RU2607818C1 - System of waste waters zero waste disposal - Google Patents

Abstract

FIELD: water supply.

SUBSTANCE: invention relates to domestic waste water processing, namely, to system of waste waters zero waste disposal with their desalination and further supply to injection into gas transfer units gas-turbine plants for cooling of turbines. Waste water recycling system includes waste water biological or biochemical treatment unit (4), having treated effluent (14) outlet and sediment (20) outlet, sediment (20) composting unit (5), connected to sediment outlet, evaporation unit (7) for treated effluent (14) desalination, connected to treated effluent (14) outlet and having desalinated water (15) supply outlet and blowdown water (21) outlet, settling-crystallization unit (8) connected to blowdown water (21) outlet. At that, evaporation unit (7) desalinated water (15) supply outlet is made with possibility of communication with gas compressor unit gas turbine plant (10) cooling device (GCU GTP), installed with possibility of desalinated water injection into GCU GTP (10) path.

EFFECT: technical result is minimization of ambient environment pollution due to absence of recycling wastes, higher degree of waste water purification, decreasing power consumption for recycling, increasing in GCU GTP efficiency and power.

8 cl, 1 dwg

Description

The invention relates to the field of domestic wastewater treatment, and in particular to a system for waste-free utilization (use) of wastewater using their demineralization and subsequent supply to the gas turbine units of gas pumping units (hereinafter - GTU GPA) for cooling turbines.

The prior art there are many technologies for the treatment and disposal of wastewater using their demineralization (desalination) (see, for example, the application of the Russian Federation 94028714, 08/01/1994, US patent 4347704, 08.09.1982).

A known system for the disposal of wastewater from solid waste landfills, having an electrochemical treatment unit, a mechanical filtration and reverse osmosis separation unit, a water evaporation unit for its desalination (demineralization) and a salt crystallization unit (see RF patent 2207987, 07/10/2003, the closest analogue) .

A disadvantage of the known systems is that the treated effluent after demineralization is poured into the soil or into water bodies, which leads to environmental pollution.

The objective of the claimed invention is the creation of a wastewater disposal system that implements a safe and waste-free technology for the use of water.

The technical result of the invention is to minimize environmental pollution due to the absence of waste disposal, increasing the degree of wastewater treatment, reducing energy costs for disposal, increasing the efficiency and capacity of gas turbine compressor units and reducing the specific fuel gas consumption.

The specified technical result is achieved in the claimed system due to the fact that the waste-free waste water treatment system comprises: a biological or biochemical wastewater treatment unit having an outlet for treated effluent and an outlet for sludge, a sludge composting unit associated with the sludge outlet, an evaporation unit for demineralization of the treated effluent associated with the outlet of the treated effluent and having an outlet for supplying demineralized water and an outlet for purge water, a precipitation-crystallization unit associated with the outlet I backwash water, the outlet for supplying demineralized water evaporation unit is adapted to communicate with the cooling device a gas turbine plant installed with the possibility of injection of demineralized water into the gas turbine plant tract pumping unit (STU SBS).

In addition, the specified technical result is achieved in special cases of the invention due to the fact that:

- the biological or biochemical wastewater treatment unit includes a self-cleaning filtering device, averaging tank, a reagent treatment mixer, a settling tank, a biological reactor with attached microflora, an aeration mixer, a ruff filter, dosing and pumping stations, a disk filtration and disinfection device, and control and measuring devices and devices for automation of technological processes,

- the sludge composting unit includes a sludge dewatering device in the form of a screw dehydrator, or a filter press, or a centrifuge, and a composting platform,

- the evaporation unit contains low-temperature multi-section evaporators having evaporation sections and water condensation sections,

- the evaporation block contains a device for preheating water, while the system additionally includes utilization heat exchangers installed in the exhaust tract of the gas turbine engine and connected with the preheating device with the possibility of supplying secondary heat energy to it, - the evaporation block includes a line for supplying heated circulation water to thermal consumers energy and return line of chilled circulating water,

- the precipitation-crystallization unit contains a lime milk preparation unit, a settling tank with a sludge trap and baffles, flow quenchers, a collector for clarified water, a settling tank, an evaporation unit including an expander, a crystallizer, a circulation pump and a heater, as well as two alternately operating salt storage tanks,

- precipitation-crystallization unit is configured to precipitate gypsum, chalk, magnesium hydroxide and crystallization of sodium chloride and potassium chloride and other salts directed to useful use.

