Judul: Penghilangan emisi odor H2S dan NH3 dari proses pengomposan limbah padat industri pulp dan kertas dengan menggunakan biofilter
Abstrak: A semipilot biofilter system was conducted to removal odor emission from sludge composting from pulp and paper industry. The main mal-odorous gases were identified as hydrogen sulfide (H2S) and amonia (NH3). Simulation composting process emitted H2S about 0.186 ppm and NH3 about 0.778 ppm for 103 ppm days operation. The biofilter media was peat at 0.75 m depth and 3 inchi diameter. Four treatments peat of biofilter were: native peat (control column), peat inoculated with Thiobncillz~ss p. (T column), peat inoculated with Nitrosomonas sp. N column) and peat inoculated with Thiobacillus sp. and Nitrosomonas sp.
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Judul: Penghilangan Polutan Gas Amoniak Dengan Biofilter Skala Pilot. Studi Kasus : PTPN VIII Pabrik Karet Cikumpay, Purwakarta, Jawa Barat.
Abstrak: Ammonia gaseous has a great potential to be a pollutant in rubber processing industries. The largest source of pollutant is at condensed latex processing. Therefore, biofilter was applied to remove emission of ammonia gaseous from the process. The objectives of this research were (1) to determine the level of physical and chemical absorption to ammonia sourness in forest soil based packing-bed material mixed with compost and carbonized rice husk, and (2) to determine the performance of biofilter to remove ammonia gaseous at pilot scale. Packing bed materials used were forest soil, bokashi compost and carbonized rice husk. The treatment of K111 was packed with forest soil, bokashi compost and carbonized rice husk with composised by 1:1:1. K112 was 1:1:2, K121 was 1:2:1, and K122 was 1:2:2. Physical and chemical characteristics of packing-bed materials within 5 parameters were obtained at ranked level of K112>K122>K111>K121. Carbonized rice husk influenced on physical - chemical characteristics of packing-bed materials, such as density, total porosity, water filled pore space and maximum capacity of loading, except air filled pore space. Those compositions were applied as packing bed materials to biofilters. Composition treatment of K111, K112, K121, K122 were applied to packing bed materials of B111, B112, B121 and B122. Biofilter were applied on pilot scale with 250 liters volume. For 55 days operation, ammonia pollutant concentrations were fluctuated from 0.18 to 68.66 ppm. Parameters inlet and outlet ammonia concentration, physical and chemical characteristics, population of ammonia oxidation bacteria and biofiltration process were monitored. Maximum removal capacities of B111, B112, B121 and B122 biofilters were 0.97, 1.46, 1.03 and 1.62 g-N/kg dry media. The result of biofiltration performance for 11 parameters showed that B112>B122>B121>B111. The best biofilter was determined by its ability in removing pollutant and the cost of required packing-bed. The price of packing bed materials from the lower prices were B111<B112<B122<B121. The cheapest price of packing bed material was B111, but it wasn’t a good performance of biofiltration. Therefore, B112 which was filled by forest soil, bokashi compost and carbonized rice husk with composition 1:1:2 was the best biofilter performance among them.
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Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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