Edris Bazrafshan, Ferdos Kord Mostafapour, Mahdi Farzadkia, Kamaledin Ownagh, Hossein Jaafari Mansurian,
Volume 5, Issue 3 (10-2012)
Abstract
Background and Objectives: Slaughterhouse wastewater contains various and high amounts of organic
matter (e.g., proteins, blood, fat, and lard). In order to produce an effluent
suitable for stream discharge, chemical coagulation and electrocoagulation
techniques have been particularly explored at the laboratory pilot scale for
organic compounds removal from slaughterhouse effluent. The purpose of this
work was to investigate the feasibility of treating cattle-slaughterhouse
wastewater by combined chemical coagulation and electrocoagulation process to
achieve the required standards.
Materials and Methods:
At present study, slaughterhouse wastewater after initial analysis was tested
for survey of coagulation process using Poly aluminum chloride (PAC) at various
doses (25-100 mg/L). Then we measured the concentrations of wastewater
pollutants (BOD5, COD, TKN, TSS and fecal Coliforms). Later, we transferred the
effluent to the electrocoagulation unit and we evaluated the removal efficiency
of pollutants in the range 10 to 40 volts of electric potential during 60 min.
Results: It was found
that the efficiency of chemical coagulation process using poly-aluminum
chloride (PAC) as coagulant increases with increasing doses (from 25 to 100
mg/L) we achieved maximum removal efficiency during the chemical coagulation
for parameters of BOD5, COD, TSS, and TKN at 100 mg/L of PAC equivalent to
44.78%, 58.52%, 59.9%, and 39.58% respectively. Moreover, the results showed
that with increasing the electric potential and reaction time, the yield
increases linearly so that maximum removal efficiency at a dose of 100 mg/L
PAC, an electrical potential of 40 volts and a reaction time of 60 minutes for
the parameters BOD5, COD, TSS, and TKN was 99.18% 99.25%, 82.55%,
and 93.97% respectively.
Conclusion: The
experiments demonstrated the effectiveness of combined chemical coagulation and
electrocoagulation processes for pollutants removal from the slaughterhouse
wastewaters. Consequently, this combined process can produce effluent
compliance with the effluent discharge standards.
Sh Goodarzi, Gh Shams Khoramabadi, M Esmaty, Ma Karami, A Hossein Panahi,
Volume 12, Issue 2 (9-2019)
Abstract
Background and Objective: Wastewater from pharmaceutical industry has high chemical oxygen demand as a result of the presence of organic drugs and antibiotics. In order to meet the environmental requirements, several treatment methods like chemical and electrochemical methods have been widely applied due to their high ability to remove organic compounds from pharmaceutical wastewater. Therefore, the present study aimed to evaluate the efficiency of chemical coagulation/Electro-Fenton treatment method to degrade the organic matter-containing pharmaceutical industry wastewater.
Materials and Methods: The experimental tests were carried out using batch mode. The chemical coagulation process was evaluated as a function of aluminum chloride concentration (25-300 mg/L) and pH (3-10). The effluent from chemical coagulation process was transferred to Electro-Fenton reactor. Effects of H2O2 concentration (100-4000 mg/L), reaction time (up to 120 min), voltage (10-30 V), and pH (3-10) were evaluated. The removal efficiency was determined in term of COD removal.
Results: The results showed that the highest removal of COD in the chemical coagulation was 49% (coagulant dose of 200 mg/L, and pH of 7). In addition, the Electro-Fenton process could be eliminating of 93.5% of COD at the optimum conditions concentration (100 mg/L H2O2, voltage of 20, pH of 3, and contact time of 30 min).
Conclusion: According to the results, it can be concluded that the combination of chemical and electrochemical processes was found to be effective methods for treatment of pharmaceutical wastewater in comparison to the application of each process separately. To reach to the maximum removal efficiency, the environmental parameters should be carefully controlled at their optimum values in each single process.
