Characteristics of wastewater and methods of analyzing some basic criteria

1. Factors affecting wastewater quality

Wastewater quality is influenced by many different factors, including both natural and artificial factors. Below are some important factors that affect wastewater quality:

- Natural properties:

Origin of wastewater: Wastewater can come from different sources such as residential, industrial, agricultural, and herbal. The nature of the source will affect the pollution content in wastewater.

Chemical composition of wastewater: Wastewater may contain pollutants such as organic matter, nitrogen, phosphorus, heavy metals and other chemical compounds. The rate and type of these pollutants will affect wastewater quality.

- Artificial activities:

Technology and treatment process: The wastewater treatment method used will directly affect the quality of treated wastewater.

Treatment agents: Using chemicals, microorganisms or other treatment materials will also affect the quality of treated wastewater.

- Environmental conditions:

Temperature: Temperature affects the rate of chemical and biological reactions in wastewater. Hot wastewater often stimulates faster metabolism.

pH: The pH of wastewater can affect the ability of microorganisms and chemical processes to metabolize pollutants.

- Initial pollution level:

Initial level of pollution in wastewater: The initial level of pollution will affect the ability and efficiency of the wastewater treatment process.

- Management and maintenance:

Wastewater treatment system management: The process of managing and maintaining the wastewater treatment system will affect the treatment capacity and performance of the system.

- Impact from the surrounding environment:

Weather and seasons: Weather and seasons can affect the temperature, water flow and habitat, affecting natural and artificial wastewater treatment processes.

Thus, wastewater quality is the result of a complex interaction between many different factors, from natural to artificial. To treat wastewater effectively, it is necessary to consider and adjust these factors in the best way.

2. Basic wastewater criteria

- BOD (Biological Oxygen Demand): Measurements of the amount of oxygen needed for the biological decomposition

- COD (Chemical Oxygen Demand): Measurements of the amount of oxygen needed for the chemical decomposition

- Coliform bacteria concentration: Assessment of the level of contamination by microorganisms

- Heavy metal concentration: Measurements of the amount of heavy metals such as lead, mercury, cadmium

3. Method of analyzing wastewater criteria

3.1 Analysis of the chemical indicators in wastewater

The chemical analysis of wastewater is the process of identifying and measuring the chemical components in a wastewater sample. This helps to evaluate the wastewater quality, to determine pollution levels and to ensure that the wastewater meets specific safety and environmental standards.

Below are some popular chemical analysis methods for wastewater indicators:

Spectroscopic analysis: Use of a spectral analyser to identify the chemical substances based on light absorption and emission. Common methods include UV-Vis spectroscopic analysis (from ultraviolet to near ultraviolet) and atomic absorption spectroscopy (AAS) analysis.

Chromatography analysis: This method uses techniques to separate chemical compounds in a sample based on interactions between substances and a stationary phase. Chromatographic analysis methods include high performance liquid chromatography (HPLC), gas chromatography (GC), and ion exchange chromatography.

Electrochemical analysis: Method to measure the electrochemical properties of chemicals in wastewater. For example, conductivity, pH and redox potential (ORP) to evaluate the chemical and electrochemical properties of wastewater.

Natural particle spectroscopy analysis (ICP-MS, ICP-OES): Use of natural particle spectroscopy to quantify chemical elements in wastewater samples. This method is very effective in determining heavy metals and trace elements.

Titration analysis: Use of the titration method to determine the concentration of a chemical in a wastewater sample by adding an amount of agent solution until the reaction is completed.

Adsorption analysis: Use of adsorbent compounds in order to remove specific substances from wastewater and then measurement of the concentration of adsorbed substances using other analytical methods.

The above methods are often used to determine specific chemical indicators in wastewater such as BOD (biological oxidation demand), COD (chemical oxidation demand), concentration of heavy metals, and organic substances. muscle, nutrients, and many other indicators. Depending on the purpose and properties of the wastewater, different analytical methods can be applied to evaluate wastewater quality.

3.2 Analysis of wastewater biological indicators

Biological analysis of wastewater indicators is the process of evaluating factors related to the life and activity of living systems in wastewater, such as bacteria, microorganisms and other living structures. This is a way to measure the impact of wastewater on the living environment.

Below are some popular biological analysis methods for wastewater indicators:

BOD (Biological Oxidation Demand): Measurement of the amount of oxygen needed for bacteria and microorganisms to metabolize organic substances in wastewater in a certain period. BOD is often used to evaluate the level of organic pollution and the conversion capacity of wastewater.

COD (Chemical Oxidation Demand): Measurement of the amount of oxygen required to chemically oxidize all organic compounds in wastewater into oxidation products. COD is often used to assess the level of organic pollution and can provide results more quickly than BOD.

Bacterial growth: Assessment of the ability of bacteria to grow in wastewater by measuring bacterial growth over time.

Microbial analysis: Assessment of the presence and diversity of microorganisms in wastewater through determining the type and quantity of bacteria, algae and other living systems.

Analytical biology of aquatic grass samples: Measurement of pollutant removal efficiency using aquatic grass to metabolize substances in wastewater.

Biological analysis of other indicators: Some other biological indicators such as food circle coefficient, methane metabolism, and other biological indicators can be used to assess the environmental status of wastewater.

These methods help to assess the impact of wastewater on the living environment and the resistance of living systems in wastewater. Biological analyses of wastewater indicators are often combined with chemical analyses to provide a comprehensive view of wastewater quality and its impact on the environment.

3.3 Analysis of heavy metal indicators in wastewater

The analysis of heavy metals in wastewater consists of determining and measuring the concentration of heavy metals in wastewater samples. Heavy metals such as mercury, cadmium, lead, zinc, nickel, and others can harm human health and pollute the environment if they come from wastewater.

Below are some methods to analyse the heavy metal concentration in wastewater:

Natural particle spectroscopy analysis (ICP-MS, ICP-OES ): Use of natural particle spectroscopy method to quantify heavy metals in wastewater samples. This method allows for very small and extremely precise measurements.

AAS Analysis (Atomic Absorption Analysis): Use of the atomic absorption method to quantify heavy metals by measuring the amount of light absorbed of the different wavelengths.

Voltammetry analysis (Potentiometric analysis): Use of a potentiometric variation measurement method to quantify heavy metals based on the interaction between metal ions and electrodes.

XRF analysis : XRF analysis allows the measurements of the emission of X-rays after exposure to X-rays.

Automatic analysis : Some automation equipment can be used to analyse heavy metals in wastewater through the above methods automatically and effectively.

These methods often require the use of specialized equipment and machinery, along with careful sample preparation steps. Analysing heavy metal indicators in wastewater is very important to ensure that wastewater does not contain too high concentrations of heavy metals that are harmful to the environment and human health.

Analyzing wastewater criteria provides information about the composition and condition of wastewater, thereby helping to manage and adjust treatment processes in wastewater treatment systems to ensure that wastewater meets some pre-requisite standards when released into the environment. This can help to determine past contamination trends and treatment performance.