A cikin yanayi mara kyau na ofishin ƙira, kushin leach ɗin ya zama cikakkiyar jirgin sama na geometric. A cikin ƙaƙƙarfan gaskiyar wurin da ake hakar ma’adinan, ƙasa tana raye—tana juyawa, tana matsawa, ta kuma zauna ƙarƙashin nauyin miliyoyin ton na tama. Lokacin da wannan sulhu ya faru ba daidai ba, yana mai da tsarin ajiyar ku zuwa bam na lokaci mai karewa. Na ga ayyukan da layin layi ya wuce kowane gwajin walƙiya na QA yayin shigarwa, kawai ya sha fama da bala'in leaks bayan shekaru uku saboda tushe ya lafa, yana shimfiɗa geomembrane sama da ƙimarsa.

Jagoran mai zuwa yana nazarin injiniyoyi na gazawar da aka haifar da sulhu a ayyukan leach. Ya bayyana dalilin da ya sa bambance-bambancen sulhu shine babban abokin gaba na mutuncin layi, yadda nau'i-nau'i masu yawa ke lalata HDPE da LLDPE a tsawon lokaci, da kuma dabarun aiki-daga shirye-shiryen ƙaddamarwa zuwa zaɓi na polymer-cewa injiniyoyin ma'adinai da jami'an siyan kaya dole ne su yi amfani da su don hana bala'o'in muhalli.

Rashin gazawar injin leach line saboda sasantawa ba kasafai wani lamari ne da ke faruwa a dare daya ba. Rikici ne mai saurin motsawa wanda ke farawa lokacin da manyan motoci na farko na tama suna taimakawa damfara da ƙasa. Don hana shi, dole ne mu fahimci ainihin abin da ke faruwa a ƙarƙashin baƙar fata.

1. Menene Matsala a Ayyukan Leach Leach?

Lokacin da muka samar da geomembranes don ayyukan hakar ma'adinai, musamman tarin leach pads, tambayar fasaha ta farko bai kamata kawai ta kasance game da juriyar sinadarai na HDPE ba; ya kamata ya kasance game da injiniyoyin ƙasa na tushe. Matsala, a cikin wannan mahallin, motsi ne na ƙasa a tsaye yana goyan bayan kushin da ya haifar da raguwar ƙarar ƙurar ƙasa.

A cikin manyan hako ma'adinai, sulhu ba wani abu ba ne; babu makawa. Kuna sanya kaya na cikin gida wanda zai iya wuce mita 100 tsayi, yana yin matsi mai yawa a kan ƙasa. Daga mahangar mutuncin layi, mun kasasu wannan zuwa matakai daban-daban guda uku:

Zaure kai tsaye

Wannan yana faruwa kusan nan take yayin da aka tara ma'adinan. Yana da nakasar busasshiyar ƙasa da dutse. Don layin layi, yawanci ana iya sarrafa wannan saboda kayan na iya ƙara ɗanɗano kaɗan don ɗaukar canjin siffar kamar yadda ya faru.

Haɗin Farko

Wannan shine lokaci mai haɗari don cikakken yumbu subgrades. Yayin da nauyin tsibin ya matsa ƙasa, ana matse ruwa daga cikin babur ƙasa na tsawon makonni ko watanni. Wannan raguwar ƙarar yana sa ƙasa ta nutse. Idan magudanar ruwan ƙasa ba ta yi daidai ba, nutsewar ba ta yi daidai ba, tana haifar da wuraren damuwa da ke kan layin.

Tsawon Lokaci (Na biyu) Matsala

Often called "creep," this occurs over years a constant load reshapes the soil structure itself. I have consulted on cases where a liner failed five years into operation. The operators were baffled because "nothing changed." Amma ƙasa a ƙasa, ƙasa tana ta rarrafe a hankali, a ƙarshe tana tura geomembrane ta wuce wurin samar da ita.

Effective export and supply of these materials require us to ask: "What is your calculated settlement timeline?" Idan mai siye bai sani ba, suna siyan abin alhaki ne ba mai layi ba.

