Metallurgical enterprises have great potential to carry out energy saving of steam system
many thoughts done on developing steam system
energy-saving in metallic enterpriseswang Qian
(National metallic Bureau) Abstract: the paper discusses the present situation of steam system in metallic industry, analyzes energy Savi literally. It can only be used to do single 1 tensile tests ng potential and effects, and puts forward some advice for doing the work well.
keywords:steam system energy saving as a national basic industry, the metallurgical industry has large production scale, long process, many kinds of energy consumption and high energy consumption. In 1998, the comparable energy consumption per ton of steel in large and medium-sized steel production enterprises was 901 kg of standard coal, 245 kg of standard coal higher than that in Japan, 37% higher. Therefore, the metallurgical industry has always attached importance to energy conservation. Through the efforts of the whole industry, the comprehensive energy consumption per ton of steel decreased from 2.52 tons of standard coal/ton of steel in 1978 to 1.29 tons of standard coal/ton of steel in 1998, and remarkable achievements were made. Especially after the ninth energy saving working conference of the metallurgical industry and the experience exchange conference of Jigang, energy saving and consumption reduction has become a strategic measure for the whole industry to survive, develop and realize the transformation of economic growth mode. Energy conservation work has also developed from management energy conservation to a new stage of technical energy conservation that improves the comprehensive utilization of energy and resources in a systematic and all-round way. This marks the need to do a good job in energy conservation in all aspects of technology and management. Therefore, with the full system and all-round in-depth development of energy conservation, the steam energy conservation of power system is also increasingly on the agenda. Fast moving enterprises have made bold attempts and achieved good results
according to the statistics of some large and medium-sized enterprises, steam energy consumption accounts for about 10% of the total energy consumption of metallurgical enterprises. The annual energy consumption of metallurgical industry is about 130 million tons of standard coal. Calculated at 550 yuan/ton of standard coal, the annual steam energy consumption cost is about 7.15 billion yuan. If the energy-saving rate of steam pipe transformation is 10%, the annual energy-saving benefit of the whole industry is about 700million yuan (practice has proved that the energy-saving effect of steam equipment is far more than 10%). It can be seen that although the proportion of steam in the energy consumption of the industry is small, due to its large scale, the economic benefits are also considerable. With the increasing global attention to environmental protection, saving steam also has important social benefits. Therefore, it is imperative to carry out energy conservation of steam system. 1. Current status of enterprise steam system. As the steam system is an auxiliary system in metallurgical enterprises, the proportion of energy consumption is small, which has not been paid attention to for a long time, and the efficiency of the whole system is low, with about 10% - 30% energy-saving potential. Compared with the foreign advanced level, there is a huge gap. These problems are mainly reflected in:
1.1 measurement is not perfect
steam users are divided into production users and domestic users. According to the provisions of the measurement method, steam production ★ 8) static accuracy of sensors: load limitations, endogenous units and each user should be equipped with measuring instruments. Due to various reasons, many places on the site are not equipped with measuring instruments, and some places are equipped with incorrect readings, which often leads to wrangling between enterprise departments. If the assessment of steam consumption is not implemented, it is difficult to mobilize the enthusiasm of energy conservation
1.2 serious leakage
due to the lack of maintenance and operation of steam pipes and some equipment throughout the year, serious corrosion, coupled with water hammer, thermal insulation and other problems, the problem of leakage is widespread in the process of steam transmission. In some places, the main pipeline leaks steam, and the harsh sound can be heard from a long distance
1.3 a large amount of condensate is not recycled
the value of condensate includes calorific value and demineralized water, which is equivalent to about one quarter of the value of steam (due to different sources of steam, the price of enterprises is 50 ~ 120 yuan/ton). The vast majority of enterprises directly discharge this valuable condensate. Some failed to recycle the condensate even though there were recovery pipelines due to technical reasons
1.4 the quality of the products used in the key parts of the steam pipe is unqualified
the products used in the steam system are shoddy, of low quality, and of incomplete varieties, which is a common problem. Take the steam trap as an example, there is a lack of high-performance and high-quality steam traps, some of which come from enterprises that do not have the test conditions and production conditions specified in the national standards; Some products are officially eliminated by the state, with no guarantee of quality, poor reliability and short service life, so that enterprises have to stock a large number of valves for standby at any time. Nevertheless, the steam leakage rate still seriously exceeds the standard, which is far from meeting the needs of enterprises. Other pipe products, such as temperature control valve, pressure reducing valve, condensate recovery pump, etc., also have similar problems
1.5 the technical level of system design, product selection and pipeline installation is relatively backward
for example, in the process of steam transmission, condensate is produced due to heat loss, so the condensate produced should be discharged from the pipeline in time at the low point and end of the pipeline, otherwise high-temperature condensate will corrode the pipeline and lead to water hammer, which will do great harm to the pipeline. At present, most enterprises treat these condensate in an incorrect way and directly open the valve for discharge. Water leakage can be seen everywhere. The correct way is that during the use of steam, the packaging branch should set up a new material research center and install a steam water separation device to drain water scientifically and reasonably. Although some enterprises have added drainage devices, there are errors in the drainage method. For example, the unit drainage method should be adopted, and the combined drainage method should be adopted to save trouble. Special drainage, such as siphon, should be adopted, while ordinary drainage, etc. can not achieve the purpose of drainage. Some simply do not have any steam water separation device. Some enterprises are correct in tube design, but there are many mistakes in product selection and installation. Still take the steam trap as an example. It is the most common practice to look at the caliber when selecting the type, but in fact, there are still many knowledge in the steam trap. Due to different steam pressure, different drainage, and different applications, the types and models of steam traps that close the oil delivery valve are also different. There are many mistakes in the installation of steam traps, such as inversion and inclination
1.6 low level of management and maintenance
for a long time, the steam system has not received due attention in actual production, and most enterprises have left the steam system at its own discretion. A common phenomenon is that the number of boilers and steam tonnage are increasing, but the steam supply is always tight, especially in winter. Some enterprises
LINK
Copyright © 2011 JIN SHI