OVERVIEW OF WATER TREATMENT

What is water treatment?
Supply water is water after being treated and cleaned with modern technology at water plants. After that, water is transferred to transfer stations by pipeline system to supply to users.

Depending on different purposes of use such as water for drinking, water for domestic use or water for production, the quality of water supplied must meet standards according to different regulations. Because natural water sources such as surface water or groundwater do not meet these standards (due to the availability of each water source or current pollution impacts), we need to carry out the treatment process. Treatment of water supply to remove impurities and water-soluble substances, ensuring that the quality of treated water is satisfactory for each purpose of use.

Hoa Phat Eco Company is a reputable and leading water treatment contractor in Vietnam, with experience in design consultancy, construction and construction of many water treatment projects for domestic use, clean water treatment for domestic and foreign customers. industrial production plants such as:

• Water treatment for domestic use
• Water treatment for food and pharmaceutical production
• Ultra-clean water treatment for beer, wine and beverage production
• Water treatment for boilers

We understand the importance of water for life and production, so for each project, Hoa Phat Eco always provides superior solutions, with modern technology and the most professional service to bring to customers the best of both worlds. Customers with clean water of the best quality, ensuring health and safety standards for users as well as serving the production and business process.

From conventional to state-of-the-art technologies, our expertise encompasses the following treatment processes, and more:

• Reverse-osmosis desalination
• Coagulation and flocculation
• Clarification
• Flotation
• Multimedia filtration
• Activated carbon filtration
• Methane removal
• Biological filtration
• Arsenic removal
• Contaminants removal
• Denitrification
• Ultrafiltration
• UV disinfection
• Remineralization
• Softening
• Ozonation
• Mollusk removal

Our plants are fully automated and are controlled by our innovative Smart Operation suite, which enables real-time monitoring and response, and optimization of operating costs.

Sustainable Treatment Solutions for Drinking and Process Water

Whether you need drinking water for a community or process water for an industrial facility, Hoa Phat Eco has a sustainable solution for your operation. As well as large-scale water treatment plants, we specialize in decentralized water solutions that are modular, scalable, and quick to deploy.

Contact our experts to discuss your specific project details, and learn how our water treatment solutions can help you meet your goals.

In order for customers to have an overview and better understand about the field of water supply, we share some relevant information as below. If you are interested or have a need to invest in a water supply and clean water treatment system, do not hesitate to contact us for detailed and quick advice and quotation.

CLASSIFICATION OF WATER RESOURCES IN SUPPLY WATER TREATMENT

Classification by input water source:
– Ground water source: well water, …
– Surface water sources: rivers, lake, …

Classification by purpose of use:
– Water supply for drinking purposes (standard QCVN 01:2009/BYT)
– Water supply for domestic use (standard QCVN 02:2009/BYT)
– Water for production: water for food production, beer, wine, beverage, boiler water, …

 

METHODS OF SUPPLY WATER TREATMENT

The quality of the water source has an important meaning in the water treatment process and affects the selection of appropriate water treatment methods and technologies. Therefore, in the permissible conditions, it is necessary to choose the best quality water source to get high efficiency in the treatment process as well as save investment costs.
The basis for selecting water treatment technology is based on the following factors

• Quality of source water (raw water) before treatment
• The quality of water required (after treatment) depends on the purpose of the user
• Capacity of water plant
• Economic and technical conditions and investment scale

There are 3 basic water treatment methods:

• Mechanical method: Using equipment of Reservoir and pre-settlement, garbage screen, garbage screen, settling tank, filter tank.
• Chemical method: Use alum as a coagulant, use lime to alkalize the water, add chlorine to the water to disinfect.
• Physical methods: Using physical rays to disinfect water such as ultraviolet rays, ultrasonic waves. Electrolysis of seawater for desalination. Eliminate CO2 dissolved in water by aeration.

1. Water treatment by mechanical methods

To treat water by mechanical methods, we perform the following steps:

a. Reservoir creation and pre-settlement

b. Clearing suspended sediment

c. Set up barricades and garbage nets

Barriers and nets are placed at the water inlet to the collection work. Do the task of eliminating floating objects, floating objects in the water stream. To protect equipment and improve the cleaning efficiency of water treatment facilities. Floating objects and objects suspended in water can be as small as floating toothpicks. Or young tree branches when going through the pump into the works. Treatment may be pulverized or rotted, increasing the sediment content and color of the water.

d. Create a sand settling tank

In surface water sources with turbidity greater than or equal to 250 mg/l behind the screen. Inorganic suspended particles of small size. The density is greater than that of water, hard, capable of fast settling, which is retained in the sand settling tank. The task of the sand settling tank is to create good conditions for settling sand particles with size greater than or equal to 0.2 mm and density greater than or equal to 2.5. To eliminate wear on mechanical movements. And reduce the amount of heavy sediment that accumulates in the flocculation and settling tanks.

e. Create a settling tank

During the water treatment process, the settling tank is responsible for preliminary cleaning before putting the water into the filter tank. To complete the domestic making process. According to the flow direction, settling tanks are classified into: Horizontal clarifiers, vertical clarifiers, thin layer clarifiers and clear clarifiers with suspended sediment.

f. Filtration

Treatment of water supply, the filter is quite important, including the filter tank and filter equipment. Filtering speed is also a factor to consider.

