Aeinnova

LIFE - HEAT-R

Welcome

Celsa: Conclusions

The waste heat recovery technology has been tested by these five different prototypes with different variations in power electronics, thermal collector contact surfaces, cooling system and the thermoelectric generators to configure the best option for each type of heat source.

Efficiency is one of the main parameters analysed in each project. This parameter shows how much energy is extracted from waste heat.

The efficiency of the prototype depends on the heat source, the heat collector type and the cooling system applied.

CELSA group produces 2.4 million tons of steel per year. Production is separated into corrugated and smooth round rods, rolled wire, flats rods, squares, angles rods, and structural sections.

The energy recovery system (Heat R-System) installed in the industrial plant that CELSA has in Castellbisbal (Barcelona) makes use of the waste heat generated by radiation in the beam blank cooling area.

The operating cycle of the beam blank production is 24 hours a day, 7 days a week, and the temperature of the heat source is about 600 ºC although the temperature in the metal heat collection plate is about 240 ºC.

The recovery system obtains heat by conduction through the contact between the heat collector of the WHRU and the metal heat collection plate that receives the radiation from the beam blanks. Therefore, the recovery system is non-intrusive.

WHRU modules uses water heat-exchanger (water-block) for their cooling to obtain the maximum temperature difference between the two sides of the Peltier cells. Water is pumped from an internal cooling water line. The water-cooling temperature is about 25 ºC.

In this project, the energy recovery system is based on this type of WHRU:

 

WHRU – WBCD100

 

 

 

  • Cooling system principle: Forced water convention
  • Cooling components Cold plate or water heat exchanger (waterblock).
  • Heat capture system principle Forced air convection – gas exhaust.
  • Thermal collector Plane thermal collector
  • Electrical energy generator Thermoelectric generator TEG – Peltier cell
  • Peltier cell number 36 cells 40 *40 mm

 

The main feature of this device is that it groups a set of 36 thermoelectric generators into a single unit. This design was created to group as many thermoelectric generators as possible in the smallest possible space, optimising the ratio of power generated per unit area.

 

Results

 

Thermal collector plate temperature 200 – 248 ºC
Generation area WHRU 1705,7 cm2
Mean power generated *32 W
Maximum power generated *40 W
Energy generated *280,32 kWh/year
Power density. *47,62 W/m2
Heat dissipated by the heat source 685 W
Heat flow through Heat R-System by conduction *1126 W
Efficiency *3,55 %

 

To generate more energy, it is necessary to capture the maximum amount of heat flow. This is possible if the system is intrusive and there is contact between the fins of the heat collector and the hot gases. This is not the case in this project.

 

In CELSA, the system is non-intrusive and the heat is obtained by surface contact between the heat collector and the metal heat collection plate, which receives the heat by radiation and therefore, increases its temperature. However, when the WHRU is in contact with the metal heat collection plate the surface temperature of the heat collector is reduced and, consequently, the efficiency is reduced.

 

On the other hand, there is a higher heat transfer due to the higher number of mounted Peltier cells.

 

The action of the forced water cooling system allows a significant temperature differential between the two sides of the Peltier cells, which results in higher electrical power generation, but the efficiency is not as high as if the system were intrusive.

 

From the standpoint of the installation, the water-cooling system requires a hydraulic loop with a pump. It is essential to ensure a continuous supply of cooling water to avoid damaging the prototype by exceeding the maximum working temperatures of the components. Therefore, installing two pumps instead of one or automating the start-up of the pump when the process starts are options to ensure the water supply. It is also crucial to ensure that all valves are open in the hydraulic circuit.

 

On the other hand, the quality of the water supply is important. The water must be free of suspended solids to avoid possible clogging that could hinder or prevent the water supply and thus damage the equipment.

 

Ciments Molins: Conclusions

The waste heat recovery technology has been tested by these five different prototypes with different variations in power electronics, thermal collector contact surfaces, cooling system and the thermoelectric generators to configure the best option for each type of heat source.

Efficiency is one of the main parameters analysed in each project. This parameter shows how much energy is extracted from waste heat.

The efficiency of the prototype depends on the heat source, the heat collector type and the cooling system applied.

The activity of Ciments Molins Group focuses on manufacturing, distributing and selling cement, concrete, mortars, aggregates and concrete prefabricates, and running activities and production plants in different countries.

The energy recovery system (Heat R-System) installed in the industrial plant that Ciments Molins has in St. Vicenç dels Horts (Barcelona) makes use of the waste heat generated in the walls of the rotatory kiln used for firing the clinker and which are close to the burner.

The operating cycle of the rotatory kiln is 24 hours a day, 7 days a week, and the heat source temperature is about 200 ºC although the temperature inside the rotatory kiln is up to 1000ºC. The device must withstand ambient temperatures up to 40 ºC.

The recovery system obtains heat by conduction and is non-intrusive.

The forced air generated by fans cools the equipment to obtain the maximum temperature difference between the two sides of the Peltier cells.

