Biologycal Oxygen Demand (BOD)

Biologycal Oxygen Demand (BOD)

What is BOD?

Biological oxygen demand (BOD), also called biochemical oxygen demand, The BOD5 value indicates the amount of oxygen that bacteria and other tiny living beings consume for 5 days at a temperature of 20 ° C in a water sample for the aerobic degradation of the substances contained in the water. The value BOD is thus an indirect measure of the sum of all the biodegradable organic substances in the water. The value BOD indicates the amount of dissolved oxygen (mg / l) that is required during a certain time for the biological degradation of the organic substances contained in the wastewater. This value is an important parameter to assess the degree of load that residual water represents for the environment (receiving channel). As the substances contained in the wastewater are degraded in the receiving channel by the bacteria present there, the oxygen is partially or totally eliminated from the water. When these limit values ​​are exceeded, it can cause the death of living beings that breathe oxygen (crabs, fish, etc.).

The BOD is a pollution parameter to evaluate the quality of effluent or wastewater.
Drinking water is also evaluated for organic matter, this is measured through Total Organic Carbon (TOC or TOC) instead of BOD.

The biochemical decomposition of organic substrates is carried out by microorganisms. In this case we are talking about aerobic bacteria, which need energy that they produce from oxygen to complete decomposition. The oxygen is consumed and as a result the level of oxygen dissolved in the water is reduced. If there is a large amount of organic matter in the water, the oxygen demand is also higher for decomposition to take place.

The quality of the water is controlled by the authorities to protect the health of the users and other effects of poor water quality. A high BOD level may indicate fecal contamination or dissolved organic carbon particles from different sources other than humans or animals. This kind of pollution can seriously affect human health and cause problems in industry.

It is of great importance that governments ensure a low level of BOD in the effluent water coming out of sewage plants, because it is in the public interest to have rivers, lakes and seas with a high level of dissolved oxygen.

How to measure the level of BOD?

There are two methods to measure the BOD level, both are empirical tests.

  • Method I: It is the most common method. A special bottle for BOD is filled to the brim with the water test. The test is left for 5 days at a constant temperature of 20 ° C in the dark. After 5 days the oxygen content is measured compared to the original value, the oxygen consumption during this period indicates the oxygen demand of the water.
  • Method II: If a very high BOD is expected or if other toxic or inhibitory substances are present in the water, the sample can be diluted at first. In this way you can avoid having too little oxygen present to break down organic substances. This would falsify the measurement result. As with Method I, a comparison of before and after values ​​now serves as a measure of oxygen consumption during the measurement period.

After 5 days the dissolved oxygen is measured, with which the BOD level can be calculated. Drinking water should have a concentration of less than 1mg / l after 5 days. The wastewater concentration is accepted around 20mg / l.

As the methods are empirical, the BOD indicator does not give absolute results. What the indicator provides is a good test comparison but does not give an exact measure of contamination. An alternative to BOD is COD – Chemical Oxygen Demand.

Anaerobic bacteria like SRB do not need oxygen in the water to survive. These microorganisms live on sulfur, so they cannot be detected by measuring the biochemical oxygen demand.


Physical Chemical Treatment

Mechanical separation of solid substances by filtration

Filtration separates solid substances from liquids. To do this, the mixture to be separated passes through a filter; in the simplest case, it can be made of paper. For technical applications, filters made of textile or metal fabric are mostly used. Sand filters, rotary sieves and cloth filters are also frequently used.

With the aid of filter systems, suspended organic and inorganic substances, sand and dust can be removed from the water. In wastewater technology, this mechanical separation process is used, among other things, for the dewatering of sludge in filter presses. In the treatment of water for industrial use and drinking water from surface waters, filtration is also applied; generally in a multi-stage process.

Membrane filtration is also a mechanical separation process. In this case, a membrane serves as the filter medium. This method is typically used to separate very small components.

Industrial massive water filtering mechanism.

Cleaning wastewater with membrane technology

With membrane filtration, dissolved and undissolved substances can be separated from waste water and concentrated. Thus, the separation is carried out under pressure; the membrane, with a given pore width, retains particles (eg molecules) from a certain size. The different processes are used for water treatment, for the cleaning of waste water, for the recycling of process water and for the concentration of recyclable materials for their recovery.

