Quick-speed clarification tank

Abstract

The invention relates to an improvement on a clarification tank, which is characterized in that: a concrete reaction groove is arranged around the upper part of the wall of the clarification tank; a turbulent devices are arranged in the concrete reaction groove at intervals; vertical spaced corrugated boards are arranged in a built-in reaction chamber; a communicated water channel is arranged between the surrounding reaction groove and the concrete reaction chamber; and vortex coagulation reaction devices with a herringbone or reverse W-shaped structure are arranged at the middle lower part of the clarification tank at intervals. The improved clarification tank well solves the contradiction between full flocculation and land occupation and a plurality of times of mud and water separation due to the fact that the sedimentation, clarification and contacting sedimentation are completed in one tank. An outstanding characteristic of the improved clarification tank is fully improving coagulation and flocculation reaction effects and clarification and separation effects without increasing land occupation, so the clarification tank can realize quick clarification, strong processing capacity, land occupation processing capacity maximization, high-quality effluent and strong impact-resistant and loading capacity.

Description

technical field [0001] The invention relates to the improvement of clarifier tanks, in particular to a quick clarifier tank with high mud-water separation efficiency, small occupied area, short residence time, good effluent quality and low construction investment. Background technique [0002] The clarification tank is mainly used for surface water, high turbidity raw water clarification treatment, sewage and its reuse treatment, etc., to realize the separation of mud, sand and water to clarify the water as soon as possible. The efficiency of the clarification tank directly determines the area and investment cost of processing tons of water. In order to achieve rapid clarification, the existing technology mostly adopts a mechanically stirred clarifier tank that integrates mixing, flocculation reaction and sedimentation processes in one tank. The basic structure is as follows: Figure 8 As shown, in the circular pool 9, a mechanical agitation coagulation reaction tank and a cl...

AI Technical Summary

Problems solved by technology

The disadvantage of this type of clarifier is that the reaction water in the first-stage coagulation chamber is opened by a lifting rake and then enters the second-stage coagulation chamber for reaction. However, in actual operation, in order to reduce operational troubles, the operator usually The stirring rake is set to half rake or fully open state, causing the treated influent to rise directly to the second coagulation chamber without sufficient reaction in the first coagulation chamber, resulting in insufficient coagulation reaction, thereby reducing the subsequent clarification and separation effect , affecting the water quality of the effluent; in order to ensure the effect of treating the effluent, it is necessary to add a coagulant aid with a higher price, which significantly increases the operating cost

Secondly, there is only one mud-water separation in the clarification process (excluding inclined plate or inclined tube separation, the same below), the water stays for a long time, and the effluent is difficult to meet high requirements

Third, to deal with large volumes of water (eg 400m 3 / h and above) device, the structure determines that the rotary mud scraper can only be driven by pin-toothed disc, the pin-toothed disc is driven by bias, and the scraper arm of the mud scraper is a 360-degree trisection structure, which will cause the mechanical The instability of the structure, especially when the silt content in the influent is large, is likely to cause uneven force, which will cause the scraper arm to be twisted and deformed, which will affect the normal scraping and eventually damage the scraper; type mud scraper, and can only be used for small water treatment

Although this structure can use a central drive rotary mud scraper, there are still some deficiencies: for example, in order to improve the flocculation effect, the reaction zone is moved outside, which increases the floor area, and in order to ensure a good coagulation reaction effect, the reaction zone must have Sufficient area increases the land occupation, increases investment and cost, and fails to give full play to the characteristics of the small area occupied by the accelerated clarifier

The use of two-stage separate mechanical stirring and coagulation can avoid the impact of insufficient coagulation reaction caused by the operation and improve the coagulation effect. However, the side-by-side mixing tank also increases the floor area. If it is designed to be smaller, the coagulation The effect is increased but limited; and adding a mixing tank structure outside the tank is not conducive to the combined arrangement; secondly, although the upper and lower round clarifiers are conducive to the adjacent setting to reduce the footprint, the lower part is still used to adapt to the rotary mud scraping The circular cross-section does not give full play to the characteristics of the upper and lower square pools occupying the same area and the largest pool capacity, and the civil construction needs to be carried out twice. First, the upper and lower full-section square pools are excavated and masonry, and then the lower part is filled and repaired into a circular shape. , increase the cost of civil engineering; in addition, the overflow into the clarification tank after the coagulation reaction by violent mechanical stirring, the disturbance of the water is relatively large, which is not conducive to the realization of rapid separation and stable flow clarification, resulting in a long residence time of the treated water in the clarification tank , affect the processing efficiency or increase the pool capacity

Furthermore, there is only one mud-water separation in the clarification process, the separation efficiency is low, and only low turbidity water can be processed

[0005] The all-Chinese settling tank disclosed in Chinese patent CN1683049 is basically the same as CN1669945, except that the external mixing tank is reduced, which will obviously reduce the coagulation effect, and is also unfavorable for rapid clarification; in addition, the above-mentioned other deficiencies still exist

[0006] The above-mentioned improvements to the mechanically accelerated clarifier only overcome some of the shortcomings, and there is a phenomenon of "focusing on one thing and losing the other", that is, improving one aspect will cause losses on the other, and there are still some insurmountable defects, such as insufficient coagulation reaction It is sufficient, or the floor space and investment cost are increased to meet the coagulation reaction; therefore, the contradiction between the excellent coagulation effect and the large floor space has not been completely resolved, and the floor space is still relatively large to achieve rapid clarification

Secondly, they have two common shortcomings: first, the clarification and separation only have one mud-water separation, the separation efficiency is low, and the relative residence time is long, and only low turbidity water can be treated. For high turbidity water, either the treatment effect is difficult to guarantee, or the treatment Reduced ability

Second, due to the limitation that the rotary mud scraper can only scrape a circular area, at least the lower part of the clarification tank must still adopt a circular structure. Although there is a proposed upper square and lower circular tank structure, it still cannot fully utilize the maximum volume (same depth) Effect, the amount of treated water has not yet reached the maximum land occupation, and the co-construction of multiple pools cannot achieve the minimum investment because they cannot share the same wall

[0007] The applicant first applied for the Chinese patent CN1840220 water treatment sedimentation tank and mud scraper. Although a square sedimentation tank and a supporting rotary mud scraper scheme were proposed, it was only considered from the perspective of sewage treatment process sedimentation and failed to understand To the function and role in water clarification treatment

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