This paper describes experiments on the application of sodium bicarbonate desulphurisation in the coal-fuel boiler. The boiler has been in operation for several years now and it has refiably fulfilled the original assignment to reduce SO2 emissions from the value of 1200 - 1500 mg/Nm3 to 400 mg/Nm3. Higher desulphurisation efficiency is determined only by the ratio of Na/S sorbent dosage. The resulting product of desulphurisation is stored together with fly ash in underground mines, and has no influence on the groundwater. Positive experience of the tests and boiler operation lies in higher reactivity of sodium and sulphur as compared with conventional methods based on limestone. Within the scope of the secondary measures of elimination of sulphur oxides in combustion products, an experimental dry-method desulphurisation of combustion products was performed by blasting an agent containing sodium bicarbonate NaHCO3 (99.6 %) into the flue ways before the electrostatic precipitator in a coal-fuel furnace with the steam output of 220 t/h.

Lakes can be restored by the aeration method with the use of wind driven pulverising aerators. The method allows for moderate oxygenation of hypolimnion waters and it may be part of an integrated surface waters restoration system. The paper attempts to use the author’s method of maximum wind speeds to assess the volumetric flow of water through the aerator pulverisation mechanism. The study was conducted in 2018 in windy conditions of Lake Swarzędzkie. The introduction to the paper includes the characteristic of the lake and discusses the construction and operation of the wind driven pulverising aerator. Based on the maximum wind speed model, the theoretical capacity of the machine was calculated, which in the conditions of Lake Swarzędzkie was less than 111,500 m3 per year. Based on maximum wind speeds, the method of assessing the efficiency of the wind driven pulverising aerator is suitable for determining the volumetric flow rate of the pulverisation unit. This can significantly facilitate the planning of water reservoir restoration.

Any complete CFD model of pulverised coal-fired boiler needs to consider ash deposition phenomena. Wall boundary conditions (temperature and emissivity) should be temporally corrected to account for the effects of deposit growth on the combustion conditions. At present voluminous publications concerning ash related problems are available. The current paper presents development of an engineering tool integrating deposit formation models with the CFD code. It was then applied to two tangentially-fired boilers. The developed numerical tool was validated by comparing it with boiler evaporator power variation based on the on-line diagnostic system with the results from the full CFD simulation.

In this work problems associated with requirements related to pollution emissions in compliance with more restrictive standards, low-emission combustion technology, technical realization of the monitoring system as well as algorithms allowing combustion process diagnostics are discussed. Results of semi-industrial laboratory facility and industrial (power station) research are presented as well as the possibility of application of information obtained from the optical fibre monitoring system for combustion process control. Moreover, directions of further research aimed to limit combustion process environmental negative effects are presented.