Research Highlight: Shandong University

- Jinan, China

Shandong University is located in Jinan CIty, Shandong Province, in the eastern part of China.

Professor Wang Wen Long and the team at Shandong University’s National Engineering Laboratory for Coal-fired Pollutants Emission Reduction have focused on complimentary utilization, solid wastes and life cycle assessment in their latest research. The research pertaining to Sulfoaluminate cementitious material at was presented 2017’s Coal Ash Asia conference in Beijing, China. Below is the abstract from this paper.

Complementary Utilization of Red Mud, FGD Gypsum and Other Solid Wastes to Prepare Sulfoaluminate Cementitious Material

Abstract: In the utilization processes of single solid waste, some fundamental problems always exist, including small solid waste dose, high cost, poor performance and low added value of products, difficulties in market exploitation, etc. Professor Wang proposes complementary utilization of varied solid wastes. High-performance sulfoaluminate cementitious materials (SCM) were successfully prepared by using 100% industrial solid wastes (red mud, flue gas desulfurization gypsum, aluminum slag and carbide slag) in an industrial rotary kiln at 1300°C. The product performances reached as high as 39MPa ,57MPa and 76MPa for 1d, 3d and 28d compressive strength, respectively. Environment impact assessment was also conducted for this process based on life cycle theory. It was proven that using industrial solid wastes to prepare SCM could reduce total environmental burden by 38.62% compared to using conventional materials. This technological conception can promote the large-scale utilization of massive solid waste and boost green and circular development of society.

Shandong University will return at AsianCAA’s Coal Ash Asia 2018 in Shuozhou City, the fly ash utilization center of China. Click below to register for CAA2018 and network with global academic and industry leaders during 3 days of exhibitions, seminars, scenic and industry tours.

Discussing Free CaO in CFB Ash and it’s Stability: Research Highlight from Coal Ash Asia 2017

- Beijing, China

Professor Qiao Xiu Chen from East China University of Science and Technology joined the discussion at Coal Ash Asia this past July 21-24 in Beijing, China. Prof Chen presented among industry leaders during the Fly Ash and Coal Gangue Track at the most recent AsianCAA event. The below abstract has been translated from its original submission to our proceedings.

Abstract: Circulating fluidized bed (CFB) boilers discharge 2 to 3 times as much ash per 1 kWh as pulverized coal-fired boilers. Overall, the amount of discarded CFB ash has drastically increased in China. However, there is no bulk utilization due to the different physiochemical properties of coal fly ash (CFA) from pulverized coal-fired boilers. One of the key issues is the amount of CaO left after burning, as CaO has negative effects on the soundness of cement. The national standard requires the maximum free CaO of 1% for F CFA and 4% for C CFA. The amount of lime in CFB ash is usually higher than 5% due to the desulfurization process. The utilization of CFB ash becomes harder when ash contains higher amounts of CaO. Presentation Abstracts

This conference we will show the chemical reaction variations of lime prepared at 800, 850, 900, 950, 1000, 1050, 1150, 1250, 1350°C. The calorimetry, precise measurement of lattice parameter and selected area microdiffraction of TEM were used for evaluation. The results showed that the calcite with a fineness of D100<76μm decomposed by 80% after the treatment at 800 or 850°C for 20 min. Complete decomposition occurred from the treatment at 900°C for 10 min. The maximum amount of CaO was 0.53% after the treatment at 1050°C. The amount of CaO started to be higher than 1% from the treatment at 1150°C and was more than 30% after the treatment at 1350°C for 20 min.

The CFB ash does not show a negative effect on the soundness of cement when the highest combustion temperature in the boiler is lower than 1050°C.

High Value-added Utilization of Coal-Related Solid Wastes

Dr. Li Hui Quan, a researcher at Chongqing University recently presented at the recent Coal Ash Asia conference in Beijing, China from July 21-24, 2017. The following is the fully translated abstract of their research. For more information, or to contact this researcher please contact the team at Asian Coal Ash Association.

Thermal power generation is an important component of Chinese energy. Shanxi and Inner Mongolia are regarded as the most important energy bases of China. Large amounts of coal gangue, fly ash, desulfurization gypsum and waste denitration catalyst emerge during the processes of coal mining and coal to electricity conversions. This causes terrible environmental problems due to the low waste utilization ratio. Many metal elements such as Al, Li and Ga, enrich coal-related solid wastes. Our team proposes a theoretical system of the mild separation of active components, the coordinated control of mineral structure and the step by step extraction of associated elements.

We found key technologies of the mild activation by proton acid and deep desilication of silicon, the extraction of alumina by sub-molten salt, the selective adsorption and separation of rare metals, and the directional conversion of silicon resources. The technical system of utilizing alumina & silicon, the step by step extraction of associated elements and the clean recycling & carrier generation of waste denitration catalyst are established. A 3000 tons / annual experimental production line of Al-Si composite from high-alumina fly ash by deep desilication process has been built. The Al-Si composite can replace 80 Bauxite sinter. The establishment of this technical system should be standard practice for the new recycling economy pattern of energy output; low emissions and material preparation, forming green, intelligent and cyclic factories with high resources and ecology amalgamation.

