Table 1.

Chemical and morphological properties of paper sludge.

Properties	Value	Tappi test method
Acid-insoluble lignin*	16.6	T 222 om-2224
Acid-soluble lignin	0.39	UM 25025
Total inorganic, %	47.4	T 211 om-2226
Total organic, %	53.6	T 211 om-2226
Dry matter, %	56.4	T 550 om-2227
pH	7.1	T 252 om-2228
Fiber length, mm	0.79	T 271 om-2229
Fiber width, µm	22.7	T 271 om-2229
Aspect ratio	59.8	Calculated from T 271 om-2229

*Klason lignin.