Process and device for continuous treatment of high-concentration organic wastewater

Patent metadata

Field	Value
Publication number	US-2021331943-A1
Application number	US-202117367642-A
Country	US
Kind code	A1
Filing date	Jul 6, 2021
Priority date	Dec 25, 2019
Publication date	Oct 28, 2021
Grant date	—

Abstract

The present invention provides a process for continuous treatment of high-concentration organic wastewater and a device for continuous treatment of high-concentration organic wastewater. The process of the present application is that: high-concentration organic wastewater is continuously separated through the synergistic interaction of a multilayer evaporator and a heat pump, and the generated wastewater steam containing light components is continuously subjected to desulfurization and catalytic combustion after being mixed with air in a gaseous form, the treated wastewater can meet discharge standards, and heavy components of the generated wastewater can be recycled. After the desulfurizing agent in a first desulfurizer and the catalyst in a first catalytic combustor are deactivated, the generated wastewater steam containing the light components can be switched to a second desulfurizer and a second catalytic combustor for reaction, and air can be introduced into the deactivated catalyst and desulfurizing agent for in-situ regeneration at a high temperature.

First claim

What is claimed is:

1 . A process for continuous treatment of high-concentration organic wastewater, comprising the following steps:
step 1, separation of high-concentration organic wastewater: under a transport action of a feeding pump ( 1 ), high-concentration organic wastewater enters a multilayer evaporator ( 4 ) through a liquid flowmeter ( 3 ) for evaporation and separation, so that organic light components and water in high-concentration organic wastewater are vaporized to form wastewater steam containing light components, the generated wastewater steam containing the light components is extracted from a heat pump ( 5 ) through a top outlet of the multilayer evaporator ( 4 ), and heavy components of the multilayer evaporated wastewater is discharged from a second valve ( 22 ) through a bottom outlet of the multilayer evaporator ( 4 ); step 2, purification of the wastewater steam containing the light components: after sequentially flowing through a cold fluid channel of a heat exchanger ( 6 ) and a first preheater ( 7 ) to be heated, the wastewater steam containing the light components is introduced into a first desulfurizer ( 8 ) together with air for a desulfurization reaction, the desulfurized tail gas is discharged from a bottom of the first desulfurizer ( 8 ) and enters a first catalytic combustor ( 9 ) for a purification reaction, and after flowing into a hot fluid channel of the heat exchanger ( 6 ) for heat exchange, the purified high-temperature steam heats the multilayer evaporator ( 4 ) as a heat source, and is discharged as purified water after heat exchange and condensation; and step 3, regeneration of a desulfurizing agent and a catalyst: after the desulfurizing agent in the first desulfurizer ( 8 ) and the catalyst in the first catalytic combustor ( 9 ) are deactivated, the generated wastewater steam containing the light components is switched to a second reaction route, entering a second desulfurizer ( 10 ) at first together with air for a desulfurization reaction, and then entering a second catalytic combustor ( 11 ) for a purification reaction, and the purified high-temperature steam heats the multilayer evaporator ( 4 ) as a heat source after passing through the hot fluid channel of the heat exchanger ( 6 ); and air is respectively introduced into the first desulfurizer ( 8 ) and the first catalytic combustor ( 9 ) for regeneration and activation at 500-600° C., and the regenerated tail gas discharged from the first desulfurizer ( 8 ) and the first catalytic combustor ( 9 ) is merged and purified centralizedly.

2 . The process for continuous treatment of high-concentration organic wastewater as claimed in claim 1 , wherein the vacuum in the multilayer evaporator ( 4 ) is maintained by operation of the heat pump ( 5 ), and the absolute pressure for evaporation and separation in the multilayer evaporator ( 4 ) is 80-100 kPa.

3 . The process for continuous treatment of high-concentration organic wastewater as claimed in claim 1 , wherein the first preheater ( 7 ) performs heating by electric heating or electromagnetic heating with a heating temperature of 200-400° C.

4 . The process for continuous treatment of high-concentration organic wastewater as claimed in claim 1 , wherein the first desulfurizer ( 8 ) or the second desulfurizer ( 10 ) performs heating by electric heating or electromagnetic heating, the temperature for the desulfurization reaction is 200-400° C., and the internally filled desulfurizing agent thereof is zinc oxide, magnesium oxide, ferric oxide or calcium oxide.

