Research On Hydrogen Sulfide Gas Drainage Network Source Identification And Diagnosis

So far,most of the research on hydrogen sulfide in drainage networks in China has been conducted around the generator and control theory of hydrogen sulfide.However,it is difficult to study the distribution and change rules of hydrogen sulfide in the actual network of pipeline networks.Realize the control of hydrogen sulfide in the actual pipe network.In this paper,the hydrogen sulfide in drainage network of a city in the south is taken as the research object,and the generation rules and influencing factors of H₂S in the inspection wells and auxiliary construction facilities of the drainage network system are studied.By monitoring the hydrogen sulfide gas at a certain time in a certain area of a certain city,the distribution of hydrogen sulfide gas at different characteristic points of the drainage network and the influencing factors in the pipeline network are analyzed,and the influencing factors such as rainfall,flow and temperature are examined.In terms of conditions,the factors affecting the release of hydrogen sulfide from the drainage network are described.The results of the study are as follows:?1?Drop wells in each type of zone contribute most to the production of hydrogen sulfide.When the temperature in the well is between 8? and 16?,the maximum concentration of H₂S is 12ppm;when the temperature in the well is between 16? and 24?,the maximum concentration of H₂S is 16ppm;when the temperature within the well is between 24? and 32?,the maximum of H₂S is highest.The concentration is 35ppm;when the air temperature in the well is above 32?,the maximum concentration of hydrogen sulfide exceeds 60 ppm.?2?For the H₂S in the branch pipes of each area,the influence of temperature is different.When the air temperature in the well is between 8? and 16?,the hydrogen sulfide in the branch pipes in most areas is almost disappearing.When the temperature in the well is between 16? and 24?,the hydrogen sulfide in the branch wells is mostly distributed around 10 ppm.?3?For special structures,such as grid wells and septic tank wells,there is no hydrogen sulfide gas,but the wells are covered by scum for a long time,and the anaerobic environment is good,which facilitates the SRB bacteria to consume sulphate to produce sulfide,and the accumulated vulcanization The material will be released into hydrogen sulfide in the downstream drop well.?4?Hydrogen sulphide was not detected before the grid of the pumping station,but hydrogen sulfide was monitored in the downstream pressure relief well,and the fluctuation of hydrogen sulphide was positively correlated with the fluctuation of pump station flow.?5?Most trunk gravity wells have no hydrogen sulfide,but if there is higher hydrogen sulfide gas in the upper part of the gravity well of the trunk,the hydrogen sulfide will be transferred to the gravity well trunk.?6?Rainfall has a certain flushing effect on sediments in the wells,which will change the original distribution of SRB bacteria on the surface of sediments.After the rainfall,the original hydrogen sulfide in the well will decrease instantly.After the rain stopped,the hydrogen sulfide in the well slowly returned to its original state.The well with the fastest recovery time was 21 hours,and the slowest well was about 41 hours.The recovery time is affected by the incoming water conditions in the well.?7?Gravity wells,when the liquid level suddenly rises and falls,will lead to the release of hydrogen sulfide.