Environmental Knowledge Management - Recent Advances and Issues in Environmental Science - page 58

and resources. The benefits of a zero waste policy are that it reduces operation costs,
increases profit and complies with environmental regulations. The CSC continuously
creates new technology to reduce waste or transfer it into useful resources through
continuous improvement in the manufacturing process, consistently moving towards
a zero waste system. With the improvements in technology and investment in the R
& D Department over the past two decades, CSC has accomplished its missions and
goals gradually.
Its performance in reducing residues and recycling will be shown in the Table 4
and Figure 7.

Figure 7. Percent of sludge recycled at CSC since 1999 [42].

Table 4. By-products of process residues in 2004 [44].

Generation
(10,000 tons)

%oftotal
residues

Type of residue Description

BF slag By-products of BF after smelting or raw materials 303.9 49.0

BOF slag By-products of the basic oxygen furnace (BOF) after refming of steel 128.2 20.6

De-S slag By-products of the hot metal desulfurizing process 36.8 5.9

Dust Particulates collected from de-dusting system 34.1 5.5

Sludge Solid cakes or mud from wastewater treatment after condensing and

dehydrating

44.8 7.2

Mill scale Rust of steel products or semi-products 29.4 4.7

Spent refractory Used refractory from high temperature process 4.0 0.6

Civil refractory Residual soil, concrete, etc. 19.8 3.2

Limestone cake Filter cake from limestone washing water 5.0 0.8

Other Waste oil, waste packaging materials, refuse, etc. 15.5 2.5

Total 621.5 100