Heat Transfer Characteristics in Horizontal Rectangular Channel of Multi-Channel Cylinder Dryer

Lijie Qiao,Jixian Dong,Zhuozhi Yang,Sha Wang,Huan Liu,Bo Wang,Lingbo Kong 한국펄프·종이공학회 2020 펄프.종이기술 Vol.52 No.3

Characterization of the Pressure Drop during Condensation in Channels of Multi-Channel Cylinder Dryer Using Homogeneous and Separated Flow Models

Lijie Qiao,Jixian Dong,Huan Liu,Bo Wang,Sha Wang,Yan Dong,Haozeng Guo 한국펄프·종이공학회 2021 펄프.종이기술 Vol.53 No.4

Pea starch increases the dry matter flow at the distal ileum and reduces the amino acids digestibility in ileal digesta collected after 4 hours postprandial of pigs fed low-protein diets

Zhou Junyan,Wang Lu,Yang Guangxin,Yang Lijie,Zeng Xiangfang,Qiao Shiyan 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.7

Objective: The study was aimed to investigate the rules of postprandial changes in intestine digesta dry matter (DM) flow and amino acid digestibility of growing pigs fed low-protein (LP) diets made of different starch. Methods: Eight barrows (28.8±2.1 kg) with a T-cannula at the distal ileum were randomly allotted to an 8×3 Youden square design. Treatments included: waxy corn starch LP (WLP); corn starch LP (CLP) and pea starch LP (PLP). Diets were given at 08:00 and 20:00. Digesta samples were collected in six 2-h stages from 08:00 to 20:00. Results: The Cr concentrations of ileal digesta increased and then decreased in WLP and CLP, while increased continuously in PLP as time passed after postprandial (p<0.05). Higher average Cr concentrations (0.78% and 0.84% vs 0.70%; p<0.05) and lower average DM flow (181.1 g/kg and 166.3 g/kg vs 240.3 g/kg; p<0.001) were observed in WLP and CLP, compared with PLP. The apparent ileal digestibility coefficient of most amino acids in WLP and CLP increased compared with that in PLP. No difference in lysine or methionine digestibility was observed. When digesta were collected in 2-h periods, the apparent ileal digestibility coefficient of amino acids did not change over time. When digesta was collected in 4-h periods from 16:00 to 20:00 and 6-h periods from 14:00 to 20:00 (p<0.05), WLP and CLP showed markedly higher amino acid digestibility than PLP Conclusion: High-amylose slowly digested starch can increase the DM flow at the distal ileum and reduce the apparent ileal digestibility coefficient of amino acids of pigs fed LP diets. Compared with waxy corn starch and corn starch, pea starch reduced the digestibility of amino acids in digesta collected after 4 h postprandial. Objective: The study was aimed to investigate the rules of postprandial changes in intestine digesta dry matter (DM) flow and amino acid digestibility of growing pigs fed low-protein (LP) diets made of different starch.Methods: Eight barrows (28.8±2.1 kg) with a T-cannula at the distal ileum were randomly allotted to an 8×3 Youden square design. Treatments included: waxy corn starch LP (WLP); corn starch LP (CLP) and pea starch LP (PLP). Diets were given at 08:00 and 20:00. Digesta samples were collected in six 2-h stages from 08:00 to 20:00.Results: The Cr concentrations of ileal digesta increased and then decreased in WLP and CLP, while increased continuously in PLP as time passed after postprandial (p<0.05). Higher average Cr concentrations (0.78% and 0.84% vs 0.70%; p<0.05) and lower average DM flow (181.1 g/kg and 166.3 g/kg vs 240.3 g/kg; p<0.001) were observed in WLP and CLP, compared with PLP. The apparent ileal digestibility coefficient of most amino acids in WLP and CLP increased compared with that in PLP. No difference in lysine or methionine digestibility was observed. When digesta were collected in 2-h periods, the apparent ileal digestibility coefficient of amino acids did not change over time. When digesta was collected in 4-h periods from 16:00 to 20:00 and 6-h periods from 14:00 to 20:00 (p<0.05), WLP and CLP showed markedly higher amino acid digestibility than PLPConclusion: High-amylose slowly digested starch can increase the DM flow at the distal ileum and reduce the apparent ileal digestibility coefficient of amino acids of pigs fed LP diets. Compared with waxy corn starch and corn starch, pea starch reduced the digestibility of amino acids in digesta collected after 4 h postprandial.

Characterization of the Parameters for the Refining Intensity in Terms of Performance

Huan Liu,Jixian Dong,Hui Jing,Xiya Guo,Lijie Qiao 한국펄프·종이공학회 2019 펄프.종이기술 Vol.51 No.2

Refining intensity is typically used to measure the efficiency of refining in the pulp and paper industry, and the refining intensity is difficult to analyze due to the various parameters influencing it. In this paper, the previously published refining intensities of a disc refiner were analyzed, and the characterization parameters were proposed. Based on the bar interactions, the refining intensity was established using theoretical derivation. The cut edge length (CEL), the CEL-based characterization parameters and bar interactions (BI) characterization parameters were used to show that the CEL directly reflected the number of bar interaction points, but it had no direct relationship with the bar interaction area (BIA) and bar interaction length (BIL). By analyzing the relationship between the different refining intensities and the properties of the fibers or pulp, it could be concluded that the specific refining energy (SRE) better reflected the variations in the beating degree of the pulp during the refining process compared with the specific surface load (SSL) and BI-based refining intensities. Also, the intensity based on the bar interaction length (BIL) can better characterize the changes in the average fiber length. However, all the intensities analyzed in this paper do not comprehensively describe the refining process and cannot predict all the parameters of the pulp and fibers but only partly characterize their properties. Therefore, further studies are required to establish a more comprehensive and precise measure of refining intensity.