The micro filtration is used to separate particles, bacteria and yeast. It is used, among other things, for cold sterilization and the separation of oil and water emulsions.

The ultra filtration is an important process for treating drinking water and wastewater. It is used to separate particles, microorganisms, proteins and turbidity from water, among others, in the membrane bioreactor (MBR).

Ultrafiltration is used for example for cleaning recirculating water in swimming pools. Since the formation of clogging layers adhering to the membrane can be avoided quite well, existing sewage treatment facilities are increasingly being supplemented with an ultrafiltration called “polishing step”. In retrofitting older classic treatment plants, ultrafiltration can be inserted directly into or after the bioventilation tank to replace subsequent treatment steps or to increase the performance of biological wastewater treatment.

The nano filtration can separate viruses, heavy metal ions, large molecules and very small particles. This process is used in the softening of water and in the treatment of drinking water.

The osmosis inversa is an important step process the concentration of landfill leachate, in the treatment of drinking water in rural regions that are not connected to the mains, in seawater desalination or descaling water boilers in power plants. To do this, the concentration of dissolved substances in liquids is increased through a semi-permeable membrane, reversing the osmosis process with pressure: if the pressure is higher than the respective osmotic pressure, the solvent molecules diffuse on the side of the membrane on which the dissolved and less concentrated substances are found. This process is also used to obtain ultrapure water.

New carbon filter cartridge for house water filtration system isolated on white background.

Wastewater treatment by flotation

In flotation, substances dispersed or suspended in liquids are transported to the surface with the help of small gas bubbles, where they are removed with a removal device. Flotation processes are used in wastewater treatment to separate suspended oils, fats and fine solids.

The smaller the microbubbles, the better the particles or droplets settle. For this reason, dissolved air flotation (DAF) is frequently used in wastewater treatment technology. This has been noted for its proven efficiency and cost effectiveness. Flotation processes can be further enhanced by employing auxiliary means, such as manifolds, skimmers, regulators or pressure devices.

Close-up film of green algae on the surface of the water, preventing the flow of oxygen

Separation of solid substances by sedimentation

Sedimentation uses the force of gravity in sedimentation tanks to separate solid particles. A sedimentation tank is a flat tank with almost no current flow, especially for sedimentation processes. Solid particles settle to the bottom.

Sedimentation processes are used in multiple ways in wastewater treatment: undissolved substances are deposited in the primary settling tank. These form the primary sludge, which then thickens and becomes anaerobic in the digester. This generates digested sludge and digestion gas, which in its already clean form as biogas can be used to produce electricity and meet energy demand. Aerobically generated sewage sludge can also be introduced into the digester, after it has been separated by sedimentation from the residual water in the settling tank. Particles that are heavier than water can be separated from the liquid with the help of grit traps or sludge collectors.





Biologycal Treatment of wastewater

Anaerobic biological cleaning of wastewater with UASB process

The RAFA (upflow anaerobic sludge blanket – UASB) reactor method is frequently used for the biological treatment of industrial wastewater. With this process, large amounts of organic substances, such as dissolved sugars, proteins and fats, can also be removed from the wastewater.

These are chemically treated in a special reactor in the absence of atmospheric oxygen by microorganisms, transforming them into biogas. Biogas is a gas mixture that contains mainly methane and carbon dioxide. It can be used as an energy source in production; This generally generates power and heat in a cogeneration plant.

This special version of a biogas plant is mainly used for wastewater treatment in the food and beverage industry, citrus fruit production industry. and in the manufacture of paper and cellulose.

Aerobic biological processes for wastewater treatment

Wastewater cleaning with the MBBR process

The moving bed biofilm reactor (MBBR) process is a technology for the biological treatment of wastewater in which the necessary microorganisms grow as biofilm on a support material.

With the settlement of microorganisms on the surfaces of the filling medium, a large effective surface is generated. The aeration of the reactor ensures that the fluid is permanently mixed and thus sufficient contact of the substances in the waste water with the microorganisms is generated. It is also possible to apply the moving bed process with biofilm anaerobically; in this case, the mixing is carried out with the aid of pumps or with a stirrer.

