How does an industrial wastewater treatment plant work?

Purifying contaminated water from industrial processes efficiently and sustainably It is essential to protect people's health and the well-being of ecosystems.

Investing resources in the treatment of industrial wastewater is also highly beneficial for companies: it allows them comply with environmental regulations, improve its corporate reputation, reduce your operating costs and to promote a circular and resilient economy. 

At SITRA we are providers of comprehensive water management solutions and services, and we want to explain to you what an industrial wastewater treatment plant is and how it works.

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How a wastewater treatment plant works: preparation, phases and discharge 

Water from industrial processes may contain physical contaminants (garbage and sediment), chemical (heavy metals, excessive nutrients, and industrial chemicals) and biological (bacteria, viruses or parasites).

Wastewater treatment plants are facilities where these components are removed or reduced so that the water can be reused or returned to nature without risks. 

The water cleaning process is carried out in three phases: 

1. Disposal of larger waste items.
2. Elimination of organic matter and microorganisms.
3. Elimination of nutrients and chemicals.

To truly understand how an industrial wastewater treatment plant works, we need to examine each of these phases. but also in its preceding and subsequent processes: 

• Preparation. It consists of Remove coarse solid waste, using grids or sieves, to avoid blockages in the water treatment plant. 
• First phase This first treatment is based on the sedimentation: suspended particles in the water settle to the bottom of the tank due to gravity, allowing them to be easily removed. 
• Second phase. The second phase of water treatment consists of decompose organic matter remains using bacteria and fungi to convert them into carbon dioxide, water, and other byproducts. 

To speed up the biological process, the following are used: activated sludge, biological filters or stabilization ponds.

• Third phase. It is the "most advanced stage" of the Industrial wastewater treatment through chemical methods and products which include filtration, disinfection with chlorine or ultraviolet light, or adsorption with activated carbon. 

Nitrogen and phosphorus can also be applied to prevent algae growth (eutrophication). 

• Sludge treatment. In industrial wastewater treatment plants, The sludge generated by sedimentation and decomposition of organic matter is treated separately. to reduce their volume before final disposal or reuse. To achieve this, they undergo processes of thickening, anaerobic digestion and dehydration.
• Reuse and/or discharge of water. Once treated and cleaned, the water from factories and industries It can be reused in other industrial processes and in agricultural irrigation systems.

It can also be used to recharge aquifers or be discharged into natural watercourses (rivers, lakes, reservoirs, etc.) provided that the quality standards set out in local, regional, national and/or international legislation are met. 

Types of wastewater treatment plants for wastewater from industrial activity  

One of the things to understand before learning how an industrial wastewater treatment plant works is that There are several systems for cleaning contaminated water from industry. 

They all include basic systems, such as manual coarse screens to prevent blockages in later stages of treatment, or filters to remove biological contaminants.

However, depending on the main method they use to treat the water, Wastewater treatment plants can be classified into four groups: 

• Oxidation wastewater treatment plants with lamellar filters. They are effective for separate fats and perform an initial roughing of the waterIts main components are: biological reactor, settling tank and lamellar filter.
• Physical-chemical water treatment plants. They remove contaminants from water using coagulation, flocculation, and filtration.
• Biological wastewater treatment plants. They break down organic matter of industrial wastewater using microorganisms.
• Mixed wastewater treatment plants. They combine physical-chemical and biological processes to achieve a more complete and efficient water purification.

How to choose a wastewater treatment plant for industrial wastewater? 

The first step is to assess the needs of each company, taking into account: 

1. El volume of wastewater generated. 
2. El types of pollutants that go into the water (suspended solids, metals, organic compounds, etc.). These pollutants are usually related to the type of industry or production sector. 

For example, in the food industryBiological treatment plants allow the treatment of water with high fat and protein content.

In the chemical plantsPhysical-chemical wastewater treatment plants facilitate the removal of toxic compounds and heavy metals, while in the textile industryMixed wastewater treatment systems cover the dual function of removing waste containing dyes (e.g., fabrics) and chemicals. 

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Other aspects that may influence the choice of a wastewater treatment plant are: 

• Compliance with Law 5/2002 related to wastewater from industry. This law specifies the maximum limits for each pollutant, the different discharge measurement systems, and the technical requirements that these types of treatment facilities must meet.
• Compliance with the Directive 91/271/EEC. This European standard establishes the quality standards for water once it has been treated for reuse in urban environments.
• That the installation be evaluated and Obtain the relevant permits and authorizations for the discharge of industrial wastewater. 

At SITRA we are experts in water treatment: discover how we can help you 

In SITRA We offer comprehensive and innovative solutions for the efficient and sustainable management of water derived from industrial processes, from the generation of renewable gases and the production of biofertilizers. 

Our services include water treatment plant upgrades, design and Construction of wastewater treatment plants, development of reuse solutions and maintenance of facilities to ensure its optimal and efficient operation.  

Make us your trusted partner for your wastewater treatment. 

➡️ Contact us now! 

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