau ib chav kawm ntawm cov yas uas nws cov ntaub ntawv raw yog ib feem lossis tag nrho los ntawm biomass. Txawm hais tias cov yas no yog tsim los ntawm cov khoom siv txuas ntxiv dua tshiab, lawv tsis tas yuav biodegradable. Seb ib yam dab tsi yog biodegradable nyob ntawm cov qauv tshuaj ntawm nws cov molecules, tsis nyob ntawm seb nws tau ua li cas.
Piv txwv li:
Bio-raws li plastics: Cov yas no yog tsim los ntawm cov khoom siv txuas ntxiv dua tshiab, xws li pob kws, qab zib, cellulose, ntses tawv nqaij, thiab cov noob paj noob hlis. Txawm li cas los xij, txawm tias 100% bio-raws li plastics tsis tas yuav biodegradable. Piv txwv li, PET (polyethylene terephthalate) tuaj yeem ua rau biosynthesized tab sis tsis biodegradable, thaum PLA (polylactic acid) tuaj yeem yog biosynthesized thiab biodegradable. Yog li ntawd, bio-raws li plastics feem ntau hais txog qhov teeb meem ntawm cov khoom siv raw.
Biodegradable plastics: Cov yas no tuaj yeem decompose ib txwm nyob rau hauv kev ua ntawm cov kab mob. Biodegradation yog cov txheej txheem tshuaj uas cov kab mob nyob hauv ib puag ncig hloov cov tshuaj mus rau hauv cov ntaub ntawv ntuj xws li dej, carbon dioxide, thiab cov khoom siv compostable yam tsis muaj cov khoom siv dag zog. Cov txheej txheem biodegradation feem ntau yog txiav txim siab los ntawm ib puag ncig (xws li kub lossis qhov chaw), cov khoom siv, thiab kev siv. PLA, PHA, thiab PBS yog tag nrho cov yas biodegradable. Cov plastics no pab tswj cov khoom pov tseg thiab txo "dawb paug" thaum kawg ntawm lawv cov khoom lifespan.
Bio-raws li Plastics
Bio-raws li plastics yog cov yas tsim ib feem lossis tag nrho los ntawm cov khoom siv roj ntsha txuas ntxiv (xws li cov nroj tsuag thiab cov kab mob) es tsis yog fossil fuels (xws li roj av). Cov yas no siv cov khoom siv roj ntsha xws li pob kws qab zib, qab zib, cov roj zaub, thiab cellulose ua cov khoom siv raw, uas tau hloov mus rau hauv cov yas los ntawm cov txheej txheem tshuaj lom neeg lossis cov txheej txheem lom neeg. Muaj ntau hom bio-raws li plastics, suav nrog tab sis tsis txwv rau cov hauv qab no:
1. Polylactic acid (PLA): Ib qho ntawm feem ntau bio-raws li plastics, nws yog polymerized los ntawm lactic acid uas ua los ntawm fermentation ntawm pob kws qab zib los yog lwm yam nroj tsuag qab zib. PLA yog dav siv nyob rau hauv ntim, pov tseg tableware, textiles, thiab lwm yam.
2. Bio-raws li polyethylene (Bio-PE): Nws siv ethanol rho tawm los ntawm cov qoob loo xws li qab zib los ua raw khoom, uas yog dehydrated los tsim ethylene thiab ces polymerized.
3. Bio-raws li polyethylene (Bio-PET) muaj cov qauv tshuaj tib yam li cov tshuaj polyethylene, tab sis nws cov ntaub ntawv raw yog muab los ntawm cov khoom siv txuas ntxiv.
4. Bio-raws li polyethylene terephthalate (Bio-PET) yog tsim los siv bio-raws li raw cov ntaub ntawv (xws li ethanol muab tau los ntawm qab zib) es tsis txhob fossil fuels. Cov ntawv thov suav nrog kev tsim cov fwj yas thiab cov khoom ntim khoom.
5. Bio-raws li polypropylene (Bio-PP) zoo ib yam li Bio-PE thiab Bio-PET, tab sis siv cov khoom siv txuas ntxiv ua cov khoom siv raw. Nws yog siv nyob rau hauv ntim, automotive qhov chaw, thiab ntau yam kev siv.
6. Polyhydroxyalkanoates (PHAs) yog ib hom biodegradable yas uas tsim ncaj qha los ntawm cov kab mob los ntawm cov txheej txheem fermentation. PHA yog biodegradable kiag li thiab haum rau ntim, ua liaj ua teb zaj duab xis, thiab biomedical cov ntaub ntawv.