Unlike analogs in the claimed system, the output of demineralized water of the evaporation unit is connected to the GTU cooling device, by means of which demineralized water is injected into the GTU tract to cool it and evaporates into the atmosphere in the form of steam, while a composting unit is also provided in which the activated sludge after The biological or biochemical treatment unit is processed into a feed product or fertilizer.

The claimed invention is illustrated in FIG. 1, which shows a scheme for the disposal of wastewater using the claimed system.

Structural elements in the diagram are indicated by the following positions:

1 - pumping station

2 - water treatment plants,

3 - water consumers,

4 - block biological or biochemical wastewater treatment,

5 - composting unit,

6 - thermal complex for demineralization of water,

7 - evaporation unit of the thermal complex,

8 - precipitation-crystallization block of the thermal complex,

9 - consumers of secondary thermal energy,

10 - GTU GPA.

Process flows are indicated by the following positions:

11 - source of natural water from a water source,

12 - water for water use,

13 - wastewater

14 - purified stock,

15 - demineralized water for injection into a gas turbine,

16 - water vapor into the atmosphere,

17 - water from the atmosphere with precipitation (rain, snow, fog, hail),

18 - heated circulation water for use by consumers,

19 - cooling cooling water, including useful used for the production of demineralized water,

20 - sediment biological or biochemical treatment for composting,

21 - purge water of the evaporation block,

22 - precipitate of the thermal complex in the form of compounds: gypsum, chalk, magnesium hydroxide for use in the manufacture of building materials,

23 - sediment thermal complex in the form of crystallized salts of NaCl, KCl and others for use in the processing of roads (for example, in winter),

24 - secondary thermal energy of the heat of the exhaust gases of GTU GPA,

25 - summed up from the outside thermal energy used when there is a lack of flow of thermal energy 24.

The claimed system includes a unit (4) for biological or biochemical wastewater treatment from consumers (3), a unit (5) for composting sludge obtained during biological or biochemical treatment, a thermal complex (6) for demineralization, which has an evaporation unit (7) for demineralization of the treated effluent and a precipitation-crystallization unit (8) for collecting sediment from the purge water of the evaporation unit (7), as well as a GTU cooling device (10) for injecting demineralized water into the GTU turbine (10).

The biological or biochemical treatment unit (4) is a complex of sewage facilities and may include without limitation a self-cleaning filtering device, averaging tank, a reagent treatment mixer, a settling tank, a biological reactor with attached microflora, an aeration mixer, a ruff filter, dosing and pumping stations, disk filtering and disinfection device, instrumentation and technological automation devices. The block (4) of biological or biochemical treatment has an inlet for supplying wastewater (13) from consumers and may also additionally have an entrance for purified water (12) from a natural source that has passed treatment plants (2) (treatment plants may or may not be included composition of the claimed system). In addition, the unit has an outlet for spent sludge (sludge) (20) and treated effluent (14).

The composting unit (5) is connected to the sludge outlet (20) of the block (4) and may contain sludge dewatering devices (a screw dehydrator, or a filter press, or a centrifuge) and a composting platform on which the sludge is processed.

The evaporation block (7) of the thermal complex (6) is connected to the outlet of the cleaned drain (14) of the block (4). The evaporation unit may include a water heating device that uses the secondary energy of the exhaust gas of the gas turbine (10), as well as a number of separate low-temperature multi-section evaporators having evaporation sections and water condensation sections. In addition, the evaporation block (7) may additionally include a supply line of heated circulating water (18) to consumers (9) of thermal energy (heating networks, hot water supply devices, snow melting devices, etc.) and a return line to the cooling circulating block (7) water (19). The evaporation unit has an outlet for purge water (21) and an outlet for demineralized water (15).

