《泵站设计关键》PPT课件.ppt

1,Key Factors for PS Design 泵站设计关键因素,2,Installation 安装位置 Inside/outside, on or below the floor, etc 室内/室外， 地面/地下等 Size of the installation 安装尺寸 Wastewater, rainwater flow, Head 污废水，雨水的流量、扬程 Material 材料 Concrete, fibre glass, polyethylene, etc 混凝土、玻璃钢或聚乙烯等 Requested equipments 设备要求 Screen, separate valve chamber, level switch, etc. 格栅、独立阀门井、液位开关等,Before we can select the right pumping station, we need to know? 在泵站设计前，我们需要知道？,3,Basic process of PPS design 泵站设计基本步骤,Pump design finished 泵站设计完成,Pump selection 选泵,Designed inflow, head 设计入流流量、扬程,Related information collection 相关信息收集,Elevation of ground, inlet and discharge 地面、进出水管标高,Confirm effective Volume 确定有效容积,Confirm stop level 确定停泵水位,Confirm start/stop number 确定启动次数,Confirm distance between start and stop level 确定启停液位距离,Tank diameter 井筒直径,4,Sizing of wastewater pumping station 污废水泵站尺寸,Minimum volume 最小容积,Effective volume 有效容积,1,2,3,4,Ground level 地面标高,5,6,Top cover顶盖,Discharge port出水端,Alarm level 报警液位,Inlet port 进水端,Start level 启动液位,Bottom底部,Stop level停泵液位,5,The depth of the minimum volume must be high enough to avoid the pump sucking air 最小容积高度应该避免水泵吸入空气 Direct fall from the inlet should be minimized to avoid air in the pump 进水管跌水高度最小化，避免水泵吸入空气 Maximum velocity of water intake : 1,2 m/s 最大入流流速1,2 m/s Inclined bottom (45 to 60)（PUST） 底部倾斜(45 to 60)(PUST),1 - Minimum volume 最小容积,Baffle缓冲高度,Minimum volume 最小容积,1,Bottom 底部,Stop level 停泵液位,6,Minimum diameter at the bottom （PUST）increases the water velocity and facilitate the pumping of solid matters 底部直径缩小(PUST)增加了水的流速，有利于泵送固体介质 Minimum stop level for SE1/SEV with stainless steel jackets is just above the pump housing 不锈钢外壳的 SE1/SEV的最低停泵液位为水泵涡壳以上 For other pumps: Stop level at least in the middle of the motor 对于其他的水泵：停泵液位最低至电机的中部,1 - Minimum volume 最小容积,Baffle缓冲高度,1,Minimum volume 最小容积,Bottom 底部,Stop level 停泵液位,7,It is very important to get the distance between start and stop right. 启/停液位之间的距离非常重要 The start level and stop level must be as close as possible to 启停液位应尽可能满足 design the tank size by optimizing the effective volume 优化有效容积,设计井筒尺寸,At least at the top of the motor 最小到电机的顶部,Effective Volume 有效容积,2,Start level 启泵液位,Stop level 停泵液位,2 - Effective Volume 有效容积,8,It is very important to get the distance between start and stop right. 启/停液位之间的距离非常重要 The start level and stop level must be as close as possible to 启停液位应尽可能满足 design the tank size by optimizing the effective volume 通过优化有效容积设计井筒尺寸,At least at the top of the motor 最小到电机的顶部,Effective Volume 有效容积,2,Start level 启泵液位,Stop level 停泵液位,2 - Effective Volume 有效容积,9,The start level and stop level must be as close as possible to 启停液位的距离应尽可能小，从而 shorten the stay time of the wastewater 缩短废水停留时间 Reduce the performance variation Q, H and 减少 Q, H and 的变化,At least at the top of the motor 最小到电机的顶部,Effective Volume 有效容积,2,Start level 启泵液位,Stop level 停泵液位,2 - Effective Volume 有效容积,10,2 - Effective Volume 有效容积,The right distance between start and stop is very important: 启停液位之间的距离非常重要 To short a distance may cause overload of the motor due to many start and stop. 距离太近，电机频繁启停导致过载。 To long a distance may cause sedimentations and risk for clogging due to long stay time in the pit 距离太远，水泵运行周期过长，增加了沉淀和堵塞的风险 The right distance will give the optimal tank size 正确的启停液位距离是池型优化设计的关键,11,T = Pumping cycle period 水泵运行周期 Ts = Stopping period 停泵周期 Tp = Pumping period 泵送周期 T=Tp+Ts,2 Calculating the effective volume theory 有效容积计算原理,Start,Stop,Zmax = maximum number of start-stop /hour 每小时 最大启停次数 = minimum cycle period h = T 最小运行周期,12,Qww/Qp,Pumping period Tp 泵送周期 Stopping period Ts 停泵周期 Cycle period Tp + Ts 运行周期,If Qww= pump capacity = 1 then: 如果Qww= 泵送流量 = 1 ，那么 Pumping time TP = infinite 泵送时间TP= 无限大 Stopping time TS = 0 停泵时间TS = 0,If Qww= 0 then: 如果Qww= 0 ，那么 pumping time TP = 0 泵送时间TP = 0 Stopping time TS = infinity 停泵时间TS = 无限大,Minimum cycle period = 最小运行周期,2 Calculating the effective volume theory 有效容积计算原理,When Qww /Qp = 0,5 then Tp =Ts : 当Qww /Qp = 0,5 时，Tp =Ts : the number of start/stop is maximum and the cycle time is minimum 启停次数最大，运行周期最短,0 0,5 1,T,=,=,Tp,Ts,13,2 Calculating the effective volume theory 有效容积计算原理,When calculating the distance between start and stop (Heff), we need to know: 计算启停液位距离(Heff)，需要知道 Pump capacity Qp m3/h 水泵的运行流量 Incoming flow Qww m3/h 入流流量 Pit diameter mm 泵坑直径,Calculating the minimum start and stop period 计算最小启停周期,H eff,14,Monogram for the determination of the accumulated volume between start and stop (Veff),Calculating the effective volume 计算有效容积,2 Calculating the effective volume theory 有效容积计算原理,Calculating the height between start and stop level 计算启停液位距离,15,For two pumps in alternating operation 对于双泵交替运行,Note : 说明： Only one pump is taken into account for the calculation, the pumps alternate between duty and standby position with each running cycle. 