Perbaikan desain tungku hemat energi untuk produsen keumamah di Kota Banda Aceh (Design improvement of energy-efficient stove for keumamah producers in Banda Aceh)

ABSTRAKPengabdian kepada masyarakat (PKM) ini bertujuan mengidentifikasi masalah dan memberikan solusi pada tahap perebusan ikan tongkol sebelum dikeringkan menjadi keumamah. Mitra PKM selama ini menggunakan tungku terbuka yang pembakarannya tidak sempurna sehingga membutuhkan banyak biomassa kayu. Pembakaran dengan tungku terbuka ini menghasilkan banyak asap, jelaga, dan gas-gas polutan. Akibatnya pembelian kayu bakar menjadi belanja bahan terbesar setelah ikan dan berdampak mengurangi margin keuntungan pengusaha. Gas-gas polutan dan asap serta partikel sisa pembakaran berdampak negatif kepada kesehatan pengusaha, pekerja, kualitas, kenyamanan dan ketentraman lingkungan di sekitar tempat usaha. Solusi yang diberikan kepada kedua mitra adalah desain khusus dan pembuatan tungku hemat energi yang menerapkan teknologi tepat guna dengan pengurangan konsumsi biomasa kayu sampai 33% serta meminimalkan asap dan gas-gas polutan. Penggunaan tungku hemat energi ini dapat mengurangi pengeluaran untuk biomasa kayu, perbaikan kenyamanan dan ketentraman lingkungan sekitar usaha serta meningkatkan kesejahteraan pengusaha keumamah. Disamping itu, kualitas keumamah, daya saing, dan perluasan lapangan kerja bagi masyarakat sekitar juga meningkat dan memberikan efek multiplying bagi pertumbuhan ekonomi di sekitar lokasi usaha.Kata kunci: tungku hemat energi, keumamah; biomasa kayu, energi terbarukan ABSTRACTThis community service (PKM) aims at identifying problems and providing solutions for keumamah producers, particularly at the stage of fish boiling prior to the drying of keumamah. PKM partners have been using open stoves with incomplete combustion, thus requiring a lot of wooden biomass. Combustion with this open furnace produces a lot of smoke, soot and pollutant gases. As the results, the purchase of firewood is the biggest material spending after fish and has an impact on reducing the profit margins of producers. Furthermore, pollutant gases and smoke and combustion particles have a negative impact on the health of employers, workers, quality and comfort as well as the environment around and in the production site. The solution given to the two partners is the specially designed and manufactured energy-efficient stoves that include appropriate feature to reduce wooden biomass consumption by up to 33% and minimize smoke and pollutant gases. The use of energy-efficient stoves can reduce expenses on wood biomass, improve comfort and peace of the environment around the business location and improve the welfare of the producers. In addition, the quality of the public life, competitiveness and expansion of employment opportunities for the surrounding community also increase and provide a multiplying effect for economic growth around the business location.Keywords: energy-saving stove, keumamah, wooden biomass, renewable energy

Morphology and elemental analysis of freshly emitted particles from packed-bed domestic coal combustion

This study was conducted in a laboratory-controlled environment to analyse the physical properties and elemental composition of coal combustion particles in a brazier. Particles were sampled ~1 m above the stove, using a partector. Particles were collected on gold transmission electron microscopy (TEM) grids, and polycarbonate filters for TEM and inductively coupled plasma mass spectrometry (ICP-MS) analysis, respectively. Particles for elemental analysis were collected on a 37 µm polycarbonate filter, and the exhaust was drawn in using a GilAir Plus pump. During sampling, a 2.5 µm cyclone was attached to the sampling cassette to isolate larger particles. Combustion particles emitted during the early stage of combustion were single organic spherical particles with similar characteristics to tarballs. As the combustion progressed, the particle diameter gradually decreased (from 109 nm), and the morphology changed to smaller particles (to 34.3 nm). The particles formed accretion chain structures, showing evidence of agglomeration. Furthermore, a fluffy microstructure, resembling the formation of soot, was formed in the post flaming phase. In the char-burning phase, an irregular structure of semi-spherical particles was formed, showing evidence of mineral particles infused with small carbonaceous particles. Similarly, with the findings of previous studies, the present research also observed organic spherical particles similar to tarballs. Given that during the ignition phase there was a simultaneous burning of wood as kindling and coal, the provenance of these particle emissions can be attributed to both coal and wood.

Morphology and Elemental Analysis of Freshly Emitted Particles from Packed-bed Domestic Coal Combustion

This study was conducted in a laboratory-controlled environment aiming at studying the physical properties and elemental composition of coal combustion particles in a brazier. Particles were sampled ~1 m above the stove using a partector, where particles were collected on gold Transmission Electron Microscopy (TEM) grids and polycarbonate filters for TEM and inductively coupled plasma mass spectrometry (ICP-MS) analysis, respectively. Particles for elemental analysis collected on a 37 µm polycarbonate filters whereby a Gillian pump was used to draw in air. During sampling, a 2.5 µm cyclone was attached to the sampling cassette to isolate larger particles. The results have shown that combustion particles emitted during the early stage of combustion where single spherical particles with a diameter of around 450 nm. As the combustion progresses, the particle diameter gradually decreases and the morphology changes to accretion chain and fluffy bead structure for the flaming and char-burning phase, respectively.

Two Dimensional Axisymmetric Simulation Analysis of Vegetation Combustion Particles Movement in Flame Gap under DC Voltage

In recent years, extreme high temperature weather occurs frequently, which easily causes forest fires. The forest fire is prone to the trip accident of the transmission line. Previous studies show that charged combustion particles cause electric field distortion in the gap below the transmission line, and trigger discharges near the conductor area. The motion and distribution characteristics of combustion particles in the gap have an important influence on the discharge characteristics. Therefore, the size and morphology of combustion particles are analyzed through combustion experiments with typical vegetation. The combustion particles are mainly affected by the air drag force, electric field force and gravity. The interaction and influence of temperature, fluid, electric field and the multi-physical field of particle motion are comprehensively analyzed. A two dimensional (2D) axisymmetric simulation model is established by simplifying the flame region. According to the heat release rate of vegetation flame combustion, the fluid temperature and velocity are calculated. Combined with the fluid field and electric field, the forces on particles and movement are calculated. The results can provide a basis for the analysis of the electric field distortion, and further study the discharge mechanism of the gap under the condition of vegetation flame.