Poppi Clementino SpA: Systems for reducing SOx and NOx pollutants integrated with energy recovery plants

Founded in 1986, Poppi Clementino SpA has expanded its product range over the years to cover a variety of industrial sectors and now specialises in the fields of energy saving and filtration.

Founded in Reggio Emilia in 1986, Poppi Clementino SpA has expanded its product range over the years to cover a variety of industrial sectors and now specialises in the fields of energy saving and filtration.

Experience gained in the field has led the company to focus recently on dry environmental purification systems, which are generally more versatile and efficient and allow for more effective maintenance.

In recent years, a number of industrial sectors have begun devoting much greater attention to the emissions of certain pollutants following the introduction of more stringent environmental regulations.

This applies in particular to the levels of sulphur and nitrogen oxides SOx and NOx in production fumes generated by the transformation and combustion of raw materials, which are now subject to increasingly stringent checks to ensure compliance with the lower emission limits.

In this context, Poppi SpA has developed integrated systems for reducing these pollutants that combine purification treatments with energy saving devices. The reduction in SOx and NOx emissions is achieved by injecting reagents and catalysts into the fume circuit and adopting specific operational measures: guaranteeing adequate distances between the elements in question and installing a bag filter downstream of the circuit. Another important aspect is control of the fume temperatures, which must be monitored constantly to allow the required filtration to be performed.

The high temperatures involved mean that there is plenty of room for energy recovery applications through the installation of latest-generation heat exchangers (P-Rex© Series) in the plant. These machines are efficient, self-cleaning and easy to maintain and are capable of producing a significant quantity of heat that can be reused in the production process.

One of the biggest benefits of the process is the fully automatic management of the devices by means of an electrical panel supervision system, which is capable of controlling all the machinery using sensors, pressure switches and thermocouples with the aid of dedicated software. To further improve flexibility, for several years Poppi SpA plants have been equipped with integrated tele-assistance systems for remote operation worldwide.

The figure shows an indicative flow diagram for an SOx and NOx reduction and energy recovery plant, where the heat exchanger allows for the production of a significant quantity of heat that can be reused directly in the operating cycle. The system is highly flexible and can be adapted to any real-world configuration. 

Example of a practical case of a plant installed in a glass factory capable of producing a significant quantity of heat by means of a heat exchanger.

• Fume flowrate: 13,000 Nm3/h
• Fume temperature: 480°C 
• SOx entering filter: 750 mg/Nm3
• NOx entering filter: 1000 mg/Nm3
• SOx after filtration system: < 200 mg/Nm3
• NOx after filtration system: < 300 mg/Nm3
• Particulate after filtration system: < 10 mg/Nm3
• Thermal power generated by heat exchanger: 950,000 kcal/h (1,100 kW)​