Test Drive Alternatives: CHIKAMU 1 - Gasi Indasitiri
Mumakore makumi manomwe, Wilhelm Maybach akayedza akasiyana magadzirirwo emota dzemukati dzemoto, akachinja mashandiro uye akafunga nezve maalloys akakodzera kugadzirwa kwezvimwe zvikamu. Anowanzo shamisika kuti ndechipi chezvinhu zvinozivikanwa zvinotsva chinogona kunge chakakodzera kushandiswa mumoto dzinopisa.
Mumakore makumi manomwe, Wilhelm Maybach akayedza akasiyana magadzirirwo emota dzemukati dzemoto, akachinja mashandiro uye akafunga nezve maalloys akakodzera kugadzirwa kwezvimwe zvikamu. Anowanzo shamisika kuti ndechipi chezvinhu zvinozivikanwa zvinotsva chinogona kunge chakakodzera kushandiswa mumoto dzinopisa.
Muna 1875, paakanga ari mushandi weGasmotorenfabrik Deutz, Wilhelm Maybach akasarudza kuedza kana aigona kushandisa injini yegesi pamafuta emvura - kunyanya, papeturu. Zvakauya kwaari kuti atarise kuti chii chaizoitika kana akavhara jongwe regesi uye panzvimbo pezvo akaisa chigamba chejira chakanyikwa mupeturu pamberi pechizhinji chekunwa. Injini haimire, asi inoramba ichishanda kusvikira "inosveta" mvura yose kubva munyama. Iyi ndiyo nzira iyo pfungwa yekutanga yakagadziridzwa "carburetor" yakazvarwa, uye mushure mekusikwa kwemotokari, peturu yakava mafuta makuru ayo.
Ndiri kutaura nyaya iyi kukuyeuchidza kuti peturu isati yaonekwa senge imwe peturu, mainjini ekutanga akashandisa gasi semafuta. Zvino zvaive pamusoro pekushandiswa kwe (kuvhenekera) gasi yemwenje, yakawanikwa nenzira dzisingazivikanwe nhasi, asi nekugadzirisa marasha. Injini, yakagadzirwa neSwitzerland Isaac de Rivac, yekutanga "yakasununguka aspirated" (isina kumanikidzwa) indasitiri giredhi Ethylene Lenoir injini kubvira 1862, uye yechinyakare-sitiroko unit yakagadzirwa naOtto chinguva chidiki, inomhanyisa gasi.
Pano zvakakosha kutaura musiyano pakati pegasi rechisikigo uye liquefied petroleum gas. Gasi rechisikigo rine 70 kusvika 98% methane, uye mamwe ari epamusoro organic uye inorganic magasi akadai seethane, propane uye butane, carbon monoxide nemamwe. Oiri inewo magasi muzvikamu zvakasiyana, asi magasi aya anoburitswa kuburikidza nefractional distillation kana kuti anogadzirwa nemamwe maitiro epadivi muzvicherwa. Minda yegasi yakasiyana zvikuru - gasi rakachena kana "yakaoma" (kureva, ine methane yakawanda) uye "yakanyorova" (ine methane, ethane, propane, mamwe magasi anorema, uye kunyange "peturu" - mvura yakareruka, zvikamu zvinokosha zvikuru) . Iwo marudzi emafuta akasiyanawo, uye kuwanda kwemagasi mavari kunogona kunge kwakaderera kana kwakakwirira. Minda inowanzobatanidzwa - gasi rinokwira pamusoro pemafuta uye rinoita se "gas cap". Kuumbwa kwe "cap" uye munda mukuru wemafuta unosanganisira zvinhu zvataurwa pamusoro apa, uye zvikamu zvakasiyana-siyana, nenzira yekufananidzira, "kuyerera" kune mumwe nemumwe. Iyo methane inoshandiswa sehuni yemotokari "inouya" kubva kugasi rechisikigo, uye musanganiswa wepropane-butane watinoziva unobva kune ese ari maviri magasi echisikigo neminda yemafuta. Inenge 6% yegasi repasi rose rinogadzirwa kubva mumarasha emarasha, ayo anowanzo kuperekedzwa nemadhipoziti egasi.
