V型滤池计算(自编)

一、设计参数确定,,,,,,,,,,,

,设计水量,Q,=,80000,m³/d,,,,,,

,,,=,3333.333333,m³/h,,,,,,

,滤池冲洗确定(见下表),,,,,,,,,,

,,冲洗强度(L/S.㎡),,冲洗时间(min),,,,,,,

,第一步(气冲),15,,3,,,,,,,

,第二步(气水同时冲洗),空气,15,4,,,,,,,

,,水,4,,,,,,,,

,第三步(水冲),5,,5,,,,,,,

,则总冲洗时间,t,=,12,min,,,,,,

,,,=,0.2,h,,,,,,

,冲洗周期,T,=,48,h,,,,,,

,反冲横扫强度,,=,1.8,L/(s·㎡),,一般取1.4-2.0L/（s*㎡）,,,,

二、滤池计算,,,,,,,,,,,

,滤池滤速,V,=,10,m/h,,,,,,

1、,滤池工作时间,t’,=,23.9,h,,,,,,

2、,滤池总面积,F,=,334.7280335,㎡,,,,,,

,滤池组数,N,=,2,座,,,,,,

,每座滤池格数,n,=,4,格,,,,,,

,单格滤池面积,s,=,41.84100418,㎡,取长度,12,m,宽度,3.486750349,m

3、滤池高度确定,,,,,,,,,,,

,滤池超高,H5,=,0.3,m,,,,,,

,滤池口水深,H4,=,1.5,m,,,,,,

,滤层厚度,H3,=,1.4,m,,一般取(0.95～1.50m),,,,

,滤板厚,H2,=,0.15,m,,,,,,

,滤板下布水区高度,H1,=,0.9,m,,一般取(0.70～0.90m),,,,

,滤池总高度,H,=,4.25,m,,,,,,

4、水封井设计(不用管道排水则有水封井和溢流堰),,,,,,,,,,,

,"滤池采用单层加厚均粒滤料,粒径0.95～1.35㎜,不均匀系数1.20～1.60

均粒滤料清洁滤料层的水头损失按下式计算

",,,,,,,,,,

,,,,,,,,,,,,

,"式中:

△—水流通过清洁滤料层的水头损失,㎝;

",,,,,,,,,,

,"V—水的运动黏度,cm2/s;20℃时为0.0101cm2/s

",,,,,,,0.0101,cm2/s,,

,"g—重力加速度,981cm2/s2;

",,,,,,,981,cm2/s2,,

,"m0—滤料孔隙率;取0.50;

",,,,,,,0.5,,,

,"d0—与滤料体积相同的球体直径,㎝,取=0.141cm;

",,,,,,,0.141,cm,,

,"—滤层厚度,=140cm。",,,,,,,140,cm,,

,"v—滤速,㎝/s,v=10m/h=0.28㎝/s;