Presenters and Attendees at Coal Ash Asia 2017

-- Beijing

With CAA2017 just weeks away, we are proud to be hosting sizable international content and present our final speaker list at this year’s event. Our friends at the Slag Association of Asia will be hosting a concurrent event “Slag and Tailings Asia” in the same location at the Sheraton Grand Dongcheng Beijing Hotel.  Those who have registered for one will gain access to both events. All attendee will receive contact information for all 600 guests at this year's event and complimentary business and academic matching.

View below for our list of International Organisations in attendance as well as organisations presenting at this month’s concurrent events.

To see what we’ll be talking about at this year’s events click the links below for more information:

CAS at Coal Ash Asia 2017

- Baotou, Inner Mongolia

For the third year in a row, the Asian Coal Ash Association will be welcoming Coal Ash Solutions as the Business Matching Sponsors for this year’s Coal Ash Asia. The 3 day event will take place July 21-24 in Baotou, Inner Mongolia at the Shangri La Hotel. 

Coal Ash Solutions will be supporting international exchange by providing facilitation, introductions and translation of multiple meetings for each international delegate. Attendees will be able to request assistance with scheduling meetings as well as personal consultation on who would match best with their interests. Each attendee will receive a full contact list, included with each registration.

Business Matching will be available operating parallel to other Coal Ash Asia components including: oral presentations, poster exhibition, products and services exhibition and academic matching. We are delighted to be working with CAS. Our sponsors have facilitated over 70 successful meetings during our 2015 and 2016 events, and are looking forward to helping create meaningful exchange in 2017.

Click here to register for Coal Ash Asia and learn more about how Business Matching at this year’s event can work for you.

Sustainability Through CSA Cement

- Malaysia

Sustainability is simply the ability to meet the demands of today without negatively impacting the future. This goal is not easily met, especially in the construction industry. With demands for building materials on the rise in places like Malaysia and Vietnam, companies scramble to provide quality building materials such as concrete, cement, ceramic, etc, while still adhering to ever tightening restrictions on emission and waste disposal. Switching unfriendly environmental practices to a more efficient infrastructure of Building materials manufacturers providing suitable coal ash byproducts from local power station waste is not yet common practice. As legislative reform takes its time, researchers are attacking the problem of reusing industrial waste from all angles.

CSA (Calcium Sulfoaluminate) cement is another approach at reducing energy to produce environmentally friendlier cement.  Calcium Sulfoaluminate requires lower heating temperatures to produce. CSA is composed of a mixture of bauxite, limestone and gypsum and burning these at lower temperatures emits representatively lower amounts of carbon dioxide into the atmosphere. Also, the amount of limestone needed is much less. Limestone is said to be one of the key emitters of carbon dioxide in the sintering process. Using less materials and less energy is not only better for the environment, but more appealing to building materials manufacturers.

Dr. Tom Robl, Associate Director, Environmental & Coal Technologies at University of Kentucky’s Center for Applied Energy Research will be presenting the latest research and discussing CSA cement at the upcoming Coal Ash Asia. To join Tom at this year’s event please register by Clicking Here!

Research & Application: Steam Jet Milling in China

Processing Ultrafine Solid Waste Using Industrial Waste Heat with Low-cost

 - Mianyang, Sichuan, China

Jet Grinding is the dry method to obtaining minimum particle size effectively, but the high-energy consumption and small capacity greatly limit wide application. Creators and processors of industrial waste need to adapt large scale, low cost measures of ultrafine processing in order to make adaptation fiscally possible. Steam jet milling adopts high temperature mechanical technology and uses hot steam as media for high-speed movement to perform material pulverization.

 Currently researching the differences in medias being emitted through jet steam nozzles is Professor Chen Haiyan from Southwest University of Science and Technology, Sichuan Province, China. In his research, he compares the outlet airflow velocity with the same nozzle under different medias. The results show that compared with the 30℃compressed air, the crushing strength of the nozzle’s core region improved by 3 times under 300℃ superheated steam. Other parts of the jet steam process that were examined were the large scale and annular compound nozzles, flow field of grinding chamber, turbine classifier under superheated steam, and superheated steam bag filter.

 In a 30,000t/ year production line of desulphurization ash in a Pingshuo powder plant, ultrafine circulating fluidized bed ash was prepared by LNSJ-350A type steam jet mill.  Using superheated steam with temperature of 250℃and inlet pressure of 0.25 MPa supplied by a power plant, the results showed that the average particle size of the ultrafine circulating fluidized bed ash was 8.999 μm. The yield of ultrafine circulating fluidized bed ash was 73t/h. Steam consumption showed at 21.7 t and electricity consumption was 3.76k W·h per ton.

The strength and soundness conform to national standard requirements when the products are blended by a mass fraction of 10% for formulating composite Portland cement with the strength grade of 32.5.When medium particle size of desulphurization ash was about 4.76μm, the activity index could reach to 107%, which can also satisfy the requirement of S95 slag.

Professor Haiyuan, a welcomed speaker at Coal Ash Asia 2016 and 2017, explores this research alongside his colleagues at SUST, in Mianyang, Sichuan. The University was founded in 1939, and has over 29,000 students in enrolled. The campus was originally the Mianyang branch of Tsinghua University. Tsinghua University, another CAA2017 attendee, is another catalyst research facility for waste management and sustainability in China.