Page 227 - Materials Chemistry, Second Edition

210 Practical Design Calculations for Groundwater and Soil Remediation

Solution:
(a) DRE of benzene:

500 0.04−
=
DRE = 99.992% > 99.99%
500
(b) DRE of phenol:

300 0.04−
DRE = 99.987% < 99.99%
=
300

(c) DRE of PCE:

200 0.01−
=
DRE = 99.995% > 99.99%
200
The combustion unit is not in compliance because DRE of phenol
is less than 99.99%.

Example 5.33: Determine the Generation of Hydrogen Chloride

For the trial burn mentioned in Example 5.32, if all the chlorine in the feed
stream is converted to hydrogen chloride, estimate the hydrogen chloride
flow rate prior to emission control.

Solution:
(a) MW of PCE (C Cl ) = (12)(2) + (35.5)(4) = 166
4
2
Molar flow rate of PCE = (200,000 g/h) ÷ (166 g/mole) = 1,205
moles/h

(b) Molar flow rate of HCl = molar flow rate of Cl = 2 × molar flow
rate of PCE
= 2 × 1,205 = 2,410 moles/h

(c) MW of HCl = 1 + 35.5 = 36.5
Mass flow rate of HCl = (2,410 moles/h) × (36.5 g/mole) = 97,965 g/h
= 97.97 kg/h

Discussion:
The general RCRA requirement for HCl emission is ≤1.8 kg/h or >99%
reduction. In this case, a removal of HCl is required.