Karakteristik penurunan kualitas serat dan lembaran Pulp pada dua tahap penggilingan ulang

HADI, Didik Surya, Dr.Ir. Sri Nugroho Marsoem, M.Agr

2007 | Tesis | S2 Ilmu Kehutanan

Kekurangan bahan baku industri pulp dan kertas di Indonesia berusaha diatasi antara lain dengan perluasan HTI, pengembangan hutan rakyat, pemanfaatan serat non kayu serta limbah kertas untuk didaur ulang. Proses penggilingan sebagai komponen utama pada daur ulang kertas berpotensi menurunkan kualitas serat pulp dan lembaran yang dihasilkan, terutama pada pulp kimia. Penelitian ini bertujuan untuk mengetahui karakteristik penurunan kualitas serat dan lembaran akibat proses penggilingan ulang dan mengetahui perbedaan karakteristik tersebut di antara beberapa jenis kayu, yakni mangium, sengon dan tusam. Penelitian menggunakan rancangan acak lengkap secara faktorial, faktor I : jenis kayu (mangium, sengon dan tusam), faktor II : tahap penggilingan (serat primer, giling I, giling ulang I dan giling ulang II). Setiap perlakuan diulang sebanyak 2 kali. Parameter yang diamati : Rendemen dan bilangan kappa, dimensi serat dan nilai turunannya serta sifat kekuatan fisik lembaran (ketahanan sobek, retak dan tarik). Hasil penelitian menunjukkan seluruh parameter yang diamati dipengaruhi secara nyata oleh interaksi faktor jenis kayu dan tahap penggilingan. Kualitas serat dan lembaran tertinggi terdapat pada perlakuan kayu tusam yang berserat panjang pada pulp primer. Mayoritas parameter mengalami penurunan secara kualitas dengan bertambahnya tahap penggilingan. Panjang serat mengalami penurunan pada setiap tahap penggilingan, rata-rata 10,13% untuk mangium, sengon 6,60% dan tusam 12,74%. Diameter serat naik 7,59% untuk mangium, sengon 2,59% dan tusam 3,09%. Diameter lumen naik 6,21% untuk mangium, sengon 1,01% dan tusam 7,63%. Tebal dinding menurun 4,51%, sengon 1,04% dan tusam 5,45%. Bilangan runkel menurun rata-rata setiap tahap turun 7,46 untuk mangium, sengon 11,13% dan tusam 10,61%. Bilangan mulhsteph rata-rata 1,21% untuk mangium, sengon 7,28% dan tusam 6,56%. Daya tenun menurun rata-rata 13,44% untuk mangium, sengon 3,87% dan tusam 13,32%. Bilangan fleksibilitas meningkat rata-rata setiap tahap 0,79% untuk mangium, sengon 3,89% dan tusam 4,13%. Ketahanan sobek menurun rata-rata setiap tahap 22,60% untuk mangium, sengon 15,71% dan tusam 24,82%. Ketahanan retak menurun rata-rata 23,63% untuk mangium, sengon 35,70% dan 32,80% untuk pulp tusam. Ketahanan tarik juga menurun rata-rata 17,69% untuk mangium, sengon 31,36% dan 22,94% untuk tusam.

The lack of raw material in Indonesian pulp and paper industries is tried to be solved by enlarging HTI, developing people forest, exploiting nonwood fiber and recycling wastepaper. Beating process as a fundamental treatment in paper recycling tend to reduce fiber pulp and sheet quality, especially in chemical pulp. The research is aimed to describe the characteristics of fiber pulp and sheet decreasing quality caused by re-beating process. The other purpose is to analyze the difference of their characteristics of some pulpwood raw materials, i.e. mangium, sengon and tusam. The research uses Completely Randomized Design factorially with 2 factors. Factor I : wood species (mangium, sengon and tusam); factor II : the stage of beating (virgin pulp, beating I, re-beating I and re-beating II). Each treatment is repeated twice. The parameters are : rendemen and kappa number, fiber dimension and its derivation value, and physical strength properties of sheet (tear strength, bursting strength and tensile strength). The result shows that all parameters are affected significantly by interaction between pulpwood species and the stage of beating. The highest quality of fiber and sheet is the treatment on virgin pulp of tusam which has long fiber. Most of parameter decrease in quality with twice re-beating. Fiber length decreases in each beating stage at average 10.13% for mangium, sengon 6.60% and tusam 12.74%. Fiber diameter increases 7.59% for mangium, sengon 2.59% and tusam 3.09%. Lumen diameter increases 6.21% for mangium, sengon 1.01% and tusam 7.63%. Wall thickness decreases at average 4.51% for mangium, sengon 1.04% and tusam 5.45%. Runkel ratio decreases in each beating stage at average 7.46% for mangium, sengon 11.13% and tusam 10.61%. Mulhsteph number decreases at average 1.21% for mangium, sengon 7.28% and tusam 6.56%. Felting power decreases 13.44% for mangium, sengon 3.87% and tusam 13.32%. Flexibility ratio increases in each beating stage 0.79% for mangium, sengon 3.89% and tusam 4.13%. Tear strength decreases in each beating stage at average 22.60% for mangium, sengon 15.71% dan tusam 24.82%. Bursting strength decreases 23.63% for mangium, sengon 35.70% and tusam 32.80%. Tensile strength also decreases 17.69% for mangium, sengon 31.36% dan 22.94% for tusam.

Kata Kunci : Pulp,Penggilingan Ulang,Kualitas Serat dan Lembaran, fiber quality, physical strength of sheet, paper recyling, beating stage