Sewage properties and treatment methods:

According to the process sequence and related technical requirements, provide practical guidance to help users understand and use.

Sewage is also referred to as waste water. It is water that is dirty and discarded, but the degree of pollution is different. Among them, the nature and concentration of pollutants are very random, and there is no standard to refer to. Only by gaining experience through practice, can we grasp the law of sewage properties and changes.

There are three types of modern treatment methods: 1. physical method, 2. chemical method and physical chemistry method, 3. biological method; the degree of treatment is divided into three levels: 1. filter suspended matter and particles, 2. decompose colloid and organic dissolved matter, 3. Remove residue more deeply.

Although the nature and conditions of various types of sewage are different, corresponding methods can be adopted, but the chemical physical method is closer to users with small sewage discharge: first, the colloid is chemically decomposed quickly, and the flocs are generated and dispersed in the water body, and then the adsorption physical changes between the flocs. Particles are formed and precipitated to separate the water body from pollutants.

adjusting:

The various components of pollutants, solid content, turbidity, chroma, PH value, etc. constitute the level of sewage concentration. High-concentration sewage lacks the necessary water as a space. Even if more chemicals are added, it cannot be treated, but it increases the substance. Saturation, so the test is performed before the treatment, and the high concentration and low concentration are adjusted first to make them meet the conditions of the treatment mechanism. This will not only have a good effect but also a low consumption of medicine.

Example 1: Equipped with a large sewage tank to collect the first concentrated sewage and the late fresh sewage together, and the water is naturally adjusted.

Example 2: There is only a small sewage tank, which is used repeatedly in order to save water, and even a small part of the remaining material (fluid) is discarded in the water. This concentration is too high and it is difficult to deal with; in addition, the ions of pollutants, due to their specific gravity, rise and fall in stages, forming a water body The upper, middle, and lower concentrations are uneven, and the processing container can be used for segmental adjustment to make it meet the processing conditions.

 1. PH value: After testing with test paper, add a little lime liquid, cement and industrial alkali as auxiliary agents to adjust the pH value between 7.2-8.5 (weak alkaline) according to the pH.

2. Concentration: first test the sewage. After the sewage is stirred, the agent will be dosed at a ratio of about 200 g/ton, and the effect will be observed after 2-5 minutes. If it can be treated with a little or a little agent, then continue; if the dosing is doubled, it is still not seen The effect proves that the lack of water has a high concentration, and the dosing should be stopped, and the low-concentration sewage should be equalized and adjusted until it can be treated. The water and concentration are suitable for treatment. At the same time, record the data for reference in future processing work.

Test process: 1T and 2T models are directly tested with a processor, and 3T models are tested with a small bucket. Both are filled with 50% of the volume of sewage. After stirring, add the agent. After mixing for 2-5 minutes, the pollutant colloid quickly generates electricity. The reaction mechanism of neutralization is that the colloid becomes thinned and dispersed into flocs (alum). In order to prevent long-term stirring from dispersing the agglomerated small particles, causing the colloid to re-stabilize in the water, the stirring should be stopped at this time and the initial precipitation should be entered. Let the flocculated particles gradually cultivate and firm up, and stir again after 5-10 minutes. The thicker and larger particles become cloud-like adsorption bridges, such as catching nets and sweeping to absorb small particles scattered in the water, and the water is immediately clear and transparent. The mixing process is more complete, and then the sludge is separated from the water by standing for precipitation.

The appropriate concentration is based on the dosage of 160-200 g/ton.

The first time I understand sewage treatment technology, I don’t know that adjustment is the key. I think it can be solved by just adding more medicine. The treatment effect is good, and the time difference is good. Even more and more medicines are used. In fact, other conditions and conditions are not adjusted in place.

The edge of the sewage pool should be heightened and barriers should be installed, and a roof should be set up to prevent rainwater from entering. The pool mouth should be kept open. The sediment at the bottom of the pool and the retention area at the four corners should be promoted and renewed to prevent mutation and odor. The sewage pump is equipped with a filter device.

Flocculation:

After the sewage is adjusted by PH value, concentration, etc., start stirring to transfer the sewage, and evenly put in the chemicals. Refer to the process regulations of each model for details.

If the flocs are small and the water body is corroded, it proves that the dosage is too small, add the agent in time and extend the mixing time slightly until the treatment is completed.

precipitation:

The sedimentation process is also very important. Don't rush to achieve results and reduce the treatment results. In order to make the sedimented pollutants better out of the water body, sedimentation is more than 15 minutes or longer.

If it is not easy to settle or the speed is too slow, adding less cement to increase the specific gravity of flocculated particles will be effective.

emission:

"Integrated Wastewater Discharge Standard" GB8978-1996 After 1998.1.1

Sewage — Refers to the general term for water discharged in production and living activities.

Main pollutant discharge allowed: (mg/L)

Note: Class I-key protected water sources and tourist attractions, Class II-cities and densely populated areas, Class III-towns and rural areas.

Water sample collection: Pack about 250ml in a clean transparent bottle, and label the sampling unit, time, sewage type, etc., and send it to the environmental monitoring department for analysis.

Note that the freshly treated clean water should not be discharged directly. It should be discharged into the clean pool for observation to stabilize the water quality and prevent accidents from being irrecoverable; if necessary, add biochemical and oxidation facilities for subsequent treatment and discharge to the standard.

Reuse:

Although the treated good water quality meets the requirements for reuse, it can be used for washing utensils, environmental sanitation, etc., as well as other aspects such as watering flowers and fish farming. It saves energy and reduces emissions, and also saves treatment costs.

Water reuse rate:

General water properties

80% used without requirement, 60% after filtering or advanced treatment

The repeated reuse of clean (medium) water is called "zero" discharge, which does not mean no discharge, but less discharge. Due to the lack of sterilization and disinfection, the clean water that has been reused for many times cannot be fully circulated when stored in the water tank for a long time. There is a breeding space for various bacteria, and the water quality changes and smells, and even affects the entire system. It must be replaced regularly. Fully clean up to keep the entire system in a fresh and circulating state, especially in summer when the temperature is high, or before it is not used for several days, all clean water must be drained. (Add the environmentally friendly fungicide and food grade 84 disinfectant in proportion)

filter:

Part of the sludge should be temporarily retained in the processor to serve as a return flow, which is conducive to the next treatment and thorough digestion, but pay attention to promoting circulation and replacement to prevent layer formation. The sludge should be removed and rinsed if it is not running for a long time.

Due to the combination of the special effect of the medicament and the colloidal components in the pollutants, the sludge particles have strong coagulability and are easy to filter and dry. The ordinary bag filter can be used, and the operation is very simple. In order to prevent the leakage of fine particles, the filter cloth density is selected in 160-180 mesh, pay attention to the heavy sludge with water, and there should be a leaky bracket protector outside the bag to prevent the cloth filter bag from cracking.

If the sludge filtration work is not enough, you can adopt the traditional multi-pool alternating sand filter to be more convenient and economical: the bottom of the pool is first laid with 10 cm thick stones to drain, and two layers of filter cloth are laid on the stones, and there should be no gaps around them. Spread the filter sand with a thickness of 10 cm. Do not approach the filter cloth each time to prevent the filter sand from being washed away. (3T type recommended to increase the screw stacking machine)

Sludge treatment:

Strictly control the treatment of sludge to prevent re-pollution. It is a required part of the sewage treatment process. There is very little sludge with a small discharge volume. In reality, it is impossible to complete the final treatment by itself. The sludge is naturally dried into a solid state and used in woven bags. Install it as solid waste and transport it with qualified departments to realize landfill or incineration treatment.