Effectiveness of biomass-based fly ash in pulp and paper liquid waste treatment

Abstract

Adsorption is regarded as one of the most promising and straightforward strategies for reducing organic pollutants from wastewater effluents. The use of adsorbents from economical raw materials, even those from waste, is one recent concern. This study aims to test the effectiveness of biomass-based fly ash in treating liquid waste from pulp and paper production activities. Fly ash (FA) performance for adsorption was tested by varying the ratio of adsorbent with wastewater by 20, 40, 60, and 80 g/L. The adsorbents' performance was then compared between the application of FA directly (without activation) and adsorbents that were previously calcinated in 100 °C and 200 °C. Samples of pulp and paper liquid waste are placed on the erlenmeyer flask and stirred using a jar test with speeds varying by 100, 200, and 300 rpm. The results showed that FA is potential directly used with no thermal treatment as an adsorbent in treating liquid waste in the pulp and paper industry. It was effectively used with a dosage of 20 g/L and a 100 rpm fatigue speed with a contact time of 10 min. The quality changes of several wastewater parameters were found with a 92.5% reduction in TSS, 83.31% in COD, 19.99% in chlorides, 95.41% in NH3, and 19.6% in TDS, 19.6% in EC. Those parameters have successfully complied with the regulation standard of Indonesia (SNI) for wastewater.