CN-122006390-A - Multistage combined type efficient demisting device and method for desulfurizing tower

CN122006390ACN 122006390 ACN122006390 ACN 122006390ACN-122006390-A

Abstract

The invention relates to a multistage combined type efficient demisting device and method for a desulfurizing tower, wherein the multistage combined type efficient demisting device and method for the desulfurizing tower comprises a baffle demisting mechanism, a tube bundle demisting mechanism and a wire mesh demisting mechanism which are arranged above a spray layer in the desulfurizing tower and are sequentially arranged from bottom to top along the flow direction of flue gas, the baffle demisting mechanism comprises at least one layer of baffle group formed by a plurality of parallel baffle blades, the surface of each baffle blade is provided with a hydrophobic micro-groove, the hydrophobic micro-groove extends along the transverse direction of the baffle blade, the tube bundle demisting mechanism comprises a plurality of vertically arranged cyclone demisting tubes, each cyclone demisting tube comprises a tube body and a cyclone generator arranged at the bottom in the tube body, and a spiral liquid collecting groove is arranged on the inner wall of the tube body above the cyclone generator, extends from top to bottom in a spiral manner along the inner wall of the tube body and is communicated with a liquid outlet at the bottom of the tube body. The invention covers the full grain size range from coarse fog drops to superfine fog drops through three-level defogging cooperative work.

Inventors

Xin Zhongrui
QIU HUAHAI
CHI JUNFENG
MENG FANLIANG
HAN YANGYANG
SONG DA
ZHENG SHU
YANG LINYI
GAO YONG

Assignees

华电章丘发电有限公司

Dates

Publication Date: 20260512
Application Date: 20260331

Claims (10)

1. A multistage combined type efficient demisting device for a desulfurizing tower is characterized by comprising a baffle plate demisting mechanism, a tube bundle demisting mechanism and a wire mesh demisting mechanism which are arranged above a spray layer in the desulfurizing tower and are sequentially arranged from bottom to top along the flow direction of flue gas; The baffle plate demisting mechanism comprises at least one layer of baffle plate group formed by a plurality of baffle plate blades which are arranged in parallel, wherein the baffle plate blades comprise positive bending parts and negative bending parts which are alternately arranged along the flow direction of the flue gas to form a continuous double-S-shaped corrugated structure; The tube bundle demisting mechanism comprises a plurality of vertically arranged rotational flow demisting tubes, each rotational flow demisting tube comprises a tube body and a rotational flow generator arranged at the bottom in the tube body, a spiral liquid collecting groove is arranged on the inner wall of the tube body above the rotational flow generator, a liquid outlet is formed in the side wall of the bottom of the tube body, and the spiral liquid collecting groove extends along the inner wall of the tube body from top to bottom in a spiral manner and is communicated with the liquid outlet at the bottom of the tube body.
2. The multistage combined type efficient demisting device for the desulfurizing tower according to claim 1, wherein a guide hook bent towards the incoming flow direction of flue gas is arranged at the transition position of the forward bending part and the reverse bending part, and extends transversely along the baffle blade.
3. The multistage combined type efficient demisting device for a desulfurizing tower according to claim 1, wherein the hydrophobic micro-grooves are V-shaped grooves which are arranged at equal intervals along the longitudinal direction of the baffle blade.
4. The multi-stage combined type efficient demisting device for a desulfurizing tower according to claim 3, wherein the bottom of the hydrophobic micro-groove is provided with a slope along the extending direction, so that one end of the hydrophobic micro-groove is higher than the other end, and liquid drops converged in the hydrophobic micro-groove are guided to flow out from the lower end.
5. The multistage combined type efficient demisting device for a desulfurizing tower according to claim 1, wherein the cyclone generator comprises a central body and a plurality of guide vanes uniformly distributed around the periphery of the central body, and the guide vanes are connected to the central body and the inner wall of the pipe body.
6. The multistage combined type efficient demisting device for the desulfurizing tower according to claim 1, wherein the spiral liquid collecting tank is formed by the inner wall of a pipe body and a liquid collecting plate fixed on the inner wall of the pipe body.
7. The multistage combined type efficient demisting device for a desulfurizing tower according to claim 1, wherein bottoms of all the cyclone demisting pipes are fixed on a connecting plate and fixedly connected with the inner wall of the desulfurizing tower through the connecting plate, and the connecting plate is obliquely arranged so that liquid drops discharged from all liquid discharge ports can be converged on the surface of the connecting plate and flow along an oblique surface towards the lower end of the connecting plate.
8. The multi-stage combined type efficient demister for a desulfurizing tower according to claim 1, wherein the wire mesh demister mechanism comprises an upper support grid, a lower support grid and a wire mesh demisting layer filled between the upper support grid and the lower support grid.
9. The multistage combined type efficient demister for a desulfurizing tower according to claim 7, wherein a group of flushing mechanisms are respectively arranged above the baffle demisting mechanism, the tube bundle demisting mechanism and the wire mesh demisting mechanism.
10. A demisting method using the device according to any one of claims 1 to 9, comprising the steps of: (1) The flue gas carrying liquid drops firstly passes through the baffle plate demisting mechanism, the flow direction of the flue gas is changed through the baffle plate blades, large fog drops with the grain diameter of more than or equal to 20 mu m in the flue gas are trapped by utilizing the inertial collision effect, and the trapped liquid drops are converged along the hydrophobic micro-grooves with slopes and flow out from the lower end of the hydrophobic micro-grooves; (2) The flue gas treated in the step (1) passes through the tube bundle defogging mechanism, and after entering each cyclone defogging tube, the flue gas generates rotary flow through the cyclone generator, medium-particle-size fog drops with the particle size of 10-20 mu m in the flue gas are thrown to the inner wall of the cyclone defogging tube body by utilizing the centrifugal separation effect, and are guided to the liquid outlet by the spiral liquid collecting groove to be discharged; (3) And (3) finally passing the flue gas treated in the step (2) through the silk screen demisting mechanism to collect ultrafine liquid drops with the particle size less than or equal to 10 mu m in the flue gas.