Propane-butane inoonekwa pachiitiko neimwe nzira inokatyamadza. Muna 1911, mutengi weAmerica akatsamwa wekambani yemafuta akaraira shamwari yake, nyanzvi yemakemikari Dr. Snelling, kuti awane zvikonzero zvechiitiko chinoshamisa. Chikonzero chekutsamwa kwevatengi ndechekuti mutengi anoshamisika kuona kuti hafu yetangi renzvimbo yekuzadza ichangobva kuzadzwa. Ford Iye akanyangarika nenzira dzisingazivikanwe panguva pfupi yekuenda kumba kwake. Iyo tangi haina kuyerera ichibva pasina kwa ... ivo. Imhaka yekufambira mberi kwakakosha uko Dr Snelling yava kunzi "baba" veindasitiri.
Zvakawanda zvisati zvaitika, anenge makore zviuru zvitatu apfuura, vafudzi vakawana "tsime rinopfuta" paGomo reParanas kuGreek. Gare gare, tembere ine mbiru dzinopfuta yakavakwa panzvimbo ino "inoera", uye chipenga Delphius akaverenga minamato yake pamberi peiyo huru colossus, zvichikonzera vanhu kunzwa pfungwa yekuyananisa, kutya uye kuyemura. Nhasi, kumwe kudanana uku kwakarasika nekuti tinoziva kuti panobva murazvo methane (CH3000) inoyerera ichibva pakatsemuka mumatombo inosangana nekudzika kweminda yegasi. Kune moto wakafanana munzvimbo dzakawanda muIraq, Iran neAzerbaijan kumahombekombe eGungwa reCaspian, ayo anga achitsvawo kwemazana emakore uye ave nenguva achizivikanwa se "Eternal Flames of Persia."
Makore akawanda gare gare, maChinese akashandisawo magasi kubva kuminda, asi nechinangwa chepragmatic - kupisa mabhoilers makuru nemvura yegungwa uye kubvisa munyu kubva mairi. Muna 1785, maBritish akagadzira nzira yekugadzira methane kubva mumarasha (iyo yakashandiswa mumajini ekutanga emoto mukati), uye mukutanga kwezana ramakore rechimakumi maviri, maGerman chemist Kekule naStradonitz vakapa mvumo yekugadzira mafuta anorema kubva mairi.
Muna 1881, William Hart akachera tsime rekutanga gasi muguta reAmerica reFredonia. Hart akatarisa mabubbles achikwira pamusoro pemvura mune imwe bay yaive pedyo kwenguva yakareba uye akasarudza kuchera gomba kubva pasi kuenda kunzvimbo yainzi gasi. Pahupamhi hwemamita mapfumbamwe pasi pepamusoro, akasvika patsinga iyo gasi rakabuda kunze, iyo yaakazotora gare gare, uye ichangobva kuumbwa Fredonia Gas Light Company akava piyona mubhizimisi regasi. Zvisinei, zvisinei nekubudirira kwaHart, gasi rekuvheneka rakashandiswa muzana remakore rechiXNUMX rakatorwa zvakanyanya kubva mumarasha nenzira yatsanangurwa pamusoro apa - zvakanyanya nekuda kwekushaikwa kwehunyanzvi hwekugadzira matekinoroji ekutakura gasi rechisikigo kubva kuminda.
Nekudaro, yekutanga kugadzirwa kwemafuta ekutengesa yaive yatove chokwadi ipapo. Nhoroondo yavo yakatanga muU.SA muna 1859, uye pfungwa yaive yekushandisa mafuta akabviswa kunyura parafini yekuvhenekesa nemafuta einjini dzechipfunga. Kunyange ipapo, vanhu vakatarisana nesimba rinoparadza regasi rechisikigo, rakatsikirirwa kwezviuru zvamakore muura hwenyika. Mapiyona eboka raEdwin Drake akapotsa afa mukati mokuchera kwokutanga kusina kurongwa pedyo neTitusville, Pennsylvania, apo gasi rakadeuka kubva pakakoromoka, mwoto mukuru wakavapo, uyo wakatakura midziyo yose. Nhasi, kushandiswa kwemafuta uye gasi minda inoperekedzwa nehurongwa hwezviyero zvakakosha kudzivirira kubuda kwemahara kwegasi rinopisa, asi moto uye kuputika hazvishamisi. Zvisinei, gasi rimwe chetero muzviitiko zvakawanda rinoshandiswa semhando ye "pombi" inosundira mafuta kumusoro, uye kana simba rayo richidonha, vanogadzira mafuta vanotanga kutsvaga uye kushandisa dzimwe nzira kuti vabvise "goridhe dema".
