Wastewater Treatment Plant Modernization

Treated wastewater from various sources can be used for agricultural and industrial purposes, ensuring the most efficient use of water resources.

This became possible thanks to advanced technologies and equipment used today in the framework of the modernization of the WWTP.

According to the World Bank, access to clean water remains one of the greatest challenges for humankind.

Arid regions of the world such as Southern Europe, the Middle East and Africa will need innovative solutions for the treatment of domestic and industrial wastewater in the coming decades to meet growing needs.

Many countries have already suffered from the misuse of groundwater, desertification and the intrusion of seawater into aquifers.

Using modern water treatment technologies to irrigate fields and improve agricultural efficiency will be critical to the development of these countries.

SI, together with international partners, offers financing, development and implementation of innovative technologies in the field of water treatment and desalination, as well as contributes to improving the efficiency of >wastewater treatment plants and ensuring the safety of consumers around the world.

We offer the following technical solutions:

• Modernization of equipment for mechanical filtration.
• Installation of innovative systems for biological wastewater treatment.
• Installation of reverse osmosis equipment for water desalination.
• Improving energy efficiency and introducing cogeneration technologies.
• Installation of fiberglass pipes for wastewater treatment plants.
• Modernization of equipment for water ozonization and disinfection.
• Automation of water treatment facilities.
• Installation of HVAC systems, etc.

Our company is ready to offer a full range of services related to the reconstruction or modernization of the WWTP, including project financing, financial modeling, engineering design, equipment production and installation, trial operation and training of the customer's personnel.

Contact SI representatives to find out more.

Improving the energy efficiency of wastewater treatment plants

Urbanization and population growth require quality wastewater treatment services.

The expected higher concentration of pollutants in wastewater determines the need for the construction of more advanced facilities using modern water treatment technologies or modernization of wastewater treatment plants using new energy-intensive equipment.

This will inevitably lead to an increase in the energy consumption of wastewater treatment plants if sufficient efforts are not made to optimize the energy efficiency of the equipment.

The results of a number of European studies show that the most important energy consumer at WWTP is the activated sludge aeration equipment. It accounts for 40-80% of electricity consumed in wastewater treatment plants. Sludge conditioning and dewatering also requires a lot of energy.

Equipment for primary wastewater treatment consumes significantly less energy compared to installations for fine treatment.

This is largely determined by the type and amount of pollutants removed, as well as the required water quality set by the regulators.

Improving the energy efficiency of wastewater treatment plants requires an understanding of the load structure and tariffs. The effluent entering the facility can be stored for a certain period, and the water treatment can be postponed to that part of the day when electricity prices are low.

Before starting the modernization of the WWTP in order to increase the energy efficiency of the equipment, it is important to analyze the baseline level and structure of energy consumption.

The energy audit will show which processes require energy and in what quantities.

The next step is to implement active and passive energy efficiency measures. Passive measures are defined as easy-to-implement actions, while active measures require significant changes to existing equipment and processes, including expensive automation and optimization.

The last step is energy reporting and monitoring, through which the wastewater treatment plant operator can set targets for future energy efficiency measures and identify key performance indicators for the implemented measures.

Domestic wastewater is mostly contaminated with organic and nutrient substances (nitrogen and phosphorus), while industrial wastewater can contain a wide range of pollutants, requiring a customized approach to equipment engineering and energy efficiency management.

General approach to improving the energy efficiency of WWTP

Experts identify several energy saving options that can be applied to wastewater treatment plants.

These include replacing motors and filtering systems with more efficient ones, introducing automatic control of HVAC and lighting systems, and others.

In addition, a reduction in energy consumption can be achieved by installing a SCADA control and data acquisition system to manage the energy consumption of WWTP and cogeneration.

Energy management measures at the WWTP are largely related to the operation of numerous powerful pumps. The use of more efficient motors and frequency drives can be considered among the directions of equipment modernization.

Another measure is optimization using specialized software.

Regular, proper maintenance helps keep the motor, pump, and entire pumping system running efficiently.

Additional options for efficient energy management include HVAC control and high-performance lighting installations. The provision of energy efficient lamps and systems for UV disinfection and water pretreatment are also noteworthy.

Other measures for the modernization of wastewater treatment plants

The most suitable areas for energy management in wastewater treatment are the aeration and pumping stages.

