RU170034U1 - Make-up water preparation system for boiler or power plant circuits with combined generation of electric and thermal energy - Google Patents

Abstract

Field of technology: water treatment. Essence: make-up water treatment system for boiler or power plant circuits with combined generation of electric and thermal energy (CHP), including a mechanical treatment unit (UMO) of 5 source water and contaminated return condensate (CIR); mixing unit (CSS) 1 of the source water and air-conditioning system equipped with a mixing tank (SB) 2; installation of reverse osmosis (UOE). Distinctness: UMO 5 is made in the form of a single unit located between US 1 and the specified UOE. The system may additionally contain a temperature controller (RT) 16 of the mixture of the source water and the CIC with a temperature sensor (DT) 17 at the inlet of the specified water mixture in the DOE and with two actuators, one of which is made in the form of a control valve (RC) 18 on line 3 supply to the CSS 1 of the source water, and the other in the form of a source water heater (NIV) installed on the same line 19. Technical result: a complete combination of the source water purification means and the contaminated return condensate, which reduces the units of installed equipment Ania, simplifying operation and reducing installation necessary for her industrial areas. 3 s.p. f-ly, 2 ill.

Description

Technical field

The utility model relates to the field of water treatment and can be used for the preparation of make-up water in boiler rooms and at combined heat and power plants (CHP) with combined generation of electric and thermal energy in steam-turbine or combined-cycle power (PTU, CCGT) plants.

State of the art

A well-known system of separate preparation of makeup water and purification of contaminated return condensate for boiler or power plant circuits with combined generation of electric and thermal energy (V. 2. Typical water circulation schemes in TPP and NPP cycles / Encyclopedia of Mechanical Engineering, Volume XXI, 2015 // http: //twt.mpei.ac.ru/books/vve/intro_2_pg1.htm [1] - analogue).

The disadvantage of this system is the need to create separate technological lines for treating make-up water, which compensates for the loss of return turbine condensate, and return contaminated condensate of industrial steam, which significantly complicates the operation of the system, significantly increases the need for production facilities and the capital cost of equipping two independent production lines.

A known system of integrated membrane technology, including the installation of mechanical (ultrafiltration) treatment (UMO) installation.

A system of integrated membrane technology is known, including a mechanical (ultrafiltration) treatment unit (UMO), a reverse osmosis desalination unit (UOE) with two treatment stages (UOO-1 and UOO-2), and an electrodeionization unit (UED).

The specified integrated training system produces make-up water at the CHPP for boiler circuits, heat supply systems (STS) and for the circulation cooling of steam turbine condensers. Depending on the requirements for the quality of make-up water for these circuits, purified water is discharged after UOO-1 or UOO-2 or UED.

In addition, the main water treatment plants at the CHPP include an autonomous desalination plant (AOU).

In analogue [2], there is provided a mixing tank (SB) of condensate after AOU with the source water, installed on the deep desalinated water path after EDR (Technological solutions of modern water treatment systems, part 1. / A.A. Panteleev, B.E. Ryabchikov, O .V. Khoruli, E.R. Kalendarev // http://www.medfilter.ru/kh32.html [2] - analogue).

The specified AOU includes a contaminated condensate collection tank (BPC), a contaminated condensate heat exchanger-cooler, a mechanical cleaning filter and ion-exchange H-OH desalination filters with a desalted condensate supply line to the condensate stock tank.

The disadvantage of this system, as well as in the analogue [1], is the need to create separate technological lines for treating make-up water, which compensates for the loss of return turbine condensate and return contaminated condensate.

Another disadvantage of this system is the use of commercial acid and alkali for the regeneration of AOU filters and, accordingly, the need to create an acid-base economy and a unit for neutralizing the waste water of AOU. This drawback is in clear contradiction with the integrated membrane technology for the preparation of make-up water at TPPs that do not use acid and alkali.

Another disadvantage of this system is the need to cool contaminated condensate with a temperature of 96-98 ° C to 35-40 ° C before being fed to the AOC due to the inability of the anion exchange resin to work at a higher temperature.

The disadvantages of the analogue [2] should also include the need for the conditions of the AOU installation of a large-capacity BZK installation (650-1000 m ³ ) and the quality limit of the contaminated condensate supplied to the AOU for iron <300 μg / dm ³ and for silicic acid <300 μg / dm ³ above which condensate is drained into the sewer.

