Nước thải sinh hoạt là gì ? Đặc điểm và tính chất

What is your birth country?

It is not difficult to come across domestic wastewater in life. This water source not only pollutes the environment but also affects human health.

So what is domestic wastewater? Where did it originate from? And how to treat domestic wastewater? Now diennuockhanhtrung.com will decipher it for you, keep an eye on it!

Bạn Đang Xem: Nước thải sinh hoạt là gì ? Đặc điểm và tính chất

What is domestic wastewater?

This is a kind of cloudy gray liquid with a bad smell formed from human activities such as washing dishes, cleaning the kitchen, cooking, washing clothes…

What is your birth country?

Origin of domestic wastewater

Domestic wastewater originates from human activities in apartment buildings, hospitals, schools, factories, factories, offices, construction sites, etc. Here are some of the most common areas. that you should pay attention to:

Wastewater from toilets, septic tanks, public toilets

This type of domestic wastewater contains thousands of contaminants. These are organic substances such as urine, feces and some viruses that cause disease.

With the main ingredients are BOD5, COD, Nitrogen and Phosphorus. Above all, when the amount of Nitrogen and Phosphorus is not removed, the wastewater will be eutrophicated.

beautiful country

Most toilets and public toilets… have septic tanks, which are responsible for waste collection and treatment. But if used for a long time, the microorganisms that decompose organic matter will be destroyed or the amount of wastewater is too large, causing the toilet to have a bad smell.

Waste water from the washing area

In fact, the wastewater from the bathroom will have a low level of pollution. Because the contaminant components in the water are not many. Therefore, this wastewater is usually put directly in for treatment in the following steps.

Wastewater from the kitchen area

The kitchen is a cooking area, so the fat content is quite high, along with food crumbs and organic waste. This grease does not seriously affect the drainage problem, but will cause the drain pipe to clog.

Thailand is very rare

Therefore, the wastewater in the kitchen area will be put into preliminary treatment before taking the next steps. If the grease is too thick, clogs the pipe, and gives off an odor, the best way is to use a microbial product.

Characteristics of domestic wastewater

What are the properties of domestic wastewater? This is probably the question of many people. Here are the common properties that you need to know.

Physical properties

– Temperature: Depends on weather, climate or living environment

– Color: This water will normally be brown or black.

Turbidity: Due to suspended particles and decomposing organic matter. The more turbid the water, the more dirty it is.

– Taste: Depending on the amount and characteristics of the pollutant, the smell of wastewater will be different.

Chemical properties

– pH: Plays an essential role in the treatment process, allowing you to choose the right solution or adjust the amount of chemicals during water treatment.

– Index DO: Oxygen plays a vital role in maintaining the life of aquatic microorganisms. In a severely polluted environment, oxygen will be used a lot for biochemical processes, causing an alarming level of oxygen deficiency.

– BOD index: This is the oxygen needed to carry out the oxidation of organic matter by aerobic and saprophytic microorganisms. Hence, this is called biological oxidation.

– COD index: Is the amount of oxygen needed to carry out oxidation, organic chemicals in water become CO2 and H2O thanks to strong oxidation.

Biological ingredients

This ingredient will include a collection of microorganisms such as algae, yeast, bacteria …

Regulations on domestic wastewater treatment

It is essential to understand the regulations on domestic wastewater treatment. Therefore, we will reveal to you the latest regulations on domestic wastewater treatment today:

What is COD content in domestic wastewater?

COD is an acronym in English (Chemical Oxygen Demand), which denotes chemical oxygen demand. In which, COD content indicates the amount of oxygen needed to oxidize the chemical compound.

In addition, COD content also represents the presence of compounds present in domestic wastewater. When the concentration is higher, it means that the wastewater source has been seriously polluted.

What is wastewater COD?