This includes aeration of water for biological treatment and aerobic decomposition, as well as pumping of activated sludge.

WWTP modernization measures provide significant energy savings at pumping stations for inlet and outlet wastewater streams.

As with drinking water treatment plants, the use of highly efficient motors or frequency drives is a common measure for improving energy efficiency.

Dissolved oxygen control and management is the key to energy efficiency.

Due to oversized equipment, inefficient processes or lack of control, the amount of air supplied to the aeration pools may be greater than is necessary to properly mix the streams and maintain biological activity. In addition to excessive energy consumption, over-aerated wastewater leads to sludge problems due to entrainment of solids in the stream.

The transition from coarse bubble aeration of water to the use of modern equipment with fine bubbles can reduce energy costs in this process by at least 25%. Controlling the aeration system requires the installation of properly sized dissolved oxygen sensors and blowers at an appropriate distance from each other.

Choosing the right type of pump and blower is also extremely important for improving the energy efficiency of the entire process. A common approach is to place a large number of diffusers at the inlet to aeration basins where the organic load is highest. Thus, aeration satisfies the demand for dissolved oxygen to a greater extent, providing more air at the beginning of the process and less at the end, where the ratio of nutrients to microorganisms is relatively low.

Another energy saving option is the use of intermittent aeration, including reducing equipment runtime or power reduction.

This method requires temporarily stopping air supply to a specific aeration zone or cycling air from one zone to another.

The cycle time can be automatically controlled based on the dissolved oxygen concentration.

The amount of oxygen required to maintain biological processes in aeration basins should correspond to the concentrations of organic matter and ammonia in wastewater entering the wastewater treatment plant. For example, at municipal WWTP, oxygen demand decreases at night and reaches its peak in the morning and evening.

In addition to changing oxygen demand, the efficiency of oxygen transfer in a pool depends on changes in air and water temperature, concentration of solids and surfactants, etc. Therefore, automated control of the level of dissolved oxygen can lead to significant energy savings in wastewater treatment.

When planning WWTP modernization, so-called leveling pools can be used in order to reduce energy costs.

These pools make it possible to postpone the actual water treatment process for periods of time with low energy consumption.

Another good opportunity for energy management in wastewater treatment plants is the process of removing particulate matter from wastewater. The use of equipment that more efficiently dewaters the sludge significantly reduces the overall cost of wastewater treatment.

Systems for using sludge as fuel for cogeneration have long been developed in European countries, providing additional savings during peak periods.

The methane from the anaerobic digestion of sludge can be used for cogeneration or heating to save energy in wastewater treatment plants. At obsolete WWTPs, gas flaring leads to the loss of valuable methane, which can be used to generate electricity.

The implementation of innovative measures to improve the energy efficiency of wastewater treatment plants requires detailed technical expertise.

If you are planning a modernization or expansion of WWTP, please contact us for advice.

Modern principles and technologies of wastewater treatment

Wastewater treatment at WWTP usually includes mechanical and biological stages.

The aim of mechanical treatment is to remove large impurities from the water. It is claimed that at this stage up to 70-80% of the total amount of insoluble substances is separated.

Organic pollutant levels are also reduced by about 40-50%.

The next step is chemical and / or biological wastewater treatment. Often, after biological treatment, additional measures are provided before water is discharged into natural reservoirs. This is due to increased environmental requirements to protect water bodies and ensure the reuse of water for agricultural or industrial purposes.

In most cases, biologically treated wastewater still contains biodegradable organic matter.

Among these substances are mineral oils, pesticides and others.

One of the most important technical problems is the high content of nitrogen and phosphorus, which can lead to a decrease in dissolved oxygen in natural water bodies and their secondary pollution.

Usually, up to 40% of nitrogen and phosphorus in water is removed using standard wastewater treatment technologies, but this figure varies.

Basic wastewater treatment methods

Mechanical, physicochemical, chemical, biological and other methods are used for wastewater treatment.

One of the commonly used purification methods is multi-stage filtration of biologically treated water.

For this, high-tech filters of various types are used, including drum mesh filters.

To achieve a higher degree of wastewater treatment and removal of fine suspended particles, dissolved inorganic substances, organic colloids and others, wastewater is often subjected to chemical coagulation, followed by sedimentation and filtration.