",,,,,10,m/h,0.277777778,cm/s,,

,"∮—滤料粒径球度系数,天然砂粒为0.75～0.8,取0.75",,,,,,,0.75,,,

,,△H,=,12.88901265,cm,,,,,,

,"当滤速为8～10m/h时,清洁滤料层的水头损失一般为30～40㎝,计算值比经验值低,取经验值的低限30㎝",,,,,,,,,,

,"为清洁滤料层的过滤水头损失,正常过滤时通过长柄滤头的水头损失△h=0.20m,忽略其他水头损失,",,,,,,,,,,

,"则每次反冲洗后刚开始过滤时,水头损失为:",,,,,,,,,,

,清洁滤层水头损失,,=,30,cm,,,,,,

,长柄滤头水头损失,,=,20,cm,,,,,,

,,△H,=,50,cm,0.5,m,,,,

,"为保证滤池正常过滤时池内的液面高出滤料层,水封井出水堰顶标高与滤料层相同。",,,,,,,,,,

,设水封井堰底板比滤池底板低0.3m,,,,,,,,,,

,出水堰高,H=0.3+H1+H2+H3,,2.75,m,,,,,,

,每组滤池过滤水量,Q,=,418.4100418,m³/h,,,,,,

,,,=,0.116225012,m³/s,,,,,,

,设水封井正方形，边长,L,=,1.5,m,,,,,,

,"所以水封井出水堰上水头由矩形堰的流量公式

Q=1.84b

",,,,,,,,,,

,水封高,h,=,0.121039469,m,,,,,,

,反冲完毕滤池液面比滤料层高,H,=,0.621039469,m,,,,,,

三、反冲洗管渠系统,,,,,,,,,,,

,"②长柄滤头固定板下的气水室高度为0.70～0.90,其中冲洗时形成的气垫层厚度为0.10～0.15m.",,,,,,,,,,

,③向长柄滤头固定板下气水室配气的出口应该紧贴滤头固定板的底面，由配水干管向气水室配水的支管出口应该紧贴池底。,,,,,,,,,,

,④长柄滤头配气系统的滤帽缝隙与滤池过滤面积之比为1/80，每平方米的滤头数量为49～64个。,,,,,,,,,,

,⑤冲洗水和空气同时通过长柄滤头的水头损失按产品的实测资料确定。,,,,,,,,,,

,⑥向长柄滤头配水配气系统气水室配气的干管的进口流速为5m/s左右；配气支管或孔口流速为10m/s左右。配水干管进口流速为1.5m/s左右；,,,,,,,,,,

,配水支管或孔口流速1-1.5m/s。,,,,,,,,,,

1、反洗水量计算,,,,,,,,,,,

,反洗水水量,Q1,=,209.2050209,L/s,,,,,,

,,,=,753.1380753,m³/h,0.209205021,m³/s,,,,

,"V型滤池反冲洗时,表面扫洗同时进行,其流量:",,,,,,,,,,

,,Q2,=,75.31380753,L/s,,,,,,

,,,=,271.1297071,m³/h,0.075313808,m³/s,,,,

2、反冲洗配水断面,,,,,,,,,,,

,配水干管进口流速,v1,=,1.5,m/s,,,,,,

,配水干管的截面积,s1,=,0.139470014,㎡,,,,,,

,干管管径,D1,=,0.421507779,m,,,,,,

,取干管管径,,=,450,mm,,,,,,

,校核流速,v',=,1.316065241,m/s,,,,,,

,"反冲洗水由反冲洗配水干管输至气水分配渠,由气水分配渠底侧的布水方孔配水的滤池底部布水区,",,,,,,,,,,

,反冲洗水通过配水方孔的流速按反冲洗配水支管的流速取值,,,,,,,,,,

,则配水支管方孔流速,v2,=,1.316065241,m/s,,一般取值1.0～1.5m/s,,,,

,方孔总面积,s2,=,0.1589625,㎡,,,,,,

,设方孔数量,n,=,30,个,,,,,,

,单个方孔边长,L,=,0.072792513,m,,,,,,

3、反冲洗气量,,,,,,,,,,,

,反洗气量,Q2,=,627.6150628,L/s,,,,,,

