Te Tukatuka i ngā Para Waro ki te Biogas
Ko te para rauropi te momo para e tino kitea ana e puta mai ana i ngā mahi o ia rā, inā koa mai i ngā whare, ngā mākete, ngā wharekai, me te umanga tukatuka kai. Kei roto i tēnei kāwai ngā toenga huawhenua, ngā kiri hua, te raihi, ngā paura kawhe, ngā toenga rihi taha, ngā rau maroke, me te paru kararehe. I te nuinga o ngā wāhi, ka mutu tonu ngā para rauropi ki ngā whenua ururua (TPA) me te kore e tika te tukatuka. Nō reira, ka puta ngā haunga kino mai i ngā puranga para, ka kukume i ngā pepeke, ka whakapoke i te wai rere, ka tukuna te hau methane (CH₄) ki te āhuarangi me te kore e taea te whakahaere. Heoi, he puna pūngao nui te methane ina whakahaerea tika. Koinei te wāhi e whakarato ai te biogas i tētahi otinga: te huri i te taumahatanga taiao hei puna pūngao hou.
He aha te Biogas?
Ko te hau koiora he hau e puta mai ana i te pirau o ngā mea rauropi e ngā moroiti i te korenga o te hāora (anaerobic). Ko te hau koiora he mea hanga i te methane (tata ki te 50–70%), te hauhā waro (CO₂) (30–50%), me ētahi atu hau iti pēnei i te hauwai whanariki (H₂S), te mamaoa wai, me te hauota. Ko te methane te wāhanga matua e mura ana, e āhei ai te whakamahi i te hau koiora mō te tunu kai, te whakamahana wai, te whakamārama, tae noa ki te wahie whakaputa hiko. Mā te tukatuka anō (whakapai ake), ka taea hoki te whakamahine i te hau koiora hei methane, he rite te kounga ki te hau māori.
He aha i pai ai te tukatuka i ngā para rauropi hei hau koiora?
Kei roto i ngā para rauropi ngā warowaihā, ngā pūmua, me ngā ngako e ngāwari ana te pirau e ngā moroiti. He "kai" ēnei rauemi mā ngā huakita e whakaputa ana i te hau koiora. Ki te whakaritea ki te tāpui noa i ngā whenua, he maha ngā painga o te tukatuka anaerobic: ka whakaitihia te nui o ngā para, ka āraihia ngā tukunga methane ture kore, ka puta te pūngao hou, ā, ka taea te whakamahi i te otaota hei tongi rauropi. Ko te tikanga o tēnei, ka tautoko te hau koiora i te ōhanga porowhita mā te whakahoki i ngā matūkai ki te whenua ahuwhenua.
Te Mahi a te Pūwero Hauota
Ko te tukatuka i ngā para rauropi hei hau koiora ka mahia i roto i tētahi tauhohenga kati e kiia nei ko te digester. I roto i te digester, ka mahi ngā moroiti i roto i ētahi wāhanga:
1. Te Waikawa: Ka wahia ngā ngota nui pēnei i te māngaro, te cellulose, ngā pūmua, me ngā ngako ki ngā matū māmā ake (huka, waikawa amino, waikawa ngako).
2. Te Waikawa: Ka hurihia ngā matū māmā hei waikawa waro, hei waipiro, hei CO₂, me te hauwai.
3. Te Acetogenesis: Ka hurihia ngā hua o te wāhanga o mua hei waikawa acetic, CO₂, me te hauwai.
4. Methanogenesis: Ka hurihia e ngā huakita methanogenesis te waikawa acetic me te hauwai me te CO₂ hei methane (CH₄).
Me taurite te tūnga o ēnei wāhanga e whā. Mēnā ka whakararuraruhia tētahi wāhanga—hei tauira, mēnā ka nui rawa te waikawa—ka heke te hanga hau koiora.
Ngā Rauemi Mata me te Whakarite Para
Kāore i te ōrite te hanganga o ngā para rauropi katoa. Ko ngā para kīhini he mākū, he ngāwari hoki te pirau, ko ngā rau maroke ia he muka ake, ā, he roa ake te tukanga. Mō ngā hua tino pai, me wehe te para mai i ngā rauemi kore-rauropi pērā i te kirihou, te konganuku, me te karāhe. Hei tāpiri, ka taea te tapatapahi i ngā rauemi rauropi kia iti ake, kia tere ake ai te pirau.