Nyika yemahydrocarbon magasi
Muna 1885, makore mana mushure mekuchera gasi kekutanga kwaWilliam Hart, mumwe muAmerica, Robert Bunsen, akagadzira mudziyo wakazozivikanwa se "Bunsen burner". Iyo yakagadzirwa inoshanda kudhiza uye kusanganisa gasi nemhepo muchikamu chakakodzera, icho chinogona kushandiswa pakupisa kwakachengeteka - ndicho chinopisa icho nhasi ndicho hwaro hwemazuva ano okisijeni nozzles yezvitofu nemidziyo yekudziya. Kugadzirwa kwaBunsen kwakavhura mikana mitsva yekushandiswa kwegasi rechisikigo, asi kunyangwe pombi yekutanga gasi yakavakwa kare muna 1891, mafuta eblue haana kuwana kukosha kwekutengesa kusvika Hondo Yenyika II.
Yakanga iri panguva yehondo iyo nzira dzakavimbika dzakakwana dzekucheka uye kuputika dzakagadzirwa, izvo zvakaita kuti zvikwanisike kuvaka simbi yakachengeteka gasi mapaipi. Zviuru zvemakiromita zvadzo zvakavakwa muAmerica mushure mehondo, uye pombi kubva kuLibhiya kuenda kuItaly yakavakwa mu60s. Madhipoziti makuru egasi chaiwo akawanikwawo muNetherlands. Zvinhu zviviri izvi zvinotsanangura zvirinani zvivakwa zvekushandisa compressed natural gas (CNG) uye liquefied petroleum gas (LPG) semafuta emotokari munyika mbiri idzi. Iko hukuru hwehurongwa hwekukosha huri kutanga kuwana gasi hunosimbiswa nechokwadi chinotevera - Reagan paakafunga kuparadza "Evil Empire" muma80s, akarambidza kugoverwa kwezvigadzirwa zvepamusoro-soro zvekuvaka pombi yegesi kubva USSR kuenda kuEurope. Kuripa zvinodiwa neEurope, kuvakwa kwepombi yegasi kubva kuNorway chikamu cheNorth Sea kuenda kune mainland Europe iri kukurumidza, uye USSR iri kurembera. Panguva iyoyo, kutengeswa kwegasi kunze kwenyika ndiko kwaive kunobva mari yakaoma yeSoviet Union, uye kushomeka kwakanyanya kwakakonzerwa nematanho eReagan kwakakurumidza kutungamirira kuzviitiko zvinozivikanwa zvenhoroondo zvekutanga kwema90.
Nhasi, demokrasi yeRussia inonyanya kupa gasi rechisikigo kune zvinodikanwa zvesimba reGermany uye mutambi mukuru wepasi rose munzvimbo ino. Kukosha kwegasi rechisikigo kwakatanga kukura mushure mematambudziko maviri emafuta e70s, uye nhasi ndiyo imwe yemasimba makuru emagetsi ekukosha kwe geostrategic. Parizvino, gasi rechisikigo ndiyo yakachipa yehuni yekudziya, inoshandiswa sechikafu muindasitiri yemakemikari, yekugadzira magetsi, yemidziyo yemumba, uye "cousin" yayo propane inogona kuwanikwa mumabhodhoro ezvinonhuwirira se deodorant. inotsiva ozone-depleting fluorine compounds. Kushandiswa kwegasi rechisikigo kuri kuramba kuchikura, uye gasi pombi network iri kuramba ichirebesa. Kana zviri zvezvivakwa zvakavakwa kusvika pari zvino zvekushandisa mafuta aya mumotokari, zvese zvakasara kumashure.