Ferric chloride, lime, aluminum sulfate or polyelectrolytes are mainly used as coagulants. The use of different flocculants is also recommended to achieve better chemical deposition.

When using coagulation methods for wastewater treatment, it should be borne in mind that this method increases mineralization, and the resulting sludge has a high content of aluminum and iron hydroxides and a very high humidity up to more than 98%.

The modernization of the WWTP may include the installation of highly efficient adsorption equipment.

ADSorption is considered one of the most effective methods for fine wastewater treatment in cases where a large amount of dissolved organic matter is present.

Adsorption technologies are ideal for removing stubborn organic substances that are not biodegradable, such as lignin, proteins and other substances responsible for the specific color and unpleasant odor of waste streams.

Adsorption processes are considered suitable for the recovery of valuable substances that can be used for industrial purposes.

The modernization of equipment in this direction contributes to the extraction of new products and an increase in the company's economic performance.

Modern technical solutions for the removal of nitrogen and phosphorus

Agricultural and domestic wastewater is usually rich in nitrogenous substances, the percentage of which can vary widely.

Highly efficient nitrification and denitrification processes are used to remove them. In practice, advanced physicochemical methods such as ion exchange are also used. It is also possible to use adsorption by activated charcoal with preliminary chlorination, ozonation, reverse osmosis, etc.

During nitrification, ammonia nitrogen is oxidized to nitrites and nitrates by atmospheric oxygen.



This occurs with the assistance of specific nitrifying microorganisms and requires the construction of special bio-pools and other equipment.

For nitrification and denitrification processes, various technological schemes are used, such as preliminary denitrification, simultaneous denitrification, denitrification stage with methanol, combined denitrification, and so on. For the simultaneous removal of nitrogen and phosphorus from wastewater, bioreactors with suspended biomass and attached biomass can be used.

Domestic wastewater usually contains significant amounts of phosphorus, most often in the form of orthophosphates, polyphosphates and phosphorus-containing organic compounds. During wastewater treatment, phosphorus compounds are constantly transformed.

Usually polyphosphates and organic phosphates are converted to orthophosphates, and some inorganic phosphates are used in metabolic microbiological processes.

At the outlet of the wastewater treatment plant, 80-90% of the contained phosphorus will be in the form of orthophosphates.

Chemical coagulation equipment can be used to remove them.

Biological methods can be used to remove phosphorus from water. The activated sludge, passing through many alternating anaerobic and aerobic phases, releases dissolved phosphates under anaerobic conditions. Traditionally, the main advantages of biological phosphorus removal methods are low cost and high efficiency.

Biological lakes are considered suitable for the removal of some contaminants.

This requires the construction of huge artificial structures, inside of which ideal conditions for natural biological processes are created.

If you are interested in the implementation of innovative biological wastewater treatment methods, our engineers are ready to develop for you a customized WWTP modernization project. Contact our consultants to find out more.

Removing phosphorus from wastewater: new business opportunities

Phosphorus is a key element for fertilizer production and for improving agricultural efficiency on a global scale.

At present, it is mainly produced from phosphorite, the deposits of which are concentrated in several exporting countries such as Morocco, China and the United States.

On the other hand, the irrational use of phosphorus and the leakage of phosphorus-containing fertilizers, detergents and wastewater into natural water bodies lead to eutrophication. In recent years, more and more attention has been paid to the development of technologies for removing phosphorus from waste streams and reusing its products. There are currently over 70 phosphorus recovery plants operating in Europe, North America and East Asia.

In wastewater treatment, phosphorus is usually removed by chemical or biological methods.

As a result, this element accumulates in the sludge, which undergoes anaerobic decomposition, dehydration and incineration.

Thus, phosphorus can be recovered from effluents removed during dewatering, as well as from treated sludge or ash.

Equipment for the removal of phosphorus from the liquid phase ensures the extraction of up to 50-70% of the element, after which the remaining amount of phosphorus is removed with the sludge. Usually in this phase about 20-40% of phosphorus is extracted.

The resulting product is struvite (magnesium ammonium phosphate) or calcium phosphate. The advantage of the approach is that it can be easily integrated into existing wastewater treatment plants. Thus, the modernization of the WWTP for phosphorus recovery opens up new economic opportunities.

Since up to 95% of the phosphorus entering the wastewater treatment plant is deposited in the sludge, the potential for its recovery from the sludge is the highest.