I roto i te mahi, ka konatunatuahia ngā para rauropi ki te wai hei hanga i te paru hei whakahaere i te papu me te whakaranu i roto i te mīhini keri. Ka tāpirihia hoki e ētahi pūnaha he tīmatanga i roto i te ahua o te paru mai i te mīhini keri hohe, i te paru kararehe rānei, nā te mea kei roto i ēnei he taupori huakita anaerobic e āwhina ana ki te whakatau tere i te tukanga.
Ngā momo mīhini keri hau koiora
He maha ngā momo mīhini keri e whakamahia whānuitia ana:
– He pūmau te kōhatu: He mīhini keri kōhatu raima tuturu. He nui te utu i te tīmatanga, engari he pakari, ā, he iti noa te tiaki e hiahiatia ana.
– Pahu mānu: He pahu rokiroki hau mānu, kia mau ai te pēhanga hau. Heoi, he ngawari te waikura o ngā wāhanga whakarewa.
– Pūwero keri pēke (kirihou/geomembrane): He iti ake te utu, he māmā ake hoki te tāuta, he pai mō te whakamahinga iti, mō te hapori rānei. He poto ake te roa o te ora i te raima.
– Ngā mīhini keri para ā-ahumahi (CSTR, plug flow, UASB): Whakamahia mō ngā rahinga nui pēnei i te para mākete, ngā wheketere kai, ngā kararehe rānei.
Ko te kōwhiringa o te mīhini keri ka whakatauhia e te tauine, te momo rauemi mata, te waatea o te moni, me ngā hiahia pūngao.
Ngā Āhuatanga Pai mō te Whakaputa Hau Koiora
Kia pai ai te mahi a ngā moroiti, me pupuri tonu ētahi āhuatanga:
– Pāmahana: E rua ngā awhe whānui: te pāmahana-kore (tata ki te 30–40°C) me te pāmahana-kore (50–60°C). He pumau ake te pāmahana-kore mō te whakamahinga o te whare.
– pH: Ko te mea pai ko te 6,8–7,5. Mēnā he waikawa rawa, ka pāngia ngā methanogens.
– Te ōwehenga C/N: Ko te ōwehenga waro ki te hauota tino pai ko te 20–30:1. I ētahi wā, he nui rawa te hauota i roto i ngā para kīhini; ka taea tēnei te whakataurite ki ngā rauemi whai waro pērā i ngā rau maroke.
– Te wā noho (HRT): Ko te roa o te wā e noho ai te rauemi i roto i te mīhini keri, ko te tikanga he 20–40 rā i runga i te momo rauemi me te pāmahana.
– Te whakaoho: Ka āwhina i te horapa o ngā moroiti me te ārai i te whakatōpuku, engari kaua e nui rawa nā te mea ka taea te whakararuraru i ngā koroni.
Te Whakamahinga o te Biogas me te Digestate
Ka tukuna te hau koiora e puta mai ana ki te oumu hau koiora, ki tētahi atu taputapu rānei. Nā te mea kei roto i te hau koiora te H₂S me te mamaoa wai, ka tāpirihia e ētahi pūnaha he tātari māmā pēnei i ngā ipu rino/waro whakahohe, he mahanga waikura rānei hei whakaiti i te waikura me te haunga kino.
Ko te toenga totoka/wai mai i te mīhini keri ka kiia ko te keri. He nui ngā matūkai kei roto i te keri pērā i te hauota, te whākawa, me te pāhare pākawa, tae atu ki ngā mea rauropi he pai mō te whakapai ake i te hanganga o te oneone. Ka taea te whakamahi i te keri hei tongi wai, hei wairākau, hei ranunga rānei mō te whakatipu i muri i te tukanga pakari. Mā tēnei, kāore te hua taha e waiho hei para hou, engari hei puna matūkai mō ngā tipu.
