Analysis on foulants shows that: the elements (except for C, H and O) in foulants formed during evaporating alkaline wheat straw black liquor are Si, Ca , K, Na, Mg and Al; Si and Ca account for about 36% of the weigh...Analysis on foulants shows that: the elements (except for C, H and O) in foulants formed during evaporating alkaline wheat straw black liquor are Si, Ca , K, Na, Mg and Al; Si and Ca account for about 36% of the weight of foulants; The organic ingredients amout to about 20% of the foulant; Rhodesite (Ca,K,Na)8Si16O40·11H2O is the main composition in foulants. The fouling mechanism of wheat black liquor is quite different from that of soft/hard wood black liquor, because the content of Si inside wheat straw black liquor is much more than that of soft/hard wood black liquor. Complex chemical reactions occur when evaporating wheat straw black liquor. The author considers that colloid H2SiO3 plays an important role in the process. The minerals produced by reactions between H2SiO3, with anion charges and positive ions, such as Ca2+, K+, Na+, etc. Further investigation on the process should be done.The fractal theory is used to analyze the fouling geometric texture. The fractal dimension values D of foulants are also calculated.展开更多
In this paper, a new type of retention system of PEO/cofactor retention system is introduced, the cofactors used are phenol-formaldehyde resin, wheat straw alkaline lignin and its derivatives such as hydroxymethylated...In this paper, a new type of retention system of PEO/cofactor retention system is introduced, the cofactors used are phenol-formaldehyde resin, wheat straw alkaline lignin and its derivatives such as hydroxymethylated lignin, sulfited lignin and lignin-based phenol-formaldehyde resin. The first pass retention of newsprint slurry and the properties of handsheet are improved by using the system. The results indicate that a new application field for lignin has been exploited.展开更多
文摘Analysis on foulants shows that: the elements (except for C, H and O) in foulants formed during evaporating alkaline wheat straw black liquor are Si, Ca , K, Na, Mg and Al; Si and Ca account for about 36% of the weight of foulants; The organic ingredients amout to about 20% of the foulant; Rhodesite (Ca,K,Na)8Si16O40·11H2O is the main composition in foulants. The fouling mechanism of wheat black liquor is quite different from that of soft/hard wood black liquor, because the content of Si inside wheat straw black liquor is much more than that of soft/hard wood black liquor. Complex chemical reactions occur when evaporating wheat straw black liquor. The author considers that colloid H2SiO3 plays an important role in the process. The minerals produced by reactions between H2SiO3, with anion charges and positive ions, such as Ca2+, K+, Na+, etc. Further investigation on the process should be done.The fractal theory is used to analyze the fouling geometric texture. The fractal dimension values D of foulants are also calculated.
文摘In this paper, a new type of retention system of PEO/cofactor retention system is introduced, the cofactors used are phenol-formaldehyde resin, wheat straw alkaline lignin and its derivatives such as hydroxymethylated lignin, sulfited lignin and lignin-based phenol-formaldehyde resin. The first pass retention of newsprint slurry and the properties of handsheet are improved by using the system. The results indicate that a new application field for lignin has been exploited.