Xem Thêm : Cách đấu công tắc và lắp hộp số quạt trần Chuẩn Xác Chi Tiết 100%

COD is a compound suspended in water, but we will not see it with the naked eye. In fact, it is very dangerous, can damage the eyes, affect the respiratory tract, digestive tract and skin …

country code

Harmful effects of COD content

– Adverse effects on human health

– The air will be polluted

– Water and soil environment are also polluted

Methods to reduce wastewater COD

With the development of science, there are thousands of ways to reduce the harmful effects of COD in water, such as: Chemistry, biology, physics, physical chemistry… In which, the use of MET water treatment technology is Recently appreciated solution.

Pollution indicator Load factor (gram/ng/day)
Suspended solids 70 – 145
Ammonium (N – NH4) 2.4 – 4.8
BOD5 of water 45 – 54
Nitrogen 6 – 12
Phosphorus synthesis 0.8 – 4
COD 72 – 102
Grease 10 – 30

All waste today uses this technology, because it operates completely automatically and transparently. Therefore, when treating wastewater, there is no need to add or remove any substances.

Quality of domestic wastewater

Domestic wastewater contains many harmful pollutants. Therefore, it is necessary to handle it quickly to ensure hygiene and safety for people.

Regulations of the National Technical Regulation on domestic wastewater QCVN14: 2008/BTNMT of the Minister of Natural Resources and Environment: After being treated, wastewater must have pollution parameters within the allowable limit.

Standards for domestic wastewater treatment

When treating wastewater, there will be separate domestic wastewater treatment standards. For units that are required to comply with these regulations are:

– Restaurant Hotel

– Industrial parks, enterprises

– Condominiums, apartments

– Hospital

Thai food and drink

Maximum allowable value in contaminants

The specific standards are shown in the following table:

STT Standard parameters Unit OLD Value
first 5 to 9 5 to 9
2 BOD5 (20 0C) mg/l 30 50
3 Standard total suspended solids mg/l 50 100
4 Standard for dissolved solids mg/l 500 1000
5 Standard Sulfur H2S mg/l first 4
6 Ammonium (in N) mg/l 5 ten
7 Nitrate NO3 mg/l 30 50
8 Vegetable oils and fats mg/l ten 20
9 Total surfactants mg/l 5 ten
ten Phosphate (PO4) in P mg/l 6 ten
11 Total Coliform MPN/100ml 3000 5000

Standard coefficient K

K is the coefficient calculated for the size and type of facilities:

Base type Size and area used The value of the coefficient K
Hotels and motels From 50 3 star hotels or more first
Less than 50 hotels 1.2
Agencies, offices, schools and research facilities Greater than or equal to 10,000 m2 1.0 1.0
Under 10,000 m2 1.2
Supermarket, grocery Greater than or equal to 5000 m2 1.0
Market Greater than or equal to 1,500 m2 1.0
Under 1,500 m2 1.2
Restaurant Greater than or equal to 500m2 1.0
Under 500 m2 1.2
Production facilities and armed forces From 500 people or more 1.0
Under 500 people 1.2
Apartment buildings, residential areas From 50 apartments or more 1.0
Less than 50 apartments 1.2

4 methods of domestic wastewater treatment

Here are 4 commonly used domestic wastewater treatment methods:

Mechanical processing method

This method is a premise to support biological and chemical methods to go smoothly. It works based on the process of filtering, settling and separating solids present in water by:

Use a mesh screen to remove debris and obstructions along the water flow. The settling tank will be responsible for completely removing suspended substances. Oil separator tank, separates solids with a volume smaller than water, such as grease…

do you study abroad?

Not only that, it can adjust the flow and the concentration of the water source is stable. Especially maintain and improve the later processing stages to be better.

Biological treatment of wastewater

This method utilizes the soluble and insoluble properties of organic compounds found in water. It basically consists of 2 processes which are:

Anaerobic: Use anaerobic organisms and place them in a place where there is no oxygen content.

