Removal of VOCs Generated by an Industrial Painting Machine
In an industrial painting process, the use of efficient paint filters is essential for removing dust, overspray, paint residue, and contaminants from the extracted air. For this application, Coral designed a complete system consisting of bag-type paint filters, an industrial extraction system, and a high-efficiency afterburner for VOC abatement.
The system was designed to extract the polluted exhaust air from a painting machine, separate the solid particles present in the airflow, and then treat the volatile organic compounds through thermal oxidation.
Key Plant Data
- System Type: VOC Extraction and Filtration for Paint Spraying
- Air flow rate: 700 Nm³/h
- Filter system: CLEAN model pocket prefilter
- VOC Treatment: CTR Afterburner
- Fan: PRVM 400/2 – 2.2 kW
- Available fuel: natural gas from the utility grid
- VOC concentration: 5,000 mg/Nm³
- Inlet air temperature: 20–30 °C
Painting filters for separating dust and debris
The first stage of the system consists of a bag filter, which belongs to the category of paint filters used to capture dust, particles, and residues resulting from the painting process. This stage is essential for protecting the subsequent sections of the system and ensuring more effective treatment of the contaminated air.
The overspray filters installed upstream of the afterburner reduce the particulate load in the intake stream by capturing any solid residues before the air is sent to the thermal solvent abatement stage. In the second filtration stage, the contaminated air is collected at the outlet of the painting machine and conveyed to the filtration system. A high-efficiency fan generates the vacuum necessary to draw in the airflow and maintain a constant flow rate throughout the system’s operation.
After passing through the pocket-type paint filters, the air is directed to the afterburner, where volatile organic compounds are treated. The treated air is then discharged outdoors through a stainless steel exhaust stack.
Afterburner Operation for the Removal of VOCs from Paint Spraying
The centerpiece of the entire system—custom-built to meet the end customer’s specific needs— is undoubtedly the CTR afterburner, designed to oxidize the volatile organic compounds present in the intake air. In this specific case, the system treats a flow rate of 700 Nm³/h of air contaminated with solvents, with an inlet temperature of approximately 30 °C. After passing through the paint filters installed upstream of the system, the air is conveyed to the thermal treatment section.
The combustion chamber is thermally insulated with insulating bricks and ceramic fiber panels to reach and maintain the temperatures required for the oxidation of pollutants. The design parameters specify a combustion temperature of 750 °C and a residence time of one second, thereby facilitating the complete removal of VOCs from the gas stream.
Inside the plant, the airflow is divided into two parts: one portion enters the afterburner directly, while the remainder is directed through the burner. The system utilizes a principle of exhaust heat recovery, preheating the incoming air from approximately 30 °C to 350 °C. The preheating is carried out via a counterflow heat exchanger, in which the air to be treated recovers part of the heat contained in the flue gases exiting the afterburner. This configuration helps make the thermal treatment process more efficient. The modulating gas burner is equipped with a flame detector, an ignition system, a servo-controlled regulator for modulating the ratio of natural gas to combustion air, a combustion air fan, and safety pressure switches.
Management of the paint fume extraction system with filters
To ensure effective control and proper operation throughout the filtration process, the machine is equipped with a control panel installed on the unit itself. This panel allows users to monitor key operating parameters, displaying temperature indicators, combustion chamber temperature control, the maximum temperature alarm, and automatic burner control with its associated safety mechanisms.
This configuration allows for monitoring the system's operating conditions and ensures continuous treatment of the contaminated air generated by the painting process.
Comprehensive Solution for Filtration and Air Treatment in Paint Booths
This plant layout demonstrates how an integrated system of paint filters, industrial ventilation, and post-combustion can meet air treatment requirements in the presence of solvents and VOCs.
The combination of a bag filter and an afterburner makes it possible to treat both the particulate fraction—consisting of dust and paint residues—and the gaseous component, which consists of volatile organic compounds. The result is a custom-designed system for capturing, filtering, and abating the pollutants generated by an industrial painting machine.
Coral and manufactures solutions for air extraction, filtration, and treatment in industrial painting processes. Our technicians can analyze the characteristics of the process, the air flow rate, the concentration of pollutants, and the type of contaminant to be treated, identifying the most suitable configuration of paint filters, extraction systems, and VOC abatement systems.
