Odor nuisance is usually a symptom, not an isolated malfunction
In a composting or aerobic stabilization system for biodegradable waste, odors do not arise in isolation from the technology itself. Their intensity is influenced by, among other factors, the quality and preparation of the feedstock, aerobic conditions, moisture content, temperature, retention time of the material, the method of aeration, and the effectiveness of post-process air extraction and treatment.
If the material is too compacted, unevenly moistened, or if air does not flow through its entire volume, oxygen-deficient zones can easily form. The process becomes unstable, takes longer, and the risk of odor nuisance increases. A similar effect can result from insufficient air intake from the process space, a spent or improperly maintained biofilter bed, inadequate fan capacity, or control systems that are not adapted to the system’s current load.
Important: Effective modernization does not begin with the selection of a single piece of equipment. First, you must determine where the actual bottleneck in the process lies and whether the problem is technological, operational, infrastructural, procedural, or a combination of several factors.
When does a composting facility indicate that the current setup is no longer sufficient?
An increase in the volume of selectively collected biowaste and variations in its composition can significantly alter the operating conditions of a facility that was designed for a different waste stream and a different load. Before a serious operational problem arises, there are usually a series of warning signs:
- the duration of the intensive process or the material's curing time is extended;
- The number of operator interventions and manual parameter adjustments is increasing;
- uneven temperatures or problems with oxygenation of the batch occur;
- the biofilter and ventilation system are operating at full capacity;
- some of the batch requires the process to be repeated or a longer holding time;
- The number of complaints about odors is increasing, especially during adverse weather conditions;
- The actual capacity of the system begins to deviate from the plant's needs or the design specifications.
Each of these signals may have a different source. Therefore, simply increasing the fan speed, adding an odor neutralizer, or changing the operating schedule will not always solve the problem. Sometimes, such measures merely shift the bottleneck to another part of the system.
Why can't "odor neutralization" replace monitoring of the biological process?
Odor-masking or odor-neutralizing agents may serve as a temporary solution in certain areas, but they do not eliminate the root cause of the unstable process. If there are anaerobic zones in the material, airflow is uneven, and post-process air is not effectively extracted and treated, the problem will recur.
In a modern facility, it is essential to control the entire process chain: from feedstock preparation, through the intensive biological phase, to gas collection and deodorization. Only this approach allows us to simultaneously reduce the risk of odor nuisance, stabilize process conditions, and improve the utilization of available process volume.
Sealing, Ventilation, and Pressure Control—How Does the NOVA-KOMP Approach Work?
AK NOVA’s NOVA-KOMP technology was developed for the composting and aerobic stabilization of biodegradable waste. It is based on injecting air into the bioreactor and extracting post-process air; depending on the system configuration and the process phase, the system can operate in either positive-pressure or negative-pressure mode. Proper pressure control directs the flow of air through the material and limits its uncontrolled escape to the outside, while the selection of the operating mode depends on the chosen technological variant and the current process parameters.
The process air is then directed to a treatment system, the core component of which is a biofilter with a biological bed. Depending on requirements, the deodorization system can be expanded to include additional stages, such as water scrubbers. The scope of material irrigation, automation, and the method of fan control—manual or automatic—depends on the selected installation configuration and process parameters.
A key feature of NOVA-KOMP is its proprietary aeration system using channels covered with concrete grates. The design was developed to provide a large active surface area, mechanical strength, and the ability to periodically clean the channels. In practice, the process layout is always designed for a specific waste stream, existing infrastructure, and site conditions.
Process control instead of reacting after the fact
In a biological system, the parameters of the material change over time. Therefore, it is important not only to aerate the material but also to measure and interpret what is happening inside the pile or bioreactor. AK NOVA’s solutions provide for monitoring the dynamics of the process using, among other things, temperature and oxygen probes, as well as moisture content assessment. Based on the results, fan operating parameters can be adjusted and, if necessary, the material can be irrigated. The scope of measurement and automation depends on the specific system configuration chosen.
This model reduces reliance on intuitive operator adjustments. Instead of reacting only when the material fails to meet the required parameters or an odor problem arises, the operator can make adjustments to the process earlier.
The Two Stages of the Process and Effective Time Management
The NOVA-KOMP system is designed for a two-stage composting or aerobic stabilization process. The intensive phase in the bioreactors is typically designed to last approximately 2–4 weeks, after which the material enters the maturation phase in the open-air composting area, which continues for several more weeks. The specific durations depend on the properties of the feedstock, the objective of the process, and its actual course.
This is important from a productivity standpoint. If the intensive phase is unstable, every additional week that the bioreactor is occupied reduces the number of possible cycles per year. Improving oxygen conditions and process predictability can therefore not only reduce the risk of odor nuisance but also lead to better utilization of the existing infrastructure.
Step-by-Step Modernization of a Composting Facility
A well-planned modernization should be treated as an engineering project, not a series of ad hoc purchases. At AK NOVA, the starting point can be a technological audit of the existing installation, along with recommendations for modernization. In practice, it is advisable to organize the process into the following stages:
- Audit of the current status and operational data. The analysis covers, among other things, the volume and characteristics of the waste stream, cycle times, material temperature and oxygenation, the condition of ventilation systems, leachate discharge, air purification efficiency, the method of feeding the material, and the actual throughput of individual sections. Site conditions and land availability are also important.
- Identifying the source of the problem. The goal is not to compile a list of all possible improvements, but to identify the elements that are actually limiting the process. Sometimes it will be aeration, sometimes biofiltration, feedstock preparation, automation, bioreactor geometry, or several elements at once.