Both the dominant transverse forces in the bioreactor and the substances in the wastewater influence the thickness and composition of the biofilm on the support material: the higher the content of organic substances in the wastewater, the faster the biofilm will grow.

Advantages of the MBBR process over the activated sludge process

Activated sludge processes have the disadvantage that, by removing the excess sludge, a part of the microorganisms that are in suspension is also removed. Despite the return of the recirculation sludge from the decanter, the microorganisms reach a relatively young age.

In the MBBR process, the microorganisms immobilized on the supports have a substantially longer life. In this way, microorganisms are established in the biofilm that have specialized in difficultly degradable compounds and that have very long generation times. In general, the cleaning process is more stable than activated sludge processes and peak loads can be collected better.

DAS Environmental Expert GmbH uses a support material that has an extremely high specific surface area and thus makes MBBR bioreactors particularly compact. The shape of the filling materials further prevents the support material from blocking, thus achieving a high capacity for continuous space degradation.

Our MBBR plants can be designed as a compact plant or as modular bioreactors. Modular reactors require much less space than conventional activated sludge plants. No excavations or underground works are required. With the corresponding technical process design, our MBBR plant can be built and operated as a denitrification reactor.

Reduced amount of excess sludge in the biofilm process

As in any biological process to degrade organic carbon compounds, an excess of sludge is also generated in the MBBR. In the biofilm process, the quantity is biologically conditioned, but it is clearly lower than in an activated sludge process of equal capacity. However, the already clean wastewater must be separated from the generated sludge after treatment in the MBBR. This can be done for example by sedimentation in a settling tank. In the case of an indirect discharge in another treatment plant, it is possible to evaluate the elimination of a sludge separation, if the capacity and design of the treatment plant allow it and if it can be ruled out that there are unwanted sedimentation processes in the path of transport.

Biological wastewater treatment with the membrane bioreactor (MBR)

The membrane bioreactor (MBR) can also be used for the oxidation and nitrification of organic substances in wastewater. The degradation of toxic substances takes place in this case in a bioventilation tank with a high concentration of sludge.

The separation of the purified water and the activated sludge is carried out by ultrafiltration with the help of the membranes of this reactor. Such a membrane filter module can also be integrated submerged into existing biological treatment phases; however, a separate reactor can be more easily maintained.

The MBR process is ideal for the biological treatment of highly polluted industrial wastewater. In addition, it is often used also for the subsequent clarification of domestic and communal wastewater and for the treatment of gray, rain and surface water.

Due to the small size of the membrane pores, bacteria and viruses cannot pass the membrane filter, so it retains germs. The quality of the water in the purification process thus complies with the EU Bathing Water Directive. Thanks to their compact shape, MBR plants can be designed in a modular way as a container, thus constituting a completely mobile solution. This makes them particularly suitable for limited time use.

Biological cleaning of wastewater with the bacterial bed reactor

In wastewater treatment with a trickle flow reactor (TFR), wastewater is sprayed onto a fixed bed. This consists of a very light fine-grained support material, which after a few days (depending on the respective conditions) grows with a highly active mixed population.

The water flows continuously from top to bottom through the filling material; conversely, the ambient air is supplied to the plant by a fan. Since the load of the support material is not within a closed body of water, little pressure is needed for this. Thus, in the case of TFR technology, a sufficient oxygen supply for microorganisms can be obtained with very little effort. Fully automatic regeneration takes place at regular intervals through which the mixed microbial population is rejuvenated and excess biomass is washed out of the system without causing a loss in yield. Fine sludge can continue to be drained and, depending on site conditions, can be taken to composting or soil conditioning facilities.

Biological wastewater treatment with the SBR process

Sequential biological cleaning (Sequenced Batch Reactor – SBR) is an activated sludge technology for the treatment of wastewater in two separate parts of the plant. A primary settling is first used for the mechanical retention of coarse substances. This also serves as a collecting tank from which the contaminated wastewater is transported to an activation and settling tank called the SBR tank.

There, the incoming wastewater is cleaned in a cyclical process. For this, activated sludge is used, which contains a large number of microorganisms that eliminate organic substances from the wastewater. To ensure good mixing and oxygen supply, the waste water is stirred at regular intervals by supplying air.

