Supercritical water oxidation treatment system for organic wastewater with high salinity

Patent metadata

Field	Value
Publication number	US-9328008-B2
Application number	US-201214396732-A
Country	US
Kind code	B2
Filing date	Dec 5, 2012
Priority date	Apr 23, 2012
Publication date	May 3, 2016
Grant date	May 3, 2016

Abstract

A supercritical water oxidation treatment system for organic wastewater with a high salinity crystallizes high-salinity wastewater by a low temperature of liquid oxygen, and decreases an inorganic salt content in the wastewater. Under supercritical water conditions, a hydrocyclone ( 4 ) separates most precipitated solid salts in the wastewater, so effectively prevents pipes and the tubular reactor ( 22 ) after the hydrocyclone ( 4 ) from plugging. Inorganic salts are able to be continuously separated from the system by the hydrocyclone ( 4 ) at the bottom of a desalination device, In addition, excess oxygen and gaseous products CO 2 are recovered by a separation recovery part. The reaction time and the reaction temperature of supercritical water oxidation reaction are lowered due to the installation of a simple post-treatment unit ( 37 ). Moreover, the heat of the reactor effluent with a high temperature is recovered in the system, so operation cost of the system is reduced evidently.

First claim

What is claimed is:

1. A supercritical water oxidation treatment system for organic wastewater with a high salinity comprising: a pre-desalination part, a supercritical water desalination part, a mix reaction part, and a separation recovery part:
wherein said pre-desalination part comprises a first tube heat exchanger and a second tube heat exchanger, wherein an inlet on a tube side of said first tube heat exchanger is injected with the wastewater with the high salinity, and an outlet on said tube side of said first tube heat exchanger is connected to an inlet of a cooling crystallization device, and a top outlet of said cooling crystallization device is connected to an inlet of a storage tank with organic wastewater, and a bottom outlet of said cooling crystallization device is connected to an inlet of a filter centrifuge, and a top outlet of said filter centrifuge is connected to said storage tank, and a bottom outlet of said filter centrifuge discharges salts; an glycol solution is injected through a shell side of said first tube heat exchanger and a shell side of said second tube heat exchanger, liquid oxygen is injected through an inlet on a tube side of said second tube heat exchanger;
said supercritical water desalination part comprises a heating furnace, an inlet of said heating furnace is connected to an outlet of said storage tank, and a middle outlet of said heating furnace is connected to an inlet of a hydrocyclone, and a top outlet of said hydrocyclone is connected to a middle inlet of said heating furnace, and an outlet of said heating furnace is connected to an inlet of a mixer, and then a bottom outlet of said hydrocyclone is connected to a desalination device;
said mix reaction part comprises a first volume heat exchanger, wherein an inlet on a tube side of said first volume heat exchanger is connected to an outlet on a tube side of a second volume heat exchanger, an outlet on said tube side of said first volume heat exchanger is connected to an inlet of a first buffer, an outlet of said first buffer is connected to an inlet of a mixer, an outlet of said mixer is connected to an inlet of a tubular reactor, an outlet of said tubular reactor is connected to an inlet on a tube side of a volume heat exchanger group;
said separation recovery part comprises a high-pressure gas-liquid separator, wherein an inlet of said high-pressure gas-liquid separator is connected to an outlet on said tube side of said volume heat exchanger group, and a top outlet of said high-pressure gas-liquid separator is connected to an inlet on a tube side of a fourth volume heat exchanger, and an outlet on said tube side of said fourth volume heat exchanger is connected to an inlet of a purification tower, and a top outlet of said purification tower is connected to an inlet of a second buffer, and an outlet of said second buffer is connected to an inlet of a high-pressure compressor, and an outlet of said high-pressure compressor is connected to said inlet of said first buffer; a bottom outlet of said high-pressure gas-liquid separator is connect to an inlet on a shell side of said first volume heat exchanger, and an outlet on said shell side of said first volume heat exchanger is connected to a post-treatment unit; an inlet on a shell side of said volume heat exchanger group is connected to a water softening device; an outlet on said shell side of said volume heat exchanger group outputs steam; an bottom outlet of said purification tower discharges CO 2 .

2. The supercritical water oxidation treatment system, as recited in claim 1 , wherein said water softening device comprises a softened water tank, and an outlet of said softened water tank is connected to said inlet on said shell side of said volume heat exchanger group through a low-pressure frequency conversion pump, and said outlet on said shell side of said volume heat exchanger group outputs the steam.

3. The supercritical water oxidation treatment system, as recited in claim 2 , wherein said volume heat exchanger group comprises two volume heat exchangers connected in series.

4. The supercritical water oxidation treatment system, as recited in claim 1 , wherein an buffer oxidizer is connected to said bottom outlet of said hydrocyclone, and a bottom outlet of said buffer oxidizer is connected to a top inlet of an expansion device, and a bottom outlet of said expansion device is connected to a top inlet of a salt storage pool, and a bottom outlet of said salt storage pool discharges inorganic salts.

5. The supercritical water oxidation treatment system, as recited in claim 1 , wherein said bottom outlet of said high-pressure gas-liquid separator is connected to said inlet on said shell side of said first volume heat exchanger through a back pressure valve, an unsealed liquid tank and a low-pressure water pump.

6. The supercritical water oxidation treatment system, as recited in claim 1 , wherein a sludge outlet end of said post-treatment unit is connected to said inlet of said storage tank through a linking pipe.

7. The supercritical water oxidation treatment system, as recited in claim 1 , wherein said outlet on said tube side of said first volume heat exchanger is also connected to said top inlet of said buffer oxidizer.

8. The supercritical water oxidation treatment system, as recited in claim 1 , wherein a top outlet of said buffer oxidizer is connected to said top outlet of said hydrocyclone.

Assignees

• Univ Xi An Jiaotong

Inventors

• Wang Shuzhong
• Xu Donghai
• Tang Xingying
• Gong Yanmeng
• Zhang Jie
• Wang Yuzhen

Classifications

• C02F1/20

  by degassing, i.e. liberation of dissolved gases (degasification of liquids in general B01D19/00; arrangement of degassing apparatus in boiler feed supply F22D) · CPC title

• C02F11/08

  Wet air oxidation · CPC title

• C02F5/00

  Softening water; Preventing scale; Adding scale preventatives or scale removers to water, e.g. adding sequestering agents (softening using ion-exchange C02F1/42) · CPC title

• C02F2001/5218

  Crystallization · CPC title

• C02F11/086 Primary

  in the supercritical state · CPC title