The interest in modernizing equipment in this area is growing all over the world.

The sludge from wastewater treatment plants is also used directly as fertilizer, but this is associated with environmental risks due to the high content of heavy metals, pathogenic microorganisms and organic pollutants. Therefore, technologies for extracting phosphorus from sludge must cope with these pollutants. The most common method is crystallization, a chemical technology using a strong base or acid.

When recovering phosphorus from sludge ash in wastewater treatment plants, it is important to incinerate the ash separately from other waste. Co-combustion significantly reduces the concentration of phosphorus in the residual ash and increases the concentration of pollutants.

During incineration, the volume of sludge is significantly reduced, while organic pollutants and pathogens are completely removed.

The advantages of this technology include a small ash volume.

Product quality is highly dependent on the disposal processes used. If chemical removal of phosphorus is used, high levels of aluminum and iron can adversely affect product quality and future use.

Thermochemical methods are used to reduce the content of heavy metals and increase the bioavailability of phosphorus in the ash formed during the combustion of sludge at the WWTP.

Most processes for the recovery of phosphorus from wastewater involve the release of calcium phosphate or struvite by precipitation / crystallization. Calcium phosphate, or hydroxyapatite, is a product whose properties are comparable to those of phosphorite. For this reason, it should be borne in mind that the kinetics of precipitation of calcium sulfate plays a more important role than factors related to thermodynamic equilibrium.

Spontaneous precipitation from solution is usually not observed at all, unless very strong supersaturation occurs.

However, separation of calcium phosphate can be achieved by adding crystalline particles such as sand and calcium silicate hydrate, which initiate the precipitation / crystallization process.

The economic benefits of phosphorus recovery

Calcium phosphate is similar to phosphorite, so it can be used as a raw material in fertilizer production.

Growers can also mix calcium phosphate with other nutrients and apply it to the soil as fertilizer.

Removal of phosphorus from municipal wastewater by crystallization is the subject of numerous European studies. This technology is widely used in the modernization of wastewater treatment plants. Modern equipment produces more than 1 kg of magnesium-ammonium phosphate from 100 м³ of municipal wastewater with a phosphate ion concentration of 7 mg / l (recovery efficiency 55%).

The economic benefits of this technology are mainly determined by the operating costs and revenues from the commercialization of the final product.

According to a recent study, the operating costs for phosphorus recovery range from £ 2 to £ 8 per kg of phosphorus, depending on the specific process.

However, the lower the concentration of phosphorus in the water, the higher the cost of upgrading equipment. Before implementing technologies for the recovery of phosphorus from municipal wastewater, it is important to carefully analyze the characteristics of a specific type of wastewater.

Although the economic benefits of crystallizing phosphorus from wastewater are usually limited to product commercialization, there are many other benefits to this approach. Phosphorus recovery provides an alternative solution for agriculture and also helps prevent water pollution. Therefore, the environmental benefits should be considered along with the economic viability of the project.

If you are interested in the recovery of phosphorus from wastewater, please contact our consultants.

Together with our partners, we are ready to develop the optimal technical solutions for the modernization of wastewater treatment plants for your business.

Application of nanotechnology for wastewater treatment

Potential applications of nanotechnology in wastewater treatment include quality improvement, monitoring and pollution prevention.

In particular, nanotechnology aims to improve water quality and the availability of water resources.

This group includes a number of innovative solutions, including advanced filter media that enable more widespread recycling and desalination of water for domestic, agricultural and industrial use. State-of-the-art engineering solutions for WWTP modernization today include next-generation sensors specifically designed to detect the presence of biological and chemical contaminants at very low concentrations.

Membrane processes are considered a key element of modern water purification and desalination technologies.

The development of nanomaterials, including carbon nanotubes and dendrimers, is helping to develop more cost-effective solutions.

Nanostructured filters are increasingly used in this sector, where carbon nanotubes and nanomatrices are the basis of nanofiltration. Nanoreactive membranes, where functionalized nanoparticles facilitate filtration, can increase the efficiency of the process by several times.

Advances in macromolecular chemistry, such as the synthesis of dendritic polymers, create opportunities for improving existing and developing new technologies for filtering and purifying water contaminated with various organic solutes and inorganic anions.

Nanotechnology is driving the development of a new generation of chlorine-free biocides.

