Abstract:The performance of oil fume removal by electrostatic precipitation and the effects of electrode matching, electric field wind velocity, ionization and collection voltages on the removal efficiency are systematically investigated in this study. Dioctyl sebacate (DOS) aerosol in the range of 0.02~2.02 μm produced by an aerosol generator is used to simulate the oil fume. The number and mass concentration of particles are measured by an Electrical Low-Pressure Impactor plus (ELPI+) particle detector. Results show that the charging amount and migration distance of oil fume are the key factors affecting purification efficiency. Optimizing electrode matching significantly increases the purification efficiency. The purification efficiency is better enhanced by increasing ionization voltage in the charging zone than increasing collecting voltage in the collection zone. It is difficult to remove particles of 0.13~0.23 μm in diameter in the oil fume and its graded purification efficiency greatly affects the overall purification efficiency. The decrease in wind velocity of the electric field or increase in the number of modules in series can increase the residence time of oil fume in the electric field and thus improve the purification efficiency. The benefit-cost ratio of applying the oil fume purification system can be enhanced by scientifically matching the electric field wind velocity and the number of modules according to the allowed construction space and the flue gas fluctuation. Key words:electrostatic separation/ cooking oil fume/ electrode matching/ electric filed wind velocity/ purification efficiency.
图1实验系统照片及示意图 Figure1.Photo and system diagram of the experiment system
表1净化模块的电极配置及结构尺寸 Table1.Electrode matching and structure size of purification modules
模块形式
电极配置
荷电区
收尘区
通道 数量/个
放电线 数量/根
异极 间距/mm
长度/mm
通道 数量/个
异极 间距/mm
长度/mm
单区
齿-板
4
12
23.5
300
4
23.5
与荷电区共用
双区长电离短收尘
齿-板荷电+板-板收尘
4
8
23.5
165
8
9.5
135
双区短电离长收尘
齿-板荷电+板-板收尘
4
4
23.5
82.5
8
9.5
217.5
模块形式
电极配置
荷电区
收尘区
通道 数量/个
放电线 数量/根
异极 间距/mm
长度/mm
通道 数量/个
异极 间距/mm
长度/mm
单区
齿-板
4
12
23.5
300
4
23.5
与荷电区共用
双区长电离短收尘
齿-板荷电+板-板收尘
4
8
23.5
165
8
9.5
135
双区短电离长收尘
齿-板荷电+板-板收尘
4
4
23.5
82.5
8
9.5
217.5
下载: 导出CSV 表2不同模块数和电场风速条件下电场停留时间与净化效率的关系 Table2.Effects of electric field residence time on purification efficiency under different module numbers and wind velocities
电离 电压/kV
净化 效率/%
停留 时间/s
模块 数量/个
电场风速/ (m·s?1)
电离 电压/kV
净化 效率/%
停留 时间/s
模块 数量/个
电场风速/ (m·s?1)
18
90
0.17
2
3.5
20
90
0.16
3
4.5
18
90
0.2
3
4.5
20
90
0.17
2
3.5
18
90
0.22
4
5.5
20
90
0.2
3
4.5
18
90
0.24
2
2.5
20
90
0.22
4
5.5
18
90
0.26
3
3.5
20
90
0.24
2
2.5
18
90
0.27
4
4.5
20
90
0.26
3
3.5
18
90
0.34
4
3.5
20
90
0.27
4
4.5
18
90
0.36
3
2.5
20
90
0.34
4
3.5
18
90
0.48
4
2.5
20
90
0.36
3
2.5
18
95
0.22
4
5.5
20
90
0.48
4
2.5
18
95
0.24
2
2.5
20
95
0.22
4
5.5
18
95
0.26
3
3.5
20
95
0.24
2
2.5
18
95
0.27
4
4.5
20
95
0.26
3
3.5
18
95
0.34
4
3.5
20
95
0.27
4
4.5
18
95
0.36
3
2.5
20
95
0.34
4
3.5
18
95
0.48
4
2.5
20
95
0.36
3
2.5
20
90
0.12
1
2.5
20
95
0.48
4
2.5
20
90
0.13
2
3.5
电离 电压/kV
净化 效率/%
停留 时间/s
模块 数量/个
电场风速/ (m·s?1)
电离 电压/kV
净化 效率/%
停留 时间/s
模块 数量/个
电场风速/ (m·s?1)
18
90
0.17
2
3.5
20
90
0.16
3
4.5
18
90
0.2
3
4.5
20
90
0.17
2
3.5
18
90
0.22
4
5.5
20
90
0.2
3
4.5
18
90
0.24
2
2.5
20
90
0.22
4
5.5
18
90
0.26
3
3.5
20
90
0.24
2
2.5
18
90
0.27
4
4.5
20
90
0.26
3
3.5
18
90
0.34
4
3.5
20
90
0.27
4
4.5
18
90
0.36
3
2.5
20
90
0.34
4
3.5
18
90
0.48
4
2.5
20
90
0.36
3
2.5
18
95
0.22
4
5.5
20
90
0.48
4
2.5
18
95
0.24
2
2.5
20
95
0.22
4
5.5
18
95
0.26
3
3.5
20
95
0.24
2
2.5
18
95
0.27
4
4.5
20
95
0.26
3
3.5
18
95
0.34
4
3.5
20
95
0.27
4
4.5
18
95
0.36
3
2.5
20
95
0.34
4
3.5
18
95
0.48
4
2.5
20
95
0.36
3
2.5
20
90
0.12
1
2.5
20
95
0.48
4
2.5
20
90
0.13
2
3.5
下载: 导出CSV 表3收尘区供电电压对净化效率的影响 Table3.Effects of collecting voltage on purification efficiency
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[19]
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[20]
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School of Space and Environment, Beihang University, 100191, China Received Date: 2020-04-29 Accepted Date: 2020-10-10 Available Online: 2021-02-22 Keywords:electrostatic separation/ cooking oil fume/ electrode matching/ electric filed wind velocity/ purification efficiency Abstract:The performance of oil fume removal by electrostatic precipitation and the effects of electrode matching, electric field wind velocity, ionization and collection voltages on the removal efficiency are systematically investigated in this study. Dioctyl sebacate (DOS) aerosol in the range of 0.02~2.02 μm produced by an aerosol generator is used to simulate the oil fume. The number and mass concentration of particles are measured by an Electrical Low-Pressure Impactor plus (ELPI+) particle detector. Results show that the charging amount and migration distance of oil fume are the key factors affecting purification efficiency. Optimizing electrode matching significantly increases the purification efficiency. The purification efficiency is better enhanced by increasing ionization voltage in the charging zone than increasing collecting voltage in the collection zone. It is difficult to remove particles of 0.13~0.23 μm in diameter in the oil fume and its graded purification efficiency greatly affects the overall purification efficiency. The decrease in wind velocity of the electric field or increase in the number of modules in series can increase the residence time of oil fume in the electric field and thus improve the purification efficiency. The benefit-cost ratio of applying the oil fume purification system can be enhanced by scientifically matching the electric field wind velocity and the number of modules according to the allowed construction space and the flue gas fluctuation.