JPH0821698A - Exhaust heat recovering apparatus with circulating circuit - Google Patents

Abstract

PURPOSE:To provide a small-sized low-cost exhaust heat recovering apparatus in which a circulating circuit is combined with a heat exchanger pump in order to recover exhaust heat from exhaust liquid. CONSTITUTION:Circulating circuits 3, 4, 5, 6 and 11, 4, 12, 14 are provided at an exhaust heat side and a heat receiving side via a heat exchanger 4. Two liquids are passed several times to the exchanger 4. The liquids reaching predetermined temperatures are exhausted from the circuits. The exhausted liquid quantity is automatically supplied in the same quantity to the circuit.

Description

Detailed Description of the Invention

[0101]

[Industrial application] Hot springs, baths,
Pools, aquaculture plant heating tanks, power plants, various industrial effluents, etc.
It can be used as a heat exchange device between two liquids.

[0092]

2. Description of the Related Art Generally, a heat exchanger is large in size by a method of obtaining a predetermined temperature in both the exhaust heat side and the heat receiving side. Further, in the case of the circulation type, a water storage tank is required.

[0093]

It is desired to recover the heat source of the waste liquid as much as possible. Therefore, we want to control the temperature of the exhaust heat side and the heat receiving side appropriately. We would like to make it compact with no heat storage tank and unitized heat exchanger, pump, and piping.

[004]

The entire layout of this apparatus is shown in the attached drawing (FIG. 1). The heat exhaust side and the heat receiving side are arranged around the heat exchanger.

First, on the exhaust heat side, high temperature waste liquid enters from the inlet, (1) inlet side thermometer, (2) check valve, (3) pump,
(4) Return to (5) bypass, (6) check valve, (3) pump via heat exchanger. The drainage circuit repeats the circulation circuits (3), (4), (5) and (6) to circulate a large amount of drainage liquid at high speed. Only the amount of liquid that has dropped to a predetermined temperature out of the circulating amount is discharged through (7) the flow rate control valve and (8) the outlet thermometer.

Next, in the same circuit on the heat receiving side, the supply liquid enters from the inlet, (9) inlet side thermometer, (10) check valve, (1)
1) pump, (4) heat exchanger, (12) bypass,
(13) Return to check valve, (11) pump. The circulating fluid (11), (4), (12) and (13) is repeated in the supply liquid, and a large amount of liquid is circulated at high speed. Control valve, (1
5) Discharge through the outlet thermometer.

For example, 100 liters per minute for 1 pass at 10 ° C.
When increasing (decreasing) or increasing (decreasing) 200 liters by 10 ° C. in 2 passes per minute, the heat exchanger is 60,00.
Although 0 kcal / H is required, the latter (two-pass method) requires a smaller heat transfer area of the heat exchanger and the heat exchanger becomes smaller.

The same amount of liquid discharged is automatically supplied to this circuit.

The discharge temperature of both circuits is controlled by the flow rate control valve (7).
Perform in (14). The amount of heat exchange in both circuits can be confirmed by comparing the inlet side and outlet side thermometers (1) and (8) on the exhaust heat side. The same applies to the heat receiving side.

[0101]

[Application] When it is desired to automate the outlet temperature of both circuits, it is sufficient to use the procedure for installing the proportional electric temperature control valve described in the reference number 940401 for which a patent has been applied.

The heat exchanger used here is applicable to all types such as plate type, shell and tube type, spiral type, double tube type, shell and coil type and the like.

It is desirable that the exhaust liquid on the exhaust heat side recovers thermal energy as much as possible, that is, is discarded at a low temperature. Therefore, this can be achieved by connecting this type in a two-stage, three-stage, or multi-stage system.

The heat exchange medium can be used not only in the above-mentioned "liquid" vs. "liquid" combination, but also in "liquid" vs. "gas" or "gas" vs. "gas".

When the heat source on the exhaust heat side is as abundant as the hot spring water, a circuit may be installed only on the heat receiving side. In this case, the heat receiving side temperature can be brought close to the drainage side temperature. Generally, the heat exchanger and pump capacity are determined by the energy held on the exhaust heat side and the heat receiving side.

[Brief description of drawings]

[Fig. 1] Piping system diagram

[Explanation of symbols]

 (1) Inlet thermometer (11) Pump (2) Check valve (12) Bypass (3) Pump (13) Check valve (4) Heat exchanger (14) Flow control valve (5) Bypass (15) Outlet side thermometer (6) Check valve (7) Flow control valve (8) Outlet side thermometer (9) Inlet side thermometer (10) Check valve

Claims (1)

[Claims] 1. In order to recover the heat of the waste liquid, the liquid is repeatedly circulated in heat exchange, lowered to a predetermined temperature, and discharged from this circuit. Further, this circuit is also arranged on the heat receiving side in the same manner, and the two liquids are respectively circulated in the heat exchanger to complete mutual heat exchange, and then discharged from this circuit. The discharged liquid amount is automatically supplied to this circuit. Since the conventional one-way type heat exchange system is provided with the inlet circuit and the bypass circuit in the outlet circuit and has the circulation type without the water tank, the heat exchanger can be downsized.