Feedback after 36 months of using the waste heat from a kiln for drying ceramics

Project Description

Decarbonation: 75 tons of CO2 saved, given an emission rate of 0.241 T of CO2/MWh consumed

Energy savings: 364 MWh saved per year, or 20%.

Productivity gain: Estimated by the customer at 5%.

Location : Meymac (19) – New Aquitaine – France

Client : Ceramics and development – Tegulys

Sector : Ceramics

Needs – customer requests :

The feasibility study conducted for the
Ceramics and Development – Tegulys
in Meymac, which aimed to study the recovery of high-temperature waste heat coming out of a cooking oven in order to use it in the plant’s dryer, was positive, both in terms of CO2 emissions and in terms of savings in natural gas consumption. The storage facility was therefore set up.

The study took into account a potential gain in productivity by studying in a second time the implementation of a pre-cooking chamber fed exclusively by the available waste heat. As a result, the firing cycle would be reduced and would make it possible to carry out more furnace cycles per year.

This part will be refined in a second study, the results presented take into account the current production and a complete recovery of the waste heat towards the dryer.

Project progress :

Analysis of the fatal heat source of the baking oven via a measurement campaign
Analysis of the energy needs of the dryer via the operation of its burner

Following this characterization, Eco-Tech Ceram sought the most relevant solutions to satisfy energy needs as much as possible. As this is out of phase with the heat source, a storage solution was chosen. Given the temperature levels (> 500°C), the Eco-Stock® solution was chosen.

Two solutions with or without taking into account the customer’s productivity gain were presented to the customer via a complete report.

Eco-Tech Ceram achievements :

Identification of cooking cycle periods where the fatal heat is greater than 500°C
Sizing of an Eco-Stock® solution : storage capacity of 1300 kWh
Aeraulic study on the smoke system network: sizing of the fans
Thermal study on the smoke system network: validation of calculations with insulator specialists
Study of the energy repercussions on the various stations of the factory following an increase in production
Plant-wide energy and environmental balance sheet
Economic study of the solution and financial arrangement
Design of the solution and implementation of the proposed solution
Site supervision, commissioning and performance monitoring

Description of the proposed solution:

The chosen solution is to use the waste heat contained in the fumes of the 8m3 furnace via the Eco-Stock® technology in order to compensate for the time lag between the deposit and the need. The need served here is the drying of clay products before the firing process, which no longer requires fossil energy to be realized. In addition, the dry heat produced by the Eco-Stock® allows a gain in productivity because it offers the possibility of drying products more quickly.