A known system for the preparation of make-up water for the circuits of a boiler house or power plant with combined generation of electric and thermal energy, including:

- separate ULV source water and contaminated return condensate;

- mixing unit (CSS) of the source water and the contaminated return condensate, equipped with a mixing tank (SB), located after the specified installations of mechanical treatment of the source water and condensate;

- UOO.

(Creation of a water treatment system for a combined cycle power plant in Noyabrsk (Yamal-Nenets Autonomous Okrug) - the first example of the use of integrated membrane technology in domestic energy / NPK Mediana-filter 2010 http://www.medfilter.ru/kh32.html [3] - prototype).

The disadvantages of the prototype [3] include the use of separate ULV on the lines of source water and contaminated return condensate.

Utility Model Disclosure

The objective of the utility model is to reduce capital costs for equipment of a combined make-up water treatment system, and the technical result is a complete combination of the source water purification and contaminated return condensate, reducing the number of installed equipment, simplifying the operation of the installation and reducing the production space required for it.

The solution of this problem by achieving the specified technical result is ensured by the fact that in the make-up water preparation system for boiler or power plant circuits with combined generation of electric and thermal energy, including:

ULV source water and contaminated return condensate;

US source water and contaminated return condensate, equipped with SB;

UOO,

according to the utility model, the specified ULV of the source water and the contaminated return condensate is made in the form of a single unit located between the specified CSS and DO.

A causal relationship between the set of essential features of the patented utility model and the indicated technical result is that the installation of mechanical cleaning of the source water and the contaminated return condensate in the form of a single unit located between the mixing unit and the reverse osmosis installation simplifies the operation of the installation and reduces necessary production facilities for it.

Brief Description of the Drawings

In FIG. 1 shows a block diagram of a make-up water preparation system according to examples 1 and 2 of a utility model for a TPP with a vocational school; in FIG. 2 - the same for example 3 of the implementation of the utility model in relation to the boiler room.

Legend

AOU - autonomous desalting plant;

BZK - tank of contaminated condensate;

BK - tank concentrate UOO or UED;

BP - tank permeate UOO-1;

VPU - water treatment plant;

D is a decarbonizer;

DT - temperature sensor;

W - rigidity;

NIV - source water heater;

OSG - irrigation of "dry" cooling towers;

PTU - combined-cycle plant;

PC - steam boiler;

PTU - steam turbine installation;

RK - control valve;

RT - temperature controller;

SB - mixing tank of source water with contaminated return condensate;

SG - “dry” cooling tower;

STS - heat supply system;

TPP - cogeneration plant;

UMO - installation of mechanical cleaning;

US - node mixing source water and contaminated return condensate;

UOO - reverse osmosis installation;

UED - installation of electrodeionization;

Щ - alkalinity

List of drawing items

1 - CSS; 2 - SB; 3 - supply line to the source of source water; 4 - BZK; 5 - ULV; 6 - UOO - 1; 7 - PSU; 8 - feed water supply line to the SG irrigation circuit; 9 - feed water line to the STS; 10 - feed line permeate UOO-1 in UOO-2; 11 - UOO-2; 12 - D; 13 - UED; 14 - BC UOO-1; 15 - feed line of concentrate UOO-1 for loosening the washing of the filter layer of the filter UMO; 16 - RT; 17 - DT; 18 - RK; 19 - NIV; 20 - BC UOO-2; 21 - line for the discharge of concentrate from BC 20; 22 - BC UED; 23 - line discharge concentrate from BC 22.

Utility Model Implementation

The make-up water preparation system for boiler or power plant circuits according to the utility model includes (Fig. 1 and 2) a mixing unit US 1 equipped with a mixing tank SB 2, a supply line 3 to the US 1 source water and a tank BZK 4 for collecting and supplying to SB 2 contaminated return condensate of industrial steam.