– Aerobic: It is required to group aerobic organisms and leave it in an environment containing lots of oxygen.

birthday celebration

Xem Thêm : So Sánh giàn giáo khung xây dựng sơn và kẽm

When working, organic substances have wastewater, depending on the organism, it is a biochemical oxidation process. At this time, the organic matter will dissolve, make the glue disperse and move into the inner cells of the organism, specifically there will be 3 stages:

– Bringing pollutants in liquid form to the surface of biological cells

– It will diffuse in the membrane cell by cell differentiation

The biological method of converting the substances of reproductive cells into energy for the synthesis of other cells.

Chemical treatment of wastewater

Chemical treatment methods used in wastewater treatment systems are: Neutralization, redox and precipitation or decomposition of toxic substances.

– Neutralization: This method uses many different ways. It can be mixing wastewater with alkaline or acid, adding chemical agents, purifying acidic water with filter media and tolerating acid gas with alkali or absorbing ammonia with acidic water.

– Oxidation and reduction: Cleaning domestic wastewater with chlorine in gaseous and liquefied form, potassium permanganate, potassium bichromate, air oxygen, ozone, calcium chlorate…

– Compounding toxic substances: Usually toxic substances will be present in wastewater, but in the process of oxidation, toxic substances will be converted into less toxic substances and separated from the wastewater. A large amount of chemical agent will be consumed from here.

happy birthday flowers (1)

Wastewater treatment by physicochemical methods

The physicochemical methods applied are: Coagulation, coagulation, absorption, ion exchange, ultrafiltration, etc. The treatment by this method will be independent or can be combined with chemical methods. , biology, mechanics.

Treatment of domestic wastewater by physical and chemical processes is the essence of physico-chemical methods. In order to add to the wastewater, the reactants directly affect the dirt and create residues or dissolved substances, which are completely non-toxic.

su-ly-nuoc-thai-bang-ly hoc

Domestic wastewater treatment process

The treatment of domestic wastewater requires clear design drawings. To ensure the highest quality processing.

Make a diagram of wastewater treatment

because of the balance of the country

Drawing of domestic wastewater treatment tank

Wastewater treatment tank is the place to exchange and treat wastewater. It consists of 7 parts as follows: Receiving tank > Conditioning tank > Aerobic tank > Anoxic tank > Settling tank > sterilization tank > Sludge tank.

Have you visited Thailand?

Domestic wastewater treatment process

– Waste water will collect into the pipeline system through the garbage separation system to keep dry components and large residues.

– After separating the garbage, the wastewater will go through the collection tank, at this time the grease will be prevented.

– The water in the wastewater collection tank will be pumped to the conditioning tank, the air blower will supply air, then mix it with the entire tank volume and the wastewater will be pumped to the aerobic biological cell.

– On aerobic biological cells, aerobic microorganisms use dissolved oxygen, converting organic matter into biomass, water and CO2. The microorganisms congregate in colonies, in the form of activated flocs.

the birthing process of the country of birth

– Dissolved oxygen is supplied in the blower by the air distribution pipe. This source of dissolved oxygen will ensure a smooth biological oxidation and nitrification process. The water will be cleaned, the microbial biomass will increase.

– The wastewater continues to pass through the settling tank to separate the microbial biomass. The sludge will settle at the bottom of the tank, the water in the water collection trough system will flow to the disinfection cell. At this time, disinfectant chemicals are pumped directly to the tank to destroy harmful microorganisms.

– Waste water is pumped into the filter equipment including: Quartz sand and support gravel. Then the compound that creates the clarity of the wastewater is removed. The treated water will be supplied to the environment, the sludge is led to the sludge decomposition tank.

Above is all information about domestic wastewater. Hope you have understood what is domestic wastewater? And choose the appropriate domestic wastewater treatment method. Thank you for paying attention to the article!

Nguồn: https://datmientrung247.com
Danh mục: Điện

Related Articles

Trả lời

Email của bạn sẽ không được hiển thị công khai.

Back to top button