The Effect of Neutralising Materials on the Reaction of the Peat Substrate Medium when Growing Ball-Rooted Seedlings

The use of various types of neutralising materials in the cultivation of standard planting material of high-quality forest wood species has a significant effect on substrate acidity. Therefore, the study sets a goal to select peat substrates with different dosages of the neutralising component and determine their effect on the reaction of the peat substrate medium. The paper presents the results of the influence of neutralising materials of dolomitic meal and chalk of various doses with the use of mineral fertilisers. Dolomitic meal was used as a neutralising component, the pH of the peat substrate was 6.6 and chalk was 7.5. It was found that when neutralising a peat substrate created based on high-moor milled peat (pH 2.5) with the introduction of dolomitic meal in doses of 2-4 kg/m3 (European spruce), 3-4. 5 kg/m3 (Scots pine), optimal acidity can be achieved in a month. An increase in the concentration of lime material was recorded, which leads to an increase in the neutralisation of the substrate at a dose of 2.5 g and 3.0 g per 125 g of peat. The best indicators were demonstrated by options of doses of 1.5-2.5 g per 125 g of peat for 7-8 days of use and a dose of 3.0 g per 125 g of peat for 5-6 days compared with the control. An increase in the concentration of chalk in the neutralising material from 30% to 70% leads to a faster deoxidation of the substrate (pH 3.2), and an increase in the dosage of chalk increases substrate neutralisation. The electrical conductivity of the substrate at a dosage of 6-8 kg/m3 when applying chalk and dolomitic meal increases by 1.6-2.0 and 1.2-1.4 times, respectively. At the rate of application of 6-10 kg/m3, it has a lesser effect on the change in the electrical conductivity of the high-moor peat, and the introduction of dolomitic meal 2-4.5 kg/m3 into the milled peat during neutralisation does not lead to a change in the electrical conductivity of the peat. This data allows choosing neutralising materials of a certain concentration that will enable the cultivation of standard planting material of European quality and thereby ensure the proper quality of future stands

Economic Assessment of Low Humidity Peat Production Practice

The article presents a milled peat production practice based on deep bed drying up to a harvesting moisture content of 35%. The task of the developed technology is to minimize and stabilize the harvesting humidity in the field drying of peat, thereby reducing the time and thermal impact on the peat organic matter during a forced finish drying. The applied method of peat extraction provides for variable milling depth and differentiation of cycle harvesting to increase the number of cycles and the harvester seasonal output. An economic feasibility study has been carried out by the method of determining the operating costs per ton of a marketable product for each technological operation. It consists in a comparative assessment of two technological processes: the production practice based on intensification of milled peat drying up to a harvesting moisture content of 35% and the conventional harvesting of milled peat with moisture content of 45%. The developed technology of milled peat extraction makes it possible to ensure the required quality parameters in terms of humidity (≤ 35%) and to preserve natural bituminous components. Based on the economic assessment results, it has been found that there is a slight increase in operating costs per ton of a marketable product in comparison with the conventional practice.

Peat Storage Losses Investigation

The paper investigates the effect of self-heating, wetting and freezing of different milled peat types on field storage losses. It has been found that the loss of organic matter in peat due to self-heating depends on peat decay degree, type of product obtained, heating temperature (storage duration), preventive measures taken and the technological scheme of peat extraction. When such preventive measures as moving stacks, internal sealing and compaction of peat are taken, a decrease in self-heating and spontaneous combustion losses is observed. In two-stage harvesting, these losses are lower because of peat compaction in stacking operations. It has been established that there is a dependence of peat losses on its wetting and freezing, storage duration, and the total amount of precipitation accumulated over a certain period. With an increase in peat decay degree, the maximum wetting and freezing losses are several times lower than self-heating losses. These losses are 20% higher for upland peat than for lowland peat.

Influence of operating conditions of milled peat jet transport on relative sliding of air and solid phases

Air-and-peat mixture in horizontal jet transport pipeline is considered as a compressible two-component mixture with uniform distribution of solid peat particles in continuous air phase. Such heterogeneous medium flow is substituted for a flow of interpenetrating air phase and a quasi-solid phase approximating the flow of discrete particles. Such approach makes it possible to write individual equations of continuity and motion for each phase, but it is required to introduce the forces of aerodynamic interference at the phase boundaries in the motion equations. From the analysis of the known theoretical and experimental research data on jet transport of granular materials, it is possible to identify some parameters such that variation of any of these parameters changes the jet transport energy consumption. Such parameters are: jet capacity per mass of air and solid, Qair and Qs (kg/s) or input-output characteristic of mass concentration, μ = Qs/Qair; reduced velocities of air, Vair, solid particles, Vs, and soaring, Vsn, hereinafter called the flow-rate mode parameters, as well as the size and density of solid particles and the profile of the jet pipeline route. The flow-rate mode parameters are simply registered in the jet transport tests. The numerical determination procedure of the actual operating conditions of milled peat jet transport is justified. The known experimental data on jet transport of milled and treated peat are processed. It is found that the relative sliding ratio is functionally connected with all operating conditions in horizontal jet transport. The change of any parameter or their combination induces transition to air-and-peat mixture flow with various relative sliding of air and solid phases at different energy consumption of horizontal jet transport.