Description

Multistage combined type efficient demisting device and method for desulfurizing tower Technical Field The invention relates to the technical field of industrial flue gas desulfurization, in particular to a multistage combined type efficient demisting device and method for a desulfurizing tower. Background The wet flue gas desulfurization technology is the main stream technology of flue gas desulfurization in the coal-fired power plant at present, and the desulfurization efficiency can reach more than 95%. In the wet desulfurization process, after the flue gas is fully contacted with desulfurization slurry, a large amount of fog drops containing pollutants such as sulfate, sulfite and the like can be carried. If the fog drops are discharged into the atmosphere along with the flue gas, secondary pollution such as gypsum rain and the like can be caused, downstream equipment can be corroded, and the safe operation of a chimney is influenced. Therefore, a demister must be installed above the spray level of the desulfurizing tower. The demisters widely used at present mainly comprise baffle demisters and tube bundle demisters. The baffle plate demister captures fog drops by virtue of inertial collision generated by airflow direction change, has higher capturing efficiency on fog drops with larger particle size (usually with particle size of 20-30 μm), but has lower capturing efficiency on fine fog drops with particle size of less than 20 μm due to smaller inertia, and is easy to escape along with airflow. The tube bundle demister only has good removal effect on mist drops with the medium particle diameter (10-20 μm) by utilizing the centrifugal separation principle. The defect that the particle size application range is limited exists in single defroster, is difficult to realize the high-efficient, the stable entrapment of thick full particle size range fog drops to follow, and current baffling board defroster and tube bank defroster structure can not in time water conservancy diversion discharge with the liquid drop of entrapment moreover, is taken away again by the upward air current easily, has showing the secondary and smugglies the problem, influences holistic defogging effect. Disclosure of Invention Aiming at the defects of the prior art, the invention provides a multistage combined type efficient demisting device and method for a desulfurizing tower. The invention overcomes the defects that the application range of a single demister for the particle size of the fog drops is narrow and the high-efficiency trapping of the full particle size cannot be realized in the prior art, and can trap the coarse fog drops to the superfine fog drops step by step and high efficiency. The invention provides a multistage combined type efficient demisting device for a desulfurizing tower, which comprises a baffle plate demisting mechanism, a tube bundle demisting mechanism and a wire mesh demisting mechanism which are arranged above a spray layer in the desulfurizing tower and are sequentially arranged from bottom to top along the flow direction of flue gas; The baffle plate demisting mechanism comprises at least one layer of baffle plate group formed by a plurality of baffle plate blades which are arranged in parallel, wherein the baffle plate blades comprise positive bending parts and negative bending parts which are alternately arranged along the flow direction of the flue gas to form a continuous double-S-shaped corrugated structure; The tube bundle demisting mechanism comprises a plurality of vertically arranged rotational flow demisting tubes, each rotational flow demisting tube comprises a tube body and a rotational flow generator arranged at the bottom in the tube body, a spiral liquid collecting groove is arranged on the inner wall of the tube body above the rotational flow generator, a liquid outlet is formed in the side wall of the bottom of the tube body, and the spiral liquid collecting groove extends along the inner wall of the tube body from top to bottom in a spiral manner and is communicated with the liquid outlet at the bottom of the tube body. Preferably, a guide hook bent towards the incoming flow direction of the flue gas is arranged at the transition part of the forward bending part and the reverse bending part, and extends transversely along the baffle plate blade for enhancing the mist drop interception effect. Preferably, the hydrophobic micro-grooves are formed by baffle blades and liquid guide plates fixed on the surfaces of the baffle blades, and the hydrophobic micro-grooves are formed by a plurality of the baffle blades longitudinally arranged along the baffle blades. Preferably, the bottom of the hydrophobic micro groove has a slope along the extending direction, so that one end of the hydrophobic micro groove is higher than the other end, and the liquid drops converged in the hydrophobic micro groove are guided to flow out from the lower end. Preferably, each baffle blade is fixed with the i