The precipitation-crystallization block (8) of the thermal complex (6) is designed to separate precipitation from the purge water (21) of the block (7) in the form of precipitation of gypsum, chalk and magnesium hydroxide and salts (22) (sodium and potassium chlorides). Precipitation-crystallization unit (8) may include a lime milk preparation unit, a settling tank with a sludge trap in the lower part, with baffles, flow quenchers, and a collector for collecting clarified water in the upper part, a settling tank, and also an evaporation plant consisting of an expander, a crystallizer, a circulation pump and a heater, as well as two alternately working salt storages. The expander and crystallizer are cylindrical vessels with a conical bottom.

In addition, the thermal complex may include pumping stations, reagent dosing plants, instrumentation and technological automation devices.

The GTU cooling device (10) is designed to supply demineralized water (15) from the evaporation block (7) to the GPU gas turbine path (10) for its cooling. The device may be a demineralized water injection means (15).

The claimed system may also additionally include recycling heat exchangers (not shown in the drawings) installed in the exhaust tract of a gas turbine and acting as a head heater. Moreover, these heat exchangers are connected with the evaporation unit (7) with the possibility of supplying secondary thermal energy (24) to the specified unit (7) for heating water for demineralization.

The process of non-waste water use using the claimed system is as follows.

The flow of source water (11) from a natural water source (underground or surface) comes from the pumping station (1) to the water treatment plant (2), from where it is directed for water use (12) to consumers (3), resulting in a wastewater stream ( 13).

Wastewater (13) is sent to the sewage treatment plant in a biological or biochemical treatment unit (4). If necessary, part of the wastewater stream (13) can be returned to the water treatment plant (2). In addition, part of the flow for water use (12) from treatment plants (2) can be supplied to block (4). After passing the full cycle of biological or biochemical treatment, the treated effluent (14) is sent to the evaporation unit (7) of the thermal complex (6), and the precipitate (20) is sent to the composting unit (5). In the composting unit, the sludge (spent activated sludge) is dried (if necessary), mixed with fillers (municipal solid waste, peat, sawdust, foliage, straw, ground bark or prepared compost) and aged for processing. The resulting composted sediment is subsequently used as a feed product for fish in fish farms or as fertilizer in agriculture or in landscaping in urban utilities.

In the evaporation unit (7), the purified water (14) is evaporated, followed by condensation of demineralized water (15).

For the efficient operation of the evaporation unit (7), cooling cooling water is used, which can be used as source water (11), purified effluent and a stream of useful secondary heat energy used by consumers of heated circulation water. To do this, circulate the heated water through the evaporation block (7), in which the heated circulating water (18) is supplied to consumers (9) of thermal energy, and the cooled circulating water (19) is returned to the evaporation block (7), where it again performs useful work, simultaneously warming up. At the same time, a part of the source water stream (11) can be additionally supplied to the evaporation unit, bypassing the water treatment station. Depending on the technological needs, both the feed water of the circulation water circuit (lines 18 and 19) can be used, as well as the source water (11) for the demineralization process in case of insufficient volume of treated effluents (14). For the operation of the evaporation unit, thermal energy (24) of the heat of the exhaust gases of the gas turbine unit (10) and / or thermal energy (25) supplied from the outside can be used.

The purge water (21) of the evaporation block is sent to the precipitation-crystallization block (8), where the products are deposited (22) in the form of gypsum, chalk, magnesium hydroxide, which can be used for the production of building materials or in road construction, as well as crystallization salts (23) (NaCl, KCl and others), which can be used to prepare reagents for treating roads in winter.

When sedimentation is carried out in the lower part of the sump, a tangential supply of purge water is carried out, and after the introduction of water, dosing of milk of lime is performed. The tangential introduction of water provides intensive mixing of the solution and helps to accelerate the crystallization and precipitation of calcium and magnesium salts. Due to the transition of the conical part to the cylindrical part, as well as the presence of flow dampers, the flow calms down, the crystallized sludge drops down, and the clarified water gradually rises and the evaporator cycle returns through the collector. At the same time, the sludge containing calcium and magnesium salts goes down and is drained into the settling tank, where its deposition is completed, additional clarified water is removed, and the sludge is taken for useful use.