This aeration phase is followed by a resting phase without aeration. In this, the activated sludge is deposited on the floor of the facility. On the contrary, in the upper part of the SBR tank a zone of purified water is formed. From this area, the treated wastewater is extracted and led to a drainage channel or an infiltration plant. The excess sludge is removed from the reactor floor by means of pumps. This is sent back to the primary settling. Then the cleaning process starts again.


Wastewater Treatment Procedure

Wastewater Treatment Procedures

There are multiple best available technologies (BAT) procedures for wastewater treatment. Our main competences are the detailed study and conceptual development of this procedure for wastewater treatment.

We works with a wide range of biological and physicochemical procedures for wastewater treatment. Our team develops individual wastewater treatment methods for you, meeting all your needs and requirements.


Biological wastewater treatment

Biological treatment systems aim to degrade organic substances contained in wastewater and reduce ammonium and nitrate loads. Our technology for the biological treatment of industrial and sanitary wastewater offers you the most complete and modern range of biological methods of wastewater treatment. These can be applied flexibly and efficiently in different sectors of industry.

With biological processes for the treatment of wastewater, we help you to comply with the legally prescribed discharge values, to save burdensome supplementary fees imposed on large polluters, to achieve a more respectful production of the environment and to design more efficient processes through the reuse of water.

In most cases, biological processes are also the best solution in the paper and pulp industry, in laundries and in the textile industry, in companies in the food industry and in agro-industry. Biological wastewater treatment facilities are used to degrade organic substances and ammonium and nitrate loads.

Physical-chemical wastewater treatment

Often, the physical-chemical treatment of wastewater consists of sub-steps, beginning with a separation of coarse and fine substances. Depending on the task to be performed, the wastewater can be further treated using a chemical process. By intelligently and efficiently applying the most convenient method, our experts design the solution that best suits your specific needs.

Screens and sieves remove harmful solid substances from the water. This mechanical process separates, for example, diapers, hair, wet wipes and sanitary napkins from the wastewater stream. Before cleaning industrial wastewater, the sieves also capture textile fibers, paper labels, plastic debris or production waste, such as potato peels or other peel debris.

Depending on the scope of application, fine or coarse screens are used. These clean the water by means of bars arranged in parallel. In contrast, sieves have screens, holes, and meshes. With various aperture sizes, from coarse sieves (> 20mm) to micro-sieves (<0.05mm), these separate from solid substances emerging from the coarse garbage resulting from our civilization, to sand and mud particles from the flow of water. sewage water.

Of vital importance is mechanical preliminary cleaning in the treatment of domestic wastewater. Especially the fibers, especially the extremely tear-resistant textile fibers of wet wipes and fleece or non-woven material, which contain the waters represent a challenge. These fibers tend to become entangled and can clog and cause extensive damage to pumps and agitators.


Effluent Analysis

Environmental study and analysis of wastewater for industrial and sanitary use

Projects therefore begin with the study and advice in your plant, in addition to taking samples and laboratory analysis. This process is completed with laboratory-scale testing procedures or the use of an on-site pilot plant.

Our portfolio of services for wastewater analysis

In order to plan new wastewater treatment plants or to improve the performance of existing plants and to optimize them, it is necessary first of all to carry out a comprehensive analysis of the wastewater in question. Basic data such as the volume of wastewater per day of production, the temperature of the wastewater and the available surface area are essential for the overall design of a plant.

In addition, in the laboratory our experts analyze the composition of the wastewater and the substances it contains. With the help of an individual checklist, we together with you draw up a comprehensive table of special parameters, such as:

Analysis of important parameters of wastewater:

  • Chemical and biological oxygen demand (COD; BOD)
  • Polycyclic aromatic hydrocarbons (HAP)
  • Aromatic hydrocarbons (benzene, toluene, ethylbenzene and xylene (BTEX))
  • Concentration of N in ammonium (NH4 ‑ N)
  • NItrogen Nitrate (NO3‑N)
  • Phosphate compounds (PO4 ‑ P)
  • Chloor
  • Heavy metals

Physico-chemical and microbiological laboratory tests of your wastewater

Study of wastewater

The study of wastewater constitutes the basis for the compilation of the basic parameters and the comprehensive development of a wastewater treatment concept. Our portfolio of services begins with the study of wastewater on site or in our laboratory. In addition, we carry out investigations in accordance with the regulatory framework for self-control of wastewater treatment plants, the evaluation of the results of the analyzes, the preparation of technical reports and water and wastewater balances. On this basis we identify the potentials for the optimization of the processes.

