Study on an efficiency algorithm for the opening middle tap of steam feed pump

This paper presents a method for calculating the efficiency of steam feed pump, which fills the literature gap in calculating the efficiency of steam feed pump when the middle tap of feed pump is opened. This method has the advantages of convenient measurement and few measurement parameters. Combined with IFCIFC-97 industrial water and steam thermodynamic property model, the efficiency of feed pump can be calculated

ANALISIS PERBANDINGAN KEBUTUHAN ENERGI MENGGUNAKAN BOILER FEED PUMP DAN MOTOR INDUKSI PADA KONDISI START UP (STUDY KASUS: PLTU TANJUNG JATI B UNIT 3)

Kebutuhan energi listrik yang semakin meningkat tidak hanya diikuti dengan peningkatan pasokan energi listrik saja, tetapi harus diikuti dengan pengelolaan energi yang baik dan efisien. Salah satu caranya yaitu dengan mengurangi penggunaan energi sendiri (auxiliary power) pada pembangkit listrik. PLTU Tanjung jati B Unit 3, yang mempunyai 2 Boiler Feed Pump (BFP) dengan penggerak Turbin uap (Turbine Boiler feed Pump atau TBFP) dan 1 buah BFP dengan pengerak Motor Induksi (Motor Boiler feed Pump atau MBFP). Penelitian ini dilakukan perbandingan peralatan tersebut yang bekerja dengan kebutuhan energi paling minimal. Proses pengambilan data dilakukan pada kondisi start up, cold 12 jam, warm 6 jam, hot 2 jam. Dari hasil penelitian menunjukan, untuk kondisi start up cold 12 jam MBFP mempunyai tingkat konsumsi energi 54,8 MWh, sedangkan TBFP hanya mengkonsumsi energy 21,6 Mwh, atau sebesar 60.58 % dari jumlah energi yang digunakan oleh MBFP dan dapat menghemat biaya sebesar Rp 11.487.200,00. artinya TBFP mampu menghemat penggunaan energi 33,2 MWh atau setara 2.980 rumah berlangganan daya listrik PLN 1300 VA, konsumsi daya aktif rata-rata 11,14 kWh/day (33.200 kWh/11,14 kWh = 2980 unit rumah)

Analysis of efficiency of feed pump control by changing rotation of rotor for power plants of various types

The type of power plant feed pump drive is selected in the course of a feasibility study. Domestic experience is based on recommendations that have been obtained in the middle of the last century when fuel was relatively cheap. These recommendations are currently being revised. Manufacturers of technological tools of pumps frequency control offer to install fluid couplings, variable frequency electric drives or drive turbines for power plants of various types. At the same time, they declare the high efficiency of such solutions. But the effect is often calculated based on energy savings indicators for the pump drive without considering changes of the operating modes of other equipment of the power plant. An urgent task is a comprehensive assessment of the effectiveness of the measures under consideration. This assessment should consider the objective parameters and modes of facilities operation, as well as interrelation of power electricity cost for own needs and loads of the basic equipment. To determine the technical effect of application of various methods of frequency control of feed pumps, models are used that are developed on the individual basis for each power plant based on the energy characteristics of the equipment. These models include algorithms for heat and electrical balances. Operational characteristics of the feed pumps and performance assessment are calculated according to the known techniques. Based on a unified methodological approach, the authors have developed mathematical models of condensing power supply units and combined heat and power plants for an initial pressure of 12,8 MPa. These models make it possible to determine the effect of frequency control of feed pumps based on data for real time in operation considering the interrelation of power electricity cost for own needs and loads of the basic equipment. Calculation of index of performance of application of various means of frequency control of feed pump performance have been carried out. It is revealed that to assess the efficiency of application of technological tools of frequency control of feed pumps, it is of decisive importance to consider the experience of equipment load, load schedules, the interrelation of power electricity cost for own needs and loads of the basic equipment. No general recommendations to use certain methods of feed pumps control are applicable, when conducting such an assessment.

