Integrated wastewater treatment equipment is mainly to achieve the treatment of sewage from centralized to decentralized, from large-scale centralized to small and medium-sized decentralized transformation and the development of a small infrastructure investment, covers an area of small, reduce the construction of pipeline networks and other characteristics, widely used. Integrated wastewater treatment equipment, there are four main processes:
1, A/O process
A / O process is to activated sludge as a biological carrier, through the role of the fan oxygen aeration so that the sewage to achieve the purpose of oxygenation.A pool is equipped with mechanical mixing, from the O pool of the reflux liquid refluxed to the pool of A, the pool of denitrification reaction in the pool of A, most of the nitrate nitrogen reduction into nitrogen, and through the mixing to make nitrogen from the wastewater, the nitrate nitrogen from the wastewater. Stirring makes the nitrogen overflow from the wastewater to achieve the purpose of removing ammonia nitrogen; A pool of water to O pool, O pool is equipped with blast aeration to remove most of the organic pollutants, and most of the ammonia nitrogen in the influent water is converted into nitrate nitrogen; according to the needs of the wastewater, the concentration of the activated sludge in the O pool can be adjusted to adsorb, oxidize and decompose the organics in the wastewater by the bacterial colloid in the activated sludge; the removal rate of the organics, ammonia nitrogen is High. However, since there is no independent sludge return system, thus sludge with unique functions cannot be cultivated, and the degradation rate of difficult-to-biodegrade substances is low; at the same time, if the nitrogen removal efficiency is to be improved, it is necessary to increase the ratio of the internal recirculation, which increases the operation cost. In addition, the internal circulating liquid comes from the aeration tank, which contains a certain amount of DO, making it difficult to maintain the ideal anoxic condition in section A, affecting the effect of denitrification and making it difficult for the nitrogen removal rate to reach 90%.
2, SBR process
SBR process is developed in recent years, a more advanced activated sludge treatment method, the treatment process set of aeration tanks, sedimentation tanks as a whole, continuous water intake, intermittent aeration, stopping the sewage precipitation skimming supernatant, a cycle, week after week. SBR method does not set up sedimentation tanks, no sludge reflux equipment, but the SBR process for intermittent operation, the need for multiple treatment units, the need to set up a number of treatment units. SBR method does not set up sedimentation tank, no sludge return equipment, but the SBR process is intermittent operation, need to set up more than one treatment unit, water intake and aeration switch each other, resulting in more complex control. In order to ensure that the overflow rate, SBR process on the decanter equipment manufacturing requirements are high, the production must strive for excellence, otherwise it is very easy to cause the final effluent water quality does not meet the standards. At present, there is no good quality decanter equipment, imported equipment purchasing trouble, and expensive, while the late maintenance costs are also high.SBR process pool sludge concentration determined by the concentration meter in order to control the amount of excess sludge discharged, the current domestic concentration meter technology is immature, such as the reasons easily caused by the SBR sludge discharge control difficulties and other issues.
3, contact oxidation process
Bio-contact oxidation is a traditional biochemical treatment method, biological filler for the fixed bed of semi-soft filler. The use of semi-flexible filler as a microbial attachment carrier, biological uniform distribution in the biological filler, so as to avoid the phenomenon of uneven distribution of microorganisms, at the same time, biological attachment to the surface of the filler, not with the flow of water, because the biofilm directly by the strong stirring of the rising airflow, constantly updated, thus improving the purification effect. The contact oxidation method has the advantages of short treatment time, small volume, good purification effect, good and stable quality of effluent water, sludge does not need to reflux or expansion, small power consumption.
4, MBR process
MBR is a new type of high-efficiency sewage treatment process combining high-efficiency membrane separation technology and traditional activated sludge method, it has a unique structure of submerged membrane components placed in the aeration tank, aerobic aeration and biological treatment of water, pumped through the membrane filtration pumped out. It is very different from the traditional sewage treatment methods, replacing the traditional biochemical process in the second sedimentation tank and tertiary treatment process, due to the presence of the membrane greatly improves the solid-liquid separation of the system, so that the system effluent water quality and volumetric loading have been greatly improved, combined with different processes, the effluent can reach the standard of landscape water or miscellaneous water. Due to the filtration effect of the membrane, microorganisms are completely retained in the bioreactor, realizing the complete separation of hydraulic retention time and activated sludge age, eliminating the sludge expansion problem in the traditional activated sludge method. Membrane bioreactor has the advantages of high removal efficiency of pollutants, strong nitrification ability, nitrification and denitrification at the same time, good denitrification effect, stable effluent water quality, low production of residual sludge, compact equipment, easy to operate and so on. At present, it is widely used in the treatment and reuse of domestic sewage and various biochemical industrial wastewater.
Two, integrated sewage treatment equipment process
Integrated wastewater treatment equipment for sewage treatment process is roughly: the sewage to be treated by the grid to remove the larger suspended solids after self-flow to the conditioning tank for equalization of the quality and quantity of treatment, and then lifting pumps up to the integrated wastewater treatment equipment, in turn, through the pre-denitrification area, anaerobic area, anoxic area and aerobic area of the biochemical processing After the sedimentation area to achieve mud-water separation, precipitation water finally through the ultraviolet sterilizer disinfection to achieve discharge. Specific processes are as follows:
1, grating
The sewage is collected and transported to the sewage treatment station through the pipeline network, and firstly, the large particles of solids or floating matter contained in the sewage are removed by the grating to ensure the stable operation of the subsequent treatment device, and the grating slag is regularly transported and disposed of.
2, regulating pool
The whole regulating system consists of regulating pool, lifting pump, liquid level meter and other auxiliary systems. Sewage in this flow and concentration of buffer and regulation, regulation of water, water quality into the subsequent biochemical treatment system of sewage indicators have a better stability, and promote the efficiency of the system. Sewage is lifted into the integrated wastewater treatment equipment by the lifting pump of the regulating pool.
3, integrated wastewater treatment equipment
Contains anaerobic tank, anoxic tank, MBBR aerobic tank, two sedimentation tanks, flocculation reaction tanks, high-efficiency sedimentation tanks, equipment room and supporting auxiliary units. The anaerobic tank and anoxic tank are filled with combined filler; the MBBR tank is filled with MBBR suspended filler, thus forming two kinds of macroscopic and microscopic A/A/O environments; the nitrification liquid at the end of MBBR aerobic tank is refluxed to the anoxic tank through the pump, and the sludge of the secondary sedimentation tank is refluxed to the anaerobic tank through the sludge pump. In the MBBR aerobic tank, the organic nitrogen in the sewage is converted into nitrate by ammonification and biological nitrification; in the anoxic tank, the denitrifying bacteria will convert the nitrate brought in by the internal reflux into nitrogen through biological denitrification, which will escape into the atmosphere, so as to achieve the purpose of complete nitrogen removal. In the anaerobic tank, the polyphosphorus bacteria in the return sludge release phosphorus and absorb easily degradable organic matter such as low-grade fatty acids; while in the MBBR aerobic tank, the polyphosphorus bacteria in the activated sludge over-absorb phosphorus and remove phosphorus by discharging the residual sludge through the second settling tank precipitation.
4, disinfection
Sedimentation effluent can be discharged after disinfection by ultraviolet sterilizer.
5, sludge pool
Integrated wastewater treatment equipment produced in a small amount of residual sludge is first discharged into the sludge thickening pool concentration, concentration of the supernatant back to the regulator, concentrated sludge is regularly disposed of for transportation.