Study On Sludge Treatment And Disposal Technologies Of Urban Black And Odorous River

Dredging polluted sludge is an important measure to reduce the endogenous pollution in the water environmental governance projects.To reduce and dispose the polluted sludge produced by dredging is a key concern in the current scientific research and engineering production.Based on the Maozhou River watershed water environment comprehensive governance project,through the sediment detection,equipment selection,on-site investigation and analysis of dredging,and comparing the effects of the three sludge treatment plants,the study foucued on:urban river dredging technology,polluted sludge reduction treatment technology and the utilization technology of the sludge treatment output.This study mainly draws the following conclusions:(1)Affected by the domestic pollution and industrial pollution of the surrounding residents and factories,there is obvious siltation and serious pollution in the Maozhou river sediments.The content of volatile solids in sediments is between 8%?15%,heavy metal pollution thickness is between 1.0?1.5m,and the pollution was light beyond the depth of 1.5m.Excessive heavy metals were copper,zinc,nickel and chromium,of which copper and nickel pollution were most serious,copper up to 8 times over the standard,nickel up to 29 times over the standard,(2)For the 3 sludge treatment plants compared in this study,a stable dehydration and solidification same-position treatment process is adopted in the 1#plant,and the 2#plant adopts the stable dehydration-curing same-position treatment process,and the automatic mechanization reduction and solidification treatment m,ethod is supplemented,and the 3#plant adopts the automatic mechanized decrement and solidification treatment method.Through comparison and analysis of the sludge output from different processes,it is found that the physical and mechaniccal parameters of the sludge in the stable dehydration-curing same-position treatment process are better and the environmental protection index can meet the requirements,which is one of the best methods for disposing the sludge.(3)The sludge after treated can be utilized.The average moisture content of the mud cake treated after treatment was 30.1%,the total nitrogen was 1,277.6 mg/kg,and the total phosphorus content was 1,209.4 mg/kg.Mercury,lead,chromium,nickel,zinc and copper were averaged at 1.8 mg/kg,36.6 mg/kg,286.7 mg/kg,174.8 mg/kg,361.7 mg/kg and 358.8 mg/kg.Although there are some fluctuations in the content of heavy metals in the output,most of them do not reach the strong variation degree,and they do not exceed the standard content,and can be further utilized.(4)The study puts forward the resource utilization technology of the sludge,and realizes the engineering application.The design of river dredging scheme will produce 174,400m3 rubbish in the process of sludge treatment and disposal=,which can be transported to a refuse incineration power plant for incineration or transportation to landfills for landfill;the resulting 355,300 m3 sand material can be used for resource utilization after cleaning,for embankment and land building,etc.Some of the mud cake(heavy metal leaching concentration of sludge after disposal satisfies the(Hazardous Waste Identification Standard,GB5085.3-2007 requirements)through high-temperature rotary kiln can be fired into different sizes of ceramsite,as a landscape paving bricks raw materials,building insulation filler,landscape potted materials,such as the use of resources.