Program-controlled technology to optimize power plant in Water Treatment
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Abstract: The instrument of program-controlled water system, as well as to improve and perfect. By optimizing the technical program at the water treatment plant, and achieved good social and economic benefits of the water treatment sector have a good reference.
Key words: program; water treatment; switch; water; regeneration; benefits
Key words: TK223.51 Document code: B
Instrument-based thermal power plant water treatment system is divided into three phases, each have four-bed-yang, yin-bed four-bed and three mixed. 1996 Phase III expansion of the water system of program-controlled technology, by the end of 2002 for all water treatment system reform program, keeping the existing system, an increase in the first and second phases OMRON PLC Systems (lower plane), together with Two operator station (the PC) and a gateway system can operate at the same time functions, and network connection through the station engineer.
The new program-controlled upper control system software used Intellution's iFIX2.6, it is to achieve a set of field data collection, process visualization and monitoring of industrial process automation software solutions, iFIX software and under the control of digital data communication system on I / O drive to achieve.
Three of the original program-controlled system for many years, there are many problems. The combination of water treatment system reform program, efforts will be program-controlled technology with the production practice more efficiently, optimize its production in water treatment applications, has achieved very good results.
First, the existing problems
Three of the original program, including the scope of Phase III expansion of the Renewable and switches, program-controlled system over a period of time after the operation revealed a lot of problems.
1. Process steps not perfect
Switch-renewable water and when the operation more complicated process, in particular acid (or base) of renewable more steps, such as bed-yang, including small anti-wash (or anti-washing) water, pressure-top, into the acid replacement. Small is washing, washing, and so are the steps. The original program-controlled system of simple steps, each step in the transition between the non-step switch on the air valves of different types, different speed of movement, resulting in frequent damage to equipment.
2. Operation unreasonable time
The original set of operating time is not very reasonable. These step-by-step procedures for the operation time can change, but by the needs of professionals in the configuration screen operation, is not easy.
In addition, the program steps in the process of time adjustment can not only operate in the operation before or after the adjustment, and the pressure, temperature, flow, level, the impact of factors such as the concentration of operations is the impact of real-time, it appears to be a lack of Flexibility.
3. The lack of depth of the switch failure of preventive measures
As a result of the reasons for equipment or operator error led to the failure of the depth of the switch can not be found in time, cause water pollution. Even when serious impact on the turbine and boiler safe and stable operation.
4. The lack of automatic checking mechanism Assessment
As a result of the operation led to the failure of the work, the system can not be real-time record.
Second, measures to improve
1. Improving the procedures for the establishment of the steps
In order to meet the needs of auto program Renewable, according to production practice, the various switches of the steps in detail division in each of the steps behind all the steps in response to an increase of the valve. Effective steps to address the conversion of various pneumatic valves to open at first caused by the sudden switch customs hold back pressure in order to avoid the switch in the resin layer chaos, running resin, acid (or base) and low utilization of the situation.
2. To develop a reasonable operating time
Adjustable time on the steps, through repeated tests to determine a reasonable operating time. In addition, the PC screen to operate the additional step-by-step process was time to set the table, at any time in the PC changes.
3. Additional "step-by-step jump" and "delay" button
As the operator of renewable more in the "step-by-step timetable for the operation procedures" arbitrary changes easily cause confusion. To this end, the addition of the "leapfrog" and "delay" button, so that when renewable on the basis of actual use, an increase of renewable sources of flexibility, at least with the base, the best regeneration effect, in order to reduce acid Alkali consumption.
4. Provide adequate water to determine conditions of the end
Based on the exchange's specific situation, additional water system, water system, the acidity (or conductivity) as the end of the water to determine the conditions for failure to prevent the switch depth, increase the difficulty of the next cycle of regeneration, and to avoid waste of acid-base . More importantly, to prevent water pollution and ensure the security and stability of production. A switch fails, automatically put into operation in another switch, the failure of the switch that is the beginning of regeneration, so as to enhance the degree of automation. As a result of exchange between there may be some differences, so each of the switch settings are listed separately, in accordance with the production in order to change at any time.
5. PC automatically checks new assessment mechanism
In the PC "about the" additional column of the "Records of the search operation." "Records of the incident investigation." Before the operation of the PC can query at any time, it can be an effective screening test, greatly reducing the false phenomenon. As the amount of acid-base with an accurate record of acid-base consumption decreased, since the water rate has been effectively controlled, the PC has essentially no longer crash. In the assessment of responsibility for accidents or unusual, may be well documented.
6. Strengthening the training of personnel
Program-controlled system has been improved, staff training is particularly important. To carry out various forms of training, as a point of order examinations, technical drills and exercises and counter-contest, and so on, through the operation and on-site demonstrations, running the basic operations can be skilled and able to deal with a few simple emergencies, in order to optimize the application of the technology program , Particularly in the application of renewable sources of acid-base and lay a good foundation.
Third, effective
Instrument of improved water program, the operating system more reasonable and scientific production, to ensure the safety of the equipment to run the economy, to promote security and stability of the power plant's production. Sound assessment of the automatic check mechanism to enhance the operator's sense of responsibility, to create a good social and economic benefits.
1. Improved the passing rate of regeneration
2002 and 2003, respectively, renewable two-year program-controlled switches 2674 and 3 982 times, and has a pass rate of regeneration were 98.73% and 99.92%, and improved program-controlled system, the passing rate of increase of renewable l.2 percentage points.
2. Since the reduction in water consumption
To improve the program-controlled switches after a water cycle operation to measure time, with each cycle about the use 14min, such as to the steps of the average flow for the 80t / h calculation, a bed-yang of water in each cycle of water-saving low-silicon 12.00t; a negative bed each cycle to save water in addition to salt 18.67t. 2003-yang, yin-bed for renewable 1799,2022 times, and has a total water-saving low-silicon 21588t, in addition to salt water 49 750t. That is, since only a water-saving 142,000 yuan / year.
3. To reduce the consumption of acid-base
2003 base year-on-year decline in consumption significantly, the control was so good due to the improvement of program-controlled system. Acid consumption in 2003 were reduced to 0.423kg / t and 0.425kg / t, year-on-year decrease of 0.043kg / t and 0.012kg / t. In addition to the system in 2003 a total of saline 53 326 391t, acid-base economy were 229.3t and 64.0t, about 159,000 yuan.
