Cement News tagged under: Tech Forum
Effects of recirculation cells in cement kilns31 August 2021, Published under Cement NewsAs the raw material passes through the cement production process, recirculation cells are created. Due to the heterogenous nature of the fine materials, the composition in each cell is not uniform and as such, recirculation cells can impact on the final product. Figure 1: example of the relationship of hotmeal LSF to clinker LSF The manufacture of Portland cement clinker is necessarily concerned with the handling of very fine grains or dusts at various stages of production. Firs... |
Advanced grinding technology to reduce CO208 June 2021, Published under Cement NewsDr Michael Clark considers the role of grinding technology in reducing clinker content but retaining the cement strength class. The first industrial installation of a polysius® booster mill was at Bursa Cimento, Turkey In the last two Technical Forum articles, we have seen the imperative and challenge to reduce emissions associated with cement manufacture and that the major cement companies recognise this imperative and intend to rise to the challenge. To date the most effect... |
Advanced grinding technology to reduce CO208 June 2021, Published under Cement NewsDr Michael Clark considers the role of grinding technology in reducing clinker content but retaining the cement strength class. The first industrial installation of a polysius® booster mill was at Bursa Cimento, Turkey In the last two Technical Forum articles, we have seen the imperative and challenge to reduce emissions associated with cement manufacture and that the major cement companies recognise this imperative and intend to rise to the challenge. To date the most effect... |
The industry’s response to the decarbonisation challenge05 May 2021, Published under Cement NewsDr Michael Clark discusses the cement sector’s response and strategies in terms of the large-scale challenges involved with decarbonisation. LafargeHolcim’s Richmond plant in Canada, where it launched Project CO 2 MENT In last month’s Technical Forum we discussed the new CemNet online training material regarding the decarbonisation of cement manufacturing. This month we will turn our attention to the industry’s response to that challenge. There is no doubt that the world’s ma... |
Belite size distribution13 April 2021, Published under Cement NewsBelite size is affected by several factors ranging from raw materials, the length of the burning zone, the fuels used in the production process as well as the conditions in the cooling zone. Figure 1: example of belite crystal size distribution The sizes of belite crystals in Portland cement clinker depend on a number of factors that relate to the raw materials, burning zone length, fuels used and combustion efficiency. Raw materials The relative proportions of alite and ... |
Alkali-activated materials16 March 2021, Published under Cement NewsWhile blastfurnace slag and metakaolin are known to produce a binder phase following alkali activation, the range of alkali-activated materials is wider than these two materials. This month Arthur Harrisson provides an overview of low-and high-calcium precursors that are subjected to alkali activation to produce binders. Figure 1: fly ash, a low-calcium AAM precursor Materials that arise as waste or a by-product from industrial processes other than Portland cement manufacture ha... |
Financial ratio analysis23 February 2021, Published under Cement NewsCement producers should use financial ratio analysis to compare their performance with others around the world. However, this must be combined with peer group analysis to account for differing operational circumstances. Figure 1: EBITDA profit margin Financial ratio analysis is used to assess the condition and performance of cement companies based on the performance published in their financial statements, such as their income statement (profit and loss), statement of financial ... |
Fly ash and pozzolanas18 January 2021, Published under Cement NewsThe drive for alternative raw materials has put the spotlight on fly ash and pozzolanas. However, their use in cement has been around for some time. This month Arthur Harrisson looks at their origin and performance in cement. Pumice rock A pozzolana is a material which, when mixed with a hydraulic cement, will react with the lime from the cement and water to produce cementitious hydration products of its own. The most familiar types of pozzolanic materials in common use are low-... |
Process, mineralogy and cement quality08 December 2020, Published under Cement NewsThis month Arthur Harrisson looks at the relationship between temperature differences in the clinker manufacturing process, the composition of clinker produced and the quality of the final cement. Figure 1: variation of iron oxide and alumina in alite with clinker exit temperatures In a project to explore the influence of different temperature profiles on clinker characteristics, a range of commonly available measurements relating to the clinker manufacturing process were matche... |
Determining the cost24 November 2020, Published under Cement NewsIn this month’s Technical Forum, Dr Michael Clark considers how to reduce electricity costs by looking at how much is consumed and ways to lower the price of energy. While this is less of an issue in countries with low electricity costs, the lack of incentive to reduce costs could be a different kind of problem. Figure 1: the electricity cost of cement grinding The cost of something is a function of the price paid and the amount purchased or consumed. It is obvious, but there ar... |