In this project, the energy recovery system is based on a new type of WHRU:

 

WHRU – HSCD100

 

 

  • Cooling system principle: Forced air convention
  • Cooling components Heat sink with four fans.
  • Heat capture system principle Conduction
  • Thermal collector Plane thermal collector.
  • Electrical energy generator Thermoelectric generator TEG – Peltier cell
  • Peltier cell number 36 cells 40 *40 mm

 

The main feature of this device is that it groups a set of 36 thermoelectric generators into a single unit. This design was created to group as many thermoelectric generators as possible in the smallest possible space, optimising the ratio of power generated per unit area.

 

Results

 

Heat source temperature 191 – 213 ºC
Generation area WHRU 1705.7 cm2
Mean power generated 5.43 W
Maximum power generated 6.86 W
Energy generated 47.6 kWh/year
Power density 31.83 W/m2
Heat dissipated by the square heat source 310 W
Heat flow through Heat R-System by conduction 491 W
Efficiency 1.40 %

 

Prototypes based on a forced air-cooling system with a heat collector in contact with a hot surface have been found to be the least effective and efficient.

To generate more energy, it is necessary to capture the maximum amount of heat flow. This is possible if the system is intrusive and there is contact between the fins of the heat collector and the hot gases. At Ciments Molins, the system is non-intrusive and the heat is obtained by surface contact between the heat collector and the hot wall of the rotary kiln.

On the other hand, there is a higher heat transfer due to the higher number of Peltier cells mounted.

Unlike the forced water-cooling system, the forced air-cooling system cannot absorb all the heat. This means that there is no temperature difference between the sides of the Peltier cells and the efficiency is lower.

Celsa Steel Industry: Pilot Installation

The installation was carried out on December 17, 2021.

The installation of the pilot required electrical and plumbing works that were carried out prior to the installation of the pilot by the maintenance staff of Celsa, following the instructions of the mechanical and the electronic department of AEInnova.

The final installation of the recovery system was carried out by Celsa’s staff following the instructions of AEInnova’s staff.

Below you can see some of the photographs taken at the installation.

 

 

Ciments Molins: Pilot Installation

The installation was carried out on May 31, 2021 and on September 28, 2021.

The final installation of the recovery system was performed jointly with the staff of AEInnova and Ciments Molins.

Below you can see some of the photographs taken at the installation.

 

Distiller Chemical Industry: Pilot Installation

The installation was carried out on December 24, 2020.

The installation of the pilot required mechanical works that were performed by a specialized company following the instructions of the mechanical department of AEInnova.

The final installation of the recovery system was performed jointly with the staff of AEInnova and Distiller.

Below you can see some of the photographs taken at the installation.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Celsa Steel Industry: Prototype Implementation

All components of the heat recovery system are integrated and connected to generate the maximum amount of power from the waste heat source.

In CELSA, a metal support is required to fix the plate that captures heat by radiation as well as the heat recovery unit (WHRU).

 

Figure . Support and metal plate

ADIPEC OIL&GAS 2021

AEInnova has exhibited at the ADIPEC Exhibition and Conference global Oil&Gas from the 15th to the 18th of November. We have presented in the technical session Oil & gas 4.0 the paper that deeps into the digital transformation of a leachate biogas plant of Ferrovial in Catalonia, Spain. 

There has been high interest from other speakers of Saudi Aramco Total Refining and Petrochemical Company (SATORP))Eni and Schlumberger, and the attendees of oil and engineering companies. 

 We have big potential to grow in this market worldwide thanks to our batteryless IoT solution to monitor vibrations and temperature without batteries.

Cleantech Business Booster

The Business Booster is EIR UbbiEberfy’s annual two-day international networking event that showcases 150+ sustainable energy technologies under one roof. Each year the event rotates among European capital cities, which have included Barcelona, Berlin, Amsterdam, Copenhagen, and Paris. This event was a great chance to detect new opportunities and business models for your company.
We have had the opportunity to make 6 new contacts.

COP 26

AEInnova – Alternative Energy Innovations, one of the first UE Scale-ups to be invested by the European Innovation Council and SMEs Executive Agency (EISMEA) EIC Fund has the proud to announce that we have been invited to speak in the UNFCCC UN COP26 – UN Climate Change Conference in @glasgow next November.

 This is the third time that the United Nations invites AEinnova to explain our vision of the industry 4.0 climate impact and how our technology can transform these industries into more sustainable and digital. #cop24 in Katowice (Poland) and Cop25 (Chile-Madrid) were exciting experiences!

 In this conference, we have introduced the concept: “The usage of renewable and alternative energies to power a new IoT generation devices”.

EIC GHC Co-Creation with CEPI

AEInnova – Alternative Energy Innovations participated in the first European Innovation Council and SMEs Executive Agency (EISMEA) #EUeic GHG program with Cepi (The European association representing the paper industry) and 19 Top EU Startups, all of them fully committed to the environment. Our autonomous batteryless long-range IoT solution powered by waste heat was presented to Mondi GroupEssityStora EnsoKoninklijke VNP among others. The first EU paper & pulp company testing this solution has been Gomà-Camps Group, located in Catalonia, Spain, fully committed with environment and digitalization. Other use cases for predictive maintenance were introduced in our presentation (Ferrovial ServiciosSACYREnel Group…). 

 In this small celebration, we were able to make 6 contacts of 26 attendees. 

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