In the course of the technological process, the patented system also contains a mechanical treatment unit UMO 5 and a two-stage (Fig. 1) UOE with the first stage UOU-1 6 (Figs. 1 and 2) equipped with a tank of purified water (permeate) BP 7. Three are connected to the last drainage lines of said permeate from it: line 8 (Fig. 1) of feed water to the irrigation system of the so-called “dry” cooling towers (SG), in which cooling water circulates inside the heat exchange pipes; line 9 (Fig. 1 and Fig. 2) for supplying makeup water to the heat supply system (STS) of the TPP or boiler house and line 10 (Fig. 1) for supplying part of the specified permeate for deeper desalination to the second stage of UOO-2 11 of the reverse osmosis unit. A decarbonizer D 12 and an electrodesionization unit UED 13 are connected in series to the UOO-2 output via permeate, from the output of which deeply demineralized water (diluate) is fed to the circuit with a steam boiler (PC).

According to the utility model UMO 5, the source water and the contaminated return condensate are made in the form of a single unit located between CSS 1 and UOO-1 6. Depending on the quality of the source water and the contaminated return condensate, UMO 5 in the form of a single unit for cleaning the mixture of these flows can be made as a pretreatment stage consisting of:

mechanical clarifying filters (bulk, self-cleaning mesh or disk);

clarifiers and mechanical filters (not shown);

clarifiers and / or ultrafiltration modules (not shown).

UOO-1 6 is equipped with a tank BK 14 for collecting the concentrate with a feed line 15 to the lower part of UMO 5 for loosening washing of the filter layer of the mechanical filter included in UMO 5.

The make-up water preparation system according to the utility model may preferably also include a temperature regulator RT 16 of the mixture of source water and contaminated return condensate with a temperature sensor DT 17 at the inlet of the specified water mixture in UOO-1 bis by two executive bodies, one of which is made in the form of a regulating valve RK 18 on the supply line 3 to the supply unit 1 of the source water, and the other in the form of a heater NIV 19 installed on the same line 3. The presence of RT 16 of the purified water mixture allows protecting the UOF membranes from the output outside the allowable process conditions of temperatures (typically 30 ° C), while for subcooling water, mainly in the winter heating to ensure its NIV 19 to the optimum temperature for 5 ULV 25-30 ° C.

UOO-2 11 is equipped with BC 20 with a line 21 of concentrate discharge to the inlet of UOO-1 6. UED 13 is equipped with BC 22 with a line 23 of concentrate discharge in BP 7.

An example of implementation 1

The combined preparation of makeup water vocational schools works as follows. At the CHPP with two units of vocational schools, the source water with a flow rate of 6.4 m ³ / h with a temperature of 10 ° C enters (Fig. 1) through RK 18 temperature regulator RT 16 in the unit 1. Here, with a flow rate of 2.8 m ³ / h at a temperature of 96 ° C, contaminated condensate from the CHP plant continuously flows.

The mixture of these flows will have a temperature of 35.8 ° C, which exceeds the temperature allowed for membrane elements of 30 ° C. As a result of this, according to the signal DT 17, the temperature controller RT 16 increases the flow rate of the source water through RK 18 to 9.4 m ³ / h. As a result, the mixture of source water and condensate will reduce its temperature to an acceptable value of 29.5 ° C. The total flow with a flow rate of 12.2 m ³ / h and a temperature of 29.5 ° C goes to ULV 5. Next, the mixture of source water and condensate is fed to UOO-1 6. UOO-2 11 concentrate is added to the entrance of UOO-1 6 with a flow rate of 0.8 m ³ / h. In total, UOO-1 6 receives for cleaning 13 m ³ / h of the water mixture. UOO-1 6 permeate with a flow rate of 9.5 m ³ / h is supplied to the BP 7 permeate tank, and UOO-1 6 permeate with a flow rate of 3.5 m ³ / h is discharged to the concentrate collection tank (BC) 14. The BP permeate tank 7 is also served concentrate UED 13 with a flow rate of 0.5 m ³ / h

From BP 7, permeate with a flow rate of 10 m ³ / h is fed to UOO-2 11 input. In this example, permeate from BP 7 is not fed to STS and to SG irrigation. The permeate UOO 2 11 with a flow rate of 9.2 m ³ / h is supplied to UED 13, and the concentrate with a flow rate of 0.8 m ³ / h is supplied to the input of UOO-1 6. The diluate UED 13 with a flow rate of 8.7 m ³ / h is sent to condensate storage tanks (not shown) for supply to a PC (not shown), and the concentrate with a flow rate of 0.5 m ³ / h is discharged to BC 22 UED.

Table 1 presents the change in the quality of the source water and contaminated condensate in the steps of the combined makeup water treatment system.

