3.1 Resources of Natural Fibre Plants
3.2 Agricultural Residues in China
3.3 Bamboo
3.4 Resource and Output of Reeds
3.5 The Production and Demand for Bagasse
3.6 The Resources of Hemp and Flax Fibre
3.7 Waste paper
The four main fibre material resources of non-wood plants are the following: natural non-wood fibre resources; bamboo; agricultural residues; and recycled fibre (waste paper).
Non-wood fibre resources other than bamboo, trattan, reeds and those of agricultural residue origin are called natural non wood fibre resources. Although there is some cultivated areas for industrial purpose, most of them are wild.
Roots, stems, leaf and bark for different wild fibre plants contain fibre which can be used for spinning fabric, making paper and others. Besides fibre use, many branches and canes of fibre plants can be used for weaving goods of daily life and handicraft. Fibre plants are also widely used for industrial raw materials.
Grass and timber fibres have for long been used for making paper. Since the Qin and Han dynasty, flax has been used for spinning grass cloth. At present, wild fibre and other fibres generating different cotton, flax and polyester fibres have been spun into many new types of cloth, which opened a new way for the modern textile industry. Wild fibre, besides being used for making ordinary paper, can be also used for making high-grade paper, wrapping paper, advertisement paper and wall paper for building decorations and for making artificial silk, cotton powder, no-smoking powder, plastic, spray paint and other industrial chemical products.
According to inventory, more than 1,000 species of fibre plants have been developed or tried, of which about 100 species of fibre plants are used widely for weaving and paper-making. The following are some grasses and shrubs for paper production: Typha latifolia L., Deyeuxia angustifolia (Kom.) Chang, Eulaliopsis binata (Retz.) C.E. Hubbard, Miscanthus sinensis andorss, Iris ensata Thunb, Pteroceltis tatarinowii Maxim, Lespedeza bicolor Turcz, and Hibiscus cannabinus.
The bark of Pteroceltis tatarinowii is raw material of Xuan paper which is the famous traditional handwriting paper in China.
3.2.1 Agriculture Harvesting Residues
3.2.2 Agricultural Processing Residues
The agriculture residues include both those from harvesting and from agricultural processing. It was estimated that the total area of main crops is 114.888 million ha. and the total of residues is 419.875 million tons in 1994. The fibre contents of agriculture residues are about 35 %-55%3.
3 These numbers give an average gross residues yield of 3.65 tons/ha of residues, of which the fibre content is 1.28-2.01 tons/ha (Editor).
The agricultural harvesting residues are the crop stalks which include: the straws of wheat, rice, cotton, maize, beans, tobacco, sunflower, other grain and rape etc. In 1994, the total production of these residues in the whole country was about 386.02 million tons. With the fibre content in these agricultural residues being between 35-55 % (near to fibre contents of broad-leaved tree species), they are not only a most important potential fibre material resource, but also good substitutes for wood.
The wastes after agricultural products are processed are called Agricultural Processing Residues. They include bagasse, hemp and flax residue, rice husk and peanut crust. It is easy to collect and transport this type of raw material because it is already mainly stocked in the factories. The output of agriculture processing residuals was 22.3 million tonnes in 1994 (or nearly 6 % of harvest residue in quantity).
Table 9 - The Areas of Main Crops and the Output of Main Agriculture Residues in 1994
|
Area |
Output of Residues |
|||
'000 ha |
% |
'000 tons |
% |
||
Wheat straw |
28,981 |
25.2 |
108,679 |
25.9 |
|
Rice |
Rice straw |
30,172 |
26.3 |
113,145 |
26.9 |
Rice hull |
- |
- |
13,578 |
3.2 |
|
Cotton stalk |
5,528 |
4.8 |
24,876 |
6.4 |
|
Maize stalk |
21,152 |
18.4 |
95,184 |
22.7 |
|
Sorghum stalk |
1,368 |
1.2 |
6,156 |
1.5 |
|
Sunflower stalk |
804 |
0.7 |
3,618 |
0.9 |
|
Tobacco stalk |
1,489 |
1.3 |
4,467 |
1.1 |
|
Millet straw |
1,672 |
1.5 |
5,016 |
1.2 |
|
Bagasse |
1,056 |
0.9 |
4,752 |
1.1 |
|
Hemp |
371 |
0.3 |
1,113 |
0.3 |
|
Peanut hull |
3,776 |
3.3 |
283 |
0.7 |
|
Beans straw |
12,736 |
11.1 |
19,104 |
4.5 |
|
Rape straw |
5,783 |
5.0 |
17,355 |
4.1 |
|
Total |
114,888 |
100 |
419,875 |
100 |
The annual production of pulp from rice straw and wheat straw was about 8,516 thousand tons which was 47.69% of total pulp production. The rate of pulp-produced from rice and wheat straw is 39.9%. From 1990 to 1994 the annual production of rice and wheat straw was 10,3693 thousand tons and the production of rice and wheat straw pulp was 8,000 thousand tons with the consumption of straw raw material 20,512 thousand tons which is 19.7% of total rice and wheat straw. The utilization of rice and wheat straw is concentrated in some province such as Henan, Hebei, and Hubei etc. Because of heavy pollution and transportation constraints, the development of rice and wheat straw for paper will be limited; by 2000, the proportion of rice and wheat straw pulp is expected to be only 27%.
