The article gives the expert assessment data on the selection of the best ways of low-moisture peat harvesting by a milling method. They are essential to reducing the energy expenditure for the artificial drying of peat and ensuring the quality characteristics of raw material required for further thermochemical processing. The R&D efforts towards stimulation of the field drying of crumb peat are analyzed. The method of prioritization is applied in expert assessment. An appropriate significance rank value is assigned to each method. Mathematical estimate of the expert information reliability is made by the range and the variance of total ranks. The consistency of experts’ decisions on the assessment of the milled peat drying stimulation methods was checked by the relative range of significance values as well as the actual and the estimated strength of an expert group. Preference is given to two options: peat drying to harvesting humidity of 35% in thick layers and that on the slopes of pre-formed swaths of raw peat crumb.

The article presents two options of organizing the technological process of milled peat extraction with due consideration of weather conditions for peat drying. The first option of the technological process is the extraction based on cycle peat harvesting differentiation. The developed technological process of milled peat drying in thick layers based on pneumatic peat harvesting allows us to organize a technology of peat extraction with a constant cycle time, avoiding the necessity for drying rate prediction. This is due to the fact that under good weather conditions the spreading thickness of 45-50 mm is sufficient to maximize the number of harvesting cycles. Milling at roughly equal depths forms the basis for the second option of technological process. The article presents the methodology of calculating such technological parameters as cycle and seasonal harvesting, number of cycles and seasonal productivity of a harvesting machine. Seasonal harvesting and seasonal productivity of a harvesting machine are calculated by technological design standards. The analysis of calculations revealed that in the process of milled peat extraction based on cycle harvesting differentiation, it is necessary to apply coefficient 0.9 that takes into account the organization of harvesting machines operation.

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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.