RU2627199C1 - Heat recovery unit - Google Patents

Abstract

FIELD: heating.

SUBSTANCE: unit includes a supply fan (7) and an exhaust fan (4), a polymer heat exchanger (3). The unit is vertically arranged and equipped with automatic washing system. The heat exchanger is made in the form of double-wall plates, the distance between which is provided by transverse ribs made along the entire length of the plates, forming air-tight channels in the space between the walls and ribs. The plates are installed parallel to each other with a gap equal to the thickness of the plate. The material of the heat exchanger is self-supporting cellular polycarbonate.

EFFECT: simplified heat exchanger structure.

2 cl, 3 dwg

Description

The invention relates to agriculture, namely to heat exchangers for providing a microclimate on livestock farms.

Known air heater for microclimate support systems on livestock farms (AS USSR No. 1307167, 1987), which is a polymer plate heat recovery heat exchanger. The disadvantages of the air heater is the lack of a flushing and recirculation system for indoor air.

Closest to the invention in terms of essential features is an electrothermal heat treatment plant designed to create and maintain the required microclimate parameters in the production facilities of livestock farms (RU 2296463 C1).

The electrothermal recovery installation includes a ventilating air fan, a heat exchanger made of polymeric materials, a supply air electric fan, a supply air electric heater, an air supply pipe, a supply air distributor, an exhaust air filter, a condensate drain, a supply air filter, a supply air duct, a recirculation duct with an air damper, exhaust air duct. The heat exchanger is presented in the form of a set of partitions made of polymer material parallel to each other with a gap, mounted on a supporting wooden frame, connected to the body and forming channels for the flows of heating and heated air, connected to the openings for supplying and discharging flows made in the housing.

The disadvantages of the prototype are the horizontal layout, suggesting the presence of additional air ducts, the presence of a supporting frame for the heat exchanger and the absence of an automatic washing system.

The claimed invention is aimed at solving the following problems: providing the required basic microclimate parameters of livestock buildings for various climatic zones while reducing energy consumption, simplifying the design and increasing its reliability.

To solve these problems, the device is mounted vertically and mounted directly in the roof of the production room, part of the housing acts outside the building as exhaust and supply air ducts. Cellular polycarbonate, a self-supporting material that ensures the tightness of the exhaust and supply channels, is used as heat transfer plates. Cellular polycarbonate plates are double-walled, the distance between the walls is provided by transverse ribs along the entire length of the plate, as a result, tight channels are formed in the space between the walls and the ribs. Positioning the plates in parallel with the gap relative to each other equal to the thickness of the plate, equivalent exhaust and supply channels are formed. Exhaust air moves vertically through the channels inside the plates, the supply air - in the space between the plates, which ensures the separation of flows. Warm, humid, polluted air is removed from livestock buildings, which contributes to the deposition of contaminants on the walls of the exhaust duct. In case of contamination of the heat exchange surface, the heat transfer resistance increases and the efficiency of heat recovery decreases. The use of filters in heat exchangers for livestock buildings does not justify itself, since filters with a high degree of purification have high resistance and require the use of high-pressure centrifugal fans, which are characterized by high energy consumption and high noise level. The plants are located directly in livestock buildings and their sound pressure level should not exceed 65 dB, which is typical for low-pressure axial fans. Low resistance filters do not provide a sufficient degree of air purification, and the heat transfer surfaces are still contaminated. To eliminate impurities, the device is equipped with a nozzle system, a time relay, an electromagnetic valve and connected to the water supply for periodic spraying of water in the exhaust channel, above the heat exchanger, which allows washing in automatic mode with a programmed frequency.

The proposed device is illustrated by drawings, which shows the functional diagram of the heat exchanger in the recovery mode with washing (Fig. 1), and in the recirculation mode (Fig. 2) as well as the diagram of the polymer heat exchanger (Fig. 3).

The heat recovery plant consists of an intake opening 1, a supply air duct 2, a polymer heat exchanger 3, an exhaust 4 fan, a tray 5 with a steam trap 6, a supply air 7 fan, an opening 8 with a recirculation flap 9, a pipeline with flushing nozzles 10 and an exhaust duct 11.

The heat recovery installation works as follows. A heat exchanger 3 (Fig. 1) with channels for supply and exhaust air is located in the housing. Supply and exhaust with mechanical motivation and carried out by supply 7 and exhaust 4 fans. Warm air removed from the room heats up the cold supply air, heat is exchanged through the plates separating the supply and exhaust channels - the walls of cellular polycarbonate 1 (Fig. 3), which corresponds to the principle of regenerative heat transfer. The gap between the plates and the separation of the supply channel is provided by sealing-remote gaskets 2 (Fig. 3). As a result of heat exchange, the exhaust air cools and can reach a dew point, which is accompanied by the precipitation of condensate, which, under the action of gravity, flows into the pan 5 (Fig. 1) and is removed through a steam trap 6. In the coldest period of the year at temperatures below -15 ° C, cooling is possible heat-exchange wall to negative temperatures, in such conditions, the condensate freezes, thickening the heat-exchange wall and reducing the cross-section, which reduces the efficiency of heat transfer. To resume operation, the installation switches to defrosting mode (Fig. 2), while the supply fan 7 turns off, cutting off the cold source, the damper 9 closes the exhaust duct and warm air passing through the heat exchanger 3, heats it and then goes back through the recirculation opening to the room . Completely thawed installation switches to recovery mode (Fig. 1).

The design includes a flushing system, which includes a pipeline with nozzles 10, a time relay and an electromagnetic valve. Thanks to the vertical layout, the area irrigated by the nozzles is minimized and equal to the area of the end face of the heat exchanger. The time relay opens the valve at a predetermined frequency, water is sprayed over the heat exchanger and irrigates the heat exchange surface, washing off the dirt into the sump. If necessary, it is possible to introduce a surfactant into the composition of the washing solution, its recirculation and regeneration.

Compared with the prototype, the proposed device can significantly simplify the design and increase its reliability, while ensuring the required basic microclimate parameters of livestock buildings for various climatic zones.

Claims (2)

1. Heat recovery unit, including supply and exhaust air fans, a heat exchanger made of polymer materials, characterized in that the installation is vertically arranged and equipped with an automatic flushing system, and the heat exchanger is made in the form of double-walled plates, the distance between which is provided by transverse ribs made along the entire length of the plates forming airtight channels in the space between the walls and ribs, while the plates are installed parallel to each other with a gap equal to the thickness not plates. 2. Heat recovery plant according to claim 1, characterized in that the heat exchanger is made of self-supporting honeycomb polycarbonate.

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