Its advantages:

  • Direct laboratory connection with planning and development engineers
  • Consolidated database for the elaboration of a specific procedure concept for the client
  • Recognition of the potential for optimization
  • Cost savings through process optimization
  • Commissioning, sampling and optimization – all from a single source

Study of wastewater in our laboratory

After taking samples on site, we carry out basic studies of the effluent samples in our laboratory to determine their chemical composition, which allows us to develop a laboratory-scale process.

We can perform the following testing procedures for you:

  • Activated carbon tests
  • Ion exchange test
  • Making breaking curves
  • Carrying out biodegradability tests
  • Physical-chemical precipitation and flocculation tests
  • Assays – PAO (advanced oxidation process)

Study of wastewater through pilot plants

On the basis of the preceding laboratory tests and the results of the tests carried out, the project design can begin. Alternatively, it is also possible to design a pilot plant on a semi-industrial scale to carry out tests on site. Our test facilities are completely prefabricated and this enables rapid analysis, even of difficult-to-treat wastewater.



Process optimization with effluent treatment systems

The increase in the volume of wastewater, the modification in the concentration of effluents, the change of the substances contained in the wastewater and / or the modifications of the permits on the use of water make it necessary, many times, to adapt or complement existing technology.

Our wastewater treatment laboratory helps you optimize existing wastewater treatment systems. In this sense, for us the concept of “green chemistry” comes first. That means for us, increasing energy efficiency, reducing environmental pollution, applying analytical methods to control environmental pollution and supporting safer processes.

We evaluate the effectiveness of existing wastewater treatment systems to ensure effective treatment of partial flows or full treatment of direct or indirect input. Our portfolio of services includes, among others:

Biological wastewater treatment:

  • Organic load degradation
  • Nitrification (oxidation of ammonia or ammonium ions to nitrate)
  • Denitrification (reduction of nitrate to basic nitrogen)

Physical-chemical treatment of wastewater:

  • Precipitation / flocculation
  • Separation of unwanted substances
  • Activated carbon processing
  • POA-Advanced oxidation process





Heat Exchanger for Wastewater

E-Plate Heat Exchanger for Wastewater

Our E-Plate self-cleaning heat exchanger makes it possible to use the waste water, which comes out very hot from the process, to heat the cold water. This helps to optimize the temperatures of the water flows and also to reduce the energy consumption of the wastewater treatment.

High performance and energy efficient wastewater treatment through heat recovery

The use of our wastewater heat exchanger can be included from the beginning in the planning of your new wastewater treatment or installed later to optimize existing wastewater treatment plants.

Our engineers will advise you on how to make the entire plant more energy efficient, recovering the heat from the wastewater in the most efficient way possible.

Principle of operation of our heat exchanger E ‑ Plate

Our E ‑ Plate is a plate exchanger, more precisely a thermoplate-based exchanger, which is cleaned through an optimized system of brushes. Due to this, it is also suitable for highly polluted wastewater. It is made up of double-walled stainless steel plates, arranged in a ring shape, through which the cooling water is distributed and flows evenly. Waste water enters the heat exchanger from below, circulates up through the tank and runs off the top. Thus, cold water circulates inside the thermoplates and residual hot water circulates outside.

The continuous rotating brush system reduces dirt to a minimum and ensures a high flow rate. This increases the efficiency of the exchanger considerably. In addition, the rotating movement of the brushes makes the wastewater circulate in a spiral. This produces the effect of a countercurrent heat exchanger. This constructive principle allows installation at the outlet of existing wastewater treatment systems without the need for additional booster pumps. Even complex measurement and control technologies are not required.

Areas of application:

  • Paper industry
  • Biogas plants
  • Foundry workshops
  • Tempering workshops
  • Tintorerías
  • Industrial laundries
  • Food industry



Calculation of your energy saving potential by using the E-Plate heat exchanger

The infographic uses the example of a paper mill. The process water supplied at the start of production is too cold, 12 degrees Celsius, and needs to be heated. At the end of the process, the wastewater has a temperature of 55 degrees Celsius and is therefore too hot for the installed biological wastewater treatment system. The industrial water treatment plant would no longer operate at this temperature, as the microorganisms would die. Also, the official maximum temperature limit for discharge of wastewater is 30 degrees Celsius.

