Efficient hydrolysis and acidification technology
The high-efficiency hydrolysis and acidification technology uses anaerobic treatment to diffuse the impurities in the water, and then slowly separate them to react with substances. The processing process can be summarized as component diffusion, reaction, substance precipitation, coagulation, and separation. In all processes, the reaction is the most important process, and only in the process of material contacting each other can real reactions occur, and only then can mutual interaction occur. mass transfer. In the following, the technical content will be explained in terms of the type of reaction and the type of mass transfer diffusion.
1.1 Types of reactions
The reaction process mostly occurs in the reactor, which can be divided into two categories according to the reactions that take place, one is homogeneous and the other is heterogeneous.
The prominent feature of the former is that a scale is selected from the reactor, and the unit of this scale is smaller than the overall unit, and after the reaction is over, there will be no big difference between the objects before and after the reaction in the micro-members, and the molecular scale is kept uniform, so , after the homogeneous reaction occurs, the heat will not be transferred to the outside because of the difference of micro-elements, and the heat only comes from the heat generated by the macroscopic movement of the material.
The latter is a reaction between multiple phases, such as the reaction of two or more substances. Its specific feature is that after extracting any scale from the reactor, although the scale is smaller than the reactor, its interior still remains. There are a large number of microelements, and each microelement has its own composition, and temperature, and is different from the other. Therefore, after the reaction occurs, the macroscopic motion of the object and the microelement scale can transfer heat to the outside.
1.2 Types of Mass Transfer Diffusion
Based on the description of the above reaction types and the consideration of different reaction factors, the types of diffusion can be divided into the following types: molecular diffusion, thermal diffusion, pressure diffusion, forced convection-diffusion, natural convection-diffusion, interphase mass transfer, etc.
Among them, the first three types of diffusion, molecular diffusion is one of the more typical diffusion methods, which occurs with the increase of pollutant concentration in wastewater.
As the mass transfer proceeds, the last three diffusion modes occur, depending on the movement of the fluid. Among all the modes of fluid flow, turbulence will have a greater impact on mass transfer.
In addition, the formation of forced convection flow pattern is affected by and generated by an external force, which mainly comes from fans, mixers, etc., while natural convection-diffusion is formed with the change of fluid buoyancy, under the action of different gravity Under the temperature, the difference in temperature change is formed, and the fluid is also affected by it, forming a density difference, and on this basis, a buoyancy effect is formed. Finally, interphase mass transfer is the transfer of substances at the interface, and the reason for this transfer mode is the imbalance between phases.
Effectiveness and mechanism of efficient hydrolysis and acidification wastewater treatment technology
When using high-efficiency hydrolysis and acidification technology to treat wastewater, it is necessary to use corresponding devices to complete the entire treatment process.
The device includes a high-level water tank, a temperature meter, a reactor, etc., among which, the design of the reactor is relatively independent. When wastewater enters and flows out of the device, it will easily form turbulent flow due to the flow between multiple plates, and the process of diffusion of matter.
Based on this, the author summarizes the efficacy and mechanism of this technology by consulting relevant materials and referring to relevant experiments.
2.1 Technical efficacy
The author refers to the treatment of industrial wastewater and expounds on the technical effect. Industrial wastewater contains a large number of microorganisms, organic matter, phosphorus, etc. In the reference case, the experimenters came to the following conclusions after treatment according to the temperature requirements of microorganisms and other substances and the different reactions that occurred.
The amount of dissolved oxygen: The amount of microorganisms in the reaction is directly related to the change in the amount of dissolved oxygen. Technicians have been monitoring changes in dissolved oxygen since the reaction unit was started up in this case.
It is concluded that at the interface between liquid and gas because the amount of dissolved oxygen increases greatly if there is oxygen consumption, it can also be quickly replenished, but as the depth of dissolved oxygen deeper into the water increases, dissolved oxygen disappears after a certain depth.
From another perspective, technicians can find the best areas for dissolved oxygen in the water, speeding up the treatment of different pollutants in the wastewater.