Table 10 - The Resource Changes Over the Years (103 ha, 103 tons)
|
Rice |
Wheat |
Cotton |
||||||
Area |
Straw output |
Area |
Straw output |
Area |
Straw output |
||||
103 ha |
Index |
103 t |
103 ha |
Index |
103 t |
103 ha |
Index |
103 t |
|
1900 |
33755.3 |
100 |
62447.3 |
28844.4 |
100 |
43266.6 |
4920.2 |
100 |
12300.6 |
1985 |
32070.1 |
95 |
59329.7 |
29218.1 |
101 |
43827.1 |
5140.3 |
104 |
12850.25 |
1988 |
31987.4 |
95 |
59176.7 |
28784.7 |
100 |
43177.0 |
5534.7 |
112 |
13836.83 |
1990 |
32700.4 |
97 |
60495.8 |
29841.4 |
103 |
44762.1 |
5588.1 |
114 |
13970.25 |
1991 |
33064.4 |
98 |
61169.1 |
30753.2 |
107 |
46129.8 |
6538.5 |
133 |
16346.25 |
1992 |
32090.2 |
95 |
59367.0 |
30495.8 |
106 |
45743.7 |
6835.0 |
139 |
17087.5 |
1993 |
30355.0 |
90 |
56156.8 |
30235.0 |
105 |
45352.5 |
6285.3 |
128 |
15713.42 |
1994 |
30171.5 |
89 |
55817.3 |
28980.7 |
100 |
43471.1 |
5528.0 |
112 |
13820.07 |
1995 |
|
|
|
|
|
|
|
|
|
China is one of the key native homes and sources of modern distribution for bamboos in the world; where there are more than 500 bamboo species covering over 7 million hectares. Bamboo is one of the important raw materials for industry and handicraft in south China. According to statistics, the output and value of bamboo products in 1992 were as follows: 200 thousand tons of machine-made bamboo pulp, 0.169 billion pieces of bamboo farm tools; the output value of bamboo woven products was 79.3 million yuan RMB. The bamboo pulp production in China is maintained at the level of about 250,000 tons annually (see Table 14).