,,,=,2259.414226,m³/h,0.627615063,m³/s,,,,

,配气干管进口流速,v1,=,5,m/s,,,,,,

,配水干管的截面积,s1,=,0.125523013,㎡,,,,,,

,干管管径,D1,=,0.39987739,m,,,,,,

,取干管管径,,=,400,mm,0.2,m,,,,

,校核流速,v',=,4.996935213,m/s,,,,,,

,"反冲洗用空气有反冲洗配气干管输送至气水分配渠,由气水分配渠两侧的布气小孔配气到滤池底部布水区,布气小孔紧贴滤板下缘,",,,,,,,,,,

,"间距与布水方孔相同,共计30个,反冲洗用空气通过配气小孔的流速按反冲洗配气支管的流速取值",,,,,,,,,,

,则配水支管方孔流速,v2,=,10,m/s,,,,,,

,配气小孔总面积,s2,=,0.062761506,㎡,,,,,,

,设小孔数量,n,=,30,个,,,,,,

,单个小孔面积,S,=,0.00209205,㎡,,,,,,

,单个小孔直径,,=,0.051623949,m,,,,,,

4、气水分配渠断面设计,,,,,,,,,,,

,气水分配渠的断面设计按气水同时反冲洗的情况设计,,,,,,,,,,

,气水同时反冲洗时反冲洗水的流量:,,,,,,,,,,

,,Q1,=,167.3640167,L/s,0.167364017,m³/s,,,,

,气水同时反冲洗时反冲洗用空气的流量:,,,,,,,,,,

,,Q2,=,627.6150628,L/s,0.627615063,m³/s,,,,

,气水分配渠面积,s,=,0.25277,㎡,,,,,,

四、滤池管渠设计,,,,,,,,,,,

,a气水分配渠,,,,,,,,,,

,起端宽：,0.4,m,,,起端高：,1,m,,,

,末端宽：,0.4,m,,,末端高：,0.7,m,,,

,起端截面积：,0.4,m2,,,末端截面积：,0.28,m2,,,

,,,,,,末端所需最小截面积：,0.008425667,m2,<末端截面积0.4,,

,b排水集水槽,,,,,高出滤料层顶面：,0.5,m,,,

,起端槽高：,1.95,m,,,末端槽高:,2.25,m,,,

,底坡i：,0.025,,,,,,,,,

五、进水总渠设计,,,,,,,,,,,

,"滤池分为两组,当一格检修，一格反洗时，每组进水总渠过水流量按强制过滤流量设计,流速0.8～1.2m/s,则单格强制过滤流量",,,,,,,,,,

,,Q,=,557.8800558,m³/h,0.154966682,m³/s,,,,

,流速,v,=,1,m/s,,,,,,

,过流面积,s,=,0.154966682,㎡,,,,,,

,过流边长,L,=,0.393658078,m,,,,,,

,取渠宽,L,=,0.4,m,,,,,,

1、每座滤池的进水孔:,,,,,,,,,,,

,"每座滤池由进水侧壁开三个进水孔,进水总渠的浑水通过这三个进水孔进入滤池,两侧进水孔孔口在反冲洗时关闭,中间进水孔",,,,,,,,,,

,"孔口设手动调节闸板,在反冲洗时不关闭,供给反冲洗表扫用水,调节闸门的开启度,使其在反冲洗时的进水量等于表扫水用水量：",,,,,,,,,,

,"孔口面积按口淹没出流公式:Q=0.8A计算,因为是淹没流A=1，其总面积按滤池强制过滤水量计,孔口两侧水位差取0.10m,则孔口总面积",,,,,,,,,,

,A孔=Q/（0.8A）,,,,,,,,,,

,,A孔,=,0.138363109,㎡,,,,,,

,中间面积按照表面扫水量设计,,,,,,,,,,

,,A中孔,=,A孔×(Q表水/Q强),,,,,,,

,,,=,0.067244471,㎡,,,,,,

,孔口宽,B中孔,=,0.24,m,,,,,,

,孔口高,H中孔,=,0.280185296,m,,,,,,

,"两侧孔口设闸门.采用橡胶囊充气阀,每个侧孔面孔：",,,,,,,,,,

,,A侧,=,0.035559319,㎡,,,,,,

,孔口宽,B侧孔,=,0.4,m,,,,,,