5 . The process for continuous treatment of high-concentration organic wastewater as claimed in claim 1 , wherein the first catalytic combustor ( 9 ) or the second catalytic combustor ( 11 ) performs heating by electric heating or electromagnetic heating, the temperature for the purification reaction is 200-400° C., and the internally filled catalyst thereof is a platinum alumina catalyst, a platinum rare earth catalyst, a platinum silica catalyst or a platinum barium sulfate catalyst.

6 . A device used by the process for continuous treatment of high-concentration organic wastewater as claimed in claim 1 , wherein the device includes the feeding pump ( 1 ), the liquid flowmeter ( 3 ), the multilayer evaporator ( 4 ), the heat pump ( 5 ), the heat exchanger ( 6 ), the first preheater ( 7 ), the first desulfurizer ( 8 ) and the second desulfurizer ( 10 ) being parallelly arranged, as well as the first catalytic combustor ( 9 ) and the second catalytic combustor ( 11 ) being parallelly arranged; an upper inlet of the multilayer evaporator ( 4 ) is connected with the feeding pump ( 1 ) through the liquid flowmeter ( 3 ) by pipelines, the top outlet of the multilayer evaporator ( 4 ) is connected with an inlet of the first preheater ( 7 ) through the heat pump ( 5 ) and a cold fluid channel of the heat exchanger ( 6 ) by pipelines, an outlet of the first preheater ( 7 ) is divided into two paths, one path is connected with a top of the first desulfurizer ( 8 ) through a fifth valve ( 25 ) by pipelines, and the other path is connected with a top of the second desulfurizer ( 10 ) through a sixth valve ( 26 ) by pipelines; a bottom outlet of the first desulfurizer ( 8 ) is divided into two paths, one path discharges the regenerated tail gas through an eighth valve ( 28 ), and the other path is connected with a top of the first catalytic combustor ( 9 ) through a seventh valve ( 27 ) by pipelines; and a bottom outlet of the second desulfurizer ( 10 ) is divided into two paths, one path discharges the regenerated tail gas through a ninth valve ( 29 ), and the other path is connected with a top of the second catalytic combustor ( 11 ) through a tenth valve ( 210 ) by pipelines; and
an inlet of a hot fluid channel of the heat exchanger ( 6 ) is divided into two paths, one path is connected with a bottom outlet of the first catalytic combustor ( 9 ) through an eleventh valve ( 211 ) by pipelines, the other path is connected with a bottom outlet of the second catalytic combustor ( 11 ) through a fourteenth valve ( 214 ) by pipelines, and high-temperature steam outflowing from an outlet of the hot fluid channel of the heat exchanger ( 6 ) is used as a heat source to heat the multilayer evaporator ( 4 ); a pipeline between the bottom outlet of the first catalytic combustor ( 9 ) and the eleventh valve ( 211 ) is further connected with a first branch pipe in a through manner, and a twelfth valve ( 212 ) is arranged on the first branch pipe; and a pipeline between the bottom outlet of the second catalytic combustor ( 11 ) and the fourteenth valve ( 214 ) is further connected with a second branch pipe in a through manner, and a thirteenth valve ( 213 ) is arranged on the second branch pipe.

7 . The device used by the process for continuous treatment of high-concentration organic wastewater as claimed in claim 6 , wherein the device further includes a second preheater ( 12 ), air is introduced into an inlet end of the second preheater ( 12 ), and an outlet of the second preheater ( 12 ) is divided into four paths, which are respectively connected with a top inlet of the first catalytic combustor ( 9 ), a top inlet of the first desulfurizer ( 8 ), a top inlet of the second desulfurizer ( 10 ) and a top inlet of the second catalytic combustor ( 11 ) through a fifteenth valve ( 215 ), a sixteenth valve ( 216 ), a seventeenth valve ( 217 ) and an eighteenth valve ( 218 ) by pipelines.

8 . The device used by the process for continuous treatment of high-concentration organic wastewater as claimed in claim 6 , wherein multiple layers of evaporation heating trays are arranged in the multilayer evaporator ( 4 ) from top to bottom, heating pipes in the multiple layers of evaporation heating tra

Assignees

• Univ Zhejiang Technology

Inventors

• Nie Yong
• Yu Shangzhi
• Liang Xiaojiang
• Xie Qinglong
• Wu Zhenyu
• Bai Jianfeng

Classifications

• C02F2209/08

  Chemical Oxygen Demand [COD]; Biological Oxygen Demand [BOD] · CPC title

• C02F2209/03

  Pressure · CPC title

• C02F2101/101

  Sulfur compounds · CPC title

• C02F1/16

  using waste heat from other processes · CPC title

• C02F1/043

  Details · CPC title