RU2775330C1 - Installation for utilization of high-temperature steam condensate and generation of secondary energy resources (ser) - Google Patents

Abstract

FIELD: heat recovery systems.

SUBSTANCE: invention relates to systems for the recovery of heat from secondary energy resources and can be used in thermal power engineering, as well as in various industries for using the heat of industrial condensate. The task to be solved by the claimed technical solution is the development of a highly efficient installation for the utilization of heat from secondary energy resources (high-temperature steam condensate) with enhanced functionality. Installation for utilization of high-temperature steam condensate and generation of secondary energy resources (SER) contains a line for supplying high-temperature steam condensate; network water line; condensate drain line; heat exchangers; air coolers (AC); tank for collecting steam condensate; pumps that circulate network water and pump out steam condensate; pressure meter; temperature sensor. The line for supplying high-temperature steam condensate is divided into a line for generating heat from the SER and a line for chilling on air coolers. The network water line after the heat exchangers is divided into a line for technological needs and a line for the needs of consumers for heating. A steam condensate flow controller is installed on the supply line of high-temperature steam condensate for heat generation of SER, in front of two sequentially located heat exchangers of stages I and II. An automated heating station was installed on the network water line for the needs of consumers for heating.

EFFECT: increasing the productivity of the installation, reducing operating costs, as well as using the heating and technological schedule of the heating network with a constant temperature in the supply pipeline, which allows the use of the coolant not only for heating and hot water supply (HWS), but also for technological needs.

6 cl, 3 dwg

Description

The invention relates to systems for the recovery of heat from secondary energy resources and can be used in thermal power engineering, as well as in various industries for using the heat of industrial condensate.

TERMS AND DEFINITIONS.

Network water: Specially prepared water that is used in the water heating system as a heat carrier (Rules for the technical operation of thermal power plants. Terms and definitions PTE TE, approved by the Ministry of Energy of March 24, 2003 N 115, hereinafter - PTE TE).

High-temperature steam condensate - condensate with a temperature up to 150°C after the activation of saturated steam at process units.

There are various methods for recycling secondary energy resources, where recycling is carried out by transferring heat from a source of secondary energy resources to a traditional coolant, which is water.

Thermal power stations are known, containing supply and return pipelines of network water, a steam turbine with heating steam extractions and a condenser, to which pressure and discharge pipelines of circulating water are connected, network heaters connected by a heated medium between the supply and return pipelines of network water and connected via a heating medium to heating extractions, a heat pump unit, the evaporator of which is connected via a heating medium to a drain pipeline of circulating water (USSR author's certificate No. 1590569 for the invention "Thermal Power Plant", IPC F01K 17/02, publ. 09/07/1990). The disadvantage of the known device is the low efficiency due to the limitation of the network water temperature after the network heaters, due to the amount of steam in the heating extractions, and the inefficient use of the heat of the exhaust steam condensate in the station cycle.

A well-known steam condensate disposal system of a steam turbine contains at least two heaters installed in series on the network water pipeline, each of which is made with steam supply from the turbine and condensate removal, an expander placed between the heaters with the removal of steam and condensate, the inlet of which is connected to the outlet condensate of the second heater installed along the network water flow, and the condensate outlet - to the condensate outlet of the first heater, and the heat exchanger installed on the network water pipeline in front of the first heater along the network water flow and connected through the heating medium with its inlet and outlet, respectively, to the vapor outlet and condensate outlet the first heater (USSR author's certificate No. 1816872 for the invention "The system of cascade draining of the condensate of the heating steam of the heaters of the cogeneration steam turbine with staged heating of network water", IPC F01D 21/00, publ. 23.05.1993). The disadvantage of the known system is that when the steam heat is recovered in the installed heat exchanger, the return network water temperature rises.

A well-known industrial condensate heat recovery system includes a steam condensate supply line, a heat exchanger, a condensate cooler, a network water line, a condensate drain line to a condensate collection tank and a pump. (V.M. Borovkov, A.A. Kalyutik, V.V. Sergeev "Heat engineering equipment" Textbook, Moscow, Publishing Center "Academy", 2011, p.128). The disadvantage of the known system is the limited use of hot water coming from heating networks as a heating medium for industrial heat exchangers, since during the heating season with natural regulation of heat release, its temperature is not constant and varies from 70 to 150°C. (V.M. Borovkov, A.A. Kalyutik, V.V. Sergeev "Heat engineering equipment" Textbook, Moscow, Publishing Center "Academy", 2011, p. 9-10).

