The basic principle of septic tank is to remove and kill parasitic eggs and germs, control the breeding of mosquitoes and flies, and achieve the effect of harmless feces by using the precipitation caused by the specific gravity of parasitic eggs greater than the mixed liquid of feces and the principle of closed oxygen fermentation, liquefaction, ammoniation and biological antagonism of feces. The three-chamber septic tank consists of three adjacent ponds, in which the manure is fermented and decomposed for more than 30 days, and the middle-layer manure liquid flows from 1 pond to the third pond, so as to precipitate or kill parasite eggs and germs in the manure, and the manure liquid in the third pond becomes high-quality chemical fertilizer.
Second, the scale structure
The volume of three septic tanks shall not be less than 1.5 m? The ratio of three ponds is 2: 1: 3, that is, 0.5 m? : 0.25 meters? :0.75m？
The volumes of the first and second cylinders are 30 days, respectively, and the amount of urine and feces per person per day is1.5l. The water consumption can be calculated as 4L. If each household is calculated by 4-6 people, the volume of the first and second tanks should not be less than 660 l( 1 m3 is equal to 1 000l).
Volumes Calculate the effective volumes of the first and second tanks (m? ) = (population ×30 days × feces and urine and toilet water per person per day)/1000
Basic structure (1) A three-chamber septic tank consists of three connected tanks, and the volume ratio of each tank is 2: 1:3. The middle part is connected by two dung pipes, which is mainly based on the principle of anaerobic fermentation, and the ratio of dung and parasite eggs in the middle layer is heavier than that in the common mixed solution, and it is easy to precipitate. After more than 30 days of fermentation and decomposition, the manure in the middle layer flows from 1 pond to the third pond in order to precipitate and kill the pathogenic factors in the manure, and the manure in the third pond becomes harmless and high-quality ecological farm manure.
Basic structure (2) The access door of septic tank is sealed with a cover plate, which must be made of glass fiber reinforced plastic or cast iron, and the bearing capacity is not less than 500 kg. The cover plates of the first and second tanks must be clearly marked as one-time molding, which means harmful, and the cover plate of the third tank should be clearly marked as one-time molding, which means harmless. Cover plate and septic tank must have more than one locking device to prevent accidents caused by accidental opening.
Basic structure (3) There must be concave-convex structure at the upper and lower splicing parts of the integrated three-format septic tank, and seepage-proof gasket or structural adhesive must be installed in the groove during assembly to ensure no leakage. Screws shall be stainless steel of size 304 or above.
Basic structure (4) The septic tank should have a once-formed groove to place a partition to divide the tank into three compartments, and the groove should be seamless to ensure no leakage between the three compartments. There should be a locating bayonet at the joint between the partition and the tank to prevent displacement and leakage, and sealant should be applied to the upper and lower grooves during assembly.
Basic structure (5) Septic tanks are connected by dung pipes, which are respectively installed on two partitions. The dung pipe must be connected with the partition board with disposable plastic parts, and no metal parts are allowed at the joint. The two manure pipes are on the same horizontal line, not on a straight line, so they need to be staggered left and right to delay the flow speed of the liquid in the pool.