- Technical and Technological Concept. At this stage, modernization options are compared, their impact on capacity, operation, and costs is assessed, and the feasibility of utilizing existing facilities is evaluated. AK NOVA prepares technical and technological concepts and functional-utility programs for waste management facilities, which allows for the integration of technological requirements with subsequent design and construction.
- Formal and legal review. The scope of the modernization should also be assessed in terms of the required decisions and permits. Not every technological change involves the same set of procedures. Depending on the nature of the project, environmental assessments, updates to documentation, administrative decisions, or sector-specific permits may be required. Therefore, the formal process must be determined on a case-by-case basis before work begins.
- Design, construction, and phasing of work. Once a design option has been selected, design documentation and an implementation schedule are prepared. At a facility that must continuously accept waste, it is particularly important to phase the work in such a way as to minimize downtime and maintain operational continuity to the greatest extent possible. AK NOVA has its own design, engineering, and construction capabilities, enabling it to manage a project from concept through completion.
- Commissioning, optimization, and crew training. Modernization is not complete until the new system is operating under actual conditions. Commissioning allows for the verification of ventilation, irrigation, and automation settings, while operator training facilitates the maintenance of these parameters once the system is handed over for normal operation.
Does modernization mean building a completely new facility?
Not always. In many facilities, the greatest potential lies in the existing space, which is not being used optimally due to outdated ventilation, control systems, or insufficient air purification. Sometimes, modernization may involve replacing selected systems and automation, while in other cases it will require the reconstruction of bioreactors, the expansion of a biofilter, or additional process space.
That is precisely why it is worth comparing options before making an investment decision. Building new facilities makes sense when required by the target capacity or the lack of technological reserve. However, if the main problem is an unstable process, adding more space without addressing the root cause may increase the cost of the investment without solving the operational problem.
Composting Facility Modernization and the Risk of Complaints and Inspections
Odor complaints are not just a matter of public image. For the facility operator, they also mean the need to analyze the source of emissions, document how the process is conducted, and demonstrate that the facility is operated in accordance with the applicable permits and environmental requirements. In the event of technical problems, a response based on data and a corrective action plan is much safer than a series of ad hoc measures without a coherent diagnosis.
A well-prepared audit and modernization plan help to organize not only the technology but also the technical rationale: what caused the problem, what solutions were chosen, what parameters will be monitored, and how the investment is intended to reduce the risk of the issue recurring.
NOVA-KOMP in the modernization of existing systems
AK NOVA has been operating in the waste management sector since 2003 and has developed its proprietary NOVA-KOMP technology based on its experience in design, construction, and commissioning. The company not only builds new composting facilities but also modernizes and expands existing ones. In recent years, these projects have included, among others, the modernization and expansion of the composting plant in Sianów, the expansion of the biological section of the facility in Kraśnik, and earlier projects in Łuków, Krosno, and Łódź.
In practice, the greatest value for an investor lies not in a single technological component, but in the ability to combine diagnosis, design, paperwork, construction, and commissioning into a single process. This allows the solutions adopted during the conceptual phase to be immediately evaluated in terms of feasibility, costs, and future operation.
What should be the result of a well-designed modernization?
- a more stable and predictable course of the biological process;
- reducing uncontrolled emissions of process air and the risk of odor nuisance;
- better utilization of existing bioreactors and process space;
- greater control over the temperature, oxygenation, and humidity of the material;
- matching the air purification system to the actual load;
- easier operation and fewer actions taken "by feel";
- Consistent technical and formal documentation for the scope of changes being implemented.
From an audit to a solution tailored to a specific facility
There is no single modernization solution that works for every composting facility. Waste streams, the condition of the infrastructure, the facility’s surroundings, available space, administrative requirements, and operational procedures all vary. Therefore, the best first step is a technological audit, which will distinguish between symptoms and root causes and identify where the investment will have the greatest impact.
AK NOVA combines expertise in technology, design, environmental consulting, and general contracting. This enables the company to carry out modernization projects from problem identification, through concept development and documentation, all the way to implementation, commissioning, and operational support.
If your facility is operating at the limits of its capacity, the number of odor complaints is increasing, or the biological process requires an ever-greater number of interventions, it is worth starting with a technical audit. The AK NOVA team can analyze the existing system, identify its actual limitations, and develop a range of modernization options.
Frequently Asked Questions
Does modernizing a composting facility always require expanding the facility?
No. The scope depends on the identified bottleneck. In some plants, the desired effect can be achieved by adjusting ventilation, control systems, feed preparation, or air purification. In others, structural modifications or an increase in process space will be necessary.
Will a biofilter solve the odor problem on its own?
A biofilter is an important component of post-process air purification, but its effectiveness depends on proper air intake, gas parameters, the condition of the filter media, and the overall process operation. If the problem stems from anaerobic zones or an unstable feed, the biofilter alone will not eliminate the cause.
What parameters should be monitored during the process?
Key factors include, among others, the temperature, oxygen content, and moisture content of the material, as well as the operating parameters of the ventilation system. The scope of monitoring should be tailored to the technology and operating procedures of the specific installation.
Can the modernization work be carried out while the plant is operating normally?
It is often possible to carry out the work in stages, section by section, but this depends on the production layout, safety considerations, and the required process continuity. The schedule should be prepared on a case-by-case basis.
Does every modernization require a new environmental decision?
It is not possible to apply a single rule to all facilities. The obligations depend on the scope of the changes and the classification of the project. Before beginning implementation, a case-by-case legal and regulatory analysis must be conducted to determine the required decisions or permit updates.