2. Me Yasa Matsala Yana Da Muhimmanci Amma Sau da yawa Ba'a La'akari da Haɗari

Mafi hatsarin al'amari na sulhu shine rashin ganin sa. Sau ɗaya a heap leach pad yana aiki, an binne layin a ƙarƙashin ton na niƙaƙƙen tama, bututun magudanar ruwa, da mafita. Ba za ku iya duba layin gani ba don fashewar damuwa ko bakin ciki da zarar an fara aiki.

The "Lag Time" Tarko

A cikin gogewar da na yi game da sayan nawa, akwai mai da hankali sosai kan ingancin shigarwa-gwajin walda, gwaji mai lalacewa, da gwajin matsa lamba na iska. Wadannan suna da mahimmanci, amma kawai suna tabbatar da cewa layin ba shi da kyau a lokacin zero. Matsala na tasowa sannu a hankali. Mai layi na iya yin aiki daidai a cikin shekara ta 1, yana tara damuwa a cikin shekara ta 2, kuma yana raguwa a cikin shekara ta 3.

Gyara ba Zabi bane

Idan layin layi ya gaza saboda lalacewar injina yayin shigarwa, kuna faci. Idan layin layi ya kasa saboda daidaitawa a ƙarƙashin tulin mita 50, ba ku da wata hanya mai sauƙi don gyara shi. Ba za ku iya ɗaga dutsen tama ba. Mafita ɗaya ce sau da yawa don gina sabon yanki na gaggawa ko yarda cewa kuna asarar maganin ciki (da zinari/farin jan karfe) kai tsaye zuwa cikin muhalli.

Wannan yana sanya nauyin nauyi akan tsarin ƙira da zaɓin kayan aiki. Sau da yawa muna gaya wa abokan cinikinmu: Ba kawai kuna siyan shinge ba; kana sayen membrane wanda dole ne ya tsira daga canjin yanayi.

3. Nau'o'in Mazaunan da ke Shafar Tushen Leach Leach

Ba duk nutsewa aka halicci daidai ba. Fahimtar lissafi na matsugunin yana ƙayyade ko layin naku zai tsira ko ya gaza.

Matsakaicin Uniform

Idan duk kushin leach ɗin ya nutse cikin 50cm daidai, geomembrane gabaɗaya yana da kyau. Mai layi yana motsawa tare da ƙasa azaman raka'a ɗaya. Akwai ɗan damuwa mai ƙarfi da aka haifar saboda farfajiyar kafuwar bai ƙaru sosai ba; ya sauko a sama.

Matsakaici Bambance: The Liner Killer

Wannan shi ne yanayin da ke sa injiniyoyi su tashi da dare. Bambance-bambance yana faruwa ne lokacin da wani ɓangare na tushe ya nutse fiye da ɓangaren da ke kusa.

• Misali: Ɗayan gefen kushin yana zaune a kan gadon gado, ɗayan kuma yana zaune a kan kwarin da aka cika da ƙasa.
  As the fill settles and the bedrock doesn't, a "transition zone" yana haifar da tudu ko mataki. Mai layin da ke daidaita wannan tazarar an tilasta masa mikewa. Idan nau'in da ake buƙata don cike wannan ratar ya zarce girman yawan amfanin layin, zai karye.

Rushewar Gida (Kogo)

In some regions, particularly where we export to mining belts with karst topography or soluble subgrades, voids can open up underneath the pad. This creates a circular depression—a "sinkhole" tasiri. Daga nan sai a tilasta mai layin ya yi aiki azaman gungumen da aka dakatar yana goyan bayan ma'adinin da ke sama. Babu daidaitaccen geomembrane da aka ƙera don ɗaukar nauyin tsarin takin tama akan fanko.

4. Yadda Zaure Ke Haɗuwa Geomembrane Liner Failure

To select the right material, you must understand the failure mechanism. It is rarely a simple "snap." Yana da ci gaba da gajiyar ƙarfin kayan.

Haɓaka Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙashin Ƙarƙwara

Geomembranes, musamman Polyethylene Mai Girma (HDPE), are semi-crystalline polymers. They have a distinct "yield point." A cikin gwajin tensile na Lab, HDPE yana haifar da kusan 12-15% iri. Da zarar ya wuce abin da ake samu, sai ya shiga cikin kewayon nakasar filastik inda yake baci ba tare da juyewa ba (wuyansa).
A cikin yanayin daidaitawa, ƙasa tana jan layin. Idan layin yana ci gaba da kasancewa ta hanyar juzu'in ma'adinin da ke sama da shi, ba zai iya zamewa don rage tashin hankali ba. Maimakon haka, yana shimfidawa a cikin gida. Idan shimfidawar gida ta wuce wurin samar da amfanin gona, tsarin polymer ya rushe.

