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Many organisations consider environmentally friendly activities, including the reduction of their carbon footprint, to be a significant aspect of their operation. In this study, a mathematical model was used to calculate the carbon footprint of food products at different stages of internal transport, using data on internal transport energy consumption. It was shown that for most products, the highest carbon footprint was related to the raw material transport stage from the loading/unloading point to the workstations on the production line. Broccoli showed the highest carbon footprint for internal transport per tonne of raw material. The study proposes methods of reducing the internal transport-related carbon footprint, which involves reorganising the distribution of goods in the warehouse and using nutritionally valuable vegetable waste in the production of food products.

Current legal regulations concerning ozone-depleting substances and greenhouse gases result in a dynamic return to the use of natural refrigerants such as hydrocarbons. However, they are gases included in the A3 (combustible) security group, and that is why they are now mainly used in devices with low performance (mainly in household refrigerators). The most widely used hydrocarbon as a refrigerant in this group of devices is R600a (isobutene). The article presents a comparative assessment of the lubricity properties of oil-refrigerant mixtures of three mineral oils with R600a. The assessment was based on a sample wear volume of the block-on-ring node under the conditions approximating the operation of the compressor after an extensive standstill period. The oil/refrigerant mixture was obtained as a result of an appropriately extended mutual contact of both substances in a closed chamber.

Friction nodes in refrigeration compressors are lubricated with a mixture of lubricating oil and refrigerant. The concentration of refrigerant in oil depends on temperature and pressure of the refrigerant. Determining the effect of this mixture on the size of wear in refrigeration compressors in laboratory conditions is only possible through an accurate reflection of friction parameters.The authors managed to prepare a prototype stand for a tribological test with a model block-on-ring friction node and the high-pressure chamber allowing for simulated conditions in refrigeration compressors. The present paper includes the description of the experimental method and procedure of model wear test of refrigeration compressors parts. The study itself constitutes the basis for the verification tests of the stand.