KR20020011041A - A method and equipment for regeneration and separate recovery of waste water, waste absorbent, waste absorbent oil and waste organic solvent etc. which have been involved odor and VOCs. - Google Patents

Abstract

PURPOSE: A regeneration and separation method of wastewater, waste adsorbent, waste adsorbing oil and waste organic solvent containing odor and VOCs is provided, which control more than 90 % of odor and VOCs which were re-evaporated in conventional process and recover useful components contained in waste gas by vacuum evaporation at ambient temperature. CONSTITUTION: The recovery equipment comprises three vacuum heated waste liquid regenerating tanks(14) which are set in parallel, two oil-less vacuum pumps(1,20), a pressurized condenser(25), a heater(12) and heat exchangers(15). Waste liquid is fed to the vacuum heated waste liquid regenerating tank(14) that is kept at vacuum of 0 to 70 Torr by one oil-less vacuum pump(1) controlled by a solenoid valve(5) and is heated by condensing heat of desorbed matter to ambient temperature to 200 deg.C. The other oil-less vacuum pump(20) compress to pressurized condenser(25) that is controlled by a pressure control valve(23) and condense.

Description

A method and equipment for regeneration and separate recovery of waste water, waste absorbent, waste absorbent oil and waste organic solvent etc which have been involved odor and VOCs.}

The present invention relates to a method and apparatus for separating and regenerating waste organic solvent during waste treatment, wastewater containing odors and VOCs substances in waste absorbing liquid, waste absorbing oil and wastewater treatment in the field of air pollution control among environmental engineering.

In the conventional technology, in the field of air pollution control, waste absorbent liquid generated when odor or VOCs gas is treated by absorption method is introduced into the wastewater treatment plant and chemical oxidation, physical treatment condensation precipitation or flotation separation, biological treatment method, etc. And waste absorbent oil has not been applied due to the fact that no on-site treatment method for the appropriate waste liquid has been developed.

Odors and VOCs-causing substances contained in the wastewater are currently sealed in the wastewater treatment plant and the gas collected using the hood on the wastewater treatment plant is treated with activated carbon existing odor and VOCs treatment method.

In the case of waste organic solvents, organic solvents are collected by waste distillation companies, fractionally distilled, and sludge is disposed of separately.

Disadvantages of conventional malodorous and VOCs containing absorbent treatment methods

① Because most substances are physically dissolved at low solubility, a considerable amount of absorbed substances are degassed during treatment and discharged back into the atmosphere.

② In addition, if there is no existing wastewater treatment plant, a separate wastewater treatment plant should be created and operated.

③ Economical losses and sludge-type waste disposal costs are added by treating useful raw materials contained in the waste absorbent.

In the case of treating pollutants in the exhaust gas using absorbent oil, waste absorbent oil has to be transported to a refinery to be re-distilled or disposed of as waste.

Odor and VOCs substances contained in the wastewater are discharged to the atmosphere at the operating pressure of the substance from the wastewater generation to the end of the treatment.The existing method covers the entire wastewater treatment plant to capture the exhaust gas and collect the exhaust gas. It is treated by the air pollution treatment method. As a result, expensive cover and prevention facility installation and maintenance costs are being consumed.

Waste organic solvents are collected as liquid wastes and incinerated in liquid waste incinerators, or used as auxiliary fuels for waste incinerators, and some are collected, fractionally distilled and recovered for reuse in thinners. In this case, the method of incineration has the disadvantage of using toluene, xylene, isopropyl alcohol, etc., which are useful raw materials included in the waste organic solvent, as a simple heat source. And fractional distillation at high temperature in the recovery process may have safety problems.

An object of the present invention is to improve the conventional treatment method of wastewater, waste absorbent liquid, waste absorbent oil, waste organic solvent to create a new chapter of the treatment of odor and VOCs

① The wastewater and waste absorbents in which odors and VOCs are dissolved are simply treated on-site, and the odors and VOCs-causing substances contained therein are removed and recovered, and the wastewater is the wastewater treatment process excluding odors and VOCs. Make it reusable

② When absorbent oil is used instead of absorbent liquid to treat odors and VOCs, waste absorbent oil can be recycled simply on site instead of being sent to the refinery process, regeneration plant and liquid waste to enable continuous use of absorbent oil. Recover and increase your economics.