An example of implementation 2

At most TPPs, make-up water needs to be prepared not only for the steam-water paths of the circuits of energy recovery steam boilers, but also for the circuits of the heat supply system of the STS, and for TPPs with “dry” cooling towers - for the irrigation circuits of cooling towers.

The patented system provides the possibility of preparing make-up water for all three of the mentioned types of circuits. It should be noted that in such a system the total flow rate of makeup water and, accordingly, the flow rate of the source water will vary significantly depending on the season of the year. In this regard, an example of execution 2 is presented below for two operating modes (winter and summer) of a water treatment system at a thermal power plant with two vocational schools with a capacity of 235 mW each.

Conditionally summer mode

During the operating period at an outdoor temperature of t.v.≥ + 28 ° C, along with the supply of make-up water to the steam-water circuits of the PTU and to the circuits of the heat supply systems, the supply of demineralized water to the irrigation circuit of the "dry" cooling towers is necessary. In this mode, the source 1 receives the source water with a flow rate of 85 m ³ / h and a temperature of 17 ° C. At a flow rate of 6 m ³ / h with a temperature of 95 ° C, contaminated industrial condensate continuously flows here.

The mixture of these flows will have a temperature of 22 ° C, which is lower than the optimal value for the reagent treatment in the clarification unit, which is part of ULV 5. As a result of this, the supply of heating steam to NIV 19 increases the temperature of the mixture of source water and condensate by the signal of the temperature sensor DT 17 acceptable value of 25 ° C. The total flow with a flow rate of 91 m ³ / h and a temperature of 25 ° C enters the UMO 5 mechanical cleaning unit. If necessary, it is possible to increase the temperature of the mixture to higher values in the range up to 30 ° C.

Further clarified water at a rate of 91m ³ / h is fed to DOE-1 6. Of this amount, the permeate flow rate 69 m ³ / h is supplied to the tub 7 BP Permeate and concentrate flow 22 m ³ / h is discharged into a concentrate tank BK 14 . BED 22 also receives concentrate UED 13 with a flow rate of 2 m ³ / h.

The total consumption of permeate from BP 7 in the amount of 71 m ³ / h is distributed as follows:

- to recharge the circuits of the irrigation system of “dry” cooling towers of 35 m ³ / h;

- to replenish the circuits of the STS partially desalinated (softened) water 6 m ³ / h;

- at UOO-2 11 30 m ³ / h. From this flow rate, 27 m ³ / h through the decarbonization unit D 12 is supplied to the EDF 13, and 3 m ³ / h - concentrate UOO-2 11, is sent to the clarified water tank (not shown).

On UED 13 enters 27 m ³ / h. From this flow rate, a deeply desalted diluent of 25 m ³ / h is fed to the steam and water circuits of the CCGT unit and a concentrate of 2 m ³ / h is discharged to BP 7 UOO-1 6.

In this mode, there are 2 UOO-1 6 modules with a total capacity of 70 m ³ / h, 2 UOO-2 11 modules with a total capacity of 27 m ³ / h and 2 UED 13 modules with a total capacity of 25 m ³ / h.

Table 2 presents the change in water quality indicators for this example by the stages of its purification in the technological scheme.

Conditionally winter mode

During the operational period, at an outdoor temperature of t.v. <+ 28 ° C, makeup water is supplied to the steam-water circuits of the CCGT unit and the STS, but there is no need to supply demineralized water for irrigation of the SG. In this mode, the source 1 receives the source water with a flow rate of 37.5 m ³ / h and a temperature of 10 ° C. At a flow rate of 6 m ³ / h with a temperature of 95 ° C, contaminated return condensate is continuously supplied here.

The mixture of these streams will have a temperature of 21.7 ° C, which is below optimal for reagent treatment in a clarification plant. As a result of this, by the signal of DT 17, the supply of heating steam to NIV 19 increases until the temperature of the specified water mixture rises to a predetermined acceptable value of 25 ° C. The total flow with a flow rate of 43.5 m ³ / h and a temperature of 25 ° C is supplied to ULV 5. If necessary, it is possible to increase the temperature of the mixture to higher values in the range up to 30 ° C.

