Gold Cyanidation Plant Cyanide Wastewater Treatment Njira

In Chomera cha Gold Cyanidations, ngakhale zina Madzi a Cyanide ndi zobwezerezedwanso, zilipobe cyanide madzi oipa kapena zotsalira za cyanide zikutayidwa. Cyanide ndi yapoizoni kwambiri, choncho chithandizo chaukatswiri chamadzi otayira a cyanide n'chofunika asanatulutsidwe kuti apewe kuwononga chilengedwe komanso kuwononga thanzi la anthu ndi nyama. Pakadali pano, zotsatirazi ndi njira zodziwika bwino zochizira madzi a cyanide muzomera zagolide za cyanidation.

Njira Zochizira Madzi Otayira a Cyanide Apakati ndi Otsika

Njira ya Alkaline Chlorination

Njira ya alkaline chlorination ndi njira yomwe imagwiritsidwa ntchito kwambiri. Mwanjira iyi, chlorine oxidant yokhala ndi makutidwe ndi okosijeni wambiri imawonjezeredwa kumadzi otayidwa amchere a cyanide. Ma okosijeni wamba amaphatikizapo ClO₂, Cl₂ (gasi ndi madzi), ufa wowulira, sodium hypochlorite, calcium hypochlorite, ndi chlorite. Mu njira ya alkaline, OCl⁻ kapena high-charge chloride oxidation nthawi zambiri amapangidwa. Choyamba, cyanide ndi oxidized kuti cyanate, kenako oxidized kuti carbon dioxide ndi asafe.

• ubwino: Ma reagents amapezeka kwambiri komanso otsika mtengo. Zotsatira za chithandizo ndi zabwino, ndipo zida zomwe zimagwiritsidwa ntchito ndizosavuta, zomwe zimakhala zosavuta kuzipanga zokha.

• kuipa: Popeza kuti cyanogen chloride yopangidwa ndi poizoni, imakhala yovulaza kwambiri kwa ogwira ntchito. Cyanogen chloride ikakumana ndi madzi imatha kutulutsa utsi wowononga, kuwononga zida kwambiri.

Njira ya Inco

Njira ya Inco inapangidwa ndi Inco Ltd. mu 1982. Zimaphatikizapo kuwonjezera chisakanizo cha SO₂ ndi mpweya kumadzi onyansa a cyanide ndikuwongolera pH mtengo pakati pa 8 - 10. Ma ions amkuwa a divalent amachititsa kuti okosijeni wa cyanide awonongeke m'madzi onyansa.

• ubwino: Njira ya Inco ndiyosavuta, ndipo zida zomwe zimagwiritsidwa ntchito sizovuta. Mphamvu yamankhwala nthawi zambiri imakhala yabwinoko kuposa njira ya chlorination (popanda kuganizira za kawopsedwe ka thiocyanate). The reagent magwero ndi lonse, ndi ndalama ndi m'munsi kuposa ndondomeko zamchere chlorination.

• kuipa: Njira ya Inco imavuta kutulutsa oxidizing SCN⁻, ndipo SCN⁻ imatha kusiyanitsa CN⁻ pambuyo pake, kotero siyoyenera kuthira madzi onyansa a cyanide okhala ndi SCN⁻. SO₂ imawononganso mpweya ndipo imatha kuthawa ndikuchucha panthawi yakuchita, kuwononga chilengedwe.

Njira ya H₂O₂ Oxidation

Pansi pa mtengo wa pH wa 9.5 - 11. kutentha kwabwino, ndi ma ions amkuwa (Cu²⁺) monga chothandizira, H₂O₂ imatulutsa cyanide kupanga CNO⁻. CNO⁻ idzapangidwanso hydrolyzed kuti ipange NH₄⁺ ndi CO₃²⁻, ndipo kuchuluka kwa hydrolysis kumadalira pH.

• ubwino: Zotsatira za mankhwala a cyanide madzi onyansa ndi abwino, ndipo ndondomekoyi ndi yosavuta. Njira yamakutidwe ndi okosijeni ndiyoyenera kuchiza madzi otsika a cyanide, ndipo ndende ya cyanide pambuyo pa chithandizo ndi yochepera 0.5mg/L.

• kuipa: H₂O₂ ndi yapoizoni komanso ikuwononga, choncho mayendedwe ake ndi kagwiritsidwe ntchito kake ndi koopsa. Njira ya okosijeni imavuta kutulutsa SCN⁻ m'madzi otayira, ndipo madzi otayira oyeretsedwa akadali oopsa.

