COD ndi chizindikiro chomwe chimatanthawuza kuyeza kwa zomwe zili m'madzi.COD ikakwera, m'pamenenso kuipitsidwa kwambiri kwa madzi ndi zinthu zachilengedwe.Poizoni organic kanthu kulowa m'madzi thupi osati kuvulaza zamoyo m'madzi monga nsomba, komanso akhoza kulemeretsedwa mu unyolo chakudya ndiyeno kulowa thupi la munthu, kuchititsa aakulu poizoni.Mwachitsanzo, kupha kwa DDT kosatha kungawononge dongosolo lamanjenje, kuwononga ntchito ya chiwindi, kumayambitsa kusokonezeka kwa thupi, komanso kukhudza kubereka ndi majini, kutulutsa zowopsa komanso kuyambitsa khansa.
COD imakhudza kwambiri madzi komanso chilengedwe.Zowononga zachilengedwe zokhala ndi COD zokwezeka zikalowa m'mitsinje ndi m'nyanja, ngati sizingachiritsidwe munthawi yake, zinthu zambiri zamoyo zimatha kuyamwa ndi dothi lomwe lili pansi pamadzi ndikuwunjikana pakapita zaka.Zidzawononga zamoyo zamitundu yonse m'madzi, ndipo zotsatira zake zapoizoni zitha zaka zingapo.Poizoniyu ali ndi zotsatira ziwiri:
Kumbali imodzi, izi zipangitsa kufa kwambiri zamoyo zam'madzi, kuwononga chilengedwe m'madzi, komanso kuwononga mwachindunji chilengedwe chonse chamtsinje.
Kumbali ina, poizoni amawunjikana pang’onopang’ono m’matupi a zamoyo za m’madzi monga nsomba ndi shrimp.Anthu akamadya zamoyo zam'madzi zakuphazi, poizoni adzalowa m'thupi la munthu ndikuunjikana m'zaka zambiri, zomwe zimayambitsa khansa, kupunduka, kusintha kwa jini, etc. Zosayembekezereka zoopsa.
COD ikakwera, imayambitsa kuwonongeka kwa madzi amadzi achilengedwe.Chifukwa chake ndi chakuti kudziyeretsa kwa thupi lamadzi kumafunika kusokoneza zinthu izi.Kuwonongeka kwa COD kuyenera kudya mpweya, ndipo mphamvu ya reoxygenation m'madzi singathe kukwaniritsa zofunikira.Idzatsika mwachindunji ku 0 ndikukhala dziko la anaerobic.Mu chikhalidwe cha anaerobic, chidzapitirira kuwola (mankhwala a anaerobic a tizilombo toyambitsa matenda), ndipo thupi lamadzi lidzasanduka lakuda ndi lonunkhira (tizilombo ta anaerobic zimawoneka zakuda kwambiri ndikupanga mpweya wa hydrogen sulfide. ).
Kugwiritsa ntchito zowunikira zam'manja za COD kumatha kupewa kuchulukirachulukira kwa COD mumtundu wamadzi.
Chowunikira cha COD chonyamula chimagwiritsidwa ntchito kwambiri pozindikira madzi apamtunda, madzi apansi panthaka, zimbudzi zapanyumba ndi madzi otayira m'mafakitale.Sikoyenera kokha kuyesedwa kwadzidzidzi kwadzidzidzi kumunda komanso komwe kuli pamalopo, komanso kusanthula kwamadzi kwa labotale.
Miyezo yogwirizana
HJ/T 399-2007 Ubwino wa Madzi - Kutsimikiza kwa Kufunika kwa Chemical Oxygen - Rapid Digestion Spectrophotometry
JJG975-2002 Chemical Oxygen Demand (COD) Meter
Nthawi yotumiza: Apr-13-2023
