Ditemukan 6 dokumen yang sesuai dengan query
Diansyah Putri FH
"Salah satu metode pengolahan limbah cair secara biologis adalah dengan menyisihkan substansi-substansi organik yang terdapat dalam limbah cair tersebut dengan bantuan mikroorganisme. Mikroorganisme yang dimanfaatkan bisa merupakan mikroorganisme aerob ataupun mikroorganisme anaerob. Fokus dalam penelitian ini adalah proses biologis yang menggunakan mikroorganisme aerob. Untuk menjaga kelangsungan hidup mikroorganisme ini, dilakukan proses aerasi, yakni melarutkan oksigen kedalam air limbah, dengan alat yang disebut aerator, Alat ini mensuplai oksigen kedalam air limbah, dan melakukan mixing (pengadukan), sehingga terjadi kontak yang memadai antara lumpur yang mengandung mikroorganisme dan bahan organik yang terdapat didalam limbah. Kemudian diendapkan di bak sedimentasi dan ditarik oleh pompa. Pada unit pengolahan yang umum dipakai, aerator dan pompa merupakan dua komponen yang berbeda dan terpisah, sehingga lahan yang dipakai relatif luas dan biaya yang digunakan cukup mahal. Oleh karena itu, diusahakan menggabung keduanya dengan konsep airlift pump. Penggabungan fungsi komponen aeralor dan pompa tersebut telah dilakukan oleh Agus Subiyakto dengan menggunakan konsep airlift pump. Alat ini disebut aeralor pump, dengan komponen utama blower dan baling-baling (rotating blade). Selama 9 tahun alat ini diterapkan di lapangan, ditemukan kendala yaitu tidak efektifnya alat ini jika limbah yang diolah mengandung serat atau debris. Serat (debris) yang terdapat dalam air limbah tersebut menyangkut pada sela baling-baling (rotating blade). Tersangkutnya serat ini menurunkan kinerja alat karena kontak yang terjadi antara permukaan gelembung udara dan air limbah berkurang sehingga suplai oksigen juga berkurang. Karena itu, pada penelitian ini akan dicoba menggantikan rotating blade dengan fixedscrew cylinder. Dari modifikasi ini, dicoba membuat 21 buah alat dengan variasi sudut ulir dan luas kanal, sehingga dapat dibandingkan alat mana yang paling efektif dalam menghasilkan debit optimum dan menaikkan nilai DO air limbah. Dari percobaan yang dilakukan, diambil data debit air dan nilai DO yang dihasilkan, sebagai parameter utama untuk melihat efektivitas ke 21 alat tersebut. Selain itu digunakan rumusan debit yang diturunkan dari rumusan kerja air dan udara, sehinga didapatkan nilai ? yang menggambarkan efisiensi alat dan fraksi udara pada tekanan tertentu. Setelah diamati, ternyata Debit optimum terbesar dihasilkan oleh alat aerator pump 18, dengan diameter kanal 5/8 inch, luas kanal sebesar 0.000197832 m_ dan sudut kanal 60"" , dengan nilai debit yang dihasilkan sebesar 1,4.10
"One of biological waste water treatment methods is by separating organic substances from the waste water with the help of microorganisms. Microorganisms which are used can be either aerob or anaerob. The focus of this research is the biological process using aerob microorganisms. Aeration process is undertaken to keep these microorganisms alive, by dissolving oxygen into the waste water using a device called aerator. The device is supplying oxygen into the waste water and doing a mixing process so that there is a sufficient contact between the mud, which contain microorganisms and the organic substances which in the waste water. Then, it will be settled in sedimentation tank and sucked out by the pump. In generally used treatment unit, aerator and pump are two separated and different components, so that it needs a relatively big area and expensive cost. That's why we tried to unite these two components with using airlift pump concept. The uniting of these two components function has been done by Agus Subiyakto with using airlift pump concept. The device is called aerator pump, with its main components are blower and rotating blades. During 9 years application in the field, he encountered a problem that the device is not being effective when the waste water contain fibers. The fibers that in the waste water are stuck among the rotating blades and it decrease the device's working ability because contacts between the surface of air bubbles and the waste water is decreasing so that the oxygen supply is cecreasing as well. To overcome the problem, we tried to replace rotating blade with fixedsrew cylinder. From this modification we tried to make 21 devices with variation in screw's angle and cross section area so that we can compare which is the most effective and resulting optimum discharge and increasing Dissolved Oxygen (DO) amount of the waste water. Data of water discharge and DO amount produced are taken from tests. These data are the main parameters to see the effectiveness of those 21 devices. Beside of it, discharge formula which a result from differentiating the air and water energy formula is used so that we can get ? which shows the effectiveness of the device and air fraction under certain pressure. After being observed, it turned out that the biggest optimum discharge is from the aerator pump device 18, with screw's diameter of 5/8 inch, cross section area of 0,000197832 m_ angle of 60_ and discharge amount of 1,4.10-5 m_s. The biggest DO amount which increasing is produced by the aerator pump device 6, with screw's diameter of 5/16 inch, angle of 70"" and the increasing of DO amount of 5,48 mg/L. And based on the ? amount, then the device which produces the highest dissolved air fraction and efficiency is the aerator pump 7, with srew's diameter of 5/16 inch, angle of 75_ and ? amount of 0.0318923168."
Depok: Fakultas Teknik Universitas Indonesia, 2004
S35094
UI - Skripsi Membership Universitas Indonesia Library
Beveridge, Ross
"This book provides a detailed analysis of the controversial privatisation of the Berlin Water Company (BWB) in 1999. As with other cases of privatisation around the world, the city’s government argued there was no alternative in a context of public debts and economic restructuring. Drawing on post-structuralist theory, the analysis presented here steps outside the parameters of this neat, straightforward explanation. It problematises the ‘hard facts’ upon which the decision was apparently made, presenting instead an account in which facts can be political constructions shaped by normative assumptions and political strategies. A politics of inevitability in 1990s Berlin is revealed, one characterised by depoliticisation, expert-dominated policy processes and centred upon the perceived necessities of urban governance in the global economy. It is an account in which global and local dynamics mix, where the interplay between the general and the specific, between neoliberalism and politicking, and between globalisation and local actors characterise the discussion."
Wiesbaden: [Springer, ], 2012
e20399515
eBooks Universitas Indonesia Library