Microencapsulation of Lactobacillus rhamnosus ATCC 7469 by spray drying using maltodextrin, whey protein concentrate and trehalose

This study aimed to microencapsulate Lactobacillus rhamnosus ( L. rhamnosus) ATCC 7469 with whey protein concentrate (WPC), maltodextrin and trehalose by spray drying and to assess the impact of microencapsulation on cell viability and the properties of the dried powders. Spray-drying conditions, including inlet air temperature, air flow rate and feed pump, were fixed as independent variables, while probiotic survival, moisture content, water activity and effective yield were established as dependent variables. The survival of encapsulated L. rhamnosus by spray drying was optimized with response surface methodology, and the stability of the powder was assessed. The optimum spray-drying conditions were an inlet air temperature, air flow rate and feed pump rate of 169 °C, 33 m3·h−1 and 16 mL·min−1, respectively, survival of 70%, air aspiration of 84% and outlet air temperature of 52 °C, achieving an overall desirability of 0.96. The physicochemical and structural characteristics of the produced powder were acceptable for application with regard to residual water content, hygroscopicity, water activity, and particle size. The results indicated that a protein-trehalose-maltodextrin mixture is a good wall material to encapsulate L. rhamnosus, showing important thermal protection during the drying process and increasing survival. However, a decrease in this capacity is observed at an air outlet temperature of approximately 101 °C. The possible effects of the wall materials and the drying conditions on survival are also discussed.

Study on the Steam Source Selection of Feed Pump Turbine Based on Energy Matching

The first phase of a power plant has two subcritical 300 MW units, and each boiler feed water pump is equipped with two with 50% capacity steam driven feed pumps and one 50% capacity electric start-up feed pump. The two steam pumps are put into operation during normal operation. After the heat supply transformation in the unit of the first phase of this power plant and based on the calculation and analysis of the heat balance of the unit, it is found that there will be insufficient output of the feed pump due to the insufficient steam source after the flow-through transformation, which will affect the water supply of the unit and reduce the energy utilization rate. To avoid this, the steam source of feed pump turbine needs to be selected again. Taking the original steam turbine condition of feed pump and the original steam source of feed pump turbine as the research basis, this paper makes analysis on the steam source transformation, and concludes the scheme of steam source selection and reconstruction based on energy matching. The feasibility of the scheme is tested and verified finally.

Peningkatan Efektivitas Cooling Tower dengan Metoda Air High Speed

Cooling tower merupakan suatu alat yang berfungsi untuk menyerap panas pada fluida air yang berasal dari heat exhanger (kondensor, generator air cooler, lube air cooler, boiler feed pump) menggunakan fluida udara yang dialirkan secara natural maupun dialirkan oleh fan. Kalor panas yang diserap oleh udara membutuhkan kontak yang baik antara air dan udara agar terjadi proses pendinginan yang maksimal. Proses pendinginan yang maksimal pada prakteknya tidak bisa terjadi karena dipengaruhi oleh komponen yang terpasang pada cooling tower. Penelitian ini bertujuan untuk merancang efektifitas cooling tower dengan mode high speed. Pengamatan dilakukan pada cooling tower tipe induced draft cross flow. Teknologi Material membedakan material menjadi tiga bagian yakni material cair, material gas dan material padat, disini akan merancang penggunaan material gas ideal yakni udara sebagai salah satu fokus untuk peningkatan fektivitas cooling tower. Metode yang digunakan adalah mode high speed yaitu dengan menambah keceptan udara sehingga panas yang diserap oleh udara lebih banyak. Metode perhitungannya sendiri menggunakan metode pendekatan secara langsung dan tidak langsung. Perhitungan efektivitas dengan metode langsung menggunakan neraca massa dan energi dan secara tak langsung menggunakan perhitungan cara Range and Approac. Setelah menggunakan mode high speed dengan meningkatkan kecepatan angin menjadi 3 m/s diharapkan dapat menaikkan efektivitas sebesar 27,7 %.

Experimental steam turbine T10MW cold end cooling by water spraying

The paper deals with steam flow in experimental turbine T10MW, located in Škoda laboratory. The flow was examined for low or negative outputs of the turbine, i.e. for the so called last stages ventilation. The flow path of the turbine was in the Boiler Feed Pump Turbine (BFPT) version. It had all together 4 stages out of which two were last stages with the outlet to the condenser. In the area of each of the two outlets cooling nozzles were located with water for cooling the outlet steam flow and the area of last blades root cross-sections. Cooling of these areas is necessary due to the compression heat that occurs in the off design (ventilation) regimes. Various proportional amounts of cooling water and flowing steam were tested experimentally in constant pressure behind both last stages. Due to the fact that the flow path and the exhaust hood were fitted with many static pressure taps, thermometers and with the possibility of probing the temperature field along the outlet cross-section height, a number of results were achieved. These were mainly the turbine outputs, steam flows through the blades and cooling nozzles, determination of saturation limits in individual places at the outlet as well as temperature differences measured by the probe and stable thermometers. It was found out that the amount of cooling water was oversized for blade roots cooling, while the flow at the tip was cooled only minimally. The results are beneficial both in terms of further research of steam turbines in low regimes because this is how most newly produced machines are operated and for the designers of these machines.