Known closest to the set of essential features to the claimed technical solution, the system of heat recovery of industrial condensate, including: supply line of high-temperature steam condensate; line of low-temperature steam condensate, line of network water; condensate drain line; heat exchangers; air coolers (AVO); tank for collecting steam condensate; pumps that circulate network water and pump out steam condensate; pressure meter; temperature sensor, actuators providing redirection of high-temperature steam condensate flow for summer mode and for winter mode (RF patent No. 137576 for utility model "Industrial condensate heat recovery system", IPC F01K 7/34, publ. 20.02.2014). The disadvantage of the known system is the difficulty of adjusting the supply of thermal energy in lines with different temperature flows and maintaining the temperature schedule of the heat network established by the PTE TE (p. 2.5.6; p. 6.2.59). Obtaining an additional amount of heat during utilization requires the modernization of the heating network receiving this heat (replacing network pumps with pumps of higher productivity, increasing the diameters of pipelines). In addition, the specified installation operates in two modes - winter and summer, and, as a result, requires switching equipment and adjusting the hydraulic and temperature regimes of the heating network.

The task to be solved by the claimed technical solution is the development of a highly efficient installation for the utilization of heat from secondary energy resources (high-temperature steam condensate) with enhanced functionality.

The technical result achieved as a result of solving the problem is to increase the productivity of the installation, reduce operating costs, as well as use the heating-technological schedule of the heating network with a constant temperature in the supply pipeline, which allows the use of the coolant not only for heating and hot water supply (DHW ), but also for technological needs.

The specified technical result is achieved by the fact that the installation for the utilization of high-temperature steam condensate and the generation of secondary energy resources (SER)) contains a supply line for high-temperature steam condensate; network water line; condensate drain line; heat exchangers; air coolers (AVO); tank for collecting steam condensate; pumps that circulate network water and pump out steam condensate; pressure meter; temperature sensor. The line for supplying high-temperature steam condensate is divided into a line for generating heat from the VER and a line for chilling on air coolers (ACUs). The network water line after the heat exchangers is divided into a line for technological needs and a line for the needs of consumers for heating. A steam condensate flow controller is installed on the supply line of high-temperature steam condensate for heat generation of VER, in front of two sequentially located heat exchangers of stages I and II. An automated heating station was installed on the network water line for the needs of consumers for heating.

It is preferable that the temperature sensor be installed in the network water line, after the heat exchangers and functionally connected to the steam condensate flow controller.

It is preferable that the steam condensate flow regulator installed on the high-temperature steam condensate supply line ensures the steam condensate flow to the heat exchanger and maintains the temperature of the network water at the outlet of the stage II heat exchanger no more than 115°C.

It is preferable that the automated heating point provides a decrease in the temperature of the network water supplied to the needs of consumers for heating to a level not exceeding 95°C.

It is preferable that air coolers (ACUs) contain frequency converters for the speed of the fan impeller, which ensure a constant temperature of the condensate entering the collection tank.

It is preferable that the plant contains a booster pump to compensate for the loss of network water pressure in the heat exchanger and maintain the calculated pressure in the network water line, functionally connected to a pressure sensor installed on the network water line before the network pump.

Comparative analysis of the claimed invention with the prototype showed that in all cases of execution it differs from the known, closest technical solution:

implementation of a line for supplying high-temperature steam condensate, divided into a line for generating heat from a VER and a line for chilling on air coolers (AVO);

implementation of the network water line after the heat exchangers, divided into a line for technological needs and a line for the needs of consumers for heating;

the presence on the supply line of high-temperature steam condensate for generating heat from the VER of two successively located heat exchangers of the 1st and 2nd stages;

the presence of a steam condensate flow regulator,

the implementation of the steam condensate flow controller installed in front of two successively located heat exchangers;

the presence of an automated heating point;

the implementation of an automated heat point installed on the network water line for the needs of consumers for heating.

A comparative analysis of the claimed invention with the prototype showed that in the preferred embodiment it differs from the known, closest technical solution:

the implementation of the temperature sensor installed on the network water line, after the heat exchanger;

the implementation of the temperature sensor, functionally associated with the flow controller of the steam condensate;

the presence of a coolant flow regulator that ensures the flow of steam condensate to the heat exchanger and maintains the temperature of the network water at the outlet of the second stage heat exchanger no more than 115°C;

the presence of an automated heat point that provides a decrease in the temperature of network water supplied to the needs of consumers for heating, to a level not exceeding 95 ° C.

the implementation of air coolers (AVO) containing frequency converters of revolutions of the fan impeller;

the presence of a booster pump to compensate for the pressure loss of network water in the heat exchanger and maintain the calculated pressure in the network water line;

the implementation of a booster pump, functionally associated with a pressure sensor installed on the network water line, in front of the network pump.