Influence of humic fertilizers on growth and biochemical parameters of lettuce plants

Humic fertilizers (HF) are a separate group of organic fertilizers, which include humic acids (HA), fulvic acids (FA), their salts, as well as some mineral componenrs. They combine the beneficial properties of macro- and microelements, adaptogens, biofungicides, plant growth stimulants. The aim was to study the effect of the introduction of a humic preparation obtained from peat into the soil and fertilizers “Sotka Potassium Humate” (Sotka) on the growth and biochemical parameters of lettuce plants. In the course of the work, a humic preparation was obtained from milled peat of the production site “Gorokhovsky” (Kotelnichsky district of the Kirov region) of the branch of VyatkaTorf JSC by the method of leaching of humic substances (HS). The HS content in the obtained preparation was 23.4% (18.6% HA and 4.8% FA). It was found that the humic preparation from peat had a greater effect on the accumulation of pigments by plants than the Sotka HF. The effect was especially pronounced with a single application of the drug to the soil; over time, this effect decreased. The effect of using Sotka fertilizer was manifested when it was applied as a top dressing on the 30th day after planting the seeds. Based on the results of the study, a series of photosynthetic pigments in descending order of HFs effect on their accumulation has been constructed: chlorophyll a > chlorophyll b > carotenoids. Along with the accumulation of pigments, the introduction of HF into the soil led to an increase in growth parameters and lipid peroxidation in lettuce leaves, which indicates a greater intensity of biochemical processes occurring in plants under the influence of HS.

STUDY OF THE OPERATION OF THE SUCTION NOZZLE OF PEAT PNEUMATIC HARVESTER

The extraction of milled peat by the pneumatic harvesting complex of machines has a number of advantages in contrast to the mechanical method. These advantages are as follows: the milling of wet peat deposits during harvesting is excluded, the range of required equi-pment is reduced, and the cycle time is shortened from two to one day. The latter is especially important, since two-day periods with good sunny weather in the production season are much less than one-day ones. Therefore, in general, the reliability of the method with pneumatic peat harvesting is higher. To evaluate the efficiency of the modern KTT-2 pneumatic harvesting machine, a field experiment was conducted to evaluate the suction speed of the nozzle of the machine. The results of the study made it possible to build the velocity field of the suction torch and determine the maximum suction speed – 26.74 m/s. The minimum air flow velocity in the studied zone is 0.3 m/s and is observed at a distance of 0.5 m from the nozzle. An analysis of the velocity field of the suction torch revealed the dependence of the air flow velocity on the distance from the nozzle. The size of the active zone of the suction plume has been identified and ways to optimize its size have been proposed.

Evaluation of KTT-2 Pneumatic Peat Harvesting Machine’s Nozzle Suction Capacity

Milled peat harvesting with pneumatic harvesting machines has a number of doubtless advantages over mechanical harvesting: operating time decreases down to 1 day, additional milling of wet peat deposit during the harvesting is not needed, list of necessary machinery decreases. However, in the late 1980s, due to the imperfection of the design of pneumatic machines, this method began to be used less and less frequently. Market appearance of KTT-2 and MPTU-30 pneumatic harvesting machines promoted their introduction into operating processes of peat extractive companies. According to feedback from operators, these machines work well with high-moor peat but work much worse with low- moor peat which is of higher density. One of basic parameters of pneumatic harvesting is suction velocity, that’s why field experiment for evaluation of KTT-2 machine suction nozzle performance was held. Experiment results enabled us to plot velocity diagram of suction flow and find maximum suction velocity: 26.74 m/s. Velocity diagram analysis showed distance from the nozzle – air flow speed relation. We calculated size of suction flow’s active area and offered methods of active area sizing.

Improved Calculation Methodology for Cycle Harvesting of Milled Peat

The article presents the calculation methods for cycle harvesting of milled peat. They are recommended for the three flow sheets of milled peat production: (a) a method based on a mechanical extraction by means of tanker harvesters; (b) a separate method of peat harvesting and transporting to large stacks and (c) a method based on pneumatic peat harvesting. Positive and negative aspects of the given methods are described and the improved calculation methods for cycle harvesting of milled peat are offered. The proposed methods take into account the weather conditions of a peat production region, the decrease in the initial moisture in the second and subsequent cycles after precipitation, due to the loss of fragmented peat from the previous cycle. A drying rate reduction factor is introduced into calculations in view of the uneven spread of milled crumbs. The performed calculations show that the reduced to 15% cycle harvests are possible to use in a design in comparison with those calculated by the previous technical design standards.