SU1767299A1 - Method of heat supply - Google Patents

Abstract

Use: in the field of heat supply. SUMMARY OF THE INVENTION: A method of heat supply by transferring heat to a closed circuit for a heating load and to an open circuit for a hot water supply. A portion of the heating load of the closed circuit is transferred to the open one, while the water flow in the closed circuit is maintained in accordance with the design load of the heating and ventilation in the system, the average water flow for the hot water supply, and the estimated temperature of the water supplied to the hot water supply. 1 il.

Description

The invention relates to the field of heat supply and can be used in heat supply systems of large settlements.

Analogues are known - methods of heat supply by transferring heat to the heating load and hot water supply to the open circuit of a two-pipe heat network 1, p. 32-33 and fig. 2.1 b on s. 30. For the implementation of the method, a combined heat and power plant is used as a heat supply source, in which the network water is heated in the main network preheaters and boilers 1, p. 274-275. In the return pipeline, the heat network supplies the substitute water, which is preliminarily softened in cationite filters, is decarbonated and deaerated 1, fig. 14.1 on p. 313.

The disadvantage of the described analog is the reduced reliability and quality of heat supply due to frequent damage to water boilers. Damage is caused by the deposition of corrosion products caused by the introduction of a significant amount of oxygen into the system with make-up water.

even while maintaining the quality standards of this water. A disadvantage of the analogue is also its reduced efficiency due to the need in most cases for an expensive high-capacity water treatment plant with sophisticated anti-scum treatment of make-up water.

There are also analogs - heat supply methods by transferring heat to the heating load and hot water supply to the closed loop of a two-pipe heat network 1, fig. 2.1 in on with. 30. In this method, raw tap water heated by mains water in water heaters is supplied to subscribers' water dispensers.

The disadvantage of this analogue is the reduced reliability and quality of heat supply due to corrosion damage to pipelines and heaters of local hot water systems running on untreated tap water. Damage to the preheaters, in turn, causes raw water to enter the heat network and damage.

WITH

WITH

hot water boilers due to scale and corrosion damage. The analogue also has a reduced cost due to the need to use local hot water heaters.

The heat supply method was adopted as a prototype by transferring heat to the closed circuit for heating load and to open circuit for hot water supply 1, fig. 2.1 e on s. thirty.

The disadvantages of the prototype are reduced reliability, quality and efficiency of heat supply due to the need to implement the expensive three- or four-pipe heat network, high energy costs for transporting network water, the flow of which is equal to the sum of the estimated water consumption for heating with ventilation and hot water supply, as well as due to the complexity of ensuring the water-chemical regime, ensuring the non-scaling operation of water boilers.

The aim of the invention is to increase the reliability, efficiency and quality of heat supply.

The goal is achieved by transferring a portion of the heating load of a closed circuit to an open one, while maintaining the flow rate of water in a closed circuit equal to

  QQ-AQ

Szzh

/

where C (t -tr) is part of the heating load of the closed circuit transmitted to the open;

Qo is the design load of the heating and ventilation in the system;

Grcp is the average water consumption for hot water supply;

C-heat capacity of water;

TI and TI are the calculated temperatures of the supply water in the flow and return lines according to the heating schedule;

tr is the design temperature of the water supplied to the hot water supply.

The drawing shows a fragment of a schematic diagram of the heat supply system in which the method is implemented.

The system contains supply and return 2 network pipelines of the closed circuit, which include the main network heaters 3 turbines 4 and the boiler 5, as well as the pipeline 6 of the open circuit, which includes capacitors 7 and 8 turbines 4 and 9, node 10 mind decantation or alkalinity reduction, decarbonizer 11, vacuum deaerator 12,

the main 13 and peak 14 network heaters. A chemical water treatment 16 is included in the make-up pipe 15 of the closed loop.

Consider a specific example of the implementation of the method in a system with a total design load of heating, ventilation and hot water supply (HWS) of 384 MW, incl. load of hot water of 64 MW, load of heating and ventilation Qo 320 MW. The initial water with a temperature of 5 ° C in the amount of 280.5 kg / s is heated in the built-in beams of condensers 7 and 8 to 35–40 ° C, reduced alkalinity or reduced by simplified technology using node 10, decarbonated and deaerated. Further, this water is heated in the design mode to g (150 ° C in heaters 13 and 14 and is supplied with an average water consumption for hot water supply, 8 kg / s through pipeline 6 consumers). For consumers, this water is supplied to heating devices, and return water after heaters with a temperature of tr 60 ° C are sent to water-dispensing appliances. Due to this, a part of the heating load C (rf-tr) is transferred to the open circuit.

i.e. 641 kg / s This

 QO-AQ

equal Oz.k.

C (ri-ta)

water is heated in a preheater x 3 and a hot water boiler 5 from a temperature of t g 70 ° C to t (150 ° C and supplied to closed circuit heaters. A part of open-circuit deaerated water with a flow rate of 2.7 kg / s is additionally softened and cooled give birth in chemical water treatment 16 and serves to feed the closed circuit.

Thus, the method of heat supply by transferring heat to the closed circuit to the heating load and to the open circuit to the hot water supply, characterized in that part of the heating load is transferred to the open one, while the water flow in the closed circuit

do-ad

support equal Sz.k. ,

C (n - T2)

allows to obtain a significant positive effect due to the following factors.

Covering the main part of the heating load with closed circuit network water, which feeds deeply softened and deoxygenated water, makes it possible to completely eliminate the formation of scale and corrosion deposits in boilers that are the most vulnerable elements of heat supply systems.

Transferring a portion of the heating load to an open circuit allows it to be covered in it using a peak mains heater, which has an insignificant temperature sweep compared to a hot-water boiler, which, in turn, makes it possible to use low-cost technology for preparing open circuit mains and significantly reduce the capital and operating costs of water treatment.

The method allows to significantly reduce the consumption of network water in comparison with the prototype and reduce the cost of its transportation, as well as the diameters of the network pipelines of the closed circuit.

Claims (1)

The invention is a method of heat supply by transferring heat to a closed circuit for heating load and to an open circuit for hot water supply, characterized in that, in order to increase reliability, efficiency and quality of heat supply by improving water chemistry. 0 five 0 mode, excluding the introduction of boilers by scale and corrosion deposits, part of the heating load of the closed circuit is transferred to the open one, while the water flow in the closed loop is maintained equal to QQ -DO Sz-mustache (p-g2y where AQo is the design load of heating and ventilation in the system, kW; .C (ri -tr). - part of the heating load of the closed circuit transmitted to the open; Grcp is the average water consumption for hot water supply; C is the heat capacity of water; R | and G2 - design temperature of the network water in the flow and return lines x according to the heating schedule. tr is the design temperature of the water supplied to the hot water supply. 12 S /