③ In the case of the waste organic solvent, the efficiency of resource recovery is improved by simply regenerating and reusing the site at low temperature by controlling the boiling point by adjusting the vacuum pressure.

④ In this case, the material contained in the waste liquid can be recovered according to the properties according to the physical properties to reduce the raw materials

⑤ No secondary pollution problems such as waste water, waste absorbent liquid, waste absorbent oil, waste organic solvent, etc.

⑥ It is possible to secure an economical comparative advantage in terms of installation cost, maintenance cost, convenience, etc.

⑦ To provide an ideal method of treating odors and VOCs that can separate and recover useful substances from waste liquids containing odors and volatile organic compounds (VOCs) and regenerate waste liquids.

FIG. 1 is a representative process and device diagram of a method for continuously regenerating waste liquid and separating and recovering absorbed material according to a first embodiment of the present invention. Apparatus and each detailed apparatus diagram consisting of vacuum heating waste liquid regeneration tank, oilless vacuum pump, pressurized condenser or pressurized tank

FIG. 2 is an apparatus diagram of a pressurized tank which is a pressurized absorbent material recovery method replacing the pressurized condenser of FIG.

[Explanation of symbols on the main parts of the drawings]

1: Oilless Vacuum Pump 2: Waste Liquid Transfer Pump

3: solenoid valve for pressure regulation 4: check valve

5: solenoid valve 6: agitator and stirring motor

7: solenoid valve 8: level gauge

9: digital vacuum gauge 10: waste liquid inlet

11: flow control valve 12: heating heater

13: temperature sensor 14: vacuum heating waste liquid regeneration tank

15 heat exchanger for vacuum tank heating 16 solenoid valve

17: treatment waste liquid outflow 18: flow sensor

19: pressure regulating valve 20: coolant circulation pump

21: Control Panel 22: Supplying fresh water

23 pressure control valve 24 non-condensing gas outlet

25: pressurized condensate recovery unit 26: control panel

27: temperature sensor 28: recovery liquid storage tank

29: pressure control valve 30: unrecovered gas outlet

31: pressure regulating valve 32: level gauge

33 pressure gauge 34 coolant outlet

35 pressurized condensation tank 36 heat exchanger for recovery tank cooling

37: level gauge 38: coolant inlet

39: solenoid valve for recovery liquid discharge 40: flow sensor

41: Recovery liquid outlet 42: Odor and VOCs recovered under reduced pressure

43: oilless vacuum pump

As a representative treatment process and apparatus diagram of the present invention for achieving the above object, the process configuration for the continuous recovery of odors and VOCs-containing waste liquid and separate recovery of the absorbed material is vacuum vacuum waste waste regeneration tank 14, oilless vacuum pump ( 20), a pressure condenser 25 or a pressure condensation tank 35.

Specifically, in FIG. 1, the vacuum warmed waste regeneration tank 14 has a structure capable of high vacuum and warming, in which one or more units are connected in parallel, and the waste liquid 10 is sequentially transferred to the vacuum warmed waste regeneration tank 14. After decompression using oilless vacuum pumps (20, 44) at the appropriate pressure, and heated (12, 15) at the same temperature according to the type of material to be recovered, the waste liquid can be recovered and separated for each material and used continuously. It would be.

In addition, the separated material is reduced to below room temperature in the pressure condenser 25 connected to the rear end of the vacuum pump, and the pressure control valve 23 is installed at the rear end of the condenser to maintain the pressure inside the condenser above atmospheric pressure. Condensation and recovery by compression were made possible using a pressurized condensation tank 35 capable of condensation recovery or heat reduction with a heat exchanger 36.

Each detailed apparatus is composed of a vacuum heated waste liquid regeneration tank 14 to the respective tanks 14 using the transfer pump 2 while the pressure control valve 3 is opened at the waste liquid inlet 10. The solenoid valve 5 and the level gauge 8 are used to transfer sequentially.

