Cement News tagged under: Tech Forum

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Magnesia in clinker

18 November 2019, Published under Cement News

Magnesia is often present in clinker as periclase, which is formed of free MgO. However, periclase does not always provide a welcome part of the clinker’s composition and can lead to significant volume expansion of the concrete that is made with cement manufactured from such clinkers. Figure 1: periclase inclusions in belite. The belite crystal with two inclusions is 12µm across In cement clinker magnesia (MgO) can be present as a substituent in each of the primary clinker miner...

Progress in quantification of clinker phases

21 October 2019, Published under Cement News

The quantification of clinker phases is not always straightforward and often raises a number of questions. However, there has recently been significant progress in this area, as outlined below. Figure 1: share of M3 alite determined by XRD related to MGO/SO 3 The National Institute of Science and Technology (NIST) is an agency of the United States Department of Commerce which, amongst other activities, provides reference samples of cement that have been characterised in terms o...

New opportunities for Europe

07 October 2019, Published under Cement News

Dr Michael Clark looks at how the EU ETS is expected to change the face of European clinker manufacture. With the price of carbon credits rising, it could become more economically viable to import clinker and grind it upon arrival in Europe through the use of smaller grinding facilities. By Dr Michael Clark, UK. Cem’In’EU’s new facility in Tonneins, southwest France, is an example of the new wave of clinker-importing grinding units expected to arrive The summer of 2019 has se...

Construction and demolition waste as clinker raw material

09 September 2019, Published under Cement News

The concept of the circular economy encourages the reuse of waste products as raw materials in the production of cement. Arthur Harrisson looks at the use of construction and demolition waste as a raw material for clinker. Initial crushing of concrete produces aggregate containing a significant proportion of mortar Carbon dioxide is produced during cement clinker manufacture from two sources. Firstly, the primary raw material for clinker is limestone, which is predominantly calc...

New supplementary cementitious materials

19 August 2019, Published under Cement News

The search for new supplementary cementitious materials (SCMs) is ongoing. A recent review of existing SCMs and the potential for new ones caught the eye of Arthur Harrisson and provided further potential for investigation. A disused slate quarry: a potential SCM? A recent review 1 of the availability of supplementary cementitious materials (SCMs) and the possibility for expanding the choice of those available examined the range of emerging SCM sources and also the means of tes...

Belite in Portland clinker

22 July 2019, Published under Cement News

While belite is often represented as a pure dicalcium silicate, in practice the phase contains a range of impurities. Arthur Harrisson highlights the differences in belite composition and examines the causes of such impurities. Type I belite crystals with dark laminations containing exsolved matter The belite phase in Portland cement clinker is often characterised as dicalcium silicate or C 2 S, implying a lime-to-silica ratio of 2:1. The ratio refers to the number of CaO units ...

Solar to the rescue

02 July 2019, Published under Cement News

Dr Clark looks at how concentrated solar energy could help the cement industry move closer to carbon neutrality. Furthermore, the latest solar technology could make other carbon-reduction strategies more viable. Concentrated solar energy could make carbon capture and storage more economically viable All readers will be well aware of the CO 2 emissions challenge currently facing the cement industry. The share of man-made CO 2 emissions created by the cement industry is often qu...

Using plant cost profiles

16 May 2019, Published under Cement News

As in January 2018, Dr Michael Clark has once more spent most of the last month developing manufacturing cost profiles for cement factories in different geographies across the globe. This time, Dr Clark considers how these profiles may be used to provide a competitive advantage. Holcim established its facility in Ste Genevieve, Missouri, USA, benefiting from the low distribution costs due to its convenient location on the Mississippi River Regular readers of the Technical For...

The finishing lime

18 February 2019, Published under Cement News

In this month’s Technical Forum, Dr Clark examines the conditions and complications under which raw materials compete for the available lime during the production of clinker. During the production of clinker, raw materials join a competition for available lime In the Technical Forum, Cemtech Workshops and CemNet Online Training we are always trying to improve understanding of the technology of the cement manufacturing process. At the heart of that process is the combination o...

Evaluating an EPC project

30 January 2019, Published under Cement News

In this month’s Technical Forum, Dr Michael Clark looks at the essential factors that cement producers must take into account when choosing the right contractor for a potential EPC project. Time to completion is an important factor to consider, as it will impact the net present value At the beginning of each year, ICR provides an update on new cement capacity projects around the world. Capacity development projects are an infrequent and possibly unique event for a cement company...