Replacement of Chemical Fertilizer by Beverage Sludge to Reduce Environmental Pollution
Abstract Wastewater generation from beverage industries is on the rise as the demand and consumption surge worldwide. The typical ingredients of beverages are carbonated water, saccharides, sweetener, fruit pulp, flavoring agent, color, preservatives, and salts. Only 20% concentration of the mixture goes to the bottle and the remaining becomes wastewater. However, nutrients and organics remain in wastewater and are left in sludge after going through ETP. The presence of these nutrients makes the beverage sludge useful for the cultivation that can not only decrease the application of chemical fertilizers but also combat the environmental pollution. Indian spinach and Okra have been cultivated in six different mixtures containing beverage sludge and soil to study their effects on growth, yield, food value and nutrient. Soil nutrients, organic content, EC, and pH have been analyzed to assess the suitability of sludge for cultivation. The control treatment was designed by 100% soil and gradually 20, 40, 60, 80 and 100% soil were replaced by beverage sludge in other treatments. The maximum growth of Indian Spinach and Okra was observed 120% and 125% higher at 38 days after sowing on the treatment of 80% sludge and 20% soil compared to the control treatment. Similarly, the maximum yield of Indian spinach and Okra was computed to be nine and two times higher than the control on the same treatment. Food values (ascorbic acid, β- carotene, and protein) and nutrients (Fe, Ca, Mg, K, P and Zn) were found to increase with the increasing amount of beverage sludge while those satisfy the standards of USDA. Without using any kind of fertilizer in low grade soil, the beverage sludge has shown the potentiality in both growth and yield. It turns out that beverage sludge can be used as a substitute for chemical fertilizer with an optimum amount of 80%.