Not only paper mills have problems with the temperature of the water at the outlet. Biogas plant operators, foundries and tempering plants, dry cleaners, industrial laundries and even the food industry can all benefit from this type of system. With the heat exchanger, the plant can save 40% of the natural gas it previously consumed. This investment pays for itself in the first year.


Sewage Cooling

Cooling and temperature control of wastewater

The temperature of the water in the different stages of treatment plays a very important role in the effective treatment of wastewater flows. However, we must also focus on the temperature limit value or on issues related to energy recovery and bad odors.

Waste water temperature

In addition to analyzing wastewater flows and their composition, monitoring wastewater temperature is an essential element in planning and optimizing your wastewater treatment plant. Partial flows of water that are too cold are a problem, especially for anaerobic reactors, such as, for example,

UASB (Upstream Anaerobic Sludge Blanket), EGSB (Expanded Granular Sludge Blanket) or IC (Internal Circulation), since the metabolism of bacteria depends on a minimum temperature. If the water enters too hot in the biological treatment stage, the biomass can be damaged.

Commercial relevance of wastewater cooling

Wastewater treatment plant operators are interested not only in the efficiency of their cleaning but also in the commercial aspects of their wastewater flows. To protect adjacent waters and the living organisms contained in them, there are regulations that establish direct discharge temperatures. The competent water authorities generally determine the temperatures to be observed in each case. In the province of Buenos Aires, for example, this limit is 45 ºC. In the City of Lima it is 35ºC.

Another aspect to take into account is the appearance of bad odors due to heat flows in the pipeline. According to the external temperature, this phenomenon can be increased and be a discomfort for the inhabitants.

Cooling and energy recovery from wastewater

Cooling towers, falling film coolers, and tube and plate heat recovery units have proven to be useful solutions in process water cooling. However, in practice other systems prevail. A viable solution is to use spiral heat exchangers, but these come with a high maintenance cost. With self-cleaning systems such as the E-Plate rotary heat exchangers we have solved this problem.


Aeration of Wastewater

Automatic and Flexible System for Aeration of Wastewater

For the aerobic degradation of organic substances, ie oxidizable substances in wastewater, oxygen is required, which can be introduced into wastewater by compressed air. In addition to supplying the necessary oxygen, these wastewater aeration systems have the function of mixing the wastewater with the sludge or preventing accumulations in the tank.

Reasons for wastewater aeration

Carrying out aeration measures in your wastewater treatment plant can increase the safety and degradation capacity of the system. The purpose of aeration is to achieve a rapid transition of oxygen from the gaseous state to the liquid state. This can be achieved by increasing the oxygen concentration in the air mixture or by a mechanical solution, produced by the optimal bubble size. Depending on the task required.

If, for example, the aeration of the wastewater is also combined with a mixture of the biomass, submersible aerators (rotor type) are implemented as an active system. In other cases, it is preferable to use passive systems, such as perforated pipes, membranes or air ejectors. In the case of uncomplicated wastewater in MBBR with a high organic load, perforated pipes are used, which are characterized by a medium bubble aeration. If laboratory analyzes show that the wastewater has low lime content, it is preferable to install membrane aerators in the activation facilities.

Flexible aeration of wastewater with air ejectors

If the wastewater treatment consists of removing not only lime but also large solid substances and sludge and also allowing separate mixing and aeration operation, air ejectors are preferably used. An example of this can be the degradation of nitric nitrogen, for which a mixture of the wastewater without air intake is needed.

Air ejectors can be removed during continuous operation, allowing system maintenance without completely shutting down the wastewater treatment.