Effective removal ability: Because most of the wastewater is acidic, Na2CO3 is usually used to adjust the wastewater to change it from acidic to alkaline, thereby enhancing the buffering capacity.
After adjustment, the pH value of the wastewater all exceeded 4.8. Another point to note is that the number of microorganisms will change with the pH value. Therefore, when the pH value is always maintained at 4.8, the organic matter in the wastewater will speed up the reaction and diffusion, and the amount of organic matter will be significantly reduced. The technology’s decontamination ability.
Removal of total phosphorus: The total phosphorus in wastewater treated with this technology is eliminated by microbial assimilation. Therefore, the removal rate of phosphorus depends on the number of microorganisms produced. In the process of treating wastewater by hydrolytic acidification technology, the number of microorganisms will be appropriately increased according to this characteristic. After the number of these microorganisms is integrated with the microorganisms in the wastewater, it can efficiently react with phosphorus to reduce the amount of phosphorus.
Improve biodegradability: The biggest effect of this technology is to improve biodegradability. It means that in the process of wastewater treatment, according to the characteristics of various substances in the wastewater, the treatment of wastewater is optimized in different ways, and the biodegradability is gradually improved.
This technology can already process macromolecular organic matter, and the completion time is 3 hours, which makes the treatment more efficient, and tries to completely eliminate the organic matter in the wastewater.
Strong resistance to load impact: In the process of actual wastewater treatment, the volume load can directly affect the final treatment effect. If the load is small, it will inhibit the growth of microorganisms. If the load is too large, it will also cause the content of a certain substance to be too high. , lose control of pH.
Therefore, reasonable control of the volume load is the guarantee to improve the efficiency of wastewater treatment. The technicians in the case have determined through experiments that when the volume load of BOD5 is between 1.14 and 6.56kg/m3/d, it has a strong resistance to load impact.
2.2 Technical Mechanism
Its technical mechanism includes two points: First, due to the unique structure of the hydrolysis and acidification reaction device, it can significantly improve the mass transfer performance.
During the process of wastewater treatment, the flow distance will continue to shrink due to the blocking of the plate and the plate, and turbulent flow will gradually form. Shear flow occurs at the location, and vortex groups of different sizes appear, which induces local diffusion.
Although the vortex area that appears is small, it can also expand the range of molecular flow to a certain extent, shorten the distance between diffusion and diffusion, and make the volume of the solute uniform, thereby accelerating the speed of biochemical reactions.
At the same time, during the reaction of the reaction device, a large number of vortex motions will generate multiple surfaces where the biofilms stay, and the surfaces are constantly updated, which promotes the contact between beneficial bacteria and wastewater, and further accelerates the speed of the biochemical reaction.
However, it must be noted that if strong turbulence occurs during the process, the technician can use the operation of each part of this turbulence control device to take advantage of the small vortex motion to thin the thickness of the retention film to speed up The speed of mass transfer.
At the same time as the thickness of the retention membrane becomes thinner, the amount of organic matter on the membrane surface also increases greatly. Once there is a deficiency, it can be replenished in time, which can speed up the spread of organic matter.
In addition, small vortices can quickly transfer the products of biochemical reactions, speeding up the replacement of old and new microorganisms.
Secondly, the buffer capacity of the system is improved, making wastewater treatment more efficient.
The use of Na2CO3 in wastewater treatment is to adjust the pH of the wastewater solution, thereby enhancing the buffer capacity of the system and effectively avoiding the increase in the number of organic acids. If the organic acid increases, the pH value will drop rapidly and affect the survival of microorganisms, so as to ensure The effect of acidifying bacteria is fully exerted.
After the buffer capacity of the system is significantly improved, the activity of the biofilm is also increased, which speeds up the biochemical reaction.
Treating wastewater with high-efficiency hydrolysis and acidification technology can optimize the treatment of wastewater, speed up the reaction of various substances in wastewater, and improve the speed of biological reactions.
At the same time, it can also strengthen the buffer capacity of the system and accelerate the generation and outflow of microorganisms during processing, showing the characteristics of high efficiency. But we still need to further improve the technology based on the existing technology to speed up the processing speed of the reactor.