Cement additives are materials added to cement for the optimization of the cement properties and the cement grinding process. Cement additives are classified into different product groups such as grinding aids, strength enhancers and performance enhancers.
Cement Additives are a Popular Choice Because They
- Positively affect the production process and the quality of cement
- Improve defined cement properties, e.g. powder flowability, strength development, mortar workability and durability
- Adjust the cement quality to meet the demands set by relevant standards and cement customers
- Ensure less environmental impact by reducing utilization of energy and resources combined with minimized carbon footprint
- Contribute to the profitability of cement plants
Sika’s Cement Additives Technologies
Each individual cement plant has different characteristics of local raw materials, availability of possible clinker replacements (such as supplementary cementing materials - SCM) and varying conditions during the cement grinding process.
In addition, local standards and customers’ needs regarding cement performance vary due to unique climate and construction methods. Therefore, the solution for highest possible production rates or maximized use of supplementary cementitious materials needs to be adjusted individually.
Sika offers many types of cement additives known to improve cement quality, increase production efficiency and meet your local demands:
Grinding Aids are used in the cement mill (Ball Mill, Vertical Roller Mill, HoroMill) to increase the productivity, save electrical energy and/or to increase the fineness and improve defined cement properties, e.g. powder flowability.
A typical example is SikaGrind®-400. Based on the knowledge of its design and production, Sika has developed a polycarboxylate polymer-powered grinding aid technology, which is able to improve the performance of traditional grinding aids. A typical example is SikaGrind®-840.
There are several ways to increase the mechanical strength of cement. It is common to use cement additives that increase the mechanical strength by chemical activation, without changing the cement surface and particle size distribution. Alkanolamines are frequently used and are able to increase the compressive strength (at different or all age) by max. five MPa. Typical examples are SikaGrind®-200 and SikaGrind®-700. These admixtures increase the productivity of the grinding aid at the same time.
Clinker is often replaced with supplementary cementitious materials (SCM) such as granulated blast furnace slag, natural pozzolanes and fly ash in order to reduce CO2 emissions and material cost. However, SCM may counteract strength development, powder flowability, mortar workability and durability, which are critical for cement quality. Examples of our performance enhancers are SikaGrind® LS-43 for Portland Limestone Cement production and SikaGrind®-184 for slag cement.
Sika’s Technical Services for Cement Specialists
Understand local situations and define targets
We understand and support your business. Whether being confronted with a special problem or in the daily challenge to improve your profitability, Sika will assist you in reaching your targets. Local conditions and demands vary strongly, making it necessary to handle every plant individually. Sika can offer tailor-made solutions, designed to meet individual challenges, thereby working together as partners with one joint target.
Laboratory pre-trials to evaluate trends
To begin the product and process optimization, well-defined and technically feasible targets related to the present production and quality parameters are agreed upon. Based on our experience in cement production process and product know-how, one or two SikaGrind® products are recommended for plant trials. If necessary, laboratory pre-trials can be arranged in one of our regional cement laboratories.
Execution of plant trials by Sika experts
Preparation and execution of plant trials are handled by Sika staff in cooperation with plant staff. The production data and cement analysis results determined in our specialized laboratories are than discussed between you and Sika’s cement specialists, to agree upon the target fulfillment and define next steps.
Evaluation of cement quality in laboratory analysis
In case of inconclusive results or the need for further optimization work, another plant trial cycle with potential product modification and laboratory pre-trials may be necessary. Our analytical laboratory is well-equipped with modern instruments and well-trained technicians.
By reducing the specific grinding energy and reducing the clinker factor, SikaGrind® contributes to less CO2 emissions.