Making of KCl liquid fertilizer from liquid waste manufacture of seaweed and galvanized industry

Abstract

The seaweed processing industry uses potassium hydroxide (KOH) in the seaweed cooking process, while the galvanized industry uses hydrogen chloride (HCl) in the pickling process. Liquid waste from these two types of industries can cause environmental pollution if not managed properly. This study aims to utilize liquid waste from the seaweed processing industry and galvanized industry into KCl liquid fertilizer as an effort to manage the environment while providing economic value for waste. The quality of liquid waste from the seaweed processing industry, liquid waste from the galvanized industry, KCl liquid fertilizer and the content of heavy metals in fertilizer are analyzed through experimental testing using SNI and AOAC methods. The results showed that liquid waste from the seaweed processing industry can be utilized together with liquid waste from the galvanized industry to produce KCl liquid fertilizer that meets the requirements of SNI 02-2805: 2005 and Minister of Agriculture Regulation Number 43 / Permentan / SR.140 / 8 / 2011. Potassium levels as K2O from KCl liquid fertilizer produced ranged from 727 - 16443 ppm, where the value is higher than the standard according to SNI 02-2805: 2005 of 600 ppm. The content of heavy metals in liquid fertilizer produced meets the requirements of the Minister of Agriculture Regulation No. 43 / Permentan / SR.140 / 8/2011. Consequently the range of heavy metals contained in liquid fertilizer produced by As, Hg, Cd, and Pb is 0.0032 - 0.034 ppm, 0 - 0.0007 ppm, 0.0064 -0.0546 ppm, and 0.0006 - 0.3497 ppm, where the values This is lower than the standard according to Regulation of the Minister of Agriculture No. 43 / Permentan / SR.140 / 8/2011 namely As (max 100 ppm), Hg (max 10 ppm), Cd (max 100 ppm), and Pb (max 500 ppm).