Njira ya Ozone Oxidation

Ozone ili ndi mphamvu yamphamvu kwambiri ya okosijeni, yokhala ndi mphamvu ya elekitirodi ya 2.07mV, yachiwiri pambuyo pa fluorine. Imatha kuwola mosavuta zigawo zomwe sizingawonongeke ndi ma okosijeni ena. Kapangidwe kake kachitidwe ka ozoni oxidation ndikuti ozoni imakumana ndi cyanide kupanga cyanide, yomwe imapangidwa ndi hydrolyzed kuti ipange nayitrogeni ndi carbonate.

• ubwino: Zimangofunika zida zopangira ozoni ndipo sizifunikira kugula ndi kunyamula mankhwala. Njirayi ndi yosavuta komanso yabwino, popanda kuipitsa yachiwiri.

• kuipa: Chifukwa cha kukwera mtengo kwa majenereta a ozoni komanso kuvutikira kwa kukonza zida, pali zolepheretsa pakugwiritsa ntchito mafakitale. Njira ya ozoni oxidation imagwiritsa ntchito magetsi ambiri, choncho zimakhala zovuta kugwiritsa ntchito m'madera omwe alibe mphamvu zokwanira.

Njira Zochiritsira Zapamwamba - Kuyika kwa Madzi a Cyanide

Njira ya Acidification

Njira ya acidification imatha kuchiza njira zambiri zamtundu wa cyanide (60 × 10⁻⁶ + NaCN) zotulutsidwa m'mafakitale. Kuchuluka kwa ayoni a cyanide aulere mu yankho kumatha kuchepetsedwa kukhala 1 × 10⁻⁶.

• ubwino: Itha kukulitsa kuchira kwa cyanide, kubwezeretsanso zinthu, ndipo imakhala ndi phindu lalikulu pazachuma.

• kuipa: Ndalama za nthawi imodzi ndizokulirapo, ndipo mabizinesi ang'onoang'ono ndi apakatikati sangakwanitse. Opaleshoniyo ndi yovuta, ndipo zamkati zomwe zimaperekedwa zimakhalabe zovuta kukwaniritsa miyezo yotulutsa.

Njira Yowonongera Zachilengedwe

Njira yowonongeka kwachilengedwe ndi njira yoyeretsera yomwe imawononga cyanide pogwiritsa ntchito zinthu zachilengedwe monga kuwala. Zimaphatikizapo zotsatira za cyanide volatilization, decomposition, oxidation, photochemical degradation, biodegradation, precipitation, and adsorption, zomwe zimakhala chifukwa cha zovuta zowonongeka za thupi, photochemistry, ndi biochemistry.

• ubwino: Njira yoyeretsera zachilengedwe imatha kukwaniritsa cholinga chochotsa cyanide popanda zida kapena mankhwala aliwonse, kotero mtengo wake ndi wotsika kwambiri.

• kuipa: Njirayi ndi yochedwa kwambiri, ndipo madzi otayira oyeretsedwa sangathe kukwaniritsa miyezo yotulutsidwa.

Awiri - Njira Yakugwetsa Kwamagawo

Njira ziwiri zoyambira mpweya ndi njira yotsekedwa bwino - kuzungulira kwathunthu - njira yozungulira yopangidwira zomera zazing'ono ndi zazing'ono - zazikulu zagolide za cyanidation zokhala ndi SCN⁻ madzi onyansa, omwe amatha kutulutsa "zero discharge" yamadzi onyansa. Njira ziwiri za mpweya wa siteji zimaphatikizapo kuwonjezera chothandizira ndi mpweya wokwanira ku cyanide m'madzi onyansa, ndiyeno kuchotsa cyanide kudzera muzotsatira zotsatirazi pa golide.

2Cu⁺ + 2SCN⁻→Cu₂(SCN)₂↓

Ca²⁺ + SO₄²⁻→CaSO₄↓

Pb²⁺ + SO₄²⁻→PbSO₄↓

H⁺ + CN⁻→HCN

• ubwino: Imatha kuchotsa ayoni azitsulo zolemera mu yankho ndikukwaniritsa kubwezeretsanso madzi oyipa.

• kuipa: Gawo loyamba la mvula liyenera kukhala lokwanira. Kupanda kutero, powonjezera alkali, cuprous rhodanate imasungunukanso, zomwe zikukhudza chithandizo. CaSO₄ yosawerengeka imatha kuyambitsa kutsekeka kwa ma valve.

Izi ndi njira zodziwika bwino zoyeretsera madzi a cyanide muzomera zagolide za cyanidation. Kuphatikiza pa cyanide yomwe ili pamwambapa - njira zochotsera, kuchepetsa kugwiritsa ntchito cyanide mu ndondomeko ya golide ya cyanidation kungathenso kuchepetsa kutuluka kwa madzi onyansa a cyanide.