Table 11 - Bamboo Resource in China
Province |
Bamboo Area |
Moso Bamboo (Phyllostachys heterocycla var. Pubescens (10 thousand ha) |
Other Species |
SiChuan |
74.00 |
1.90 |
72.10 |
Fujian |
62.79 |
59.20 |
3.59 |
Hunan |
61.20 |
57.10 |
4.10 |
Zhejing |
59.82 |
54.40 |
5.42 |
Jiangxi |
53.40 |
52.93 |
0.47 |
Guangdong |
31.8 |
10.81 |
20.99 |
Anhui |
17.63 |
15.17 |
2.46 |
Taiwan |
17.56 |
0.33 |
17.23 |
Guangxi |
16.32 |
9.51 |
6.81 |
Shannxi |
13.45 |
0.33 |
13.42 |
Yunnan |
10.20 |
0.33 |
10.17 |
Hubei |
8.75 |
6.22 |
2.53 |
Hainan |
5.39 |
- |
5.39 |
Guizhou |
4.43 |
2.00 |
2.43 |
Jiangsu |
4.00 |
2.00 |
2.00 |
Henan |
1.67 |
0.20 |
1.47 |
Shandong |
0.18 |
0.01 |
0.17 |
Shanxi |
0.02 |
- |
0.02 |
TOTAL |
442.61 |
271.84 (61%) |
170.77 (39%) |
Table 12 - The Change of Bamboo Resource (103 ha, 103 tons)
Year |
Total resource |
Moso bamboo |
Other bamboo |
||||||||||
Area |
Stand Volume |
Area |
Stand Volume |
Area |
Stand Volume |
||||||||
Individual plants |
Weigh |
||||||||||||
103 ha |
Index |
103 ha |
Index |
103 ha |
Index |
103 ha |
Index |
103 ha |
Index |
103 ha |
Index |
||
1977-1981 |
3199.6 |
100 |
64943 |
100 |
2496.6 |
100 |
35796 |
53695 |
100 |
703 |
100 |
11248 |
100 |
1983-1988 |
3546.3 |
111 |
76288 |
117 |
2526.4 |
101 |
39978 |
59970 |
112 |
1019.9 |
145 |
16318 |
145 |
1989-1993 |
3790.8 |
118 |
95731 |
147 |
2602.3 |
104 |
499537 |
74931 |
139 |
1189.5 |
169 |
20800 |
185 |
Table 13 - The change of bamboo production (103 tons)
|
Total production |
Moso bamboo production |
Other bamboo |
|
Weight |
Index |
|||
1985 |
4,891 |
100 |
3,764 |
1,127 |
1986 |
5,279 |
108 |
4,091 |
1,188 |
1987 |
5,771 |
118 |
4,518 |
1,253 |
1988 |
6,654 |
136 |
5,318 |
1,336 |
1989 |
6,513 |
133 |
5,062 |
1,451 |
1990 |
6,443 |
132 |
4,981 |
1,462 |
1991 |
7,108 |
145 |
5,529 |
1,579 |
1992 |
8,103 |
166 |
6,511 |
1,592 |
1993 |
9,030 |
185 |
7,380 |
1,650 |
1994 |
9,265 |
189 |
7,505 |
1,760 |
Table 14 - The Output and consumption of Bamboo Pulp from 1985 to 1995 (103 tons)
Year |
1985 |
1986 |
1987 |
1988 |
1989 |
1990 |
1991 |
1992 |
1993 |
1994 |
1995 |
Pulp Output |
128 |
139 |
144 |
157 |
156 |
164 |
170 |
180 |
160 |
190 |
350 |
Bamboo Consumption* |
348 |
417 |
432 |
471 |
468 |
492 |
510 |
540 |
480 |
570 |
1,050 |
* Raw material equivalent.
The main bamboo species are Phyllostachys pubescens, Bambusa textilis, Dendrocalamus latiflorus, Neosinocalamus affinis, Pseudosasa amabilis. Ph. Nuda, Ph. Glauca, Ph. Viridis, Ph. Bambusoides, and Ph. Iridenscens etc.
The research and development of the bamboo-based panels in China started in 1970s and the first phase product was bamboo mat plywood. After several decades, with research on the structure, physical, mechanical and chemical properties of bamboo, a number of other bamboo products were developed of which the main products put into production are: bamboo strip plywood, bamboo curtain laminated board, paper-overlaid bamboo curtain plywood, bamboo particleboard, rotary bamboo thin veneer, and bamboo-timber composite board. There are also some products that have been manufactured successfully, but not officially put into production such as bamboo fibreboard, cement-bonded bamboo particleboard, bamboo-plaster particleboard etc. Data on these products are in Table 15.
Table 15 - The production of bamboo-based panels in China*
|
Annual production (m3) |
No. of mills |
Price in the market (yuan/m3) |
Value (103 yuan) |
Bamboo mat plywood |
90,000 |
90 |
2,800 |
252,000 |
Bamboo curtain plywood |
40,000 |
30 |
2,800 |
112,000 |
Bamboo strip plywood |
30,000 |
24 |
4,000 |
120,000 |
Bamboo strip laminated plywood |
25,000 |
20 |
2,800 |
70,000 |
Bamboo based particleboard |
15,000 |
20 |
1,200 |
37,000 |
Bamboo floorboard |
20,000 |
30 |
3,700 |
74,000 |
Bamboo based molded board |
5,000 |
10 |
- |
- |
Total |
225,000 |
224 |
- |
665,000 |
* the figures are from Prof. Zhu Huanming from the Chinese Academy of Forestry.
