Treatment of palm oil mill effluent using electrocoagulation powered by direct photovoltaic solar system

High commercial electricity consumption is one of the disadvantages in the operation of lengthy electrocoagulation processes. To cater to this problem, this study develops an integrated photovoltaic-electrocoagulation system in treating oil palm mill effluent (POME). This system has successfully reduced 23,837 mg/L of chemical oxygen demand (COD) and 15,153 mg/L of biological oxygen demand (BOD) in 8 h. It was found that the higher solar radiation harvested by photovoltaics produces a higher current intensity, which in turn generates more in-situ coagulants into the wastewater. This relates to COD and BOD removal's significance from 150 to 390 min, where the current intensities are in the maximum range (between 153–181 mA). The first-order kinetic models of COD and BOD are in good correlation coefficient, which is 0.9873 and 0.9837, respectively. Overall, this study findings recommend the possibility of sustainable operation in the actual wastewater pond

Treatment of palm oil mill effluent by electrocoagulation with presence of hydrogen peroxide as oxidizing agent and polialuminum chloride as coagulant-aid

The purposes of this study were to investigate the effects of operating parameters, such as electrode material, current density, percentage of hydrogen peroxide and amount of polialuminum chloride (PAC) on chemical oxygen demand (COD) removal of palm oil mill effluent (POME). The current density was varied between 30–80 mA cm−2, PAC (1–3 g L−1) as coagulant-aid and 1 and 2% of hydrogen peroxide as an oxidizing agent. As for the performance of electrode type, iron was more effective than aluminum. It appeared that the removal of COD increased with the increased of current density. When PAC and H2O2 increased, the percent of COD removal was increasing as well. The overall results demonstrate that electrocoagulation is very efficient and able to achieve more than 70% COD removal in 180 min at current density 30–80 mA cm−2 reliant upon the concentration of H2O2 and PAC

Application and challenges of membrane in surface water treatment

Herein, we reviewed NOM and its components as the major membrane foulants during the separation and purification of water works. In addition, possible fouling mechanisms relating to NOM fouling, current techniques employed to characterize fouling mechanisms and methods to control fouling were briefly discussed. Conventional water treatment which involves a train of operating units such as coagulation, flocculation and sand filtration consumes substantial spaces and high Hydraulic Retention Time (HRT). Besides that it relies most on chemical consumption such as aluminium sulphate, ferric chloride and poly-aluminium chloride which end up as sludge waste contaminated with aluminium or ferric oxides. Furthermore, the chemical reaction between Natural Organic Matter (NOM) and disinfectant agent such as chlorine or chloramines has been extensively reported to form carcinogenic Disinfection By-Product (DBPs) which is potential in causing deleterious cancers diseases. Therefore, a more reliable and greener technology such as membrane technology has been employed as it possesses better capability in producing water of exceptional quality and practicality over the conventional treatment process. However, the widespread of this potential feature is significantly restricted by fouling issue which reduces its productivity, permeate quality and treatment performance