STUDI EKSPERIMENTAL TERHADAP KARAKTERISTIK POROUS-VENTURI MICRO-BUBBLE GENERATOR DENGAN SUDUT INLET 30 DERAJAT DAN SUDUT OUTLET 12 DERAJAT

RIFQI TAUFIK AL HAKIM, Prof. Dr. Ir. Indarto, DEA.

2017 | Skripsi | S1 TEKNIK MESIN

Karena meningkatnya populasi dunia, dan meningkatnya permintaan air bersih, dibutuhkan sebuah sistem waste treatment yang ekonomis, dan dapat diterapkan secara massal. Micro-bubble adalah metode waste treatment yang menjadi sorotan akhir-akhir ini, karena sederhana dan dapat diandalkan. Maka dari itu, sangat penting untuk mengetahui karakteristik dari micro-bubble generator, mesin yang menghasilkan micro-bubble, untuk dibahas dalam penelitian ini. Dalam penelitian ini, dilakukan studi eksperimental terhadap karakteristik micro-bubble generator tipe porous-venturi dengan sudut inlet 30 derajat sudut outlet 12 derajat. Penelitian dilakukan dengan cara menganalisis pengaruh beberapa variasi debit gas dan debit air terhadap parameter-parameter tertentu yaitu: hydraulic power, bubble generating efficiency, pressure loss, koefisien perpindahan massa volumetris, dan distribusi diameter bubble. Dari penelitian ini ditemukan bahwa hydraulic power meningkat seiring peningkatan debit air. Dengan debit air (QL=30 lpm) menghasilkan hydraulic power yang paling rendah. Sedangkan debit gas mempunyai efek yang kecil terhadap hydraulic power. Bubble generating efficiency terendah ditemukan pada debit QL=80 lpm dan QG=0,2 lpm dan tertinggi pada QL=30 lpm dan QG=1 lpm. Lalu, koefisien perpindahan massa volumetris meningkat seiring meningkatnya debit gas. Kemudian pada analisis distribusi diameter bubble ditemukan bahwa mean bubble diameter turun seiring penurunan debit air, dan meningkat seiring peningkatan debit gas. Dimana mean bubble diameter terendah terdapat pada QL=80 lpm dan QG=0,2 lpm.

Because of the rising world population, also increases with clean water demand, therefore it is needed to develop a new and economical water treatment system, which can easily be applied to the masses. Micro-bubble is a water treatment method that is trending recently, because of its simplicity and reliability. Therefore, in this research, the characteristics of venturi type micro-bubble generator with a porous pipe with an inlet angle of 30 degree and outlet angle of 12 degree was studied. To study the characteristics, an experimental study was conducted on effects of multiple parameters to a variety of liquid and gas flow rate combination. These parameters are: hydraulic power, bubble generating efficiency, pressure loss, volumetric mass transfer coefficient, and bubble size distribution. After the study has been conducted, it has been found that hydraulic power increases as the liquid flow rate increases, whereas at QL=30 lpm produces the lowest hydraulic power, and the increase of gas flow rate had little to no effect to the hydraulic power. Lowest bubble generating efficiency is found at QL=80 lpm and QG=0,2 lpm. Highest was found at QL=30 lpm dan QG=1 lpm. Then, the volumetric mass transfer coefficient was found increasing as the gas flow rate increases. In the bubble size distribution analysis was found that mean bubble diameter declines as the water flow rate declines, and the gas flow rate increases. Whereas the lowest mean bubble diameter was found at QL=80 lpm and QG=0,2 lpm.

Kata Kunci : Micro-bubble, Micro-bubble generator, MBG, characterization, characteristics, DO (Dissolved Oxygen), venturi, karakterisasi, karakteristik