Sustainability 2020

April 7, 2020

An online conference focusing on sustainability in the cement industry

Turboden

Save the heat – boost your cement process waste gas

Turboden is a global leader in the design, manufacture, and maintenance of Organic Rankine Cycle (ORC) systems, with more than 40 years of experience. Founded in 1980 in Italy, it is now part of MHI group, a leading Japanese company that is well-known worldwide.

ORC systems are based on Rankine Cycle technology, capable of generating electric and thermal power by exploiting several types of sources among which waste heat recovery (WHR) is one of the most important.

Today, there are currently about 400 Turboden ORC plants in total, out of which 34 are used in WHR plants.

The ORC goal, when applied at WHR application, is to increase energy efficiency and to generate profit by valorising a waste heat source, reducing the specific production cost by decreasing the energy demand and therefore improving industrial companies’ sustainability.

Among the industrial sector, cement plants represent one of the most attractive processes where heat recovery can be applied successfully.

The efficiency of the cement production process has been improving in the last decades, nevertheless still today, 30 – 35% of the energy input in cement production is lost in the off-gas.

Waste heat in cement plants, in the form of exhaust gas, is available at two points: the pre-heater tower (PH) and the clinker cooler (CC).

The heat contained in exhaust gases is typically transferred indirectly using an intermediate loop (thermal oil or pressurised water circuit) to the ORC plant which produces electric power.

The amount of electric power counts for 10 – 30% of the cement plant electricity consumption, meaning that the monthly electricity bill is reduced by the same percentage.

Besides heat recovery, there are several improvements on cement process efficiency. These improvements lead to a decrease in exhaust gas temperature, so that in the future, it is expected to be able to deal with a lower temperature of exhaust gas.

This trend benefits ORC technology since it can exploit low temperature with a good electrical efficiency.

Turboden ORC clients recognise several advantages for ORC based heat recovery systems. Firstly, the system can operate in a fully automatic mode without risk and there is no requirement of supervision personnel, thus reducing operational cost. In addition, the ORC has flexible operation in a wide range of thermal power loads. In fact, it can be operated very quickly and automatically at partial loads, following the cement plant production programme without interrupting electricity production and thus increasing power plant reliability. Leading on from this, an important feature is the high efficiency even at partial load. The ORC needs minimum maintenance requirements. In particular, no partial condensation occurs at the level of the turbine. The blades are not exposed to wear or corrosion due to the properties of the working fluid, and this is a key factor in long-term O&M costs. The long life without the necessary major overhaul completes the good maintenance features. Finally, the possible configuration with no water consumption and consequently no need of water treatment means the ORC is a winning technology in countries where there is a shortage of water.

Turboden references confirm that ORC technology is a proven technology in cement WHR, helping to increase the sustainability of cement production thanks to its ability to recover heat even at low temperatures and with good efficiency. Considering the trend of a greener industry, a broader vision that takes into account the environmental benefits of reducing energy wasted and global CO2 emissions and the benefits of decreasing electrical energy consumption is surely a winning decision.

 

Speaker

Sabrina Santarossa

Sabrina Santarossa
Sales Application Manager - Industrial Heat Recovery, Turboden

Sabrina Santarossa is Sales Manager for industrial heat recovery at Turboden with focus on projects in the cement, glass and steel production processes.

Sabrina Santarossa supports potential customers to find the optimised solution for each project.

 

Andrea Barbon

Andrea Barbon
Sales and Proposal Engineer - Industrial Heat Recovery, Turboden

Andrea Barbon is Sales and Proposal Engineer for industrial heat recovery at Turboden with a focus on projects in the cement, glass and steel production processes.

Andrea Barbon supports potential customers in the selection and purchase of ORC for each project.