Intermittent water supply biological filter

Abstract

The invention discloses a wastewater treatment system for a novel intermittent water supply biological filter. The novel biological filter is improved from an ordinary biological filter, employs a mixed filter material with relatively small particle sizes to improve an effect of water treatment, and adopts a method of frequently alternating waterflooding states and air-drying states of a filter material layer and installing bottom vent pipe, to replace a natural ventilation for oxygenating and to avoid a blockage of the filter material layer. The intermittent water supply biological filter adopts broken stones (gravels) with particle sizes of 1-2 centimeters mixedly incorporated in particles, with the same size, of magnetite, graphite (or nut shell activated carbon), volcanic, limestone and activated zeolite, as filter materials for water treatment, and can adopt filter materials with diameters of 0.5-1 centimeters if pollutant concentrations of inlet water are relatively low. A height of the filter layer is 1.5- 2 meters; an intermittent quick water distribution is adopted; usually, a water distribution time for every water distribution is 20 minutes; an air-drying state lasts for 60-120 minutes; and a hydraulic load is designed for 2-4 m3/m2d. The biological filter has the advantages of good water quality for outlet water, high hydraulic load, low investment, low energy consumption, low operation cost and simple management, and is particularly suitable for treating domestic wastewater of small cities.

Description

technical field [0001] The invention is a new type of biochemical plus physical chemical treatment process in the field of sewage treatment, which is mainly used in the treatment of domestic sewage in small and medium-sized cities and towns. The biofilter, that is, the intermittent feed type biofilter. Background technique [0002] Ordinary biological filter (biological filter, trickling filter) uses natural ventilation to provide oxygen for biological growth. A biological treatment structure composed of gravel or plastic filter media. The sewage is in contact with the microbial film growing on the surface of the filler to purify the sewage. Biological filter is an artificial biological treatment technology developed based on the principle of soil self-purification, based on the practice of sewage irrigation, and through the relatively primitive intermittent sand filter and contact filter. [0003] The treatment effect of the ordinary biological filter is very good, and i...

AI Technical Summary

Problems solved by technology

In order to avoid biofilm blockage caused by too small pores of the filter material and insufficient ventilation and oxygen supply of the filter bed, the present invention adopts intermittent rapid water distribution to cause the filter material layer to be flooded and dry alternately, and utilizes the negative pressure formed by the slow falling of the stagnant water surface The air is brought into the filter material layer, so that the filter material layer with a smaller particle size can also obtain better ventilation and oxygenation, thereby solving the problem that ordinary biological filters cannot use small particle size filter materials with natural ventilation.

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