24 SEP 2021  |  CLOSED ON: 31 MAR 2022  |  REWARD: INR 10,00,000/-
Reward money is paid in exchange of legally acquiring the solution, implementing it to solve the problem and meeting the success criteria. Milestones for paying the reward money would depend upon the complexity of challenge and maturity of the proposed solution, which would be discussed with the solver as soon as the proposed solution is selected by us.
Rewarded

31 MAR 2022

INR 10,00,000/-

We are seeking cost-effective treatment methodologies in the effluent treatment plant for the neutralization of acidic effluents, to generate treated water of < 200 ppm hardness and sludge of < 30% moisture.

Challenge Details

The effluent treatment plant (ETP) of a wire manufacturing industry handles 18,000 m3/month of effluent, collected from various units as represented in Figure 1. The constituents of the overall effluent are represented in Table 1. The overall process flow is represented in Figure 2.

Table 1: Constituents of the incoming effluent

Test

Result

Unit of measure

pH

1.97

---

Total Solid

3810.00

mg/lit

Chloride

2600.00

mg/lit

Hardness as MgCO3

25.95

mg/lit

Sulphate as SO4

281.80

mg/lit

Phosphate as PO4

16.12

mg/lit

Calcium (as Ca)

34.53

mg/lit

Magnesium (as Mg)

7.50

mg/lit

Total Iron (Fe)

419.30

mg/lit

 

The treatment process utilizes Lime for the neutralization of effluents. The current consumption rate of lime is 5.5kg/m3 of effluent. The use of lime results in 2 subsequent problems:

  1. High Hardness (>2500 ppm) of the treated water - The desired hardness of treated water is 200 ppm. High hardness impacts the performance of the downstream reverse osmosis (RO) plant. For the reduction of hardness, Soda ash treatment is required, which increases the operational cost significantly.
  2. Higher quantities of Red sludge generation (>200 MT/month) - Red sludge (Figure 3) consists mainly of iron, calcium, and magnesium. The sludge contains around 75% to 85% moisture, which increases the sludge disposal cost. The desired moisture content in Red sludge is < 30%.

We are seeking cost-effective treatment methodologies in the effluent treatment plant which can meet the following requirements:

  • The alternative treatment methodology should be able to neutralize the acidic effluent.
  • The hardness of treated water should be < 200 ppm.
  • Moisture content in red sludge should be < 30%.
  • The sludge generation should be reduced by 50%.
  • The overall operational cost of the effluent treatment plant should be reduced.

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