Study On The Performance Of Special S-shaped Trap

Building waste water drainage system is used to collect and discharge the waste water from people’s daily life and production,which is closely related to people’s life.Trap is one of the most important parts of the construction wastewater drainage system,which can prevent the poisonous and harmful gas from entering the room and ensure the safety of the indoor environment.Since the 20 th century,the research has focused on the pressure fluctuation of the building drainage system and the height of the trap,but there is little research on the practical application of the trap,In this paper,the performance of special S-shaped trap is studied through the following three experiments:First,the installation height test of special S-shaped trap under constant discharge of ordinary single riser drainage system.The influence of different installation height of special S-shaped trap on the pressure fluctuation and water seal performance of horizontal branch pipe is studied under the condition of constant discharge with different drainage flow,and the optimal installation height of special S-shaped trap is obtained.The results show that under the same drainage flow,the higher the installation height of the special S-shaped trap,the lower the maximum positive pressure,maximum negative pressure and average pressure,and the smaller the water seal loss.Under the condition of the same positive and negative pressure in the horizontal drainage branch,the higher the installation height of the special S-shaped trap,the harder the pressure in the horizontal drainage branch will affect the trap,and the smaller the water seal loss.The recommended installation height of the special S-shaped trap is 60-90 cm.Second,the special S-shaped trap simulation of the sewage discharge effect test.The effect of the drainage height,discharge flow and drainage time on the discharge rate of the sewage in the water trap is studied by combining the wash basin with faucet to simulate the drainage of the basin.The optimal drainage time and discharge flow and the drainage height of the special S-shaped water trap are obtained.The results show that the higher the drainage height of the washbasin,the greater the discharge flow,the greater the flow velocity entering the trap,the stronger the drag force of the water flow,the easier the dirt is to be discharged in the special S-shaped water trap,so the effect of the drainage time on the discharge rate of the dirt is less.It is suggested that the drainage height of special S-shaped water trap should be set as 30 cm-40 cm,and the drainage flow should be ≥ 0.15 L / s.Thirdly,the test results are verified on other types of drainage systems.Based on the above test results,the optimal installation height and drainage height of special S-shaped trap are obtained,and the drainage verification is carried out on other types of drainage systems(special single riser drainage system,suction valve ventilation drainage system).The results show that the water seal loss of special S-shaped trap is less than 30 mm when the pressure of horizontal branch pipe is ± 400 pa,and the remaining water seal height is enough to cover the evaporation loss in the next two weeks.Therefore,the special Sshaped trap with installation height of 60 cm can meet the drainage requirements of these two drainage systems.