สถานการณ์ปัจจุบันและแนวโน้มในการใช้เยื่อกระดาษ สำหรับผลิตกระดาษเหนียวในประเทศไทย / สมศักดิ์ เผ่าโภคสถิตย์ = Current situation of and future demand for pulp for kraft paper production in Thailand / Somsak Phaopoksathit
Kraft paper is a type of industrial paper, and one which is used more than any other types of paper. Kraft paper industry therefore has a significant impact on the country’s ecomony. The Bureau of Industrial Standard Product, The Ministry of Industry has established five classification of kraft paper, namely, a. multi wall bag paper b. wet strength paper c. wrapping or single wall bag paper d. kraft liner board e. ribbed kraft paper. Large quantities of pulp are used in producing Kraft paper, and large quantities of raw material are used for producing pulp. This factor, together with the fact that the smaller factories producing kraft paper in Thailand have importing large quantities of waste paper for use as raw material in pulp production when other types of raw materials could be found locally, present interesting proposition for a study to be made of pulp for kraft paper production in Thailand. This study is limited to making a study of pulp as used in producing kraft paper most of which is unbleached kraft pulp containing a suitable mixture of short and long fibers, Data have been collected from various sources including government agencies, state enterprise, private organizations and people connected with or dealing in pulp for kraft paper production in Thailand, as well as from books, journals and other reference materials. The data were then analised and classified according to the requirement of the study. The result of the study indicates that there are many types of raw material which are suitable for producing the kind of pulp used in the production of kraft paper, for example, kenaf, bamboo, pinewood, bagasse, rice straw and Burmese grass etc. However, the result of the study also indicates that the quantity of pulp production is comparatively low, with only one factory using bagasse to produce pulp for kraft paper, and the remainder using pulp from waste paper obtained locally and from abroad. Pulp from various types of raw material can be used in the production of kraft paper. However, due consideration should be given to the quality of pulp as follows :- a. Pulp from pinewood. This is the long fiber pulp. The quantity of pinewood in Thailand is however rather limited, and reforestation take considerable time. Pulp from pinewood can substitute all the imported long fiver pulp. b. Pulp from kenaf. This is 70% short fiver and 30% long fiber pulp. Pulp from kenaf can be a partial substitution for imported pulp, and is in sufficient quantity fro producing the required amount of pulp. c. Pulp from bamboo. This is the short fiber pulp which has the same quality as pulp produced from kenaf. There is a large quantity of bamboo in the western part of the country, sufficient for the demand fro use as raw material in producing pulp. d. Pulp from bagasse. This is the short fiber pulp. The quantity of bagasse depends upon the sugarcane cultivation or the sugar industry. If the sugar industry is declining, or a large quantity of bagasse is used for boilers, the quantity of bagasse may not meet the demand. e. Pulp from rice straw. This is a very short fiber pulp. The quantity depends upon the country’s rice crops and is restricted by transportation cost which could result in high cost production where the distance is far. f. Pulp from Burmese grass. This is a combination of short fiber pulp and bagasse pulp. Burmese grass is weed to farmers and therefore its destruction could result in insufficient quantity to meet the demand. g. Pulp from waste paper. This is short fiber pulp. the quantity of waste paper depends upon the quantity of paper used annualy. Medium quality kraft paper normally contains a mixture of approximately 60% long fiber pulp and 40% short fiber pulp viz., production of one ton of kraft paper requires 1.07 ton of pulp which uses 0.642 ton of long fiber and 0.428 ton of short fiber pulp. The thesis concludes that pinewood is the only type of pulp which can substitute imported pulp, and that waste paper available from local should be used in the production of short fiber pulp, which is tantamount to economical use of natural resources. As for the demand of pulp besides existing waste paper, pulp from kenaf should be the best type of raw material because of its good quality and its availability quantity sufficient for the demand. Bamboo and bagasse are second to kenaf for their short period of cultivations after which they can be used as raw materials. Kenaf, bamboo and bagasse are therefore the three types of raw material which are worthly for promotion as raw material in pulp production.
