Application of excess sludge extract from sewage treatment plant in garden flower planting

Abstract

In order to explore the application effect of excess sludge extract from sewage treatment plant in garden flower planting, the extracts prepared from excess sludge and its fertilizer efficiency were evaluated and its effects on plant height, stem diameter, flower yield and diameter and plant weight of Impatiens balsamina were studied by pot experiments, which provided reference for the resource utilization of excess sludge. The results showed that the initial solution content of amino acid in excess sludge extract was 3.6%, and the total amount of microelement was 66.46 ppm. It was fully soluble, slightly alkaline, and the harmful elements As, Cd, and Pb did not exceed the content of the standard. Although the total amount of amino acids and microelement was lower than the standards of amino acid-containing foliar fertilizers in China, it can meet the requirement of foliar fertilizer dilution in the market and can be used as amino acid foliar fertilizer after dilution. The appropriate concentration of excess sludge extract can promote the growth of Impatiens balsamina significantly, and the application effect was close to or better than some foliar fertilizer products in the market. The best concentration was 600 times diluted excess sludge extract. If the excess sludge extract is further prepared into amino acid foliar fertilizer, the effect will be better, it can be applied in garden flower planting, and can provide a new way for the resource utilization of excess sludge in sewage treatment plant.