Development of Peat Processing Methods for Production of Innovative Products

Abstract

Synthesis or humification of humic substances (HSs) is the second widely applied organic compound transformation process after photosynthesis. Peat decomposition process results in a production of a HSs which has a high demand in agriculture, forestry, and gardening areas. Addition of the KOH is good option for environmental protection and K+ belongs to the nitrogen, potassium and phosphorous (NKP) mineral component. A homogenization process in a customize for commerce, where peat treatment technology was improved with the help of the cavitation effect. This effect was provided with the help of the high-speed mixer-disperser (HSMD) developed at Riga Technical University. Mechanical cavitation causes relatively high energy shifts from mechanical movement of cavitation causing elements to the liquid medium which causes efficient destruction of particles inside a suspension. Values of the peat particle diameter at 50 % in the cumulative distribution before and after 1, 2, and 3 homogenization cycles were measured in the present study. The aim of the present study was to find the optimal conditions (KOH concentration, cavitation cycles and reaction temperature) to produce potassium humate (K-HSs) regarding sustainable regenerative approach aspects. Cavitation treatment of the tested peat particle diameter at 50 % in the cumulative distribution (d50) from 267 down to 129 µm; the peak in the size range from 160 up to 409 µm completely disappears and significantly decreases the number of Dalton’s which causes the more efficient formation of fulvic acid caused by increased concentration of carbonyl and carboxyl groups as compared with the conventional homogenization method.