When the transfer is completed, the oilless vacuum pump (1) is closed with the solenoid valves (5, 16) and the pressure regulating valves (3) of the waste liquid inlet and outlet closed and the check valve (4) and the solenoid valve (6) open. The vacuum gauge 9 is used to reduce the pressure of the inside of the tank 14 to an appropriate degree of vacuum. At the same time, the condensation heat radiated from the condenser 25 or the pressurized tank 35 is used as the main heat source, and as the auxiliary heat source, the tank (using the heat fluid heated using the heating device 12 for heating the cooling water or the heat fluid and the refrigerant) 14) To prevent the internal temperature drop due to the heat of vaporization when the temperature rises and desorptions inside, by installing a heat exchanger 15 to raise or maintain the temperature above the boiling point of the material contained in the waste liquid to vacuum evaporate the substance contained in the waste liquid Recover. At this time, the temperature control of the thermal fluid is controlled by the temperature sensor 13 and the thermal fluid pump 20 and equipped with a stirrer and a stirring motor 6 in each tank to promote boiling.

After the regeneration and recovery is completed, the regenerated waste liquid is opened by the pressure regulating valve (3) to control the internal pressure, and is absorbed by the solenoid valve (16), the line flow sensor (18), and the transfer pump (21). scrubber) and waste water treatment plant.

All or part of the apparatus is installed in the regeneration tank, and the control panel is automatically controlled.

In the method of separating and recovering the desorbed material, an oilless vacuum pump (1, 43) is installed to condense the condenser (25) or a pressurized condensation tank by atmospheric pressure or pressurization of the recovered material using the pressure regulating valves (23, 29, 31). Recover to (35).

The condensation heat generated at this time is a pressurized condensation in which a circulation pump 20, a pressure control valve 19, a supply line 22, and a condenser 25 or a heat exchanger 36 are provided to supply and circulate cooling water, a thermal fluid or a refrigerant. The tank 35 is cooled and at this time, the uncondensed gas is returned to the air pollution prevention facility inlet through the pressure regulating valves 23, 29, and 31, and is reprocessed. 23) is installed in the condenser 25, the pressure condenser tank 35, the pressure gauge (29, 31) for the uncondensed gas recirculation and pressure recovery rate adjustment, the pressure sensor 33 for safe operation, the titration of the recovery liquid A level gauge 32, a solenoid valve 39, and a line flow sensor 40 for discharge are attached to the pressurized condensation tank 31, respectively. All or part of the above sensors and devices are installed and characterized in that they are automatically controlled from their control panel.

The advantage of the present invention is that when applied to the waste absorbing liquid discharged from the treatment method by the absorption in the existing air pollution prevention facilities can reduce the odor and VOCs emissions evaporated and discharged again in the existing wastewater treatment process by more than 99% Among the substances contained in them, almost all of the substances absorbed in the absorbent liquid can be recovered in a liquid state and can be reused as raw materials to further increase the economic efficiency.

In addition, the treatment method of the present invention enables the development and field application of low molecular weight low boiling point odors and VOCs substances (Oil scrubber) to liquid high molecular weight hydrocarbon materials, and odor among waste absorbing oils generated in this case. And VOCs are separated by vacuum heating, evaporation, condensation and recovery, and absorbed oil is recycled to the prevention facility.

When applied to wastewater treatment plants containing odors and VOCs substances, this equipment is installed as a pretreatment facility in wastewater treatment plants to separate and recover the odors and VOCs substances contained in the original wastewater by vacuum heating and evaporation. VOCs emissions can be significantly reduced, and the need for cover and hood duct construction and air pollution prevention facilities in existing wastewater treatment plants can be eliminated.

When applied to waste organic solvents, only organic solvents, excluding impurities, are recovered by vacuum evaporation at room temperature to be recovered and reused as raw materials, thus saving the raw materials and reducing waste generation.

As described above, the application facilities of the present invention include an on-site regeneration facility for waste absorbing liquid generated during the absorption treatment of odors and VOCs in an aqueous solution state, development of a method for absorbing low molecular odors and VOCs in liquid polymer hydrocarbons, and In this case, the absorbent liquid can be recycled and recycled on site, and the odor and VOCs substances contained in the exhaust gas can be recovered in the liquid phase.

When applied to wastewater treatment plants, it can be applied as a pretreatment facility to all wastewater treatment plants that emit odors and VOCs in the inflow state, and can replace the installation of air pollution prevention facilities at a later stage. The organic solvents contained in the waste organic solvent can be recovered and reused and the impurities can be discharged to the sludge.

