Progress 09/01/15 to 02/28/18
Outputs
Target Audience:The audiences to which the project outcomes were communicated included cement manufacturers, ready-mix concrete industry, precast/prestressed concrete industry, construction industry, power plants using biomas fuel, and government and private entities involved in management of infrastructure systems. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?The project has engaged two staff members of Metna Co. and two graduate students, who received significant training in the field of sustainable hydraulic cements employing non-wood biomass ash as a major raw material. The project findings were also communicated to members of cement, concrete, construciton, infrastructure management and power industries as part of the professional development efforts required to facilitate market transition of the technology. How have the results been disseminated to communities of interest?Presentations have been made to technical and business members of cement, concrete, construction, infrastructure management and power industries on the project goals and outcomes, and the benefits of the commercial benefits that can be realized by the targeted industries. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
IMPACt There is a gorwing trend towards the use of biomass as fuel for more sustainable enrgy production . Combustion of biomass for power generation leads to generation of significant quantities of ash. This project developed a new class of igh-performance, sustainable and economical hydraulic cement that makes large-volume and value-added use of the major classes of non-wood biomass ash for concrete production. Non-wood biomass ash thus offers significant value in production of cement and concrete. The technology would benefit the economics and sustainability of generating green energy using biomass as fuel. SUMMARY Hydraulic cement formulations were developed with non-wood biomass ash as a primary raw material. These hydraulic cements meet the ASTM C1157 requirements for use as 'General Use' cements. Values of wheat straw, corn stalk, rice husk, and cotton gin combustion ashes as raw materials for production of hydraulic cements were demonstrated. These non-wood biomass ashes were thoroughly characterized in order to assess the contributions they can made towards an alkali aluminosilicate cement chemistry. Wheat straw, corn stalk and cotton gin ashes were found to provide notable quantities of silicon, potassium and calcium for processing of hydraulic cements. Rice husk ash has a distinct chemistry, and offers primarily reactive silica for use in production of hydraulic cements. Two abundant industrial byproducts, granulated blast furnace slag and coal fly ash, were used to supplement the chemistry of non-wood biomass ash as raw materials for production of an alkali aluminosilicate cement. Other raw materials, used in relatively small concentrations, included sources of alkalis, and additives for achieving improved dimensional stability and deicer salt scaling resistance. These raw materials were transformed into hydraulic cements using a sustainable and economical mechanochemical process. This process involves simple ball-milling of the blend of raw materials at room temperature. The raw materials formulations were refined and optimized in order to produce hydraulic cements that meet standard requirements, and also produce concrete materials that match or surpass the fresh mix rheology, and the hardened material physical, mechanical, chemical stability, barrier, durability, fire resistance and safety attributes of Portland cement concrete. Room-temperature curing of concrete was emphasized in order to maximize the market potential of non-wood biomass ash-based hydraulic cements. The scalability of the mechanochemical approach to processing of hydraulic cements was verified. For this purpose, a preliminary theoretical basis was devised for scale-up of the process, and the mechanochemical approach to processing of an example non-wood biomass ash-based hydraulic cement was implemented at pilot scale. The resulting hydraulic cement was found to provide qualities approaching those of the cement processed at laboratory scale. The hydraulic cement processed at pilot scale was used for industrial-scale production of concrete, and field construction of a pavement in mid-Michigan with non-wood biomass ash-based hydraulic cement concrete. Conventional concrete mixing, transportation and construction practices were found to be applicable to non-wood biomass ash-based hydraulic cement concrete. The concrete pavement has performed satisfactorily over several months that included exposure to the winder weather in mid-Michigan. Competitive analyses were performed