GB2614249A

GB2614249A - Thermal Storage to maintain the maximum temperature

Info

Publication number: GB2614249A
Application number: GB2118728.1A
Authority: GB
Inventors: Cooper Rustin
Original assignee: Coopertec Systems Ltd
Current assignee: Coopertec Systems Ltd
Priority date: 2021-12-24
Filing date: 2021-12-24
Publication date: 2023-07-05

Abstract

A thermal storage vessel 1 for storing hot or cold storage fluids includes a first manifold 2 having a circular configuration which receives fluid from an energy source 7, such as a heat pump or chiller, and supplies fluid to a process 9, such as a heating or cooling apparatus. A second circular manifold 4 may be provided below the first manifold for use with a lower temperature fluid. A third circular manifold 3 may be located between the first and second manifolds and used with an intermediate temperature fluid. The circular manifolds may have open peripheral pipe connections to either supply fluid into the thermal store, or take fluid from the thermal store. The storage vessel may also include a fluid separation plate 5 with a one-way orifice, such as floating ball valve. The plate may be domed or conical and separate a cooler section of the fluid from a warmer section of the fluid to ensure minimal mixing. The circular motion of the fluid flowing through the manifold facilitates an uninterrupted additional flow through the thermal store, which can be added to or subtracted from the flow demanded by the process.

Description

DESCRIPTION

Thermal Storage to Main o the Optimum Temperatures of Stored Fluids for Longer Periods Circular manifolds incorporated within a thermal store, will improve the thermal storage holding capacity, facilitating simultaneous operation with the heating or cooling equipment and maintain the target temperatures for the discharge cycle. In addition, an arrangement for separating the cooler section from the warmer section in a thermal store, with a one-way flow, will reduce the effects of stratification.

Preamble To encourage the drive for industry to decarbonise their energy processes, heat pumps are typically used to raise Low temperatures (low grade energy) to high temperatures (high grade energy). The resultant high temperature energy can be stored in a heating medium (eg water, oil or other fluids), in large insulated tanks, open void tanks being the most common. In fact any hot fluid from any heat source can be stored in a thermal store.

Industrial processes could use this hot fluid to replace steam for example, but they will need the heating medium to be at a constant high temperature.

Hot medium stored in a large, open void, insulated tank will not maintain the maximum temperature for long. During the process of using the hot medium, the convection, turbulence, and mixing, quickly reduces the maximum temperature and could, in extreme cases, render all the stored heat energy unusable. Open void tanks are also limited in the amount of thermal energy stored because of temperature stratification.

A typical source of low grade (low temperature) energy is from refrigeration systems where the thermal energy from the cold side is transferred to a warm side (typically 35 °C) as part of the refrigeration cycle. However the warm side temperature (typically 35°C) generally is too cool to be usable in most cases. The storage of warm fluid (low grade energy) from refrigeration systems within a thermal store is another application. The advantage being the elimination of the need for simultaneous cooling and heating.

Another use for thermal storage is for cold fluids in cooling applications where chilling equipment is more economical to run during off peak hours and/or peak demand outstrips the cooling capacity of the chiller. The chilled fluid can also be thermally stored for use on demand.

Statement of Invention

A fluid storage vessel with circular manifolds and a domed or conical plate for the separation of the cooler section from the warmer section along with a one-way orifice to ensure minimal mixing. Circular manifolds for the cooler fluid, hot fluid and intermediate temperature fluid are strategically placed at optimum levels within the vessel to take account of the temperature stratification within the vessel.

These circular manifolds have open peripheral pipe connections to either supply fluid into the thermal store or take fluid from the thermal store as the process demands, minimising internal turbulence. The circular motion of the fluid within the manifold as it flows through, facilitates an uninterrupted additional flow through the thermal store, which can be added to or subtracted from the flow demanded by the process.

As a hot thermal store, these circular manifolds allow for combining stored thermal energy with the thermal energy provided by the heating source (eg heat pump), maximising the output.

As a cold thermal store, these circular manifolds allow for combining stored thermal energy with the thermal energy provided by the cooling source, maximising the available cold fluid for the process. Drawing attached to this proposal, shows a cut-away sketch of the thermal storage tank for a heating process.

For applications for storing cold fluids or low grade warm fluids, the circular manifolds serve the same purpose but are in a different position.

Drawing 1 shows a cut-away of the thermal storage tank. The tank can be sealed and pressurised.

Drawing Key: 1. Outer Shell 2. Upper Circular Manifold: this is a 'hot fluid' circular manifold allowing both in-line heat source (heat pump) operation and thermal draw down.

3. Mid Circular Manifold: this is the 'intermediate temperature' circular manifold to reduce mixing of warm fluid with the hot fluid.

4. Lower Circular Manifold: this is the 'lower cooler fluid return' circular manifold allowing both in-line heat source (heat pump) operation and thermal store return.

5. Separate Plate: a cooler fluid separation plate with one-way floating ball valve 6. Fluid Return: a cooler fluid return with swing valve to divert if the return is at intermediate temperature.

7. Swing Valve Supply: a supply from the heating source (heat pump) with swing valve to divert intermediate temperature fluid so as not to degrade the hot water stratification.

S. Supply Heating Source: Supply to the heating source.

9. Hot Fluid Supply to the process.

Claims

CLAIMS1. The thermal storage tank for storing hot heating medium maintains the maximum temperatures for longer than a conventional open void tank.
2. The thermal storage tank for storing cold medium for a cooling process.
3. A thermal storage tank according to claims 1 and 2, with circular fluid outlet manifold to enable stored energy to be used in conjunction with a heating or cooling source such as a heat pump or chiller.
4. A thermal storage tank according to claims 1 and 2, with a circular manifold to enable the cooler fluid medium to return to the tank and/or return to the heat source such as heat pump or chiller.
5. A thermal storage tank according to claims 1 and 2, with a circular intermediate temperature manifold to enable fluid not at the target high temperature to be introduced into the thermal store without compromising the hot fluid stratification. The intermediate manifold could also be available to supply warm fluid to a process not requiring the hot fluid.
6. A thermal storage tank according to claims 1 and 2, with cooler fluid separation and one-way orifice to minimise mixing enabling more energy stored compared with similar sized Open void tanks.