The case of large capacity water treatment

In large capacity water treatment systems, there is no need to use high pressure filtration devices, but filter tanks with granular filter media. The filter media that can be used is quartz sand, coke, or crushed gravel, even brown coal or wood charcoal. The selection of filter media depends on the type of wastewater and local conditions. Filtration occurs by the following mechanisms:

– Screening to separate solid particles completely by mechanical principle

– Listen to gravity

– Holds solid particles by inertia

– Chemical adsorption

– Physical adsorption

– Adhesion process

– The process of settling cotton.

Filters with particulate layer can be classified into slow filters, fast filters, open filters and closed filters. The height of the filter media layer in the open filter device ranges from 1-2 m and in the closed filter from 0.5 – 1 m.

2. Water treatment by physicochemical methods

Water treatment by physicochemical methods includes the following steps:

a. Make airy

The essence of the aeration process is to dissolve oxygen from the air into the water to oxidize the divalent iron. Valence II manganese to valence III iron. IV valence manganese forms trivalent iron hydroxyl compounds. And the valence IV manganese hydroxyl Mn(OH)4 precipitates easily to be reduced from the water by sedimentation and filtration.

Ventilate to reduce CO2, H2S in water. Increases the pH of water, facilitates and accelerates the oxidation and hydrolysis of iron and manganese. Increased capacity of sedimentation and filtration works in iron and manganese removal processes. The aeration process increases the dissolved oxygen content of the water. Raise the redox potential of water to easily carry out the oxidation of organic substances in the process of deodorizing water and odors.

b. Preliminary chlorination

Pre-chlorination is the process of adding chlorine to the water before the clarifier and filter. Pre-chlorination has the effect of increasing the disinfection time when the water source is heavily contaminated with chlorine, oxidizing dissolved iron in the form of organic compounds, oxidizing dissolved manganese to form corresponding precipitates, oxidizing substances. organic to decolorize, prevent the growth of algae, moss, destroy the cells of microorganisms that produce viscous mucus on the surface of the filter tank.

c. Flocculation

In water sources, part of the particles usually exists in the form of finely dispersed colloidal particles. The size of the seeds usually ranges from 0.1 to 10 m. These particles neither float nor settle. And so it is relatively difficult to separate. Because of the small particle size, the surface area ratio. And their volume is so large that the surface chemistry becomes very important. As a rule, small particles in water tend to agglomerate due to the VanderWaals attraction between the particles.

This force can lead to adhesion between particles as soon as the distance between them is small enough due to collision. The collision occurs due to Brownian motion and due to disturbance action. However, in the case of colloidal dispersion. The particles remain dispersed by electrostatic repulsion because the surface of the particles carries an electrical charge. Can be negatively charged or positively charged by selective absorption of ions. In solution or ionization of active groups. The suspended state of colloidal particles is stabilized by electrostatic repulsion.

Therefore, to break the stability of colloidal particles, it is necessary to neutralize their surface charge. This process is called coagulation. The colloidal particles that have been neutralized can bond with other colloidal particles to form larger flocs. Heavier and subsided. This process is called cottoning.

d. Disinfect water

Water disinfection is a mandatory step in the treatment of domestic drinking water. In natural water contains a lot of microorganisms and sterilization. After mechanical feed water treatment processes, especially water after passing through the filter tank. Most of the germs were trapped. However, to completely destroy disease-causing germs. Water disinfection is required. Currently, there are many effective sterilization methods such as: Sterilization by strong oxidizing agents, physical rays, ultrasound, thermal methods, heavy metal ions, etc.

 

3. Water treatment by special methods

In addition to the above treatment methods, when the quality of the feed water is higher, the following methods are also used in the treatment of feed water:

– Deodorizes odors and tastes with air fresheners, strong oxidizing agents, activated carbon;

– Softening water by heat method, chemical method, ion exchange method;

– Desalination and desalination of water by ion exchange, electrolysis, membrane filtration, heat or distillation.

 

With the capacity, experience and understanding of water supply, HOA PHAT ECO brings solutions for consulting, design, construction and construction of a package of water treatment systems for domestic and industrial production with Reasonable investment costs, application of modern and safe technology, ensure the best quality of clean water for users and meet strict standards in production.