Takatokuudza pamusoro pezvisarudzo zvinoshamisa zvakaitwa nemaJapan mukugadzirwa kwemafuta aidiwa uye mashoma panguva yeHondo Yenyika Yechipiri, uye akataurawo chirongwa chekugadzirwa kwepeturu yekugadzira muGermany. Nekudaro, zvishoma zvinozivikanwa nezve chokwadi chekuti mumakore akaonda ehondo muGermany pakanga paine mota chaidzo dzaimhanya pa ... huni! Muchiitiko ichi, iyi haisi kudzoka kune yakanaka yekare injini injini, asi injini dzinopisa mukati, dzakagadzirirwa kushanda pa peturu. Muchokwadi, iyo pfungwa haina kuoma zvakanyanya, asi inoda kushandiswa kweyakakura, inorema uye ine njodzi gasi jenareta system. Marasha, marasha kana huni chete anoiswa mune yakakosha uye isiri yakanyanya kuoma simba chirimwa. Pasi payo, vanopisa mukushayikwa kweokisijeni, uye mumamiriro ekupisa kukuru uye unyoro, gasi rinobudiswa rine carbon monoxide, hydrogen uye methane. Inobva yatonhodzwa, yocheneswa, uye yodyiswa nefeni mumipumburu inopinza injini kuti ishandiswe sehuni. Ehe, vatyairi vemichina iyi vakaita mabasa akaoma uye akaoma evanodzima moto - iyo bhailer yaifanira kubhadhariswa nguva nenguva uye kucheneswa, uye michina yekuputa yainyatsoita senge dhizaini.
Nhasi uno, kuongorora gasi kunoda hunyanzvi hwehunyanzvi hwepasi rose, uye kutorwa kwegasi neoiri nderimwe rematambudziko makuru akatarisana nesainzi nehunyanzvi. Izvi zvinonyanya kuitika muU.S., uko nzira dzakawanda dzisina kujairika dziri kushandiswa ku "kuyamwa" gasi rakasara muminda yekare kana yakasiiwa, uyewo kubvisa iyo inonzi "yakasimba" gasi. Sekureva kwevesainzi, zvino zvava kuda kuchera zvakapetwa kaviri kugadzira gasi padanho rehunyanzvi muna 1985. Kubudirira kwemaitiro kunowedzera zvakanyanya, uye uremu hwemichina hwakaderedzwa ne75%. Zvirongwa zvemakombuta zviri kuwedzera zviri kushandiswa kuongorora data kubva kugiravimita, tekinoroji tekinoroji uye laser satellite, kubva kune matatu-dimensional emakombuta emamepu emadziva anogadzirwa. Izvo zvinonzi 4D mifananidzo yakagadzirwawo, nekuda kwazvinogoneka kuona mafomu uye mafambiro emadhipoziti nekufamba kwenguva. Nekudaro, zvivakwa zvechizvino-zvino zvinosara zvekugadzira gasi remugungwa - chikamu chidiki chete chekufambira mberi kwevanhu munzvimbo ino - masisitimu epasi rose ekuchera, kuchera kwakadzika, mapaipi epasi pegungwa, uye masisitimu ekubvisa mvura. carbon monoxide uye jecha.
Kukwenenzvera oiri kuti ibudise peturu yemhando yepamusoro ibasa rakaoma zvikuru kupfuura kuchenesa magasi. Ukuwo, kutakura gasi nomugungwa kunodhura zvikuru uye kwakaoma kunzwisisa. LPG matangi akaomarara mukugadzira, asi LNG vatakuri chisikwa chinoshamisa. Butane inonyungudika pa -2 madhigirii, ukuwo propane ichinyungudika pa -42 madhigirii kana kuti yakaderera. Nekudaro, zvinotora -165 madhigirii kunyungudutsa methane! Nekuda kweizvozvo, kuvakwa kweLPG matangi kunoda zviri nyore compressor zviteshi pane zvegasi rechisikigo uye matangi akagadzirirwa kutsungirira kwete kunyanya kudzvinyirirwa kwe20-25 bar. Kusiyana neizvi, matangi egasi egasi ane liquefied ane anoenderera kutonhora masisitimu uye super-insulated matangi - kutaura zvazviri, aya colossi ndiwo makuru epasirese cryogenic mafiriji. Zvisinei, chikamu chegasi chinokwanisa "kusiya" zvigadziro izvi, asi imwe hurongwa inobva yaitora uye inoidyisa mumasilinda einjini yechikepe.