Its advantages:

  • Strong agitation and efficient aeration (separately controllable)
  • Special nozzle design prevents effective bottom sludge build-up and keeps solids floating – regardless of the amount of oxygen entering
  • There are no moving parts -> no need for special maintenance
  • Ideal for use in MBBR or activation facilities
  • Mobile solution allows maintenance during operation



Use of air ejectors in the paper industry

It is convenient, for example, to use air ejectors in calcareous wastewater, which is produced in the processing of waste paper. Lime deposits suffocate (clog) the membrane aerators at the bottom of the tank, which must compensate for the pressure loss with increasing power. The problem is solved by replacing the membranes with air ejectors. On the other hand, air jets add more oxygen to the water, whereby the reduction of COD in the same volume can be significantly increased.


Optimization of wastewater treatment plants

Optimization of existing wastewater treatment plants

Reduction in energy demand, in the use of inputs or a change in the quantity and concentration at the input: there are many reasons for optimizing existing treatment plants. We assists you in optimizing your wastewater treatment and creates an effluent treatment concept individually tailored to your needs.

7 steps to an optimized treatment facility

To optimize water treatment-dua-resi them is necessary to consider the correct hierarchy of objectives. This is the only way to modify the individual parameters or the treatment plant to meet all your specific requirements and wishes.

Our experts develop a specific concept for this, with which we will optimally adapt wastewater treatment together with you in 7 steps.

Development of an optimization of facilities

  1. Determination of objectives and inventory
  2. Preparation of substance balances
  3. Sketches for optimization
  4. Elaboration of the optimization concept
  5. Planning & engineering
  6. Implementación
  7. Evaluation of the results and final report

Optimization possibilities in wastewater treatment

There is no universal concept for optimizing an effluent treatment facility. Any solution must be developed for the particular project at the customer’s site. However, there are typical approaches that often make new construction completely unnecessary.

Energy cost savings through optimal aeration system

Oxygen is required for the aerobic degradation of organic and / or oxidizable substances contained in wastewater, which can be provided by means of aeration by injection of compressed air or aeration of the surfaces. Besides supplying the necessary oxygen, the systems for the aeration of effluents also have the task of mixing the waste water and the sludge or of preventing the formation of adhering deposits in the tank.

In the case of a biological treatment plant with the activated sludge process, the acquisition costs of a new fan represent only a small fraction of the total cost; however, decisive optimization potentials are being wasted here.


Is your wastewater treatment station still working with classic surface aerators? Using speed-regulated rotary piston compressors can significantly increase the energy efficiency of a biological wastewater treatment plant.

DAS Expert Environmental experts integrate the active or passive aeration system in your installation according to the specific objective.

Adequacy of temperature for optimization of wastewater cleaning

When optimizing the wastewater treatment plant, one must not forget the temperature limit values or the issues related to energy recovery and unpleasant odors.

Too cold partial flows are a problem for anaerobic reactors, since, for their metabolic processes, bacteria are subject to a minimum temperature. But if the water reaches the biological treatment phase too hot, the biomass can be damaged. In this sense, the odors generated by excessively hot effluents are another aspect to be considered.

Especially when the outside temperatures are high, this can cause a nuisance for the inhabitants due to bad smells and should be considered when deciding on an optimization.

In addition, the protection of adjacent waters and their living organisms play another important role in the optimization of facilities. There are public regulations of the competent authorities in the matter of water that determine the temperatures that must be respected for the direct discharge.

Wastewater heat exchanger: Energy and operation efficient wastewater treatment through heat recovery

The waste water that comes from the process that is too hot can be used to heat the cold water. This helps to optimize water flows and reduce the energy demand of wastewater treatment. Our E-Plate heat exchanger is a self-cleaning plate heat exchanger using an optimized brush system. Therefore, it is ideal for highly polluted wastewater.

The continuously rotating brush system reduces dirt to a minimum and also provides a high flow rate. This contributes to considerably increase the performance of the heat exchanger. The additional rotary motion of the brushes allows the waste water to circulate in a spiral, allowing the effect of a countercurrent heat exchanger to be achieved. Thanks to this constructive principle, it can be installed in sewage treatment plants without the need for additional pumps to increase the pressure and does not require expensive measurement and regulation technology.


Facility Construction of Industrial and Domestic Wastewater

Facility Construction of plants for the treatment of industrial and domestic wastewater

Once we have defined in the planning phase what your wastewater treatment facility will be through detailed analyzes, various authorization procedures and preliminary studies of the framework conditions at the site, we move on to the construction phase of the plant.

