THERMODYNAMIC MODEL OF PRODUCING FERTILIZERS FROM CHIPS OF CUTTED BRANCHES OF FRUIT TREES

Abstract

The article presents a thermodynamic model of the process of the bunch method of composting fruit tree chips, the essence of which is the general solution of the equations of heat balance and heat transfer. A scheme for determining heat loss in the process of composting wood chips, which consists of a cylindrical and hemispherical parts of the collar and a diagram of the heat transfer process in the cylindrical part of the collar in layers, from which it is clear that thermal reactions occur in the middle layer, is considered. The results of experimental studies on the determination of the specific energy loss components in the composting process are presented and the potential energy efficiency of the a bunch composting method is calculated, which amounted to 27,6%. Such composting efficiency can be achieved in a bunch with the following parameters: layer thickness from the soil surface 0,1 m, chip layer thickness 1,2 m, layer thickness from air 0.3 m, a bunch length 6,4 m and surface area 32,2 m². With such parameters, the bunch energy losses due to heat transfer to the environment do not exceed the calculated energy losses. At the same time, the optimum temperature regime is formed in the bunch layer where chip transformation processes take place: for mesophilic bacteria, the temperature is 27°C, and for thermophilic bacteria it is 50°C. It is proved that the specific amount of useful energy in the finished compost is 2,9 MJ/kg, and to reduce energy loss from chip heterogeneity and shorten composting time, the branches must be crushed to particles up to 10 mm long with the presence of longitudinal splitting, which increases its contact surface by 50-59%. It is noted that the implementation of the a bunch method of composting cod according to the given model will meet the requirements of the Global G.A.P. standard, namely: to promote the rational use of natural resources, minimize the risks of the spread of diseases and weeds, and increase soil fertility in gardens through the use of the obtained                        fertilizer.