Effect of Pulp Properties on the Power Consumption in Low Consistency Refining

( Huan Liu ),( Jixian Dong ),( Kai Qi ),( Xiya Guo ),( Ying Yan ),( Lijie Qiao ),( Chuanwu Duan ),( Zhiming Zhao ) 한국목재공학회 2020 목재공학 Vol.48 No.6

The power consumption in the low consistency (LC) refining is an important indicator for the optimal control of the process and it is composed of the net power and the no-load power. The refining efficiency and process characterization of LC refining are directly affected by power consumption. In this paper, the effect of pulp consistency and average fiber length on the power consumption and refining efficiency were studied through the LC refining trials conducted by an experimental disc refiner. It is found that the curve of power-gap clearance can be divided into constant power section, power reduction section, and power increase section. And the no-load power and the adjustable domain of loading applied by the refining plates will increase as the increase of pulp consistency, while the increase of net power is larger than that of no-load power which makes the increasing of refining efficiency. Meanwhile, the adjustable domain of loading applied by the refining plates can be slightly improved by increasing the average fiber length, but its effect on the no-load power in the LC refining process can be neglected. The study of power consumption in LC refining is of positive significance for the proper selection of pulp properties in LC refining, in-depth exploration of refining mechanism, and energy consumption reduction in refining.

Accuracy of the Different Calculation Methods of Specific Edge Load

LIU Huan,DONG Jixian,LUO Chong,DUAN Chuanwu,GUO Xiya,QI Kai,QIAO Lijie,ZHAO Zhiming 한국펄프·종이공학회 2020 펄프.종이기술 Vol.52 No.5

Design a Laboratory Rotating Test Bench for the Multi-Channel Dryer Experiment

Sha Wang,Jixian Dong,Changke Tan,Bo Wang,Lijie Qiao,Huan Liu 한국펄프·종이공학회 2019 펄프.종이기술 Vol.51 No.5

The dryer of paper machine has problem in discharging condensate water. When the dryer rotates at a high speed, the condensate water that is not discharged in time will form a water ring, resulting in low drying efficiency and high energy consumption. Thus, based on the multi-channel dryer proposed by others, a series of experiments was carried out on multi-channel dryer under static condition. However, due to the fact that the research condition of condensation and heat transfer of multi-channel dryer is not exactly the same as the actual working condition, the multi-channel dryer has not been introduced to the market. To address the above problems, this paper presented a rotating test bench which can better simulate the actual working condition of dryer and expounded the working principle of the test bench, as well as the design and calculation of rotary device of the test bench. Finite element analysis software was used to analyze the stress on the dryer channel. In order to avoid resonance problems, modal numerical analysis was conducted on the test bench, which provided experimental conditions for the further study of multi-channel dryer.

No-Load Power of Disc Refiner in Low Consistency Refining

Huan LIU,Jixian DONG,Xiya GUO,Bo Wang,Qiao Lijie,Chuanwu DUAN,Kai QI,Lingbo Kong 한국펄프·종이공학회 2020 펄프.종이기술 Vol.52 No.2

Disc refiner is the key equipment in pulping and papermaking process, and the no-load power of disc refiner will directly affect the refining efficiency. So the refining efficiency and energy saving of the refining process will be promoted through theoretical and experimental study on it. In this paper, the measurement and the theoretical calculation method of the no-load power of disc refiner in low consistency refining were summarized. And the effects of pulp properties, control parameters and bar parameters of refining plate on no-load power were analyzed. The main research direction of the no-load power of disc refiner was proposed which has a positive significance on energy saving and pulp quality improvements of refining process.

Effects of strain on electronic properties of monolayer a-Fe2O3

Changmin Shi,Li C,Dongchao Wang,Hongmei Liu,Guangliang Cui,Lijie Qiao 한국물리학회 2016 Current Applied Physics Vol.16 No.5

Density functional theory was employed to study the strain-induced modification of electronic properties of advanced monolayer a-Fe2O3 for the first time. Theoretical results indicated that there was obvious dependency of band structure on strain. The band gap modulation could reach up to 29.0% for 7% compressive strain and to 10.6% for 7% tensile strain. The analytical results of fat-band structures demonstrated that the considerable modulation range of band gaps was mainly caused by the Fe-dz2 orbital.

Parametric Design and Performance Characteristic of Isometric Curved Bar Plate Based on SEL and SSL

Huan Liu,Jixian Dong,Chuanwu Duan,Ruifan Yang,Xiya Guo,Bo Wang,Kai Qi,Lijie Qiao,Sha Wang 한국펄프·종이공학회 2019 펄프.종이기술 Vol.51 No.5

Curved bar plate is common used in the pulp refining, but its design method is rather vague due it complex shape. A design method of isometric curved bar plate using two main parameters, the starting point and bar angle of central curve, was proposed in this paper and the calculation of characterization parameters of specific edge load (SEL) and specific surface load (SSL) was described. Isometric curved bar plates designed by two methods, one with fixed starting point and various bar angles and another with fixed bar angle and various starting points, were analyzed by characterization parameters of SEL and SSL. It would be expected to design isometric curved bar plate by the first method and the SEL would be a useful refining intensity to measure it in actual refining, however, the refining characteristics of different isometric curved bar plates should be further studied. The study on the design of isometric curved bar plate would be conductive to the research of curved bar plate and rapid design of it.