7. Bio-raws li nylon (Bio-Nylon) yog tsim los siv bio-raws li raw cov ntaub ntawv (xws li roj castor) es tsis txhob ntawm ib co petrochemical raw khoom. Nws yog siv hauv textiles thiab engineering plastics. Cov bio-raws li cov yas no muab cov txiaj ntsig zoo ib puag ncig xws li txo kev cia siab ntawm fossil fuels thiab txo qis cov pa hluav taws xob hauv tsev, tab sis lawv cov khoom tsim thiab kev siv tseem xav tau kev xav txog yam xws li kev muaj peev xwm ntawm cov khoom siv raw thiab lawv cov kev cuam tshuam ib puag ncig thoob plaws hauv lawv lub neej. Nrog rau kev txhim kho thev naus laus zis thiab kev xav tau ntawm kev lag luam, ntau hom bio-raws li plastics tau tsim thiab ua lag luam.
Biodegradable Plastics
Biodegradable plastics yog cov yas uas tuaj yeem tawg rau hauv dej, carbon dioxide lossis methane, thiab biomass los ntawm cov kab mob hauv cov xwm txheej, xws li kab mob, fungi, thiab algae, nyob rau hauv qee yam mob. Cov yas no tuaj yeem muab tau los ntawm cov khoom siv hluav taws xob txuas ntxiv (bio-raws li) lossis fossil fuels. Muaj ntau hom biodegradable plastics; qee qhov piv txwv zoo li no:
1. Polylactic acid (PLA) yog tsim los ntawm lactic acid uas ua los ntawm cov txheej txheem fermentation los ntawm cov khoom siv txuas ntxiv (xws li pob kws qab zib). PLA yog ib qho ntawm feem ntau siv biodegradable yas, haum rau ntim cov ntaub ntawv, pov tseg tableware, textiles, thiab lwm yam.
2. Polyhydroxyalkanoates (PHA) yog ib hom polyester ib txwm ua los ntawm cov kab mob hauv cov khoom noj tshwj xeeb. PHA yog biodegradable kiag li thiab tuaj yeem decompose nyob rau hauv ntau qhov chaw, suav nrog dej hiav txwv.
3. Polybutylene succinate (PBAT) yog cov khoom siv hluavtaws, tag nrho biodegradable yas feem ntau siv hauv kev tsim cov hnab khoom biodegradable thiab cov yeeb yaj kiab ua liaj ua teb. PBAT feem ntau sib xyaw nrog lwm cov khoom siv biodegradable xws li PLA lossis hmoov txhuv nplej siab los txhim kho nws cov khoom siv kho tshuab thiab tus nqi degradation.
4. Polycaprolactone (PCL) yog ib qho hluavtaws biodegradable polyester tau los ntawm lub nplhaib - qhib polymerization ntawm caprolactone monomers. PCL muaj tus nqi qis dua biodegradation, tab sis qhov no tuaj yeem txhim kho los ntawm kev sib xyaw nrog lwm cov ntaub ntawv biodegradable.
5. Starch-raws li plastics yog cov yas feem ntau ua los ntawm cov hmoov txhuv nplej siab, uas muaj ntau yam ntuj tsim. Starch-raws li plastics feem ntau yuav tsum tau muab sib xyaw nrog lwm cov biodegradable polymers (xws li PLA lossis PBAT) txhawm rau txhim kho lawv cov txheej txheem thiab lub cev.
6. Polyvinyl cawv (PVOH, PVA) yog dej- cov yas soluble uas degrades sai heev nyob rau hauv dej. PVOH feem ntau yog siv los ua dej - cov hnab ntim cov kua dej, xws li cov hnab ntxhua khaub ncaws.
Kev siv biodegradable plastics txo cov tsub zuj zuj ntawm cov tsoos plastics nyob rau hauv ib puag ncig, pab daws teeb meem cov pa phem. Txawm li cas los xij, lawv cov biodegradability nyob ntawm ib puag ncig ib puag ncig, xws li kub, av noo, thiab microbial kev ua haujlwm, yog li cov yam ntxwv no yuav tsum tau ua tib zoo xav txog hauv kev siv tswv yim. Tsis tas li ntawd, kev tsim thiab siv cov yas biodegradable yuav tsum xav txog lawv cov kev cuam tshuam ib puag ncig thoob plaws hauv lawv lub neej, suav nrog kev ruaj khov ntawm cov khoom siv raw, kev siv hluav taws xob thaum tsim khoom, thiab pov tseg cov khoom kawg.
