The Physical Performances Of Granular Sludge In Spiral Symmetric Stream Anaerobic Bioreactor

Energy shortage and environmental pollution are two major survival pressures in the world, and the application of anaerobic digestion technology to organic wastewater treatment can eliminate pollutants as well as produce bioenergy, which will play a great role in energy-saving and emission-reduction. Anaerobic reactor is the core of digestion technology, but the anaerobic granular sludge is the core of Anaerobic reactor. The research of anaerobic granular sludge have promoted the development of anaerobic reactor and enriched the theory of anaerobic digestion technology.This work studies the physical performances of granular sludge in spiral symmetric stream anaerobic bioreactor,which reactor have proprietary intellectual property rights. This paper systematicly research the performance and characteristics of granular sludge in spiral symmetric stream anaerobic bioreactor. The main points are summarized as follows:(1) Performance testing of the spiral symmetric flow anaerobic reactor.SSSAB is better than UASB on removal efficiency of CODcr of sewage, when the organic loading of the influent from1.26to8.82g·L-1·d-1, and the highest removal rate and the average removal of up to97.23%,85%respectively. The anaerobic granular sludge mostly exhibit spherical or elliptical-shape with clear outline. The scanning electron microscopy image shows has a porous and non-layered structure. the anaerobic granular sludge of UASB gradually become gray and flocculent sludge significantly in late emergence, but the anaerobic granular sludge of SSSAB can Keep deep black and complete state of particles.(2) Having revealed the physical performances of granular sludge in SSSAB.①SSSAB is better than UASB on The developmental stability of granular sludge stability. The average absolute value of zeta for each sample from40to50mv, which larger than floc sludge. Because of the average absolute value of floc sludge from8to18mv.②Granular sludge in the upper two developmental state is better than that of the lower part of the reactor, but growth condition is better than that of UASB granular sludge in SSSAB reactor.The granular sludge zeta variance of Samplel, Sample2and Sample3were130.8,90.04,31.36for SSSAB and for UASB were204.3,159.7,92.71.③The granular sludge in SSSAB on organic matter rate and the removal rate of COD is better than UASB, and the granular sludge with strong hydrophobicity in UASB reactor. The granular sludge in SSSAB surface contact angle and the removal rate of COD range from65.82°to106.26°, and from87.8%to94.72%; the contact angle and the range of removal rate of COD surface of granular sludge in UASB was from65.66°to98.38°,from49.57%to92.02%.④The spatial gradient distribution of granular sludge in SSSAB, and contact angle of the surface of reactor operation in the overall upward trend, however the UASB reactor with no obvious trend. Granular sludge surface contact angle were respectively83.56°and81.78°of Sample2and Sample3in UASB. However granular sludge surface contact angle were respectively99.49°and92.97°. of Sample2and Sample3in SSSAB.⑤The granular sludge wet density stability were enhanced with the reactor from bottom to top in SSSAB bed, and UASB does not have the rule change. The sludge in SSSAB reactor wet density variance of S2Sampie1>S2Sample2>S2Sampie3(0.0095>0.0049>0.0029).⑥The bed of granular sludge sedimentation performance is better than UASB. For the two reactor operation stage of granular sludge bed wet density, SSSAB has85.7%sludge wet density average value is greater than1g/cm3, UASB66.7%sludge wet density average value is greater than1g/cm3.⑦The content of Ca, Cu and other elements in SSSAB was significantly higher than that in activated sludge.The Ca content range from12.8to14.7mg· gSS-1, and the Cu content ranges from2.86to15.1mg·gSS-1in SSSAB. The Ca content range from2.9to3.5mg·gSS-1, and the Cu content ranges from0.23to0.87mg·gSS-1in UASB.⑧The metal elements in the SSSAB has a certain gradient distribution, by Ca, Mg and Cu. With the reactor operation, the content of metallic elements Ca, Fe, Cr increased with increasing the height of reactor, which is conducive to the maintenance of granular sludge shear capacity. And UASB does not have the rule change.