The presence on the line of a high-temperature steam condensate flow for the generation of thermal energy of heat exchangers of stages I and II, connected in series, provides a two-stage heating of network water, allowing it to be heated to a higher temperature, due to a larger volume of steam condensate cooling. Separation of the supply line for high-temperature steam condensate into the line for heat generation of the VER and the line for chilling on air coolers (AVO), separation of the supply water line after the heat exchangers into a line for process needs and a line for the needs of consumers for heating, the presence of a steam condensate flow controller, installed on the supply line of high-temperature steam condensate to generate heat from VER, in front of two sequentially located heat exchangers of stages I and II, as well as the presence of an automated heat point installed on the network water line for the needs of consumers for heating, increases the productivity of the installation, ensuring the generation of additional heat and allows use the heat carrier both for heating and hot water supply (DHW), and for technological needs without reconfiguring the equipment, while maintaining the temperature schedule of the heating network with a constant temperature in the supply pipeline. The presence of a flow controller installed on the line of high-temperature steam condensate flow for heat generation limits the flow of high-temperature steam condensate for heat generation on heat exchangers and ensures that network water is maintained at a constant temperature of not more than 115 ° C at the outlet of the heat exchanger, which allows the use of a heat carrier not only for heating and hot water supply, but also for technological needs according to the heating and technological schedule. At the same time, the remaining steam condensate is sent for cooling down in air coolers.

The temperature controller installed on the network water line after the heat exchangers maintains a constant temperature of the network water through the executive flow controller, which, in turn, regulates the flow of steam condensate to the heat exchangers. Frequency converters of speed of the impeller of the fan on air coolers (ACUs) ensure the maintenance of the calculated temperature of the cooled steam condensate in the steam condensate discharge line to the condensate collection tank. The pressure sensor on the network water line in front of the network pump sends an impulse to the network water booster pump and provides the booster pump operation mode to compensate for network water pressure losses in the additional heat exchanger and maintain the calculated pressure in the heating network supply pipeline. The presence of automated heat points ensures a decrease in the elevated temperature of the network water supplied after the heat exchangers for the needs of consumers for heating to a temperature not exceeding 95 ° C, in accordance with the heating temperature schedule for the operation of the heat network and the temperature of the heat carrier for internal heat supply systems in service buildings, established by clause 6.1.6 of the Code of Rules SP 60.13330.2012 "HEATING, VENTILATION AND AIR CONDITIONING" SNiP 41-01-2003, approved. Etc. Ministry of Regional Development of Russia dated June 30, 2012 N 279, hereinafter - SP 60.13330.2012.

All this provides an increase in the productivity of the high-temperature steam condensate utilization plant and a decrease in its operating costs by obtaining an additional amount of heat for the needs of the enterprise, both for heating and for technological needs, by regulating the supply of thermal energy with an increased temperature schedule without changing the elements of the heating network (network pumps and pipeline diameters) in the mode of automatic maintenance of the temperature of the cooled steam condensate and the temperature of the network water supplied to consumers, without additional adjustment of the hydraulic and temperature conditions of the heating network.

The present invention is illustrated in the schematic drawing shown in Fig. 1 and the graphs shown in Fig. 2, 3.

In FIG. 1 shows a schematic drawing of a plant for the utilization of high-temperature steam condensate and the generation of secondary energy resources.

In FIG. 2 shows the heating temperature schedule for the operation of heat networks, compiled in accordance with the PTE TE (clause 2.5.6; clause 6.2.59), as well as in compliance with the requirements of SP 60.13330.2012 (clause 6.1.6).

In FIG. 3 shows the heating and technological temperature schedule for the operation of the heating network based on the proposed installation.

The installation for the utilization of high-temperature steam condensate and the generation of secondary energy resources (SER)) contains a line 1 for supplying high-temperature steam condensate, a line 2 for network water; condensate drain line 3; heat exchangers 4, 5; air coolers (AVO) 6; container 7 for collecting steam condensate; pump 8, which circulates network water, and pump 9, which pumps out steam condensate; network water pressure sensor 10 in front of pump 9; network water temperature sensor 11 after heat exchanger 5. Line 1 for supplying high-temperature steam condensate is divided into line 12 for generating heat from VER and line 13 for cooling down on air coolers (AVO) 6. Line 2 of network water after heat exchangers 4, 5 is divided into line 14 for technological needs and to line 15 for the needs of consumers for heating. On the line 12 for supplying high-temperature steam condensate for generating heat from the VER, in front of two successively installed heat exchangers 4 (stage I) and 5 (stage II), a steam condensate flow controller 16 is installed. On line 15 of network water for the needs of consumers for heating, an automated heating point 17 is installed. temperature not more than 115°С. Automated heat point 17 provides temperature control of the network water supplied to the needs of consumers for heating in line 15, in accordance with the heating temperature schedule for the operation of the heat network and the temperature of the heat carrier for internal heat supply systems in service buildings is not more than 95 ° C. Air coolers (AVO) 6 contain frequency converters of 18 revolutions of the fan impeller, providing a constant temperature of the steam condensate entering the tank 7. pump 19.

