Pengendalian Mutu Produk Semen Melalui Pendekatan Statistical Quality Control (SQC) (Studi Kasus Di PT. Semen Baturaja)

PT. Semen Baturaja (Persero) tbk merupakan perusahaan yang bergerak dibidang produksi semen di sumatera selatan. Produk yang diproduksi berupa produk semen OPC dan PCC. Suatu produk tentunya tidak terlepas dari permasalahan produk tidak sesuai standar kualitas produk. Tujuan dari penelitian ini adalah untuk mengetahui upaya pengendalian kualitas dan faktor – faktor apa saja yang menyebabkan ketidaksesuaian kualitas produk yang diproduksi oleh PT. Semen Baturaja, pengukuran produk tidak sesuai standar berdasarkan lima parameter pengukuran kualitas, yakni Blaine, Residu 45µm, SO3, FCaO dan LOI, dengan menggunakan metode Statistical Quality Control, diagram Pareto dan Diagram sebab akibat, diperoleh hasil analisis yakni, parameter Residu 45µm dan Blaine memiliki jumlah ketidaksesuaian yang paling dominan yakni 71,9% dan 23,7%, yang berarti Penyebab terbesar ketidaksesuaian produk adalah mesin Tube Mill, dimana volume ball mill <80% yang mengakibatkan proses penggilingan material menjadi tidak optimal

Research on the effect of the grooving of mill rolls of the reeling tube mill on the wear of the elongating mandrel

By means of numerical simulation the influence of the geometry of calibers of mill rolls on the wear of the elongating mandrel is determined. The type of the grooving of mill rolls of a continuous three roll reeling mill, which reduces the wear of the elongating mandrel during the rolling, is determined.

Improvement of enzymatic digestibility of wood by a sequence of optimized milling procedures with final vibratory tube mills for the amorphization of cellulose

A three-stage wood milling process was investigated leading to coarse, fine and amorphization of milled wood (MW) as a pretreatment for enzymatic wood hydrolysis. An eccentric vibratory tube mill (EVTM) and a spring suspended vibratory tube mill (SSVTM) were found to be suitable for wood cellulose amorphization. Both methods gave rise to highly digestible and amorphous wood powders amenable to enzymatic hydrolysis. The SSVTM had superior energy efficiency. The resulting MW afforded a 70% sugar yield via enzymatic hydrolysis and the total energy consumption was around 1.5 kWh kg−1oven-dried wood (odW) for all three milling stages. In contrast, EVTM consumed 17 kWh kg−1odW energy. Accordingly, SSVTM has a high potential for preparing wood for enzymatic hydrolysis.

Mill Steam Inerting System Review and Performance Validation

NFPA 85, Chapter 9.5.4 states “A pulverizer that is tripped under load shall be inerted and maintained under an inert atmosphere until confirmation that no burning or smoldering fuel exists in the pulverizer or the fuel is removed”. Pulverizer systems with the potential for a resident inventory of combustible material upon trip must be designed and equipped with an inerting system that is capable of maintaining an inert atmosphere to meet this requirement. Proper design of the inerting system and operating procedure, integrated with the mill operation during start-up, shut down and emergency trip is critical for safe mill operation. This paper presents a mill steam inerting system review and performance validation. The technology has been applied to ball tube mill systems at Hoosier Energy’s Merom Generating Station. A testing technique, used to validate performance of the steam inerting system at this generating plant, is described. It quantifies the compliance of the steam inerting system to meet NFPA requirements during start-up and shut down of the pulverizer. This type of operation is considered to be the most difficult for inerting as the primary air is flowing through the system. The developed testing approach can be applied to evaluate the performance of either existing or newly installed steam inerting systems. The validation technology, developed based on a ball tube mill system, can be readily applied on other types of mill systems, since the steam inerting principle is the same and inerting system requirements are similar, regardless of different mill types.

Analysis and Modification on Blockage Problem of BBD Double Inlet and Outlet Tube Mill Separator

This article analysis the relationship between BBD inlet and outlet tube mill separator blockage and the boiler's safety-economy, finds out the cause of the separator blockage, puts forward the corresponding reform scheme, then the retrofit scheme after implementing separator blockage problem.