Slaughterhouse odour control with wet scrubber and biofilter
Case history on the design and installation of a system for reducing odours, VOCs, ammonia and H₂S
Project Overview
In this case history we present an odour control system designed and installed by Tecnosida® for a company operating in the pork processing industry. Wastewater generated during production is treated through equalisation and denitrification tanks, which release odours, Volatile Organic Compounds (VOCs), ammonia, hydrogen sulphide and other aromatic compounds.
To minimise these emissions and reduce their environmental impact, the customer entrusted Tecnosida® with the design and installation of a multistage system for treating the gaseous stream.
| Project data | Value |
|---|---|
| Flow rate | 12.000 m3/h |
| Operating temperature | Max 40 °C |
| Pollutants to be treated | Odours and various types of VOCs |
| Inlet pollutant concentration | ~ 18.000 ouE/m3 |
| Target value | 500 ouE/m3 |
Engineering assessment and design of the slaughterhouse odour control system
Our specialised technicians carried out an on-site inspection to assess the current conditions and identify the most suitable solution based on the production process, the nature of the emitted pollutants and the characteristics of the airflow in terms of temperature and humidity.
Given the high concentration of odorous compounds extracted from the two equalisation tanks and the denitrification tank, we conducted an analysis of odor dispersion and fallout. Based on the results obtained, we designed a multi-stage treatment system consisting of a wet scrubber and a biofilter specifically engineered to remove both VOCs and odours generated during slaughterhouse operations.
Ammonia and H₂S (hydrogen sulphide) abatement system
The system was custom-designed by selecting the most suitable technologies to reduce the different types of pollutants present in the exhaust stream.
We paid particular attention to ammonia and hydrogen sulphide concentrations, as excessive levels can inhibit or even damage the microorganisms responsible for biological degradation inside the biofilter.
To ensure long-term biological efficiency, we maintained inlet concentrations below 50 mg/Nm³ for ammonia and 25 mg/Nm³ for hydrogen sulphide.
Wet scrubber for industrial odour control
The flow extracted from the tanks is conveyed to the wet scrubber, where the first stage of air purification takes place.
The scrubber separates liquid and solid particles present in the gas stream, reducing the pollutant load entering the biofilter.
In addition to its pretreatment function, the scrubber also adjusts the humidity of the process air, creating optimum conditions for the development and survival of the bacterial population within the biofilter.
Biofilter for slaughterhouse odour treatment
The biofilter, installed downstream of the wet scrubber, consists of a reinforced concrete structure filled with an organic filter medium that provides the ideal environment for microorganisms responsible for the biological degradation of odorous compounds.
To ensure consistent long-term performance, the biofilter requires continuous moisture control and scheduled maintenance. For this reason, several engineering features were incorporated into its design to simplify maintenance operations and preserve treatment efficiency over time.
Biofilter maintenance
To guarantee continuous plant operation during maintenance activities, the biofilter was divided into three independent sections.
An integrated network of pipes and valves distributes the airflow evenly and allows the specific section requiring maintenance to be isolated without shutting down the entire system.
This configuration makes it possible to replace the organic filter media quickly and efficiently while avoiding production downtime.
Biofilter moisture and monitoring instrumentation
Proper biofilter performance is ensured by an irrigation system that maintains a constant moisture level in the filter bed. To accurately monitor this parameter, four moisture sensors were installed: one at the inlet and one in each of the three biofilter sections.
This arrangement enables continuous tracking of operating conditions and allows prompt corrective action whenever required.
Results achieved and compliance with BAT-AEL requirements
Laboratory testing confirmed that the system designed and installed by Tecnosida® achieved a 96% reduction in odour emissions, successfully reaching the target concentration of 500 ouE/m³.
The installation fully complies with BAT-AEL values (Best Available Techniques Associated Emission Levels) for emissions released into the atmosphere.
More specifically, the system meets the applicable emission limits for odours, organic compounds, ammonia (NH₃) and hydrogen sulphide (H₂S) generated by slaughterhouses and related food processing facilities.
Remote monitoring and control of the slaughterhouse odour control system
The entire odour control system is managed through a dedicated PLC with remote control capabilities.
Operators can monitor all key process parameters and detect any operating anomalies in real time.
The main monitored variables include the scrubber water level, along with the temperature and humidity in each biofilter section.
Automation and remote supervision ensure reliable plant operation, reducing the risk of unplanned downtime and optimising resource consumption.
Do you need to treat similar emissions?
If your production process generates VOCs, odours, ammonia or hydrogen sulphide, rely on Tecnosida®‘s expertise.
Contact us today to arrange a site survey: we will design and build a custom air pollution control system tailored to your process requirements.