1 TOPIC COMMON INFORMATION
1.1 Topic importance
Dewatering mining enterprises is an important element of all mine technical equipment system, and its effective work provides defines the fail-safety and reliability in mining minerals [1].
Existing base equipment of controlling dewatering plant does not control parameters of replacing working point to the pump pressure characteristic and that’s why, doesn’t supply its working with changing of the given characteristics during exploitation, in zone of industrial use.
That’s why, widening functional possibilities of existing base, main dewatering plant automation equipment by means of using radically new pump controlling methods and facilities in zone of industrial use is of great importance topic.
1.2 Aim and objectives of work
The aim of this work is to increase the level of mine dewatering automation by means of supporting pump work in zone of industrial use.
1.3 Scientific novelty and practical value
Scientific novelty of this work lies in getting new knowledge in controlling pump plant and increasing its effectiveness.
As the research result, developed system of mine dewatering plant control, amounting to base equipment (ВAВ. 1M), in zone of industrial use, will help to define the reference values of pump control, form appropriate warnings, that means increasing of reliability of pump work. It will also help to reduce electricity bill and emergency situations during pump plant exploitation.
2 REVIEW OF EXISTING AND PROJECTED RESULTS
2.1 Mine dewatering plant as the object of automation
Technological scheme of the main mine pump installation, showed at figure 3.1, consists of suction sump 1; supply pipe 2, equipped with take-up net (ПС) and baffle gate (OK); pump 3; discharge pipe 4 with baffle gate (ОК), control catch (ЗР) with valve drive (ПЗ) and two terminal switches. One of them, (КВЗ) controls closed state of catch, and the other (КВО) controls its opened state. There is also flow indicator of variable pressure Р, installed at feed pipe; manometer (M), installed at pipe discharge connection [2].
Figure 2.1 – A technological scheme of main mine pump installation
For the pump work to be economical, its operation mode should be set within the limits of working pitch characteristic, limited with the meaning of efficiency factor [3]:
ηдоп = (0,85-0,95)⋅ηmax
Within the correct choice of pump and pipeline, one condition should be observed: Q2 < Q0 < Q1, where Q0, Q1 and Q2 are minimal and maximal pipe flow in work zone (figure 2.2).
Schedule of changing pump and pipeline net pressure characteristics is shown at figure 2.2.
Figure 2.2 – A schedule of changing pump and pipeline net pressure characteristics
2.2 Basing of main mine dewatering automation direction
Chosen base equipment ВAВ.1М carries out all main requirements to the dewatering plant automation. Though its functional possibilities don’t contain supporting of pump plant in zone of industrial use, under the conditions of noncavitation pump work. That’s why one of the ways to improve the dewatering plant automation system is equipping it with additional device, that would carry out required function.
2.3 Algorithm of developing device
Control-flow chart of dewatering plant control is shown at figure 2.3, where developing control block of pump plant in zone of industrial use of pump УНЗ is pointed with thick lines. It also shows its correlation to other algorithm blocks. The essence of operations and logical conditions is showed in correspondent blocks.
Figure 2.3 – A control-flow chart of dewatering plant control
2.4 Basing and developing of schematic solution of automation unit
Structural scheme of main dewatering plant automation equipment ВАВ.1М is shown at figure 2.4, where developing device of pump plant control in zone of industrial use УНЗ is pointed with thick lines.
Figure 2.4 – A structural scheme of main dewatering plant automation equipment ВАВ.1М
Structural scheme of dewatering plant control device in zone of industrial use УНЗ is shown at figure 2.5
Figure 2.5 – A structural scheme of dewatering plant control device in zone of industrial use УНЗ
On the base of structural scheme and standards CSCD we will make functional scheme of designed device (figure 2.6) [4].
Figure 2.6 – A functional scheme of designed device
As the result of this work, short characteristics of main mine dewatering is realized (envisaged). The review of existing solutions is made, the analysis of existing methods of pump plant control is carried out and the frequency regulation is chosen at first stages, as the most appropriate way. Structural and functional schemes are designed (on the modern elemental base, using microcontroller АТ90S8535 (АTmega16), a work algorithm of pump plant control device in zone of industrial use by means of flow throttling is designed.
Use of developed pump plant control device, in zone of industrial use, by means of flow throttling, within the equipment ВАВ.1М will help to control the parameters of re-placing of work point to the pump pressure characteristic and, as the consequence, it will help to reduce electricity bill, emergency situations and service labour-output ratio.
Later on, it is planned to design dewatering plant control device in zone of industrial use by means of changing speed of rotation of pump engine shaft, to compare it with pump plant control device by means of flow throttling and to chose the most appropriate variant.
1. Повышение эффективности водоотливных установок: Учеб. пособие/С.П.Шевчук. – К.: УМК ВО, 1990. – 104 с.
2. Гейер В.Г., Тимошенко Г.М. Шахтные вентиляторные и водоотливные установки: Учебник для вузов. – М.: Недра, 1987. – 304 с.
3. Попов В.М. Рудничные водоотливные установки. – 2-е изд. перераб. и доп. – М., Недра, 1983. – 304 с.
4. ГОСТ 2.702-78. Правила выполнения электрических схем.