当有效容积计算时只考虑一台泵，双泵按运行周期交替运行 The pumps are calculated for the peak flow 水泵流量按照峰值流量计算 In case of very small incoming flow, the velocity in the raising main must be high enough to prevent sedimentation. 当流量非常小时，上升管的流速必须足够大以避免沉淀,2 pumps in alternating operation where Qin QPump 当Qin QPump，2台泵交替运行,2 Calculating the effective volume theory 有效容积计算原理,16,2 pumps in alternating operation where Qin QPump 当Qin QPump，2台泵交替运行,Pump A,Pump B,TP TS TP,A,A,B,B,A,TS TP,Note : 说明： If the incoming flow exceed the capacity of the duty pump, the pump in standby position will start and 2 pumps are operating in parallel. 如果入流流量超过工作水泵流量，备用水泵启动， 双泵并联运行 the pumps can be calculated for the incoming flowpeak flow. If one pump fails, the wastewater level in the pit can raise. 可以按照入流流量峰值流量计算水泵流量，如果 一台泵故障，允许泵站水位升高,2 Calculating the effective volume theory 有效容积计算原理,For two pumps in alternating operation 对于双泵交替运行,17,Pumping stations with more than two pumps : 超过两台泵的泵站 The effective volume can be reduced when the pumps are working in parallel and assume alternately the position of duty and standby with each running cycle : 水泵并联运行，按运行周期交替运行，有效容积减小,n = number of pumps excluding the spare pump 除备用泵以外的水泵数量,2 - Effective Volume 有效容积,18,2 - Effective Volume 有效容积,传统泵站计算方法给水排水设计手册（第五册）城镇排水,19,2 - Effective Volume 有效容积,传统泵站计算方法给水排水设计手册（第五册）城镇排水,20,Exercice 练习,Qp = 52,8 l/s 2 pumps in alternating operation 双泵交替运行 Circular tank : diameter 2300 mm 圆形池：直径2300mm,Information given: 已知信息,The effective volume Veff 有效容积 Veff,Calculate: 计算,21,Correction 正确的计算,Circular tank : diameter 2300 mm, R=1,15 m 圆形池：直径2300mm,R=1.15M,Qin = 52,8 l/s is equal to 190 m3/h Qin = 52,8 l/s 等于 190 m3/h,r,Veffective,Heffective,22,3,3 +4 distance 距离,Distance 3 is about 10 cm 距离3大约10cm Distance 4 is about 10 cm, but it can be choosen by the customer 距离4大约10cm,但可由客户选择,110 mm,Minimum volume 最小容积,Effective volume 有效容积,1,2,4,Alarm level 报警液位,Inlet port 进口端,Start level 启泵液位,Bottom 底部,Stop level 停泵液位,23,Pumping station sizing 泵站尺寸,Distance 5 frost-free depth or local regulations 距离5为冰冻线以下或按照地方法规 Distance 6 Minimum 5 cm to prevent water from entering the pit 距离6最小为5cm，防止水从顶盖进入泵站 Distance 5 and 6 must be given by the customer 距离5和6应由客户提供,Ground level 地面标高,5,6,Top cover顶盖,Discharge port 出口端,24,Pumping station sizing - 2 pumps 泵站尺寸双泵,Pumping cycle two pumps 两台泵泵送周期,Bottom底部,Stop level停泵液位,Inlet port 进口端,Start level pump 1 水泵启动液位1,Minimum level 最小液位,Effective level 有效液位,1,2,Start level pump 2,Distance between start levels about 10 cm 启动液位之间的距离约10cm,Start level pump 2 水泵启动液位2,Alarm level 报警液位,25,The right pumping station for the customers need 符合客户需求的泵站,FAQ (Frequently asked questions) （常问问题）,26,How can I protect the pit from uplift ? 如何抗浮,In area with high groundwater-level, or in area with high possibility for heavy rain there is a risk for uplift. 在地下水位较高的区域，或在可能会降暴雨的区域，存在泵站上浮的风险。 Uplift is an situation where the pit can be lifted up from the ground by the water-pressure. 上浮位置为泵站在水的浮力作用下可能会浮起的位置。,Situation情形,27,What is uplift? 什么是上浮,Archimedes principle: principle that states that a body immersed in a fluid is buoyed up by a force equal to the weight of the displaced fluid. 阿基米德定律： 浸入液体的物体所受的浮力等于排出液体的重力,The force from the uplift (FUplift) is equal to the weight of the displaced water 浮力(FUplift)等于排出液体的重力,FUplift,Displaced water 排出液体,28,Formula for calculating the weight of displaced water 计算排出液体重量的公式 The uplift must be prevented by making an slightly bigger down force 通过比浮力大向下的力抗浮 Fdown FUplift Putting material around the slab area, will create the Fdown 在底部区域放置重物能产生向下的力 Density of concrete/gravel : water = 2 - 2,5 混凝土的比重 Density of water : water = 1 水的比重,Slab area (sa),The trick is to make the pit heavier than the weight of t