Matsakaicin Matsakaicin Matsalolin Anchor Trenches

The anchor trench is where the liner is buried to hold it on the slope. When the pad settles, the liner wants to move down into the depression. But the anchor trench holds it tight. The result is massive tension at the crest of the slope—right where the liner exits the trench. We often see failures at the top of the berm, not the bottom, because the liner was essentially "hung" ta wurin taro.

Multi-Axial vs. Uni-Axial Strain

Standard data sheets show "Elongation at Break" dangane da ja da tsiri a hanya ɗaya (uni-axial). Amma sulhu yana haifar Multi-axial iri- jan kayan a cikin kwatance 3D lokaci guda kamar fatar ganga. HDPE yana nuna halin ɓarna-y a ƙarƙashin damuwa mai yawa fiye da yadda yake yi a gwajin ja na layi. Wannan bambance-bambance ne mai mahimmanci wanda yawancin masu siye ke kau da kai lokacin karanta takaddun bayanai.

5. Hannun gazawar gama gari da ke da alaƙa ana lura da su a cikin mashin leach

Daga shari'o'in fitar da mu da kuma binciken gazawar bayan faduwa, takamaiman alamu suna fitowa lokacin sasantawa shine mai laifi.

Tsagewar Liner Tearing

Wannan yana kama da dogon slash mai gudana daidai da gangare ko yankin nakasa. Yana faruwa ne saboda an shimfiɗa layin a gefe har sai an raba sarƙoƙin polymer. Waɗannan hawayen na iya zama tsayin mitoci kuma suna da lahani ga ɗaukar ciki.

Kabu da Rabuwa

Fusion waldi ( weld weld) ya fi kauri da ƙarfi fiye da takardar kanta. Lokacin da ƙasa ta daidaita kuma layin layi ya shimfiɗa, damuwa yana neman hanyar mafi ƙarancin juriya. Tun da walda ɗin yana da tauri/tauri, damuwa yana mai da hankali kusa da walda a Yankin da Ya Shafi Zafi (HAZ).
Mu akai-akai muna ganin fashe-fashe suna tafiya a layi daya da dunƙulewar walda. Weld din bai karye ba; layin ya karye saboda walda ba zai tanƙwara ko mikewa ba kamar takardar da ke kewaye.

Wrinkle Blocking ("Whale Mouths")

In hot climates, liners expand and create wrinkles during installation. If these wrinkles are flattened down by the ore load and then subjected to settlement, the folded plastic is pinched and stressed. This creates a "crease cracking" al'amari, mai kama da lankwasa faifan takarda baya da baya har sai ya tsage.

6. Mahimman Abubuwan da ke Ƙara Haɗarin Matsala a cikin Ayyukan Leach Leach

Idan kuna shirin aiki a halin yanzu, tantance waɗannan abubuwan zai gaya muku idan kuna buƙatar haɓaka ƙayyadaddun bayanan layin ku.

Compressible or Heterogeneous Subgrade

If your site requires significant "cut and fill" (cutting into a hill and using that soil to fill the valley), you are creating a heterogeneous foundation. The "cut" side is hard; the "fill" gefe yayi laushi. Wannan shine girke-girke na #1 don daidaitawa daban.

Heap Heap

The relationship is linear: more height = more weight = more settlement. As mines move to "valley fill" leach pads wanda zai iya zama zurfin mita 100+, daidaitaccen 1.5mm HDPE ana tura shi zuwa iyakar injin sa.

Talakawa Shiri

Wani lokaci lokutan lokaci suna takura. Mun ga 'yan kwangila sun yi tsalle a kan ƙaddamar da ƙananan yadudduka, suna samun kawai 85% Proctor density maimakon 95% ko 98%. Da zaran an ɗora ma'adinan, wannan ɓataccen ma'aunin yana samuwa ta hanyar gaggawa, ba tare da kulawa ba.

