Inner Mongolia Heli Chemical Fiber (Group) Co., Ltd.
Waste gas source:
Workshop one contains two 1.5‑meter 12K pre-oxidation & carbonization production lines and a 4.2‑meter 24K pre-oxidation & carbonization production line.
Workshop two contains two 4.2-meter 24K pre-oxidation & carbonization production lines.
Workshop three contains two 4.2-meter 50K dual-layer pre-oxidation & carbonization production lines.
Waste gas composition:
The waste-gas components of each kind of production line and their concentrations are given in the following tables.
Tab. 1 Reference values for waste‑gas concentrations of the 1.5‑meter‑width production line (12K)
|
Component |
Unit |
Pre‑oxidation furnace |
Low‑temperature carbonization furnace |
High‑temperature carbonization furnace |
|
HCN |
kg/h |
7.68-13.82 |
18.43-33.17 |
6.85-12.32 |
|
NH3 |
kg/h |
3.29-5.92 |
6.14-11.06 |
2.28-4.11 |
|
CO |
kg/h |
2.19-3.95 |
5.84-10.50 |
2.17-3.90 |
|
CH4 |
kg/h |
1.1-1.97 |
3.07-5.53 |
1.14-2.05 |
Tab. 2 Reference values for waste‑gas concentrations of the 4.2‑meter‑width production line (24K)
|
Component |
Unit |
Pre‑oxidation furnace |
Low‑temperature carbonization furnace |
High‑temperature carbonization furnace |
|
HCN |
kg/h |
39.00-54.00 |
93.60-129.61 |
37.44-48.14 |
|
NH3 |
kg/h |
16.72-23.14 |
31.20-43.20 |
12.48-16.05 |
|
CO |
kg/h |
11.14-15.43 |
29.64-41.04 |
11.86-15.24 |
|
CH4 |
kg/h |
5.57-7.71 |
15.60-21.60 |
6.24-8.02 |
Tab. 3 Reference values for waste‑gas concentrations of the 4.2‑meter‑width production line (50K)
|
Component |
Unit |
Pre‑oxidation furnace |
Low‑temperature carbonization furnace |
High‑temperature carbonization furnace |
|
HCN |
kg/h |
63.00-105.61 |
151.21-253.45 |
56.16-94.14 |
|
NH3 |
kg/h |
27.00-45.26 |
50.40-84.48 |
18.72-31.38 |
|
CO |
kg/h |
18.00-30.17 |
47.88-80.26 |
17.78-29.81 |
|
CH4 |
kg/h |
9.00-15.09 |
25.20-42.24 |
9.36-15.69 |
Treatment process:
Generally, exhaust gas from the pre-oxidation furnaces and all the waste gas captured by hoods are directed to RTOs, while the high-temperature exhaust gas from the carbonization furnaces is directed to TOs.
In a workshop, for each kind of production line, there is always a spare RTO serving as a backup. There are no standby TOs.
RTO specification:
The capacities of RTOs and TOs are determined by the types of production lines. RTOs installed for 1.5-meter 12K production lines have a capacity of 30,000 m3/h, while TOs installed for these production lines have a capacity of 1,150 m3/h.
RTOs for 4.2-meter 24K production lines have a capacity of 90,000 m3/h, and the capacity of TOs for these production lines is 5,700 m3/h.
Finally, RTOs for 4.2-meter 50K production lines have a capacity of 110,000 m3/h, while TOs for these production lines have a capacity of 8,000 m3/h.
Emission limits:
The emission limits are listed in the following table.
Tab. 4 Emission Limits
|
No. |
Waste‑gas Component |
Emission Limit, mg/m³ |
|
1 |
NMHC |
120 |
|
2 |
NOx |
100 |
|
3 |
HCN |
1.9 |