in order to assess the economic and sustainability merits of non-wood biomass ash-based hydraulic cements versus Portland cement. The results indicated that non-wood biomass ash-based hydraulic cements have carbon footprints that are significantly below that of Portland cement. Their energy contents are also notably below that of Portland cement. An initial economic assessment pointed at the economical viability of the mechanochemically processed non-wood biomass ash-based hydraulic cements. The balance of performance, cost, sustainability and safety provided by non-wood biomass ash-based hydraulic cement make them viable additions to the slate of sustainable and high-performance hydraulic cements based on alkali aluminosilicate chemistry that are under development for enhancing the longevity, sustainability and life-cycle economics of vast concrete-based infrastructure systems. CONCLUSIONS Non-wood biomass ash can make Si, Ca, K, Al and other elements available for production of hydraulic cements based predominantly upon the alkali aluminosilicate chemistry. Supplementing the chemistry of non-wood biomass ash with those of coal fly ash, granulated blast furnace slag and sources of alkalis can yield a balanced chemistry for production of alkali aluminosilicate cements. Minor quantities of additives would also be needed for producing cements with desired set time that yields hydration products with desired deicer salt scaling resistance and dimensional stability. Combustion ashes of wheat straw, corn stalk and cotton gin offer similar compositional and reactivity attributes for use in production of hydraulic cements with alkali aluminosilicate chemistry. Rice husk ash, on the other hand, has a distinct chemistry that is rich in reactive silica. Hydraulic cements can be formulated with all these non-wood biomass ashes. Mechanochemical processing is a sustainable and economical means of transforming the non-wood biomass ash and supplementary raw materials into hydraulic cements that meet standard requirements for use in concrete production. Mechanochemically processed hydraulic cements formulated with non-wood biomass ash offer a desired balance of fresh mix rheology, set time, and hardened material mechanical properties, chemical and dimensional stability, barrier qualities, and durability characteristics. Concrete materials prepared with these hydraulic cements reflect their desired balance of qualities, and provide desired protection against corrosion of reinforcing steel, and fire resistance. The mechanochemical approach to processing of non-wood biomass ash-based hydraulic cements is scalable. Energy-based criteria were employed to establish the scale-up the mechanochemical processing of hydraulic cements. Pilot-scale implementation of the process was successful, and yielded a hydraulic cement that offered a desired balance of qualities. The non-wood biomass ash-based hydraulic cement processed mechanochemically at pilot scale was used successfully for industrial-scale production of concrete, which was used in field construction of a concrete pavement. Conventional concrete construction practices were found to be applicable to the non-wood biomass ash-based hydraulic cement concrete. The field performance of non-wood biomass ash-based hydraulic cement concrete under service exposures has been satisfactory. Mechanochemically processed non-wood biomass ash-based hydraulic cements have a distinctly low carbon footprint and relatively low energy content when compared with Portland cement. The economics of non-wood biomass ash-based hydraulic cement is also favorable when compared with Portland cement. Non-wood biomass ash-based hydraulic cements are safe, and do not release hazardous constituents to the environment. The milling conditions established traditionally for size reduction are not necessarily optimum for rendering mechanochemical effects. There is a need to optimize milling conditions for more effective and efficient mechanochemical processing of hydraulic cements. The intensity of the energy transferred to raw materials in each instance of impact needs to be raised in mechanochemical processing of hydraulic cements.
Publications
- Type:
Journal Articles
Status:
Under Review
Year Published:
2019
Citation:
Balachandra, A. and Soroushian, P., "Development and Characterization of Non-Wood Biomass Ash-Based Hydraulic Cement Concrete," Cement and Concrete Research
- Type:
Other
Status:
Published
Year Published:
2018
Citation:
Balachandra, A. and Soroushian, P., "Value-Added Use of Non-Wood Biomass Combustion Ash Towards Production of Sustainable, Economical and High-Performance Geopolymer Concrete," Final Report, USDA Phase II SBIR Award No. 2015-33610-24100, April 2018, 103 pp.