Tasirin Zazzabi

If a liner is installed at 40°C (expanded) and then covered with cold ore/solution at 10°C, it tries to shrink. This creates "thermal tension." Ƙara tashin hankalin daidaitawa a saman tashin hankali na thermal, kuma yanayin aminci na kayan yana ƙafe.

7. Dabarun ƙira don Rage gazawar Liner da ke haifar da Matsala

A matsayin mai ba da mafita, muna jaddada cewa ba za ku iya magance matsalar ilimin lissafi ba tare da takardar filastik kawai. Magani yana farawa da zane.

Subgrade Improvement and Preloading

Hanyar da ta fi dacewa ita ce tabbatar da sulhu ya faru kafin the liner is installed. This often involves "surcharging" ko preloading wurare masu laushi tare da ƙasa don tilasta ƙarfafawa, sannan cire shi don shigar da layin.

Matsakaicin Matsala Tsari

Loda kushin da sauri yana haifar da matsananciyar ruwa mai yawa a cikin ƙasa, yana haifar da zamewa da sauri da daidaitawa. Ta hanyar rage yawan tari, kuna ba da damar juzu'i don magudana da daidaitawa a hankali, rage girgiza zuwa tsarin layi.

Inganta Geometry na gangara

Matsakaicin sauye-sauye sune wuraren gazawa. Idan ƙira ta buƙaci mataki na tsaye ko canji mai kaifi a cikin sa, koyaushe muna ba da shawarar smoothing shi. Matsakaicin 3:1 yana ba mai layi damar yin tsawo cikin aminci fiye da digo kusa da tsaye.

Designing "Slip Layers"

A cikin wuraren da ake tsammanin sasantawa, wasu lokuta muna ba da shawarar ƙirar ƙanƙara. Ta hanyar sanya takamaiman geotextile ko geonet a ƙarƙashin geomembrane, muna rage kusurwar juzu'i tsakanin ƙasa da layin layi. Wannan yana ba da damar layin layi ya zame dan kadan don rage tashin hankali, maimakon a kulle shi a wuri kuma a tilasta masa mikewa.

8. Zaɓan Geomembranes don Matsuguni-Masu Matsuguni na Leach Leach Pads

Anan shine inda shawarar siyayya ta shafi bayanin haɗarin kai tsaye. Ba duk geomembranes ke gudanar da sulhu daidai ba.

HDPE vs. LLDPE: Canjin Canjin Sauƙi

Standard HDPE (High-Density Polyethylene) shine ma'auni na masana'antu don juriya na sinadarai da kwanciyar hankali UV. Duk da haka, yana da m. Yana da babban mahimmin yawan amfanin ƙasa amma ƙarancin jurewar iri iri-iri.
LLDPE (Linear Low-Density Polyethylene) ya fi sassauƙa. Yana nuna hali kamar bandejin roba. Ba shi da takamaiman ma'anar yawan amfanin ƙasa kuma yana iya haɓakawa sosai a ƙarƙashin damuwa mai yawa-axial ba tare da raguwar bala'i ba.

• Shawarar Mu: Don pads tare da babban bambance-bambancen da aka annabta, galibi muna ba da shawarar amfani da LLDPE don tushen layi, ko takamaiman resins HDPE da aka gyara waɗanda ke ba da ductility mafi girma.

Kauri da Asperities

Yayin da 1.5mm daidai yake, haɓaka zuwa 2.0mm yana ba da ƙarin ɓangaren giciye na kayan don tsayayya da ƙarfin ƙarfi. Duk da haka, thicker kuma yana da ƙarfi. Ya kamata a mai da hankali kan ingancin guduro. Muna neman resins tare da high "Juriya Crack Danniya" (ESCR > 500 hours ko ma > 1000 hours). Babban ESCR yana hana ƙananan fashe-fashe waɗanda ke tasowa yayin sasantawa daga yadawa cikin cikakkun hawaye.

Muhimmancin Asperities (Texture)

Rubutun layi suna ba da kwanciyar hankali ga gangara (riƙe da ma'adinai a kan gangara). Koyaya, a cikin manyan wuraren zama, matsananciyar rubutu yana kulle layin zuwa matakin ƙasa, yana hana damuwa. Ayyukan daidaitawa ne. Wani lokaci a layi mai laushi mai gefe guda shine madaidaicin zaɓin fasaha — gefe mai rubutu (don kwanciyar hankali), gefen ƙasa mai santsi (don ba da damar zamewa / damuwa akan ƙasa).