Nokuda kwezvikonzero zviri pamusoro apa, zvinonzwisisika kuti kare muna 1927 teknolojia yakabvumira matangi ekutanga epropane-butane kurarama. Iri ndiro basa reDutch-English Shell, iyo panguva iyoyo yakanga yatova kambani huru. Mukuru wake Kessler murume wepamberi uye muyedzeri anga achishuvira kushandisa neimwe nzira huwandu hukuru hwegasi kusvika parizvino ranyudza mumhepo kana kupiswa mumichina yekuchenesa oiri. Papfungwa yake uye danho rake, ngarava yekutanga yekumahombekombe ine simba rekutakura matani 4700 yakagadzirwa kuti itakure magasi ehydrocarbon ane zvimiro zvinotaridzika uye zvinoyemurika pamusoro pematangi edhisiki.
Zvakadaro, mamwe makore makumi matatu nemaviri anodiwa kuvaka yekutanga Methane Pioneer methane carrier, yakavakwa nehurongwa hwekambani yegasi yeConstock International Methane Limited. Shell, iyo yatove neyakagadzika gadziriro yekugadzira uye kugovera LPG, yakatenga kambani iyi, uye munguva pfupi yakatevera mamwe matangi makuru maviri akavakwa - Shell yakatanga kuvandudza bhizinesi regasi rechisikigo. Kana vagari vechitsuwa cheChirungu cheConway, uko kambani iri kuvaka nzvimbo dzekuchengetera methane, vanoziva izvo chaizvo zvakachengetwa uye kuendeswa kuchitsuwa chavo, vanovhunduka uye vanotya, vachifunga (uye zvakakodzera) kuti zvikepe zvinongori mabhomba makuru. Ipapo dambudziko rekuchengetedza raive rakakosha, asi nhasi matangi ekutakura methane ine liquefied akachengeteka zvakanyanya uye haisi imwe chete yeakachengeteka, asiwo imwe yezvikepe zvegungwa zvine hushamwari - zvakachengeteka zvisingaenzaniswi kune zvakatipoteredza kupfuura matangi emafuta. Mutengi mukuru wezvikepe zvinotakura matangi iJapan, iyo inenge isina simba renzvimbo, uye kuvaka mapaipi egasi kuchitsuwa ibasa rakaoma kwazvo. Japan zvakare ine "paki" yakakura kwazvo yemotokari dzegasi. Vatengesi vakuru ve liquefied natural gas (LNG) nhasi iUnited States, Oman neQatar, Canada.
Munguva pfupi yapfuura, bhizinesi rekugadzira mvura yema hydrocarbons kubva kugasi rechisikigo rave kuwedzera mukurumbira. Iyi inonyanya kuchena-yakachena dhiziri inogadzirwa kubva kumethane, uye indasitiri iyi inotarisirwa kusimukira nekukurumidza mune ramangwana. Semuenzaniso, mutemo weBush wesimba unoda kushandiswa kwesimba renzvimbo, uye Alaska ine madhipoziti makuru egasi. Aya maitiro anokurudzirwa nemitengo yemafuta yakakwira, izvo zvinogadzira zvinodikanwa zvekuvandudza matekinoroji anodhura - GTL (Gasi-ku-Liquids) ingori imwe yadzo.
Chaizvoizvo, GTL haisi tekinoroji nyowani. Yakagadzirwa muma20s nemaGerman chemist Franz Fischer naHans Tropsch, vakambotaurwa munyaya dzakapfuura sechikamu chechirongwa chavo chekugadzira. Nekudaro, mukusiyana nekuparadza hydrogenation yemarasha, maitiro ekubatanidza mamorekuru emwenje mumabhondi akareba anoitika pano. South Africa yanga ichigadzira mafuta akadaro pamwero weindasitiri kubva kuma50. Zvisinei, kufarira kwavari kwakakura mumakore achangopfuura mukutsvaga mikana mitsva yekuderedza kusvibiswa kwemafuta anokuvadza muUnited States. Makambani makuru emafuta akadai seBP, ChevronTexaco, Conoco, ExxonMobil, Rentech, Sasol neRoyal Dutch/Shell vari kushandisa mari hombe mukugadzira matekinoroji ane hukama neGTL, uye nekuda kwezvinoitika izvi, zvematongerwo enyika nemagariro zviri kuramba zvichikurukurwa. chiso chekukurudzira. mitero pavatengi vemafuta akachena. Mafuta edzimotokari aya achabvumira vazhinji vanoshandisa mafuta edhiziri kuti vaatsive voshandisa zvakatipoteredza uye zvichaderedza mutengo kumakambani emotokari kuti asangane nemwero mitsva yehutsi hunokuvadza hunotarwa nemutemo. Munguva pfupi yapfuura kuongororwa kwakadzama kunoratidza kuti mafuta eGTL anoderedza kabhoni monoxide ne90%, mahydrocarbon ne63% uye soot ne23% pasina kudiwa kwemasefa edhiziri. Mukuwedzera, iyo yakaderera-sarufa yemafuta iyi inobvumira kushandiswa kwezvimwe zvinokonzeresa izvo zvinogona kuwedzera kuderedza kuburitswa kwemotokari.
