A commercially available ASPEN PLUS simulation using a pipe model was employed to determine the maximum safe pipeline distances to subsequent booster stations as a function of carbon dioxide (CO₂) inlet pressure, ambient temperature and ground level heat flux parameters under three conditions: isothermal, adiabatic and with account of heat transfer. In the paper, the CO₂ working area was assumed to be either in the liquid or in the supercritical state and results for these two states were compared. The following power station data were used: a 900 MW pulverized coal-fired power plant with 90% of CO₂ recovered (156.43 kg/s) and the monothanolamine absorption method for separating CO₂ from flue gases. The results show that a subcooled liquid transport maximizes energy efficiency and minimizes the cost of CO₂ transport over long distances under isothermal, adiabatic and heat transfer conditions. After CO₂ is compressed and boosted to above 9 MPa, its temperature is usually higher than ambient temperature. The thermal insulation layer slows down the CO₂ temperature decrease process, increasing the pressure drop in the pipeline. Therefore in Poland, considering the atmospheric conditions, the thermal insulation layer should not be laid on the external surface of the pipeline.

Thermodynamic and economic analysis of a 900 MW ultra-supercritical power unit: The paper presents a thermal-economic analysis of different variants of a hard coal-fired 900 MW ultra-supercritical power unit. The aim of the study was to determine the effect of the parameters of live and reheated steam on the basic thermodynamic and economic indices of the thermal cycle. The subject of the study was the cycle configuration proposed as the "initial thermal cycle structure" during the completion of the project "Advanced Technologies for Energy Generation" with the live and reheated steam parameters of 650/670 °C. At the same time, a new concept of a thermal cycle for ultra-supercritical parameters with live and reheated steam temperature of 700/720 °C was suggested. The analysis of the ultra-supercritical unit concerned a variant with a single and double steam reheat. All solutions presented in the paper were subject to a detailed thermodynamic analysis, as well as an economic one which also included CO₂emissions charges. The conducted economic analysis made it possible to determine the maximum value of investment expenditures at which given solutions are profitable.