The first step towards condition based maintenance of the milling plant is the implementation of online condition monitoring of the mill. The following paper presents and analyses methods of monitoring the key performance factors of a vertical spindle mill that is suited for implementation on older power stations, i.e. the quantity (mass flow rate) and quality (particle fineness) of the pulverised fuel produced by the mill. It is shown herein that the mill throughput can be monitored on-line using a simple mill energy balance that successfully predicts the coal throughput within 2.33% as compared to a calibrated coal feeder. A sensitivity analysis reveals that the coal moisture is a critical measurement for this method to be adopted as an on-line mass flow monitoring tool. A laser based particle size analyser tool was tested for use in the power plant environment as an online monitoring solution to measure pulverised fuel fineness. It was revealed that several factors around the set-up and operation of the instrument have an influence on the perceived results. Although the instrument showed good precision and repeatability of results, these factors must be taken into account in order to improve the accuracy of the reported results before the instrument can be commissioned as an on-line monitoring solution.

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.