In FIG. 2 shows the heating temperature schedule for the operation of heat networks, compiled in accordance with the PTE and TE (clause 2.5.6; clause 6.2.59), as well as in compliance with the requirements of SP 60.13330.2012 (clause 6.1.6). Line T1 denotes the graph of the temperature regime of network water supplied to consumers for heating, and line T2 denotes the graph of the temperature regime of return network water supplied from consumers after heating.

In FIG. 3 shows the heating-technological temperature schedule for the operation of heat networks based on the proposed installation for the utilization of high-temperature steam condensate and the generation of secondary energy resources. Line T1 denotes a graph of the temperature regime of the network water at the outlet after the heat exchangers 4, 5, and line T2 denotes a graph of the temperature regime of the return network water coming from heat consumption facilities.

Installation of heat recovery of high-temperature steam condensate and generation of secondary energy resources (SER) operates as follows.

Part of the high-temperature steam condensate coming from a heat source (not shown in the drawing) through line 1 is sent through line 12 and transfers heat through heat exchangers 4, 5 to network water passing through line 2. Part of the high-temperature steam condensate from line 1 is not used for generation thermal energy in the non-heating period, after the exclusion of the heating heat load, and is sent via line 13 to the air coolers of the air cooler 6. The estimated temperature of the steam condensate after the air cooler at the level of 80 ° C is maintained by the frequency converter 18 revolutions of the fan impeller. The cooled steam condensate is sent to the steam condensate collection tank 7 and, further, by the pump 9 for pumping out the steam condensate along line 3, it is directed to the heat source. The pressure sensor 10 installed on line 2 of the network water to the circulating network pump 8 ensures the operation of the booster pump 19 to compensate for the pressure loss of the network water in the heat exchangers 4, 5 and maintain the calculated pressure in the supply pipeline of the heating network (line 2). Line 2 of network water takes the heat of steam condensate in heat exchangers 4 and 5, heats up to a temperature of no more than 115 ° C (exceeding the temperature of the heating schedule for service and household heat consumption facilities (95 ° C), approved by the set of rules SP 60.13330.2012 (Fig. 2 )). The increased temperature on the line 2 of the network water after the heat exchangers 4, 5 is maintained by the temperature sensor 11 through the actuator of the coolant flow regulator 16 according to the heating-technological schedule of the heat network shown in Fig. 3. Network water according to the heating and technological schedule is sent to heat consumption facilities, where it is used for technological needs, and during the heating period for the needs of domestic consumers, after lowering the temperature of the network water in automated heating points 17 to the heating schedule.

The use of the proposed installation provides an expansion of the functionality of the system for the utilization of industrial condensate heat and allows the utilization of secondary energy resources, depending on the thermal loads of the enterprise, not only for heating and hot water supply, but also for technological needs in the mode of automatically maintaining the parameters of steam condensate and network water.

Claims (6)

1. Installation for the utilization of high-temperature steam condensate and the generation of secondary energy resources (SER), containing a line for supplying high-temperature steam condensate; network water line; condensate drain line; heat exchangers; air coolers (AVO); tank for collecting steam condensate; pumps that circulate network water and pump out steam condensate; pressure meter; a temperature sensor, characterized in that the high-temperature steam condensate supply line is divided into a line for generating heat from a VER and a line for chilling on air coolers (AVO); the network water line after the heat exchangers is divided into a line for technological needs and a line for the needs of consumers for heating; the plant additionally comprises: a steam condensate flow controller installed on the supply line of high-temperature steam condensate for generating heat from the VER in front of two sequentially located heat exchangers of stages I and II, and an automated heating point installed on the network water line for the needs of consumers for heating. 2. Installation according to claim 1, characterized in that the temperature sensor is installed on the network water line after the heat exchanger and is functionally connected to the steam condensate flow controller. 3. The installation according to claim 1, characterized in that it contains a flow controller on the line of high-temperature steam condensate, which ensures the flow of steam condensate to the heat exchanger and maintains network water at the outlet of the heat exchanger with a constant temperature of not more than 115 ° C. 4. Installation according to claim. 1, characterized in that it contains an automated heat point that reduces the temperature of the network water supplied to the needs of consumers for heating, to a level not exceeding 95 ° C. 5. Installation according to claim. 1, characterized in that the air coolers (AVO) contain frequency converters of the fan impeller speed, ensuring a constant temperature of the condensate entering the collection tank. 6. The installation according to claim 1, characterized in that it contains a booster pump to compensate for the loss of network water pressure in the heat exchanger and maintain the calculated pressure in the network water line, functionally connected to a pressure sensor installed on the network water line in front of the network pump.

Images