Mukana wakakosha weGTL mafuta ndewekuti inogona kushandiswa zvakananga mumainjini edhiziri pasina chero shanduko kumayuniti. Izvo zvinogona zvakare kusanganiswa nemafuta ane 30 kusvika 60 ppm sarufa. Kusiyana negasi rechisikigo uye gasi remafuta epeturu, hapana chikonzero chekuchinja zvivakwa zvekufambisa zviripo kutakura mafuta emvura. Sekureva kweMutungamiriri weRentech, Denis Yakubson, mhando yemafuta iyi inogona kuzadzikisa hunyanzvi hwehupfumi hweinjini yedhiziri, uye Shell parizvino iri kuvaka chirimwa hombe chemadhora mazana mashanu emadhora muQatar ine dhizaini yemamirioni makumi maviri nemaviri emamiriyoni emafuta ekugadzira pazuva. ... Dambudziko rakakura nemafuta aya rinobva mukudyara kukuru kunodiwa muzvivakwa zvitsva uye neyakajairika nzira yekugadzira.
Biogas
Zvisinei, kunobva methane hakusi kungoisa pasi pevhu chete. Muna 1808 Humphry Davy akaedza nehuswa hwakaiswa muvacuum retort uye akagadzira biogas ine methane, carbon dioxide, hydrogen nenitrogen. Daniel Defoe anotaurawo nezve biogas mubhuku rake pamusoro pe "chitsuwa chakarasika". Zvisinei, nhoroondo yepfungwa iyi yakatokura - muzana remakore rechi1776, Jan Baptita Van Helmont aidavira kuti magasi anopisa anogona kuwanikwa kubva pakuparara kwezvinhu zvakasikwa, uye Count Alexander Volta (muumbi webhatiri) akasvikawo pakufunga kwakafanana. muna 1859. Chekutanga biogas chirimwa chakatanga kushanda muBombay uye chakavambwa mugore rimwechete iro Edwin Drake akagadzira yekutanga yakabudirira kuchera oiri. Chirimwa chekuIndia chinogadzira tsvina uye chinopa gasi kumarambi emumigwagwa.
Zvinotora nguva yakareba makemikari maitiro mukugadzirwa kwe biogas akanyatsonzwisiswa uye kudzidza. Izvi zvakagoneka chete muma30s ezana ramakore XX uye ndiwo mhedzisiro yekusvetuka mukukudziridzwa kwehutachiona. Zvinoitika kuti maitiro aya anokonzerwa neanaerobic bacteria, ayo ari mamwe ehupenyu hwakare hupenyu paPasi. Ivo "vanokuya" zvinhu zvakasikwa munzvimbo ine anaerobic nharaunda (kuora kweaerobic kunoda oxygen yakawanda uye kunogadzira kupisa). Maitiro akadaro anoitikawo zvakasununguka mumatope, madhaka, minda yepaddy, akafukidzwa madhibhi, nezvimwe.
Masisitimu emazuva ano ekugadzirwa kwebiogas ari kuwedzera mukurumbira mune dzimwe nyika, uye Sweden inotungamira mune zvese kugadzirwa kwebiogas uye mota dzakagadziridzwa kuti dzishande pairi. Synthesis units inoshandisa yakanyatsogadzirwa biogenerators, isingadhuri uye yakapusa michina inogadzira nzvimbo yakakodzera yebhakitiriya, iyo, zvichienderana nerudzi rwavo, "inoshanda" zvakanyanya pakudziya kubva ku40 kusvika 60 madhigirii. Zvigadzirwa zvekupedzisira zvezvirimwa zvebiogas, mukuwedzera kune gasi, zvakare zvine makomisheni akapfuma muammonia, phosphorus uye zvimwe zvinhu zvakakodzera kushandiswa mukurima sefetiraiza yevhu.