The clarified water with a flow rate of 43.5 m ³ / h is supplied to UOO-1 6. Of this amount, permeate with a flow rate of 34 m ³ / h enters BP 7, and the concentrate with a flow rate of 11 m ³ / h is discharged to BC 14. Part UED 13 concentrate with a flow rate of 2 m ³ / h enters BP 7.

Of the total flow rate of 36 m ³ / h of permeate:

- to replenish the circuits of the STS partially desalinated (softened) water 6 m ³ / h;

- at UOO-2 11 30 m ³ / h. From this flow rate, 27 m ³ / h through the decarbonization unit D 12 is supplied to the EDF 13, and 3 m ³ / h - concentrate UOO-2 11, is sent to the clarified water tank (not shown).

On UED 13 enters 27 m ³ / h. From this flow rate, a deeply desalted diluent of 25 m ³ / h is fed to feed the steam-water circuits of the vocational schools, and a concentrate of 2 m ³ / h is discharged to BP 7 UOO-1 6.

In this mode, 1 UOO-1 6 module with a capacity of 34 m ³ / h, 2 UOO-2 11 modules with a total capacity of 27 m ³ / h and 2 UED 13 modules with a total capacity of 25 m ³ / h are in operation.

Table 3 presents the change in water quality indicators for this example by the stages of its purification in the technological scheme.

As can be seen from tables 2 and 3, the quality of partially demineralized water after UOO-1 6 satisfies the requirements of PTE for make-up water of the heating system, the requirements for water for irrigation of cooling towers, and the quality of deeply demineralized water after UED-13 satisfies the requirements for the quality of make-up water of energy steam boilers -Utilizers of vocational schools.

Performance Example 3

In this example, we consider the mode of operation of the water treatment system of a large industrial boiler house of an oil refinery with steam boilers with a pressure of 1.3-4.0 MPa. The system includes SB, ULV (clarifiers and mechanical filters), UOO, BP (drawing 2). If the quality of demineralized water is not high enough in terms of hardness, the OOE permeate is additionally softened on sodium-cation exchange filters (not shown in the drawing).

The system operates as follows. Source water with a flow rate of 520 m ³ / h with a temperature of 13 ° C enters the mixing unit. Contaminated condensate flows continuously here with a flow rate of 100 m ³ / h with a temperature of 97 ° C.

The mixture of these streams will have a temperature of 26.5 ° C, which is below optimal for reagent treatment (liming with coagulation with ferrous sulfate) in a clarifier. As a result of this, according to the signal DT 17, the supply of heating steam to the source water 19 increases to increase the temperature of the mixture of source water and condensate to an acceptable value of 30 ° C. After the clarification installation, clarified water with a flow rate of 600 m ³ / h is supplied to UOO-1 6 (20 m ³ / h is the purge purifier). After UOO-1 6, permeate with a flow rate of 500 m ³ / h enters BP 7. A concentrate UOO-1 6 with a flow rate of 100 m ³ / h is discharged to BC 14 for the purpose of subsequent use for mechanical loosening washes of UMO 5 mechanical filters.

To deepen the softening of the permeate, it is additionally processed on sodium-cation exchange filters (not shown in Figure 2).

Table 4 presents the change in water quality indicators by the stages of its purification in the technological scheme.

Industrial applicability

The system for the preparation of make-up water according to the utility model meets the condition of "industrial applicability". The essence of the technical solution is disclosed in the formula, description and figures of the drawing is sufficiently clear for understanding and industrial implementation by relevant specialists on the basis of the current level of technology in the field of water treatment.

Claims (9)

1. The system for the preparation of make-up water for heat generating installations of a boiler house or power plant with combined generation of electric and thermal energy, containing: block installation of mechanical treatment of source water and contaminated return condensate; a mixing unit for the source water and the contaminated return condensate equipped with a mixing tank, and reverse osmosis installation, characterized in that: the specified block installation of mechanical cleaning of the source water and the contaminated return condensate is made in the form of a single unit located between the specified mixing unit and the reverse osmosis unit. 2. The make-up water preparation system according to claim 1, characterized in that said single unit comprises a bulk or self-cleaning mesh or disk mechanical clarification filter. 3. The system for the preparation of make-up water according to claim 1, characterized in that said single unit contains a clarifier and a mechanical filter. 4. The system for the preparation of make-up water according to claim 1, characterized in that said single unit contains a clarifier and an ultrafiltration module.

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