Design of V notch for discharge measurement

 

 

Installation Guidelines for V notch

 

 

 

 

• Use a 2mm Thick Mild Steel plate to make the V notch. Make a 90^o V

• Water surface downstream of the weir should be at least 6 cm below the bottom of the V to allow a free flowing waterfall.

• The bottom of the "V" only needs to be 10 cm (=P) above the bottom of the upstream channel,
• the approach channel (=B) only needs to be 2 ft. wide,

• Head (h) should be measured at a distance of at least 4h upstream of the weir.

 

Q = 4.28 C tan(θ/2)( h+k)^5/2

 

where

Q = flow rate (cfs)

C= Discharge Coefficient, C=0.578 for 90^o V notch

θ = v-notch angle ( 90^o

h = head on the weir (ft)

k = Head Correction factor(Ft)

• k (ft.) = 0.0144902648 - 0.00033955535 Ø + 3.29819003x10^-6 ز - 1.06215442x10^-8 س
  where Ø is the V notch angle in degrees ( 90^o

 

 

Source: ENVO PROJECTS. NEW DELHI-25 9899300371, 9810004529

Saleem Asraf Syed Imdaadullah
Mobile : 9899300371
311/22,Zakir Nagar,New Delhi-110025
email: saleemasraf@gmail.com
BLOG: http://saleemindia.blogspot.com

latest technology dye waste water treatment ZERO discharge

Effluents are segregated into dye bath wastewater and wash water and treatment is effected

accordingly.

Wash water is collected in holding tanks and pumped to primary treatment unit (lime and

ferrous sulfate slurries are flash-mixed with effluent and allowed for settling). Following

primary treatment the effluent is carried to pressure sand filter, iron removal filter, ion

exchange filter and reverse osmosis (RO) system. Double stage RO system (each with six

membranes) with spiral wound membrane is in operation. Pump pressure is maintained in

the range of 21.2–28.2 kg/cm

2

. Rejects of first RO is sent to second RO and the final reject

(20%) is sent to MEE. Condensate water is recycled in the cleaning operations. Outlet with

100 g/L solid content is allowed for solar evaporation and the combined permeate is used in

the process. Dye bath water is collected in a separate tank and are subject to nanofiltration

after following pre-filtration. Total reject of about 30% is sent for multi effect evaporation

and solar evaporation systems. The permeate is used for preparation of dye bath solution

Saleem Asraf Syed Imdaadullah
Mobile : 9899300371
311/22,Zakir Nagar,New Delhi-110025
email: saleemasraf@gmail.com
BLOG: http://saleemindia.blogspot.com

Magnesium chloride wastewater treatment

Magnesium chloride, as compared to alum and polyaluminium chloride (PAC) is a less commonly used coagulant in the field of wastewater treatment, with a cost in between alum and PAC. It has been used in this study as a coagulant to investigate the effectiveness in the chemical precipitation method for the removal of colouring matters. The colour concentration of dye solutions was measured by visible spectrophotometry. Parameters such as the effect of pH, the effect of coagulant and coagulant aid dosages and the effect of different coagulants have been studied. The results show that MgCl₂ is capable of removing more than 90% of the colouring material at a pH of 11 and a dose of 4 g MgCl₂/l of dye solution. MgCl₂ is shown to be more effective in removing reactive dye than alum and PAC in terms of settling time and amount of alkalinity required. Optimal operating conditions such as pH value, coagulant dose and effect of polyelectrolyte have been determined. Wastewaters of a dyeing and printing mill on different days have been treated by MgCl₂ aqueous solution in bench scale. The treatment of the industrial waste has shown a reduction of 88% in COD and 95% of suspended solids.

Author Keywords: chemical coagulation; colour reduction; textile waste effluent

Saleem Asraf Syed Imdaadullah
Mobile : 9899300371
311/22,Zakir Nagar,New Delhi-110025
email: saleemasraf@gmail.com
BLOG: http://saleemindia.blogspot.com