Among the most promising antimicrobial nanomaterials are nanoparticles of metals and metal oxides, in particular silver and titanium dioxide, which are used for photocatalytic water disinfection.

Nanotechnology for the modernization of wastewater treatment plants

In many developed countries, natural water bodies are highly polluted as a result of human activities, which poses a serious risk to public health.

Contaminated water purification involves the process of removing, reducing the concentration or neutralizing pollutants that threaten humans or the safety of ecosystems.

Modernization of WWTPs using nanotechnology is one of the areas in which we have been able to concentrate significant investments in recent years.

Different wastewater treatment methods in this area are used for different types of pollutants, and there is no one size fits all solution. Given the complex chemistry of polluted waters, it is usually necessary to use a combination of technologies to reduce the concentration of harmful agents to acceptable levels.

Old WWTPs, which rely on traditional mechanical installations (sand traps, coarse membrane filters), do not provide an adequate level of wastewater treatment in today's environmental realities.

Nanotechnology provides a much more efficient solution for quickly, efficiently and economically removing toxic contaminants from water. Among the innovations in this area are nanomaterials with improved selectivity for the removal of heavy metals and other industrial pollutants.

The use of nanotechnology provides many benefits, including higher reactivity, larger coverage area and active binding of contaminants).

A wide range of nanofilters and innovative materials are used today at all stages of ground, surface, industrial or drinking water purification, each of which performs specific functions.

Among the nanomaterials and nanoparticles used in wastewater treatment, we can name zeolites, carbon nanotubes, self-forming monolayers on mesoporous supports (SAMMS), biopolymers, monoenzyme nanoparticles, zero-valent nanoparticles, bimetallic nanoparticles and much more.

Thanks to close cooperation with leading scientific institutions in United Kingdom and other European countries, we can offer unique technical solutions for your business, ensuring the achievement of a high degree of wastewater treatment with minimal investment.

Contact SI consultants to find out more.

Installation of fiberglass pipelines

Fiberglass pipes are made from fiberglass reinforcement cast in a cured thermosetting resin.

This composite structure can also contain fillers in the form of various aggregates, granules or plates, thixotropic agents or pigments.

By choosing the right mix of resin, fiberglass and fillers, a manufacturer can create a pipe that offers a unique combination of performance and price for a wastewater treatment plant. Due to the variety of materials used for the production of fiberglass pipes, they have received many names, including FRP, GRE, GRPP and others.

Fiberglass pipes are classified according to the type of manufacturing process, as well as the chemical composition of the thermosetting resin (epoxy, polyester, vinyl ester resin).

Fiberglass pipes were first introduced to the market in 1948.

They found their first application in the oil and gas industry, where fiberglass is used as a corrosion-resistant alternative to steel pipes or rare metals.

In the late 1950s, larger diameter fiberglass pipes began to appear, and their use in the chemical industry gradually increased due to the inherent corrosion resistance of the polymer material.

Since the 1960s, fiberglass pipelines have been used for water supply and sanitation. They combine the advantages of durability, strength and corrosion resistance, eliminating the need for interior finishing, exterior coating (painting) and cathodic protection of pipelines.

Many experts believe that fiberglass pipes are the best solution for transporting industrial water.

They are often used in desalination plants, in wastewater treatment plants, as well as for transporting cooling water in power plants, in the construction of storm sewers, etc.

GRP piping systems offer exceptional engineering flexibility as there is a wide range of diameters and fittings, and the ability to customize products. In fact, WWTP operators can order the installation of fiberglass pipelines with a diameter of 20 mm to 3600 mm and more.

The mechanical strength of these pipes is determined by the amount, composition and orientation of the glass fibers. In general, the strength of the pipe increases as the amount of fiberglass incorporated increases.

Fiberglass materials are available in a wide variety of chemical compositions to provide flexibility for different situations.

The orientation of fiberglass in pipes can be different. With one-sided orientation, the strength will be maximum in the direction of the fibers. In this case, the fiber content can be up to 80% by weight.

When the orientation is bidirectional, some fibers are angled.

This provides different strength values, determined by the number of fibers in each direction.

The multidirectional (isotropic) orientation provides nearly the same strength in all directions.

The second component of fiberglass pipes is the resin, which is selected based on the chemical, mechanical, thermal properties and processability of the materials. Thermosetting plastics are polymer systems that cure when exposed to heat or chemical additives.

