COMPARATIVE ANALYSIS OF CERTAIN TECHNICAL, TECHNOLOGICAL AND ENVIRONMENTAL PARAMETERS OF EXPOSED REINFORCED CONCRETE LAGOONS FOR LIQUID CATTLE MANURE

V. Dimova, K. Peichev, D. Georgiev

Abstract: The aim of the present study was to provide a comparative analysis on some technical and environmental indicators for a variant of a “lagoon” fertilizer storage facility for liquid manure from a cow farm with a capacity of up to 150 dairy cows. Three variants of an open-pit reinforced concrete lagoon with the same volume (1303.6 m3) and depth (4.00 m) were developed: a rectangular lagoon and vertical walls; a rectangular lagoon and sloping walls and a lagoon with a round outline. It was found that the largest manure contact area and supposedly the highest level of emissions was the rectangular lagoon with sloping walls (387.6 m2). The area is about 19% larger than the round lagoon (325.9 m2) and the rectangular lagoon with vertical walls (326.4 m2). All the developed options are applicable for storage of liquid manure from the farm with small differences in the relative costs of reinforcing steel (5.5 - 6.8%), profile steel (1.2 - 4.9%) and concrete (3.4%). The most economical in terms of cost of building materials are the round lagoon and the rectangular lagoon with sloping walls. In event of compromising the insulation membrane, the smallest risk of soil contamination exists in the rectangular lagoon with sloping walls, with a total area of 603.1 m2. The risk increases by 3.7% in the round lagoon (625.6 m2) and by 14.8% in the rectangular lagoon with vertical walls (692.5 m2). In view of the small differences in the cost of materials for the construction of dug-out reinforced concrete lagoons with different outlines and the severity of their ecological impact (release of emissions through the contact area “manure-air”), it is advisable to store liquid manure in free-box farming farms of a basic herd of up to 150 dairy cows to use a round lagoon.

Keywords: dairy free-stall; lagoon-type manure storages from reinforced concrete; liquid manure; technical, technological and environmental parameters

Date published: 2019-03-21