Analysis And Structure Design For Fluid-solid Separation System Of Mixed Sewage

Currently,56million tons of manure is produced by700million urbanpopulations every day, toilet water and domestic waste water is five times the amountof manure, so the total of fecal sewage reaches to336million tons will enter the cityseptic-tanks. At this stage, it usually transported to a sewage treatment plant throughsuction-type tumbrel tanker, which is time-consuming, high cost, and even causessecondary pollution.This paper, aiming at the currect status of dirt mixed septic treatment, based onthe theory of vibrating sieve and screw extrusion principle, proposaled fluid-solidseparation program of septic tank mixing dirt, completed the preliminary prototypedesign and testing. The mainly research results of this paper are as follows:(1) This paper first proposed fluid-solid separation of septic tank mixing dirt " insitu" rapidly processing solutions by vacuum sewage suction pump functioning it intwo levels process, the first-class level using two motors elliptical vibrating sieve forearly separating coarse particle objects; Filtrate after chemical flocculation byconnecting a hose into the second stage screw press separator, dehydration squeezeseparation to achieve a fluid-solid separation of mixed dirt, The filtrate and fineparticles can be recycled and reused.(2) Based on the theory of vibrating sieve principle, it proposed dual-motorvibrating sieve balanced elliptical overall design, screening materials are factors suchas the nature of the structure of the fluid-solid separation for the type, sport, vibrationcharacteristics analysis results. The corresponding design parameters: the screensurface aspect ratio2.5, the round aperture20mm and the throwing index of3to5,theoretical and numerical analysis confirmed its legitimacy.(3) Based on the theory of the screw extrusion principle, the overall design ofscrew extruder is proposed, aiming at the analysis about the facts as screw shaft, sievedrum, the angle of inclination, the rotating speed to screw extruder separation, has gotthe corresponding design parameters: the aspect ratio of the helical axis3to6, wedgemesh drum sieve slit0.5to1mm and the installation angle10°, theoretical andnumerical analysis confirmed its legitimacy.(4) Based on the effective size of the configuration space is proposed layoutscheme fluid-solid separation systems, completing the cleaning system improveddesign by exchanging the wedge-shaped sieve drum to static ring and single-screw extruder to the double helix, which it prompting the two spiral between the bladesscratching each other and eliminating the sieve slit clogging phenomenon thatdifficult to clean, so that the structural design is more reasonable.