,孔口高,H侧孔,=,0.088898298,m,,,,,,

2、每座滤池宽顶堰,,,,,,,,,,,

,"为了保证进水稳定性,进水总渠引来的浑水经过宽顶堰进入每座滤池内的配水渠，在经滤池内的配水渠分配到两侧的V形槽，",,,,,,,,,,

,宽顶堰宽b,b,＝,3.486750349,m,,,,,,

,宽顶堰与进水渠平行设置，与进水总渠侧壁相距0.5m，堰上水头由矩形堰的流量公式Q＝得：,,,,,,,,,,

,,h,=,0.083560258,m,,,,,,

3、每座滤池配水渠,,,,,,,,,,,

,进入每座滤池的混水经过宽顶堰溢流进配水渠，由配水渠两侧的进水孔进入滤池内的V形槽滤池配水,,,,,,,,,,

,渠宽,b,=,0.3,m,,,,,,

,渠高,h,=,1,m,,,,,,

,当渠内水深H=0.30m时，流速（进来的混水由分配渠中段向渠两侧进水孔流去，每侧流量为,,,,,,,,,,

,渠内水深,H,=,0.3,m,,,,,,

,,V,=,0.860926012,m/s,,0.8～1.2m/s,,,,

4、V型槽设计,,,,,,,,,,,

,取扫洗孔平均断面上的过孔流速v,,=,2,m/s,,,,,,

,孔口流量系数,μ,=,0.97,,,,,,,

,V型槽内水深,h,=,,,,,,,,

,,,=,0.210393436,m,,,,,,

,取V型槽超高,h,=,0.1,m,,,,,,

,槽高,b,=,0.310393436,m,,,,,,

,槽宽,x,=,b*tan40°+0.12,,,,,,,

,,,=,0.38026387,m,,,,,,

,设扫洗孔内径,d,=,0.025,m,,,,,,

,单孔流量,Q,=,Q=0.8A,,,,,,,

,,,=,0.000797047,m³/s,,,,,,

,设扫洗孔间距为a,,=,0.79704674,L/s,,,,,,

,沿长度方向一共有,L/a,个孔,,,,,,,,

,V型滤槽至中间排水槽的宽度,b,=,1.363111305,m,,,,,,

,,a,=,0.324847826,m,,,,,,

,取扫洗孔为,d25@350,,,,,,,,,

（4）冲冼水的供给,,,,,,,,,,,

a管路水头损失Δh1,,,选用冲冼水泵供水,,,,,,,,

管长总计,60,m,,,沿程水头损失Δh'f,0.2526,m,0.00421,,,

90度弯头个数：,5,个,,,90度弯头长度换算系数：,3,,系数0.6,,,

闸阀个数：,3,个,,,闸阀长度换算系数：,0.18,,系数0.06,,,

等径三通：,3,个,,,等径三通长度换算系数：,4.5,,系数1.5,,,

,,,,,阻力系数总计К：,7.68,,,,,

Δh'j,0.678672086,m,,,管路水头损失Δh'1,0.931272086,m,,,,

b清水池最低水位与排水堰顶高差H0,,,,,,,,,,,

H0,5,m,,,,,,,,,

c滤池配水系统水头损失Δh'2,,,,,,,,,,,

气水分配渠内水面高h反水,0.317925,m,,,水力半径R反水,0.122768741,m,,,,

水力坡降i反渠,0.004797237,,,,气水分配干渠水头损失Δh反水,0.05756684,m,,,,

配水方孔水头损失Δh方孔,0.11664,m,,,反冼水经过滤头水头损失Δh滤,0.22,m,查手册,,,

气水冲时气水比n,3.75,,,,长柄滤头中的水流速度v柄,0.32,m/s,说明6,,,

通过滤头时水头损失Δh增：,0.2878254,m,,,滤池配水系统水头损失Δh'2,0.9423904,m,,,,

d砂滤层水头损失Δh'3,,,,,,,,,,,

滤料容重,2.65,t/m3,,,滤料膨胀前的孔隙率m0,0.41,,,,,

水的容重,1,t/m3,,,滤料层膨胀前的厚度H3,1.2,m,,,,

滤料层水头损失Δh'3,1.1682,m,,,富余水头Δh'4,1.5,m,,,,

反冲冼水泵的最小扬程：,9.541862486,m,,,,,,,,,

,,,,,