Recovery of phosphorus from actual small-scale food establishment wastewater through the precipitation process

Abstract

An essential nutrient that regulates growth is phosphorus. Excess phosphorus in the bodies of water causes eutrophication and impairs the quality of water resources. The supply of phosphorus is projected to be depleted in the next century since it is from non-sustainable mineral deposits. Phosphorus is extracted by the weathering of rock naturally and by the process called strip mining. One of the alternatives to sustain the phosphorus resources is to recover the phosphorus in wastewater. The study aimed to remove and recover the phosphate from SSFE wastewater by chemical precipitation. The phosphates from food establishment wastewater were successfully removed and recovered by the precipitation process using magnesium chloride as precipitant, the form of phosphorus recovered is a phosphate compound. Different SSFE wastewaters were gathered from different locations. The average removal efficiency of phosphate from SSFE 1 is 67.11 ± 0.22 % while the efficiency from SSFE 2 is 64.96 ± 0.62 % and from SSFE 3, the removal efficiency of 68.62 ± 0.48 % was obtained. The percent removal efficiencies of the three small-scale food establishment wastewater sources have no significant difference which means that the variations from the three sources of wastewater are not far from each other. The quality of the wastewater in terms of pH, DO, and phosphate content has been improved while the TDS slightly increased. Data obtained indicates that chemical precipitation can remove and recover phosphorus from SSFE wastewater. This study serves as a smart step for many food establishments to begin treating their wastewater with an alternative, inexpensive, and simple method.