Response of energy-size reduction to the control of circulating load in vertical spindle pulverizer

• Autorzy: Li H. , He Y. , Zhang Y. , Ge Z. , Xie W. , Wang S. , Li K.

Identyfikatory

DOI

10.5277/ppmp170210

• Języki publikacji: EN

Abstrakty

EN

In the vertical spindle pulverizer (VSP), the large circulation ratio and high ash and sulfur contents in circulating load would result in intensive energy consumption and low grinding efficiency. Although the control of circulating load would help increase the energy efficiency, no quantitative study has been conducted due to the high temperature and pressure in the closed VSP. In this study, response of energy-size reduction to the control of circulating load was studied by the experimental simulation method. Coal mixtures with fine/coarse ratio of 11:1, 8:1 and 6:1 were ground by a lab-scale roller mill. Energy-size reductions of the coarse coal were compared to evaluate the influence of circulating load control. Results showed that the product with the coarse coal increased by 30% when the specific breakage energy was 1.0 kWht–1 as the circulation ratio decreased from 11 to 6. Meanwhile, a breakage characteristic index of the coarse coal was two times higher due to the cushioning effect of fines. Besides, decrease of circulation ratio led to increase of the breakage rate of coarse coal, and the energy saving improved by 57%. With the same energy input of 2.0 kWht-1, the yield of –0.09 mm pulverized fuel (PF) increased from 22 to 43%. Therefore, controlling the circulating load is an effective method to improve the breakage rate of coarse coal and energy efficiency for PF generation.

Słowa kluczowe

EN

circulating load control; response of energy-size reduction; mixture grinding; energy efficiency

• Wydawca: Oficyna Wydawnicza Politechniki Wrocławskiej
• Czasopismo: Physicochemical Problems of Mineral Processing
• Rocznik: 2017
• Tom: Vol. 53, iss. 2
• Strony: 793--801
• Opis fizyczny: Bibliogr. 22 poz., rys., tab.

Twórcy

autor

Li H.

• School of Chemical Engineering and Technology, China University of Mining & Technology, Xuzhou, Jiangsu 221116, China

autor

He Y.

• School of Chemical Engineering and Technology, China University of Mining & Technology, Xuzhou, Jiangsu 221116, China
• Advanced Analysis & Computation Center, China University of Mining & Technology, Xuzhou, Jiangsu 221116, China

autor

Zhang Y.

• School of Chemical Engineering and Technology, China University of Mining & Technology, Xuzhou, Jiangsu 221116, China

autor

Ge Z.

• School of Chemical Engineering and Technology, China University of Mining & Technology, Xuzhou, Jiangsu 221116, China

autor

Xie W.

• School of Chemical Engineering and Technology, China University of Mining & Technology, Xuzhou, Jiangsu 221116, China

autor

Wang S.

• Advanced Analysis & Computation Center, China University of Mining & Technology, Xuzhou, Jiangsu 221116, China

autor

Li K.

• School of Chemical Engineering and Technology, China University of Mining & Technology, Xuzhou, Jiangsu 221116, China

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