About 1,700 years ago, Chinese people began to manufacture bamboo-based paper. The traditional method is: tenderize bamboo, pulverize, lime, solarize, bleach, dry the paper. Bamboos of Phyllostachys, Pleioblastus, Bambusa, Dendrocalamus, Neosinocalamus, Chimonobambusa etc. varieties are used as raw material for paper-making; 1 year-old bamboo stems are used as raw material in the traditional methods while 3-5 year-old bamboos are used in mechanical pulp. Different paper products can be produced depending upon proportion of bamboo pulp. From 1991 to 1994, the annual bamboo pulp was only 175 thousand tons that is only 0.95% of total pulp in China with the bamboo consumption of 525 thousand tons (i.e. 3 tons bamboo per ton of pulp). In 1995, the production of bamboo pulp increased to 350 thousand tons that is 1.54% of total pulp.
Table 16 - The Bamboo Production from 1985 to 1995 (103 tons)
Year |
The Production of Bamboo Pulp |
Bamboo consumption |
1985 |
1,280 |
3,480 |
1986 |
1,390 |
4,170 |
1987 |
1,440 |
4,320 |
1988 |
1,570 |
4,710 |
1989 |
1,560 |
4,650 |
1990 |
1,640 |
4,920 |
1991 |
1,700 |
5,100 |
1992 |
1,800 |
5,400 |
1993 |
1,600 |
4,800 |
1994 |
1,900 |
5,700 |
1995 |
3,500 |
10,500 |
The annual bamboo consumption for paper is about 1.3-1.6 million tons which is 12%-15% of total bamboo production.
Reeds are an important raw material for paper and panel industries. The planted area increases year by year. From 1991 to 1995, annual outputs of reeds pulp was 920 thousand tons which constituted 5.15% of total pulp output and was about five times the quantity of bamboo pulp. In 1995, total reeds output was 2,560 thousand tons and 2,375 tons of them was used for pulp4. According the statistics, reed plantations totalling 854 thousand ha for paper and panel industries were established, of which by 1995, 510 thousand ha, with output of 1950 thousand tons were put into production. At the present, the average yield per unit is low at only 1.65 ton per ha in 66% of the total area. In Hunan province, however, the yield per ha reached 11 tons which shows the great potential to increase total output of reeds in China. Table 17 shows steadily increasing area of reeds and faster expansion of the area used. Output has been growing much faster than area of reeds.
4 A yield of about 920,000 tons of pulp from this volume suggests a conversion ratio of nearly 3.6 tons of reeds per ton of pulp (editor).
Table 17 - The Outline of Main Reeds Sources in 11 Provinces of China (103 ha, 103 tons)
Year |
Total area |
Area of used reeds |
Output |
Supply |
||
Area |
Index |
Area |
Index |
|||
1985 |
791.33 |
100 |
442.67 |
1,360.0 |
1,190.0 |
100 |
1987 |
806.89 |
102 |
471.41 |
1,473.7 |
1,232.4 |
103 |
1988 |
809.84 |
102 |
483.30 |
1,625.8 |
1,409.3 |
118 |
1989 |
811.87 |
103 |
488.68 |
1,659.7 |
1,469.6 |
123 |
1990 |
849.67 |
107 |
481.65 |
1,662.3 |
1,352.2 |
114 |
1991 |
849.44 |
107 |
485.51 |
1,693.0 |
1,364.9 |
115 |
1992 |
850.00 |
107 |
488.00 |
1,732.0 |
1,420.3 |
119 |
1995 |
854.00 |
108 |
510.00 |
1,950.0 |
1,657.0 |
139 |
Bagasse is the fibre residue left after extraction of sugar from sugarcane; 1.13 tons of bagasse is produced for each 21 tons of sugar. The yield of pulp produced from bagasse is 39%. From 1984 to 1994, the area of sugarcane expanded from 965 thousand ha to 1,065 thousand ha and the production of sugarcane also increased from 51.549 to 60.926 million tons. About 80% of total sugarcane was used to process sugar. In 1992, the area of sugarcane was 1,246 thousand ha and the production was 70,311 thousand tons with the production of bagasse 7,419 thousand tons.
Table 18 gives the data of output of bagasse and bagasse pulp, showing that about a sixth of total bagasse output is pulped.
