CO2 Reduction (Europe)
Customised Quality Improvers
Cement additives continue to play an important role in reducing the carbon footprint of cement production. Identifying the proper additive chemistry is crucial to the reduction in clinker and CO2 emissions while maintaining a substantial increase in cement performance. Currently available chemical technologies can offer a substantial decrease in clinker-to-cement ratio. When chemical technologies are customised effectively with a target cement composition, production of low clinker cement with a target ratio of clinker-to-cement ratio of 0.60 can be realised. The examples presented in this article show that both the technical and economical target can be achieved with the use of a suitable customised QI of the “CO2ST Reducers” series. A case study is presented, where net savings grew by approximately 50 per cent and the portion of savings from carbon has grown from 15 per cent to 43 per cent.
Blended Cements (China)
A Chinese Success Story
The process effects and the economic benefits of chemical additives are well understood, but their potential to reduce the carbon footprint of cement is a new frontier for many producers. Chemical additives improve the reactivity of cement, allowing increased clinker replacement with limestone and other SCM’s without loss of strength. This is an important lever for reducing cement plant CO2 emissions. A tailor-made additive was designed and put in place in one of the biggest cement plants in the world, located in western China. The use of the additive allowed the cement plant to deliver a better and more competitive PO 42.5 cement to the market, most notably having a higher SCM content and improved concrete rheology.
Blended Cements (Latin America)
The role of additives in Latin American low-clinker cements
The replacement of clinker by supplementary cementitious materials (SCMs) is currently one of the cement industry’s most effective approaches to reducing embodied carbon, and Latin America has been a leader in this field. As cement companies in the region continue making commitments to further reduce CO2 emissions, GCP Applied Technologies has been working with some producers to develop and supply strength-enhancing additives designed to allow ambitious levels of clinker replacement.
VRM Optimisation (South-east Asia)
VRMs: Add Stability, Not Water
While most vertical roller mill producers want to avoid injecting water onto the mill table, the need to achieve a target production level and product fineness makes this a regular practice. Grinding aids can help to avoid high levels of water injection. Case studies from Vietnam and Indonesia are reviewed, showing GCP grinding aids can offer significant reductions in water consumed for table stabilisation and bring measurable improvements in quality over and above those possible from traditional quality improvers, while as a minimum, maintaining other process parameters such as mill output and specific power consumption. There are many and varied VRM systems in the marketplace. The TAVERO VM range of grinding aids calls on the experience of over 150 field trials globally and, as such, it offers a unique market advantage to cement producers.
Chromium Reduction (Europe)
CrVI Innovations
The growth in Cr(VI)-reducing additives has been particularly strong in Europe because of EC directives, and they have become an integral part of many producers’ grinding programmes. Development firstly witnessed the addition of ferrous and tin sulphate powders and has progressed to liquid Cr(VI) additives, before the introduction of the new generation of improved reducers. GCP has pioneered the use of Cr(VI) reducers through its Synchro range and it sees further opportunities for new types of Cr(VI) reducers.