treatment, wastewater, bleach, ion exchange, electrochemically generated reagent
Abstract
The processing of food processing waste in the form of highly concentrated solutions of sodium salts, sulphates and phosphates generated from the acid refining of vegetable oils is of great importance. Acidic effluent, which refers to liquid waste from vegetable oil refining, can be described as a concentrated multicomponent solution of impurities of organic and inorganic origin. The salt state of the main substance (35 g of Na2SO4) can be described in terms of the molecular concentration of the component as follows: 0.2 mol SO4-, 0.5 mol Na+. Thus, this solution can be classified as highly concentrated, characterised by strong intercomponent interaction. Therefore, itshould be assumed that the technology of sulphate purification is associated with a change in the state and concentration of other components and should include elements of organic impurities removal. Thus, we studied individual processes in the elements of the multistage process of this wastewater treatment, which includes: pretreatment (including organic impurities), ionic desalination, desalination (crystallisation) of concentrates after ionic desalination, processing of concentrates to extract reagents.To solve the problem of industrial wastewater treatment in the form of liquid waste from organic compounds for the possibility of its further biological treatment, the use of chlorine lime as an oxidising agent and coagulant is proposed at the pre-treatment stage. After sedimentation, the subsequent removal of suspended solids and residual active chlorine takes place on a multilayer filter.The filter is loaded with ferrous chips, granite and sand. The resulting ferric hydroxide also serves as an additional coagulant. There is a need to recycle (desalinate) solutions of well-dissolved salts formed during the regeneration of ionites at the stage of ion exchange. The possibility of removing sulphates from solutions in the form of insoluble calcium sulphate salt was studied. The problem of processing regeneration solutions of ionites to obtain electrochemically generated reagents (oxidants) for use at the pretreatment stage to reduce the consumption of chlorine lime was solved. This made it possible to reduce the organic load of treated wastewater by COD by 87%.
Author Biographies
N. M. Korchyk, National University of Water and Environmental Engineering
Candidate of Engineering (Ph.D.), Associate Professor
O. P. Romanenko, National University of Water and Environmental Engineering