For the production of fiberglass pipes, polyester and epoxy resins are used. Polyester resins are often used to make large diameter water and sewer pipes. They are highly resistant to water, chemicals and acids. The polyester resin is solid and dissolves in styrene monomer, which is crosslinked to give the final structure.

Epoxy resins are mainly used for the production of smaller diameter pipes for transporting water, condensate, hydrocarbons, bases or dilute acids.

Epoxies generally tolerate higher operating temperatures than polyesters, up to 110 ° C.

The type of curing agent used is critical to the quality of epoxy resins, as this chemical affects the properties of the composite material. When choosing a specific product for the modernization of wastewater treatment plants, an engineering company takes into account the operating conditions, features of the technological process, customer requirements and the expected cost of equipment.

Advantages of fiberglass pipes for WWTPs

GRP pipes are corrosion resistant both internally and externally and this applies to a wide range of fluids.

They also have a good strength-to-weight ratio that is higher than some types of steel.

Fiberglass composite piping systems are lightweight. Their weight usually reaches about 15% of the weight of similar steel products or 10% of the weight of similar reinforced concrete products.

Fiberglass pipelines do not conduct electricity. Several European manufacturers also offer special conductive fiberglass products for the construction of equipment that requires static electricity dissipation when transporting flammable liquids.

Fiberglass composites are easy to process and capable of maintaining the critical tolerances required for most structures and piping. They meet the strictest criteria in terms of material hardness, dimensional tolerances, weight and cost.

This pipeline is easy to maintain because it does not rust, is easy to clean and requires a minimum level of environmental protection.

All GRP pipes are watertight and can be used without repair for decades when laid underground. The service life and aggressive environmental conditions are taken into account in the engineering design of pipelines.

GRP piping for wastewater treatment plants must be resistant to a wide range of chemicals. Their chemical resistance is highly dependent on the resin used. While other factors such as manufacturing method can also have an impact, the resin is the main factor.

The heat resistance of fiberglass pipes also largely depends on the resin matrix.

The permissible upper operating temperature limit is determined by the chemical environment and the stress state of the pipeline system.

Chemicals are usually more aggressive at higher concentrations and elevated temperatures.

However, standard operating temperatures (below 35 ° C) do not affect this material.

When planning the modernization of the WWTP using fiberglass pipelines, one should take into account some of the disadvantages of this material. For example, its coefficient of thermal expansion is higher than that of metal pipes. This must be taken into account in the engineering design of the system, ensuring the expansion and contraction of pipes, especially when laying underground.

Most of the resins used in the production of fiberglass are degraded to some extent by ultraviolet light.

However, this is a superficial phenomenon and does not affect the structural integrity of the pipeline.

The effect of UV radiation can be significantly reduced by adding stabilizing fillers and pigments to the resin.

Other disadvantages include lower impact resistance due to the brittle nature of thermosetting resins, the need for careful preparation for installation due to more specific joint methods, and the need to build special supports for overhead installations due to the flexibility of the material.

However, this material is widely used in the modernization of wastewater treatment plants.

Modern HVAC systems in wastewater treatment plants

In wastewater treatment plants, the efficiency of heating, ventilation and air conditioning (HVAC) systems can be a key factor in determining the outcome of treatment processes or potential environmental pollution.

Maintaining optimal temperatures, pressures and air flows helps to quickly remove contaminants from the incoming wastewater stream.

In addition, HVAC systems play a primary role in combating unpleasant odors from wastewater treatment. According to a number of studies, odor control methods are undergoing significant changes due to the growing variety of chemicals used in different industries.

Effective odor control

Odor control is one of the most important and most challenging aspects of wastewater treatment.

Bad smells are often the cause of complaints from both workers and the local community.

The source of odor in wastewater treatment is mainly the processes of anaerobic decomposition of organic compounds.

Hydrogen sulfide is a typical by-product of these reactions and is characterized by a strong unpleasant odor. Due to its low water solubility, hydrogen sulfide is released into the atmosphere.

Amines and mercaptans are two other types of strong odor substances emitted from wastewater treatment. These compounds contain nitrogen and sulfur, respectively, and their unpleasant odor is felt even at very low concentrations.