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Progress 09/01/15 to 08/31/16
Outputs
Target Audience:Power plants utilizing biomass as fuel, Cement manufacturers, Concrete materials and products suppliers, Construction industry, Public and private owners of infrastructure systems, Waste management industry, Environmental agencies. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?The PI and project staff gained more experience as leading experts in value-added use of (non-wood) biomass ash in inorganic (geopolymer) binders for concrete production. A student intern is also involved in the project, and is gaining experience in the field. How have the results been disseminated to communities of interest?Power plants that use biomass have supplied the ash, and the results are communicated to them. Results are also communicated to members of the concrete industry that will be involved in implementation of field demonstration projects. The publication on project outcomes that will appear in September 2016 in a highly respected journal widely distributed within the concrete industry will play a key role in disseminating the technology within the concrete industry. What do you plan to do during the next reporting period to accomplish the goals?The work planned for the next reporting period covers: (i) scale-up of the production process of hydraulic cements formulated with non-wood biomass ash; (ii) industrial-scale production of non-wood biomass ash-based hydraulic cement concrete; (iii) field construction of non-wood biomass ash-based hydraulic cement concrete; (iv) thorough characterization of non-wood biomass ash-based hydraulic cement and concrete materials; and (v) competetive performance, cost and sustainability analysis non-wood biomass ash-based hydraulic cement and concrete materials.
Impacts
What was accomplished under these goals?
Values of wheat straw, corn stalk, rice hull and wood combustion ashes as raw materials for production of hydraulic cements suiting concrete production were evaluated. Medium scale combustion techniques were supplemented with heat treatment of the resulting ash in order to produce non-wood biomass ashes which matched the loss on ignition, alkali solubility, alkalinity, morphology, particle size distribution and chemistry of biomass ashes generated in industrial power plants. Test methods and criteria were developed for qualification of non-wood biomass ashes as raw materials for production of hydraulic cements. Different formulations were developed for transforming non-wood biomass ashes into hydraulic cements which meet the ASTM C1157 requirements for the 'General Use' class of cement. Besides the ASTM C1157 requirements, moisture stability was found to be an important consideration in development of non-wood biomass ash-based hydraulic cements. The chemistry of non-wood biomass ash had to be supplemented with those of coal fly ash, calcined clay and a calcium source in order to achieve a desired balance of strength development characteristics and moisture resistance. These precursors were subjected to ball-milling together with a source of alkali metal cations in order to produce hydraulic cements. This is a simple approach to processing of non-wood biomass ash-based hydraulic cements, which avoids the energy-intensive and polluting high-temperature step used in production of Portland cement. Experimental investigations were undertaken to identify preferred sources of calcium, and evaluate the effects of the coal fly ash type on the non-wood biomass ash-based hydraulic cement performance. The formulation was further refined through addition of set-retarders which made the hydraulic cement compatible with the common pace of concrete construction, and also with the addition of water-reducers to lower the water demand for achieving higher levels of performance. Besides the set time and strength development characteristics of non-wood biomass ash-based hydraulic cements, their dimensional stability was also evaluated. It was found that further refinements of the hydraulic cement formulations are required for thorough satisfactions of the dimensional stability requirements relevant to hydraulic cements. The bulk of the development effort was conducted using wheat straw ash-based hydraulic cements. The results were found to be directly applicable to corn stalk ash-based hydraulic cements. The distinct chemistry and specific surface area of rice hull ash, however, required development of alternative formulations for processing of rice hull ash-based hydraulic cements. The tailored formulations based on rice hull ash exhibited qualities which were similar or superior to those developed with wheat straw and corn stalk ash. The high recycled contents of the non-wood biomass ash-based hydraulic cements developed in the project raise concerns about the potential for excess statistical variations and lack of consistence/reliability of these hydraulic cements. An experimental program was undertaken in order to assess the statistical variations of wheat straw ash-based hydraulic cements versus maximum limits specified by ASTM. Two different types of wheat straw were considered in this experimental program, and replicated processing and testing of wheat straw ash-based hydraulic cements were performed with each straw type. The results were promising, and the ranges covered by various replicated test results were below the maximum limits specified by ASTM, suggesting that the statistical variations of various aspects of the wheat straw ash-based hydraulic cement are under control.
Publications
- Type:
Journal Articles
Status:
Awaiting Publication
Year Published:
2016
Citation:
Matalkah, F., Soroushian, P., Abideen, S.U. and Peyvandi, A., Use of Non-Wood Biomass Ash in Development of Alkali-Activated Concrete, Construction and Building Materials, Vol. 121, No. 15, September 2016, pp. 491-500.
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