Claims (8)

In order to regenerate sorbents containing odors and volatile organic compounds (VOCs), waste water, and waste absorption oil (hereinafter referred to as waste liquid), the waste liquid is put into a vacuum waste liquid regeneration tank 14 and oil A waste liquid vacuum regeneration method characterized by separating the odors and VOCs substances contained in the waste liquid with a vacuum of 0 to 70 Torr with a lease vacuum pump (1). The solenoid valve (5, 16) for maintaining the internal vacuum at the inlet and the outlet and transporting the waste liquid in the waste liquid vacuum heating waste liquid regeneration tank (14), the pressure gauge (9) for controlling the degree of vacuum in the tank, and the vacuum pump titration Solenoid valve (6) for operation, check valve (4), solenoid valve (3) for pressure adjustment inside the tank connected to the uncondensed gas recovery line, internal stirrer and stirring motor (6) to promote the vaporization of waste liquid, waste liquid transfer The waste liquid vacuum regeneration device, characterized in that all or part of the transfer pumps (2, 21), the level gauge (8), the flow sensor (18) for waste liquid transfer adjustment are automatically controlled by the control panel. The waste absorbing liquid and the waste absorbing liquid in the vacuum warmed waste liquid regeneration tank 14 to recover the absorbent liquid containing odor and volatile organic compounds (VOCs), waste water, waste absorption oil (hereinafter referred to as waste liquid) on-site. The waste liquid was put into a vacuum of 0-70 Torr with an oilless vacuum pump (1), and the odor and VOCs substances contained in the waste liquid were separated by heating between room temperature and -200 ° C using the heat of condensation discharged upon condensation of desorbed material as a main heat source. Waste liquid vacuum heating and regeneration method, characterized in that for The solenoid valve (5, 16) for maintaining the internal vacuum at the inlet and the outlet and transporting the waste liquid from the waste liquid vacuum heating waste liquid regeneration tank (14), the pressure gauge (9) for adjusting the degree of vacuum in the tank, and the vacuum pump titration Solenoid valve (6) for operation, check valve (4), solenoid valve (3) for pressure adjustment inside the tank connected to the uncondensed gas recovery line, internal stirrer and stirring motor (6) to promote the vaporization of waste liquid, waste liquid transfer Transfer pumps (2, 21), level gauge (8), flow sensor (18) for waste liquid transfer control, thermometer (13), temperature condensate recovery (25) or pressurization All or part of the heat exchanger 15, the flow control valve 11, the auxiliary heating 12 for heat exchange with the condensation tank 35 is installed and automatically controlled by the control panel sequentially Waste fluid vacuum Warming regeneration device Pressure control valves (23, 29, 31), uncondensed gas at the rear of the oilless vacuum pump (1) to recover odors and volatile organic compounds (VOCs) desorbed from the waste liquid vacuum heated regeneration tank (14). By installing a pressure condensation recovery unit 25 or a pressure condensation tank 35 with a heat exchanger for mutual heat exchange with the recirculation line and the regeneration tank 14 to recover the separated material from the regeneration tank 14 Odor and VOC condensation recovery method. 6. The pressurized condenser 25 or the pressurized condensation tank 35 is operated under the condition of relative atmospheric pressure -0.5 atm, and the uncondensed gas is connected to the front end of the air pollution prevention facility and reprocessed, and the condensation heat is heated in the vacuum of the waste liquid. Odor and VOC material condensation recovery apparatus characterized in that the cooling by heat exchange with the heat of vaporization when the regeneration tank (14). In claim 5, the level sensor 32 for detecting the water level of the main body in the pressurized condensation tank 35, the solenoid valve 39 for the discharge of the recovery liquid, the flow sensor 40, the temperature sensor 33 for adjusting the internal temperature And odor and VOC substances characterized by automatically controlling the discharge of the condensed and recovered liquid by the control panel and the pressure control valves 29 and 31 equipped with an uncondensed gas outlet for controlling the pressure of the tank 35. Pressurized condensation recovery unit. In order to separate and recover the useful solvent components of the waste organic solvent by boiling point, the attained vacuum degree is sequentially adjusted by using a vacuum gauge (9), and the internal temperature is controlled by using a temperature gauge and a heating heater (12). Separation and recovery method for each of the solvent components of the waste organic solvent, characterized in that sequentially separating up to a high boiling point material and condensed recovered by the condensation recovery device (25) or pressure condensation tank (35) device.