Ngā Painga Taiao me te Hapori
He tino painga te tukatuka i ngā para rauropi hei hau koiora:
1. Whakaitihia te nui o ngā para e tukuna ana ki te whenua ururua, kia roa ake ai te ora o te whenua ururua, kia iti ake ai hoki ngā utu kawe.
2. Ka whakaiti i ngā tukunga hau kati kōtuhi nā te mea ka hopukina, ka whakamahia hoki te methane, kāore e tukuna noa.
3. Whakaputa pūngao ma e taea ai te whakakapi i te LPG, te wahie, te hinu rānei.
4. Whakaitihia te parahanga me ngā haunga kino o te taiao, inā koa i ngā wāhi me ngā mākete e kī ana te taupori.
5. Te waihanga i ngā whai wāhitanga ōhanga mā te whakahaere para ā-hapori, te whakaputa tongi waro, me te penapena utu pūngao.
I te taumata kāinga, i te taumata hapori rānei, he maha ngā wā ka whakamahia te hau koiora hei whakakaha i te mana motuhake o te pūngao. I ngā tāone nui, ka taea te whakamahi i ngā pūnaha hau koiora i roto i ngā mākete tuku iho me ngā wharekai hei tukatuka i te nui o ngā para kai.
Ngā Wero i roto i te Whakatinanatanga
Ahakoa tōna pūmanawa, he maha ngā wero e pā ana ki te whakatinanatanga o te hau koiora. Tuatahi, he maha ngā wā kāore i te ōrite te wehewehenga o ngā para; ka taea e te noho mai o ngā rauemi kirihou me ngā rauemi kore-ora te aukati i te pūnaha. Tuarua, ka taea e ngā panonitanga o te hanganga o ngā rauemi mata te whakararuraru i te tukanga, hei tauira, ka taea e te nui rawa o te hinu/hinu te whakaheke i te mahi a te mīhini keri. Tuatoru, me whai mātauranga hangarau taketake hei pupuri i te pH, hei whakahaere i ngā whakaurunga o ia rā, me te tiaki i ngā paipa me ngā puna hau. Hei tāpiri, he nui rawa te haumitanga tuatahi ki te hanga i tētahi mīhini keri, ahakoa ka taea te utu i roto i te wā roa mā te penapena pūngao.
Rautaki Whakawhanake Whai Hua
Hei whakarite kia angitu te tukatuka i ngā para rauropi hei hau koiora, he maha ngā rautaki ka taea te whakatinana: te mātauranga mō te wehewehe para i te pūtake, te hoahoa o te mīhini keri para e hāngai ana ki ngā hiahia o te rohe, te whakangungu kaiwhakahaere, me te tautoko kaupapa here pēnei i ngā whakatenatena pūngao hou. He mea nui hoki te mahi tahi i waenga i te kāwanatanga, ngā hapori, me te rāngai tūmataiti, inā koa mō ngā pakihi tauine waenga pēnei i ngā mākete me ngā pokapū tunu kai. Mēnā he mekameka whakahaere kua whakaritea pai - mai i te kohikohi me te tukatuka rauemi rauropi ki te whakamahinga o te keri para - ka taea e te hau koiora te noho hei wāhanga nui o te pūnaha whakahaere para hou.
Te Katinga
Ko te tukatuka i ngā para rauropi hei hau koiora he otinga e whakakotahi ana i te whakaiti i ngā para, te whakaputa pūngao hou, me te whakamahi anō i ngā matūkai mā te tongi rauropi. Ka mahi tēnei hangarau i runga i te kaupapa o te whakapūtanga anaerobic i roto i te mīhini keri, ka puta he hau methane ka taea te whakamahi mō ngā hiahia pūngao o ia rā. Mā te whakahaere tika—te wehewehe para, te whakahaere i ngā āhuatanga o te mīhini keri, me te whakamahi i ngā hua taha—ka taea e te hau koiora te āwhina i te whakatika i ngā take para me te whakapakari ake i te haumarutanga pūngao. I waenganui i ngā wero taiao me te piki haere o ngā hiahia pūngao, ka tukuna e te hau koiora he ara whai hua ki tētahi heke mai ma ake, pumau ake hoki.