The intensity of the odor in wastewater treatment plants can increase due to weather conditions. Temperature differences, wind speed and direction are some of the factors affecting the distance foul-smelling gases can travel. In summer, due to increased water consumption and high temperatures, the intensity of odors is usually higher.

Equipment maintenance as well as the expansion of cleaning processes can also significantly affect gas emissions.

Modernization options

WWTP modernization projects to better control odor requires a comprehensive professional approach and preliminary research.

The first step for effective odor control at WWTP is to identify the source. In practice, the problem can be found at every stage of treatment – from open wastewater at the inlet of the pumping station to the filtration stage.

There are many odor control technologies available on the market, but there is no one-size-fits-all solution yet. Some businesses use deodorizing systems designed to combat volatile organic compounds in the air. In other cases, special chemicals are added to the wastewater, which react with compounds responsible for the formation of odor gases.

One of the most common solutions is to use HVAC systems that maintain constant negative pressure over the odor source.

These systems are very effective in preventing emissions, and their main disadvantage is that the intake air must be cleaned before it is released.

Wet scrubbers can be used to remove virtually any water-soluble contamination. Besides hydrogen sulphide and organic gases, this equipment is also very effective for ammonia removal. Multi-stage wet scrubbers allow the use of different chemical solutions for each stage of the cleaning process and eliminate the emission of a wide range of pollutants.

Among the main advantages of a wet scrubber are the high reliability and flexibility provided by the use of various chemicals. One of the challenges in the design and operation of wet scrubbers is to minimize the cost and quantity of chemicals used without compromising air purification efficiency.

Biofilters can be used for biodegradable water-soluble contaminants present in WWTP.

These devices are very effective in removing sulfur-containing compounds such as hydrogen sulfide, organic sulfides and mercaptans.

The two main problems with biofiltration systems are water level stability and maintaining a continuous process. Over time, the filler in biofilters thickens, which leads to a decrease in air flow and the release of uncontrolled odors. In addition, the biological population in biofilters can degrade with significant changes in environmental conditions.

Adsorption systems with activated charcoal are the simplest solution for odor control in wastewater treatment plants. No additional chemicals are added here. In addition, no sensitive biological processes are used in adsorption systems.

Selecting the optimal odor control technology and developing customized HVAC solutions allows us to achieve excellent results when modernizing wastewater treatment plants.

Computerization and automation of wastewater treatment plants

Growing environmental issues related to wastewater treatment, including tightening regulations, deteriorating infrastructure and the need to improve efficiency, are forcing WWTP operators to transform their traditional ways of working.

Companies must be more active in adopting innovative technologies that can provide immediate value and long-term profits. This trend is driving the need to use information systems to help wastewater treatment plant operators better manage plant assets and make better operational decisions in real time.

In recent years, the main approach in response to the need to improve operational efficiency has been the widespread adoption of automation tools, including solutions with remote monitoring and computer control, such as SCADA systems or smart controllers.

Operators need real-time information about what is happening at the wastewater treatment plant.

They need to receive reliable and up-to-date information in order to make quick and accurate decisions. There is also a need for more extensive automation.

Wireless sensors and maintenance

Wireless technologies are rapidly advancing, allowing, among other things, to improve information flow and reduce operating costs.

Modern wireless devices offer significant advantages over cabling in certain applications, especially where long distance communications are required.

The latter is considered a common condition in water collection and distribution systems.

Modernization of WWTPs using wireless networks reduces installation costs, provides flexibility, facilitates data collection, and can improve site security.

Wireless SCADA systems can facilitate the collection of process and asset information from remote sites where wiring or manual data collection would be too expensive or time consuming. The performance and speed of wireless systems are increasing, and their designers are providing the network security solutions needed for a wide variety of applications.

As safety issues become increasingly important, wastewater treatment plant operators need access to real-time data on the quality of treated water supplied to consumers. In order to protect critical assets from pollution, it is important to install systems at all sites that can reliably track and monitor these assets 24/7 without human intervention.

The continued deterioration of WWTP infrastructure in many countries around the world remains a major challenge for maintenance managers who must provide key activities such as comprehensive diagnostics, calibration and real-time monitoring.

In recent years, technological advances in information gathering techniques and a wealth of new digital tools have helped improve maintenance work and optimize its efficiency. It is important for operators to invest in technological and information improvements.

