Paper industry wastewater treatment by electrocoagulation and aspect of sludge management

The paper production process comprises various manufacturing steps and generates an enormous amount of effluent, which consists of a large variety of contaminated chemicals. The higher color and chemical oxygen demand (COD) of the wastewater create a negative effect on all living forms and the natural environment. Electrocoagulation is a versatile process for the elimination of color and COD content from wastewater. In this study, the EC treatment has been used to identify the ideal conditions using several process variables such as pH, current density, time, and the dose of electrolyte. COD and color were reduced by up to 68% and 94%, respectively. Afterward, the treated water was compared with the standards of the world health organization (WHO) and the central pollution control board (CPCB) to find out the suitability of treated water for reuse for farming purposes. Germination tests of mung beans were conducted, and it was observed that the EC treated water is suitable for irrigation. The corrosion rate of mild steel was determined to be 2.85 mils/year, which has shown the short life span of mild steel electrodes. Furthermore, sludge produced by the EC process was analyzed and characterized for physicochemical analyses by using a variety of analytical techniques. The 69.93% iron content of the sludge was also recovered using the acid digestion method. After the physicochemical analyses, it was observed that sludge could also be utilized as a compelling supplement for plant growth, energy recovery, and industrial applications. According to this study, treated water could be a powerful alternative for reducing freshwater consumption in agricultural areas and increasing water availability in water-scarce areas.

Automated summary

In this study, electrocoagulation was used to treat paper production wastewater and reduce COD and color content. The treated water was found to be suitable for irrigation based on germination tests. Furthermore, the produced sludge was analyzed and found to have potential applications in plant growth, energy recovery, and industry.