Table 18 - The Output of Bagasse and Bagasse Pulp5 in the Past Years (103 ha, 103 tons)
5 Approximate ratios of sugar case to bagasse are 10-13 tons cane per ton bagasse; the ratio for pulp is around 2.6 tons bagasse per ton pulp (editor).
Year |
the area of cultivation |
Yield of sugarcane |
Output of bagasse |
Supply for pulp |
Output of bagasse pulp |
||||
Sugar Area |
Index |
Quantity |
Index |
Weight |
% total bagasse |
Area |
Index |
||
1985 |
965 |
100 |
51,549 |
100 |
4,090.6 |
628.7 |
15 |
245.2 |
100 |
1986 |
950 |
98 |
50,219 |
97 |
4,915.3 |
658.2 |
13 |
256.6 |
105 |
1987 |
859 |
89 |
47,363 |
92 |
4,836.4 |
658.9 |
14 |
256.9 |
105 |
1988 |
924 |
96 |
49,064 |
95 |
4,237.5 |
676.9 |
16 |
263.9 |
108 |
1989 |
959 |
99 |
48,795 |
95 |
4,316.6 |
705.1 |
16 |
275.0 |
112 |
1990 |
1,009 |
105 |
57,620 |
112 |
5,356.2 |
717.9 |
13 |
280.0 |
114 |
1991 |
1,164 |
121 |
67,898 |
132 |
5,491.8 |
743.5 |
14 |
290.0 |
118 |
1992 |
1,246 |
129 |
73,011 |
142 |
7,419.6 |
871.8 |
12 |
340.0 |
139 |
1993 |
1,088 |
113 |
64,194 |
124 |
7,073.8 |
769.2 |
11 |
300.0 |
122 |
1994 |
1,057 |
109 |
60,927 |
118 |
5,621.7 |
897.4 |
16 |
350.0 |
143 |
Hemp and flax fibre is traditionally used for gunny bags and gunny cloth. In recent years, with the development of substitutes (artificial fibre), sales of hemp and flax have decreased; this gives an opportunity to use them as raw material for paper. The main source of hemp fibre is kenaf. There are some paper mills used kenaf as raw material for paper but this is relatively difficult to find. Waste gunnysacks are the main source of pulp made from hemp and flax fibre. The cultivation area of kenaf is influenced heavily by the flax industry. Kenaf could be planted in most of China except Tibet. The production of kenaf in Anhui and Henan province is higher than other provinces in China. Table 19 shows that the area under kenaf had, by 1994, declined to less than a fifth of that in 1985; kenaf output decreased to match during this period.
Table 19 - The Cultivation Areas and Output of Kenaf (103 ha, 103 tons)
|
1985 |
1986 |
1987 |
1988 |
1989 |
1990 |
1991 |
1992 |
1993 |
1994 |
Area |
991 |
345 |
272 |
277 |
286 |
300 |
270 |
277 |
274 |
175.7 |
Output |
2,060 |
710 |
569 |
540 |
660 |
726 |
513 |
619 |
672 |
354.9 |
The utilization of waste paper is receiving more attention in the world owing to the desire for greater environment protection. The consumption of pulp from waster paper increased from 4,050 thousand tons to 7,600 thousand tons from 1991 to 1995.
Table 20 - The Annual Consumption of Waste Paper and Percentage of Total Pulp Consumption from 1991 to 1995 ('000 tons)
|
|
Total waste paper pulp consumption |
Imported part |
1991 |
Consumption |
4,050 |
620 |
Percentage* |
27.0 |
4.13 |
|
1992 |
Consumption |
4,900 |
630 |
Percentage |
28.0 |
4.80 |
|
1993 |
Consumption |
5,400 |
480 |
Percentage |
28.47 |
2.6 |
|
1994 |
Consumption |
6,300 |
590 |
Percentage |
29.17 |
2.71 |
|
1995 |
Consumption |
7,600 |
770 |
Percentage |
33.51 |
3.39 |
* % in paper-making fibre mix.
In 1993, the recycling, utilization, import, and export of waste paper were 4,461, 5,249, 604, and 16 thousand tons respectively. From Table 20, it may be noted that the imported share of waste paper pulp which was about 15% in 1991 declined to only 9% by 1993 and 10% by 1995; the rest was domestic waste paper pulp.