Today, companies are increasingly focusing on strategic maintenance — a combination of predictive, proactive and reactive support strategies based on the needs and resources of a particular facility. By applying the appropriate actions to the right asset at the right stage in its life cycle, operators optimize the efficiency of the water treatment equipment.

This strategic approach helps the business prepare maintenance budgets, establish expected asset reliability, and schedule replacement equipment and components.

For many wastewater treatment plants, it makes sense to divide the asset management activities into stages, starting with the most critical equipment and systems. This step-by-step approach is especially effective for small companies where limited investment resources require limited actions, from small investments to adding innovative technologies at the right time.

SI can help you upgrade your wastewater treatment plant and create the optimal strategic equipment maintenance plan based on your specific business needs and financial resources.

Automation to improve energy efficiency

Energy costs represent a significant cost item for any wastewater treatment plant.

This requires close attention, as tighter budgets and rising energy costs force them to change their way of working.

Companies today need new methods to regulate energy consumption and water quality, based on digital monitoring tools and new management algorithms. Efficient energy management is no longer just an opportunity, but a strategic imperative for wastewater treatment plant operators.

In the water sector, most of the electricity is consumed by the motors of pumps and compressors. By installing smart automation devices where electricity is converted into mechanical energy, companies can dramatically improve energy efficiency.

Another way to maintain or optimize equipment performance is through the use of modern motor controls.

For example, variable speed drives can reduce energy consumption during operation.

Other optimization tools such as energy efficient gears, motor controllers and software can also provide immediate cost savings without compromising water quality.

Latest WWTP automation trends

The use of automation tools in the wastewater treatment process has two main functions: information collection and process control.

As for the first of these functions, this is a fairly high level of automation.

In modern conditions, data for thousands of variables (there are objects that analyze more than 30,000 variables) are collected online by SCADA systems.

The analysis of this data is a standard and integral part of water purification and control operations.

The level of WWTP control automation is less developed and is often limited to a few separate process control loops. The potential for large-scale automation at the level of an individual wastewater treatment plant today lies in the coordination of various autonomous processes.

The efficient operation of the WWTP depends on the working equipment.

Communication systems play an increasingly important role in the management of wastewater treatment plants. The software is not only based on appropriate control algorithms, but also includes huge databases, communication systems, data collection systems, and user data display interfaces.

When planning the modernization of the WWTP, it should be borne in mind that today automation is accepted as a standard component.

These activities require a fairly high initial cost, but quickly pay off due to the results of the work.

The modern control system of the wastewater treatment plant includes a monitoring system that sends key parameters to SCADA (dissolved oxygen, reagent doses, process phases, start and stop of sedimentation in bio-basins). The use of such control systems at plants shows good profitability, and the payback period is usually up to five years.

Effective management, although partly within the framework of the whole system, is actually a very difficult task.

Currently, problems arise mainly with data (assessment, management, analysis) and administration, not with algorithm.

Further developments in this area will be based on the advanced data communication tools available today. Modern SCADA systems are already using the Internet, which provides almost unlimited possibilities for remote data assessment and decision making.

The question is whether wastewater treatment plants can afford it.

Wastewater treatment plant modernization: our services

Every day, WWTP operators face new challenges, including stricter environmental legislation, rising energy costs and the emergence of new pollutants.

All of this increases operating costs and requires more efficient business solutions.

SI partners with reputable scientific institutions, international associations, equipment manufacturers and financial institutions to provide each client with the optimal solution.

Our company, together with partners from all over the world, participated in the implementation of investment projects in many countries, proving the advantages of an innovative and comprehensive approach.

Table: main directions of modernization of wastewater treatment facilities.

Typical problems	Our solutions
High power consumption	Energy efficiency measures for WWTP include the installation of new engines and pumping systems, the installation of new equipment for aerating activated sludge, the introduction of computerized control systems and other measures.
Insufficient automation	Modernization of SCADA systems and widespread use of wireless sensors that control all key parameters of the technological process; computer control in real time.
Excess sludge production	Innovative technologies for sludge drying and combustion, including the use of sludge in cogeneration systems; sludge processing for the production of valuable materials.
Environmental impact	Modernization of filter blocks, development of new methods of chemical or biological wastewater treatment in order to improve the quality of the process.

Our company offers financing, comprehensive assessment and development of customized >engineering solutions to solve any of the problems of the wastewater treatment plant operators that you face every day.