Water from the evaporator concentrate zone is fed through the heater to the expander, where boiling occurs, and from where steam is again discharged to the evaporator, and pre-concentrated water enters the crystallizer, in which, by choosing the operating mode, the salt solution is maintained in the solution saturated zone, due to which in particular, the equipment is protected from fouling with salts, and their deposition occurs with crystal sizes of at least 1 mm. From the crystallizer, the pulp of salts enters alternating salt storage tanks, in which residual salt deposition occurs, the weakly concentrated solution is again diverted to the crystallization cycle, and the wet precipitated crystallized salts are periodically taken from the salt storage tanks for their useful use.

The process of concentration and evaporation of sodium, potassium and other salts contained in the source water and, accordingly, in the purge water of the evaporators of the thermal complex, is as continuous as the sedimentation process.

Demineralized water (15) enters the GPU GPU cooling device (10), which injects water into the turbine path, which brings its operation to normal operating conditions, as a result of which the efficiency and available power are increased, while the specific consumption of natural gas is reduced, and emissions are reduced NOx and reduces thermal pollution of the atmosphere. Injected demineralized water (15) evaporates and enters the atmosphere in the form of water vapor (16) with exhaust gases and then, due to natural condensation processes in the form of precipitation (rain, snow, fog, hail), returns to the water source for its subsequent useful use.

Thus, the claimed system provides waste-free and waste-free disposal of wastewater, as well as improving the efficiency and capacity of gas turbine engines.

Claims (13)

1. A wastewater disposal system comprising: - a unit (4) for biological or biochemical wastewater treatment, having an outlet for treated effluent (14) and an outlet for sludge (20), - block (5) composting sediment (20) associated with the release of sediment, - an evaporation unit (7) for demineralizing the treated effluent (14) associated with the outlet of the treated effluent (14) and having an outlet for supplying demineralized water (15) and an outlet for purge water (21), - precipitation-crystallization block (8) associated with the outlet for purge water (21), the outlet for supplying demineralized water (15) to the evaporation block (7) is made with the possibility of communication with the cooling device of the gas turbine unit (10) of the gas pumping unit (GTU GPA) installed with the possibility of injection of demineralized water into the path of the GTU GPU (10). 2. The system according to claim 1, in which the unit (4) of biological or biochemical wastewater treatment includes a self-cleaning filter device, averaging tank, a reagent treatment mixer, a settling tank, a biological reactor with attached microflora, an aeration mixer, a ruff filter, dosing and pumping stations, disk filtration and disinfection device, instrumentation and technological automation devices. 3. The system according to claim 1, in which the sludge composting unit (5) includes a sludge dewatering device in the form of a screw dehydrator, or a filter press, or a centrifuge and a composting platform. 4. The system according to claim 1, in which the evaporation unit (7) contains low-temperature multi-section evaporators having evaporation sections and water condensation sections. 5. The system according to claim 4, in which the evaporation unit (7) contains a device for preheating water, while the system additionally includes utilization heat exchangers installed in the exhaust tract of the gas turbine engine (10) and connected with the preheater with the possibility of supplying it with a secondary thermal energy (24). 6. The system according to claim 4, in which the evaporation unit (7) includes a line for supplying heated circulating water (18) to consumers (9) of thermal energy and a return line for cooled circulating water (19). 7. The system according to claim 1, in which the precipitation-crystallization unit (8) contains a lime milk preparation unit, a settling tank with a sludge trap and baffles, flow quenchers, a collector for collecting clarified water, a settling tank, an evaporation plant including an expander, a crystallizer, circulation pump and heater, as well as two alternately working salt storage. 8. The system according to claim 7, in which the precipitation-crystallization unit (8) is configured to precipitate gypsum, chalk, magnesium hydroxide and crystallize sodium chloride and potassium chloride.

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