Abstract:
The feasibility of using zeolite industrial wastewater (ZIW) as a sorbent and/or
precipitant in removing Cu, Zn, and other pollutants in copper-brass pipe industrial
wastewater (CIW) was investigated. The ZIW and CIW were sampled and determined
for pH, Temperature, Biochemical Oxygen Demand (BOD5), Chemical Oxygen
Demand (COD), Total solids (TS), Total dissolved solids (TDS), Total suspended
solids (TSS) and heavy metals. Sorption isotherms of Cu and Zn in CIW onto solid of
ZIW at various dilutions of CIW were explored. The relationship between Cu and Zn
concentrations and their removal efficiencies under different conditions of wastewater
pH, contact times, and ratios of CIW to ZIW was examined. Optimum treatment
condition was selected and used for observation of their influence on the efficiency of
treatment of other pollutants.
ZIW contained various carbonate compounds which contributed to high pH
and TDS values, and low heavy metals contamination whereas CIW had low pH value
and was enriched with heavy metals especially Cu and Zn. Application of ZIW
significantly increased the pH of CIW and remove heavy metals. The higher pH of the
mixture enhanced metal removal. The Langmuir equation described sorption
isotherms of heavy metals by solid of ZIW at neutral pH (6-7) while the Freundlich
equation did well at pH values over12. The maximum Cu (97-98%) and Zn (92-96%)
removal efficiencies occurred at non-adjusted pH condition (12.8) of ZIW, ratio of
CIW to ZIW 3:1 (vol.:vol.) and 30 minutes of contact time. The efficiency of
treatment under these treatment conditions of the pollutants, COD, TS, TDS and TSS
was 40%, 2%, 2% and 23%, respectively.
Further study should put an emphasis on increasing the treatment efficiency of
TS and TDS. The economic feasibility of using ZIW should also be reviewed together
with other significant circumstances.