SU139418A1 - Method of connection to external water heating systems of heating and hot water supply systems - Google Patents

Description

There are known methods for heat supply of subscribers with combined heat supply for heating and hot water supply through a two-pipe heat network. The disadvantage of these methods is that they do not provide the hot water supply of buildings only with the return water of the heating system.

Proposed, according to the invention, the method is devoid of this disadvantage. The essence of the invention is to use a special schedule of network water temperatures and install on the inlets sequentially flow heat exchangers with temperature controllers at + 60 ° with open and at + 70 ° with closed hot water supply.

The principle of operation of the proposed subscriber heat supply method with a combined heat supply for heating and hot water supply through a two-pipe heat network is based on a change in the usual temperature schedule for the qualitative regulation of heat supply.

FIG. 1 is a temperature control chart with a closed hot water circuit. The t, tl and 4 lines show the water temperatures in the supply and return lines according to the usual schedule of quality control.

In the new graph required for operation of the proposed scheme, the return water temperature is assumed to be constant and equal to + 70 °, i.e. t / is taken instead of / 3.

To supply the required heat for heating with the same amount of water as in a regular schedule, save the same temperature difference between the supply and return water in the new schedule as in the normal one, we obtain temperature lines in the supply lines of the new schedule.

The adjustment of the water temperature of the subscribers to the water temperature of the usual schedule is carried out by installing a flow heat exchanger according to the scheme of FIG. 2

No 139418-2B In this scheme, the water supplied from the heat network with the temperature of the direct water of the new schedule t or t in the countercurrent heat exchanger is cooled to the temperature of the direct water of the usual schedule t or t and enters the heating system.

The return water from the heating is partially or completely directed to the secondary circuit of the same heat exchanger and is cooled to the temperature by cooling the water in the primary circuit.

To maintain the return water temperature at + 70 °, an automatic regulator RPD-70 is installed on the jumper of the secondary circuit of the heat exchanger, which directs that amount of water from the heating system through the heat exchanger, which is necessary to obtain a mixture temperature of + 70 °.

Providing a fresh water temperature at the heat source according to a new graph of FIG. 1 and maintaining the return water temperature by the automatic controller RPD-70, we always get the water temperature of the primary circuit behind the heat exchanger / 2 or t, corresponding to the direct water of the usual schedule, since ti-4, and are equal to each other according to the conditions of construction graphics.

Thus, for hot water heaters, as a heating medium, we obtain return water with a constant temperature of + 70 °.

For open hot water supply, the temperature of the return water is maintained by the heat exchanger and the RPD-60 controller not lower than + 60 °, therefore the temperature lines of the new schedule ti and tl of FIG. 3 coincide with the temperature lines of the normal graph to the level of + 60 ° in the return line from the heating, and then change according to the same principle as for the graph with the closed hot water supply circuit shown in FIG. I. In this scheme it is possible to have a hot water supply always always from the return line with a temperature not lower than + 60 °.

The installation of successive flow heat exchangers at the inputs of subscribers is made according to the scheme of FIG. four.

According to the proposed method, new graphs (Figs. 1 and 3) have been developed for high-quality regulation. A new graph can also be constructed for stepwise regulation, which, according to the proposed method, will combine all the positive properties of both the scheme and the regulation.

The insignificant cost of heat exchangers at the inlets is economically justified by a number of the above benefits given by the proposed method, especially since the material for the heat exchangers is completely black steel, since in both contours the water is deaerated.

The feasibility of introducing the proposed method is fundamentally possible and due to the fact that in existing and projected municipal heat supply systems and residential buildings a significant place is occupied not only by CHP plants, but also by district boiler houses and even boiler houses for a group of buildings with cast iron water boilers, which exclude the possibility of cheap centralized hot water supply according to well-known schemes.

Subject invention

The method of heat supply of subscribers with combined supply of heat for heating hot water supply through a two-pipe heat network, characterized in that, in order to provide hot water