Fighting against POLLUTION to Save Environment

  • Fighting against POLLUTION to Save Environment

Fighting against POLLUTION to Save Environment

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List of Publications of Dr. Dilip Boralkar

Experience in implementation of environmental standards in lead industry. Proc. workshop Lead Pollution Control & Monitoring, ILZIC & CPCB, New Delhi, August, 1995:

Appeared in “Ecology in Practice” a collection of Articles for Prof. S.B. Chaphekar’s festschrift volume on his 60th birthday edited by C.S. Latto of Prof. S.B. Chaphekar Felicitation Committee,Bombay.

D. B. BORALKAR
Central Laboratory, Maharashtra Pollution Control Board
CIDCO Bhavan, CBD Belapur, New Bombay-400 614.

4.3 Particulate matter, kg/batch

Charge = 6258
Slag = 2600
Crude = 2800
Bag filter dust = 520
U tube, settler = 313
Emission = 25
Corresponding Concentration = 418.72 mg/m3

Observed concentration from actual stack monitoring is 26.48 mg/m3. Hence it is concluded that the venturi scrubber is having an efficiency of 93% for particulate removal.

5. Ambient air quality prediction

An attempt was made to predict the ambient air quality in terms of lead. The predicted quality based on Gaussian plume model and a set of assumptions is shown in figure 1. This is a rough estimate and needs to be validated. The assumptions are:

  1. All furnaces are in operation at the same time.
  2. Emissions from all stacks are same and a single stack with combined emission and a height of 30 m is taken into account.
  3. Meteorological conditions are same throughout the day.

Stability class was neutral with wind velocity of 2 m/sec.

Results of actual ambient air quality measurements in terms of lead are presented in Table 2 and predicted ambient air quality in terms of lead in the

Table 3 : Results of Stack (Point Source) Emission Monitoring at Secondary Lead Smelting and Refining Industries In Small Scale Sector

Stack Emission Monitoring Data at Secondary Lead Smelting and Refining Industries
Parameter No.1 No.2 No.3 No.4 No.5 No.6 No.7
7.1.95 18.6.94 31.5.94 8.12.94 20.7.94 20.12.94 20.7.94 21.12.94 18.7.95 15.9.94 18.8.94 18.7.94
Stack Height, m 30 24 24 26 26 20 20 26 26 30 30 26
Stack area Sq. m 0.385 0.113 0.113 0.234 0.11 0.159 0.16 0.159 0.159 0.107 0.375 0.11
Flue Gas Temp. °C 80 89 140 20 130 90 90 205 80 95 110 130
Exit Velocity m/s 2.74 2.24 5.13 1.82 1.42 1.51 1.7 1.8 2.06 1.59 2.71 1.42
Gas Quantity Nm3/hr 3206 758 2027 928 416 865 817 620 950 504 850 416
Particulate matter mg/Nm3 1111 574 3042 753 1887 2888 1369 2534 944 1099 671 1887
Lead Emission mg/Nm3 181 197 97 135 274 373 126 317 532 223 103 274

Note: Emission limit: Particulate matter: 150 mg/Nm3, Lead: 10 mg/Nm3

C. Related to Workplace Environment
  • Ventilation in the main workshops is to be improved by exhaust fans and collected air passes through filters.
  • Provision of a water sprinkler system in the raw material storage area is to be considered for increasing its capacity.
  • Floor slabs for the entire raw material handling area and main workshop wherein smelting and refining operations are carried out to be provided to minimise indoor dust level.
D. Related to Recovery/Reuse
  • Zinc sulphate recovery from bag house dust is possible and may be attempted expeditiously.
  • Elemental sulphur can be obtained from SO2 emissions by reaction with potassium citrate and citric acid and this may be examined.
  • Rotary furnace slag can be used for manufacture of ferrosilicate cement by cement manufacturing units.
  • Tall trees like Ashoka along the compound wall near the flue dust storage area may be planted.
  • A.C. Roofing arrangements with louver type ventilations for the flue dust storage area to avoid dust emissions to the neighbouring residential area during loading operations, vehicular movement and due to wind.
ACKNOWLEDGEMENTS

Useful suggestions and technical support provided by Dr. K.R. Ranganathan and his students from Indian Institute of Technology, Bombay, is gratefully acknowledged.

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