9. Me yasa Zane-Mai Tsaya Tsare-tsaren Liner Yana Bukatar Kwarewar Fasaha

This is where dealing with a "commodity trader" vs. an "industry specialist" yana kawo bambanci.

Matsala Matsala ce ta Tsari

You cannot buy a "settlement-proof" layin layi. Dole ne ku ƙirƙira mai jure sulhu tsarin. Wannan ya ƙunshi hulɗar ƙasa, matashin geotextile, geomembrane, da magudanar ruwa. Idan muka ga oda don 1.5mm HDPE amma babu takamaiman bayani ga matashin geotextile (wanda ke kare layin daga huda. da yana ba da damar rarraba iri), muna ba da alama nan da nan.

Hadarin Ƙarƙashin Ƙira

Na ga masu siye suna ajiye $0.20/m² ta hanyar zabar resin ƙaramin daraja ko tsallake shingen geotextile. Idan wannan kushin ya daidaita kuma yana hawaye, farashin asarar mafita da gyaran muhalli zai wuce ƙimar layin farko ta 1000x.

Shawarar Dillali

ƙwararrun masu samar da kayayyaki na iya duba rahoton ƙaramar ku kuma su ba da shawarar gyare-gyare. Alal misali, a cikin wani aikin kwanan nan tare da tushe mai laushi mai laushi, mun ba da shawarar wani ƙayyadaddun haɓakaccen haɓakaccen haɓakaccen geomembrane wanda ya haɗu da juriya na sinadarai na HDPE akan farfajiya tare da madaidaicin LLDPE mai sassauƙa. Wannan tsarin haɗin gwiwar ya ba da shingen sinadari da doka ke buƙata amma sassaucin da ilimin ƙasa ke buƙata.

Haɗari, Iyakoki, da Lokacin da Liners Ba Magani ba ne

Wajibi ne a bayyana wannan a sarari: Geomembrane liner ba gada ce ta tsari ba.

Idan rukunin yanar gizon ku yana fuskantar haɗarin kwatsam, rugujewar bala'i (kamar rugujewar ruwa wanda ya fi mita 1-2 a diamita), babu adadin kauri ko injin polymer da zai cece ku.

• Iyakance Ƙunƙasa: Ko da mafi kyawun LLDPE na iya gada ƙananan ɓata kawai. Manya-manyan kuraje za su sa layin ya yi rauni har sai ya fashe.
• Kasawar Shear: Idan sulhu ya haifar da gazawar gangara (zabtarewar ƙasa) na ƙasa, ƙasa mai motsi za ta shredded layin.

In these extreme cases, the solution is not "better plastic." Mafita shine Ƙarfafa geogrid ko shiga tsakani na injiniyan jama'a (grouting, shingen kankare) don daidaita ƙasa kafin a buɗe kowane layi. Kada ka dogara ga geomembrane don ɓoye mummunan tushe.

Ƙarshe

Matsawa cikin ayyukan leach leach ƙalubale ne na karon ilimin geology, physics, da sunadarai. Rashin gazawar layin layi saboda sasantawa kusan koyaushe shine gazawar hasashe da shiri, ba kawai gazawar filastik da kanta ba.

Ga masu siye da injiniyoyi masu hakar ma'adinai, abin da za a yi ya fito fili: Kar a ɗauki layin layi azaman shingen tsaye. Abu ne mai ƙarfi wanda dole ne ya motsa da jujjuyawa tare da tudun ku. Ta hanyar yin la'akari da haɗarin raguwa da gaskiya, zabar resins tare da babban juriya mai yawa-axial (kamar LLDPE ko HDPE mai girma), da kuma tsarawa don zamewa da sauƙi, za ku iya tabbatar da cewa tsarin tsarin ku yana ɗaukar nauyi mai nauyi na ma'adinai ba tare da karyewa a ƙarƙashin matsin lamba ba.

Idan a halin yanzu kuna kimanta zaɓuɓɓukan layin layi don rukunin yanar gizon da ke da yanayin ƙasa mai wahala, tuntuɓe mu. Ba kawai mu sayar da nadi ba; muna taimaka muku saita yadudduka don tsira da daidaitawa.