Project and portfolio management

As experts in the treatment of resi-les-dua waters , we handle the complete management of the project for the construction of its plant in wastewater treatment and peripheral equipment needed, for example; pumps, valves, metering and regulation technology. The most important thing for us is the satisfaction of our clients. Therefore, the key components are “Made in Germany” and meet the highest quality requirements.

The largely prefabricated wastewater treatment facility is delivered to the construction site and is very easy to assemble. Our experienced construction managers and assemblers organize all required accessory work, from the installation of pipes and electrical devices to the supply, installation and assembly of the aggregate units.

Software development and control cabinet construction

Together with our team located in Dresden we offer both the development of software for the control and automation programming of your plant, as well as the assembly of distribution cabinets and electrical panels. Our colleagues on site take care of installation, wiring, connection and function check.

Commissioning and process optimization of your wastewater treatment plant

Often, the commissioning of sewage cleaning facilities is done with the start of new productions. In this phase, our wastewater experts from the areas of chemistry, biology and plant construction accompany you to carry out an optimal commissioning, that is: the plant is adjusted exactly to your individual process parameters.

Project management for the construction of wastewater treatment facilities

It does not matter whether a wastewater treatment plant has to be built from scratch or modernized: we take care of the planning and turnkey construction of your individually designed and needs-oriented wastewater treatment plant. future. Our highly experienced project managers in wastewater treatment technology take care of all high-quality project development and on-time delivery.

We help you in the processing of authorization procedures, organize your work as a general contractor and coordinate the work until the final delivery of the project. For this, we always keep the budget in mind. You will save costs and time and can focus on your core business without worry.

In short, you get the following benefits:

  • Planning, supply and implementation from a single source
  • Optimal adaptation of individual components
  • The total solution with the best design down to the smallest detail
  • Fast, competent and hassle-free development
  • Cantidad mínima de interfaces
  • Import / customs clearance / billing from a single source
  • One contact person for warranty and service
  • Minimum cost and effort for spare parts management
  • Turnkey delivery
  • Technical service services (laboratory, maintenance)

Production and construction of your wastewater treatment plant

As a German company with headquarters in the city of Dresden and subsidiaries around the world, we can adapt our plant production flexibly to the planned location. Your advantage: you always get our German know-how, quality and a tailor-made solution. We have production centers in Germany and at our customers’ facilities around the world. We acquire the components of the plant, such as pumps, valves, measurement and regulation technology, from first-line suppliers, consolidated as quality leaders in recent years.

Due to the high quality requirements of our customers, we manufacture certain key plant components at our headquarters in the city of Dresden. The individual software for programming the control of your wastewater treatment plant is also developed here and the electrical cabinet is built. Thus, the largely prefabricated effluent treatment technology is delivered to the construction site and is very easy to assemble. Pre-assembly in container modules not only saves time, but also unnecessary export costs.

Installation of your wastewater treatment plant

Project managers and site managers are in charge of assisting the technical team in the installation of the wastewater treatment plant, including the organization of all required accessory work. This includes:

  • Dismantling of existing plants (if necessary)
  • Installation of stainless steel and / or plastic pipes
  • Electrical installation
  • Supply and installation of aggregate groups
  • Assembly equipment supply
  • Verification of the installed plant (density control, non-destructive test of welds)
  • Installation and connection of the electrical cabinet
  • Wiring of all components
  • Checking all electrical components

Commissioning and process optimization of your wastewater treatment plant

  • In many cases, a new wastewater treatment plant is put into operation in parallel with the start-up of a new production line. Our experienced process engineers from the areas of chemistry, biology and mechanical engineering accompany you in this process and coordinate the commissioning of the plant with the customer. After commissioning, the residual water is analyzed for the parameters allowed in our laboratory and, if necessary, the installation is optimized. Of course, the same is done with existing facilities.
  • You receive the complete technical documentation of the plant. Properly instruct their staff regarding the operation of the installation of wastewater treatment and will then attend the between-ga on any issue that you need.
  • Due to the very high quality of our effluent treatment plants, they are normally used for long years. During this time it may happen that the composition of the wastewater or the requirements regarding the limit values change. An optimization of the plant, that is to say: a new analysis of all the components and steps of the process, as well as the training of your personnel, can result in a cost reduction of around double digits