HYDRO-JET METHOD FOR SCOTS PINE NEEDLE SEPARATION FOR INTEGRATED PROCESSING

Abstract

The article presents a novel approach to the separation of Scots pine (Pinus sylvestris) needles from branches using a hydraulic jet, which ensures the preservation of needle structure for further integrated processing. The relevance of the study is driven by the need to utilize forestry by-products, particularly pine needles, as a source of biologically active compounds, essential oils, extracts, and cellulose-containing raw materials for the production of natural textile fibers.

A conceptual design of the unit has been developed, combining the processes of jet formation, branch feeding, needle separation, and collection. The proposed unit can be implemented in both mobile and stationary configurations, making it adaptable to various logging conditions.

Based on hydrodynamic analysis, the relationship between the key parameters—pressure before the nozzle, fluid flow rate, nozzle diameter, and the distance to the target—has been established. A theoretical model was constructed to calculate the minimum pressure required for effective needle detachment, taking into account gravitational acceleration and turbulent jet expansion. It was shown that the most efficient action zone is located within the compact part of the jet.

The hydro-jet method offers several advantages, including high process speed, simultaneous cleaning of the needles, energy efficiency, and structural simplicity. The technology aligns well with the principles of sustainable natural resource management and can become an effective component in the zero-waste processing chain of coniferous biomass.