Recently, the domestic oil price rising, and liquefied petroleum gas and natural gas prices will climb down, and the source of great limitations, such as glass, ceramics, and metallurgy, machinery, chemicals, building materials and other industries have larger fuel consumption, will be transferred to the energy structure in China has an important the status of coal resources.[1]. While coal as a fuel application is also restricted by the country's strict environmental protection policies, air pollution indicators have become the major cities in the level of environmental standards, so in many cities, "coal burning" was included in the list of restrictions expressly. In this form, the gas generator as a form of coal resources and clean utilization, more and more enterprises pay attention to fuel consumption[1].

For these selected gas station enterprises, because of the gas station less contact, what choice of what happened to the gas station? Choose what kind of gas? Choose a few gas furnace? Which kind of purification process...? So a series of problems before us, confused. If the choice is undeserved, may cause unnecessary investment losses, or even less investment, but can not meet the production requirements and result in greater losses. This paper selects the gas station on the gas enterprise perspective, make a brief analysis and exposition of some key problems of selection of the design process, to enable enterprises in the selection of gas stations do well, avoid detours.

1The process of selection. The gas station importance

Gas station selection process design is the first step in design of gas station, for the application of the enterprise, which belongs to a part of the whole project feasibility demonstration file ". The selection process design not only must be combined with practical application requirements of enterprises in the future, but also consider the local factors (such as climate, resources and environment influence etc.). To do the process selection of reasonable design for the enterprise must be tailored to make plan to carry out in-depth understanding of the enterprise, the scheme might be only suitable for the enterprise.

Process selection scheme combined with the actual, not mechanically, often causing incalculable damage to the enterprise. For example, the construction of Shenyang ceramics factory has a gas furnace factory fuel gas station, put into operation in 2001 for spray drying tower milling, the station due to gas purification process does not conform to the northeast "cold winter" climate requirements, put into production after entering the winter, there is double standpipe, washing tower, electric fishing the tar and other equipment and pipeline blockage phenomenon, causing the station unable to normal operation, seriously affected the production, was forced to stop in 2002, causing great losses to the enterprise. Such examples are numerous, more serious, some gas stations built after, because of a link without thinking, which fundamentally unable to meet production requirements, had to be idle, become a pile of scrap metal.

The process of gas station selection design is very important, the design selection of the right, is to ensure the overall implementation of the programme achieved satisfactory effect is the first step.

2The selection process of gas station.

2.1The main content selection process

Station selection process involves more complex content of gas, the designer selection, attention should be focused on the following aspects:

Choose the type of gas furnace

The choice of gas furnace specifications

The standby equipment and equipment for staging consideration

The selection of gas station purification process

The selection of process gas pressure

2.2The selection process is mainly based on

The enterprise of the gas station selection process, a series of factors must be combined with its own resources, environmental requirements, the final product and the use of gas equipment for gas requirements, comprehensive consideration.

2.2.1 Coal gasification

Tangshan Department of industrial technology limited production of gasifier coal gasification is the most commonly used weak caking bituminous coal and anthracite coal gasification, according to preliminary selection, can determine the optimal selection model of gas furnace. For example, it should choose a anthracite gasification type (1M) gasifier; gasification weak cakingcoal the best choice for the two segment (3M) gas furnace or distillation type gas furnace (5M). The specific choice of hot gas but also combined with the process of selection, see table 1.

Table1The priority selection of gas furnace

2.2.2 The quality of coal gasification

The gasification of coal quality mainly refers to the coal in accordance with the standard requirements of the comprehensive index of coal gasifier, atmospheric fixed bed gas producer coal index is shown in Table 2, the ash softening temperature of ST/ DEG C and the thermal stability of TS+6(%), heat QNet,Ar(MJ/kg) as the main index. If the selected coal gasification after comprehensive evaluation can be used for gasification, but the comprehensive index is low, indicating the poor quality of coal for gasification, gasifier selection specifications, should provide the data base in the manufacturer sample, choose one or two grades of gas furnace.

Table2With the technical conditions and test methods of coal quality of atmospheric fixed bed gas producer(GB/T9143-2001)

2.2.3 Enterprises using gas manufacturing finished products or equipment for gas gas quality requirements

Enterprises using gas manufacturing finished products require cold gas station selection process or the process of hot gas gas, and determine the basic process of gas purification equipment selection. For example, the use of gas burning refractory materials, melting glass, building ceramic spray tower of iron and steel industry, coal pulverizing or ladle and sintering, because the product of gas quality requirements are too strict, generally used in hot gas process. For some use of gas direct heating or firing of the finished product quality of gas purification are required, you must use a product for the cold gas purification process. Which is the most typical of the ceramic industry, selection of kiln burning flame bare general cold gas clean furnace, muffle burn or general gas sagger firing the clean degree of the strict requirements, can be used for hot gas, flame bare burning sanitary porcelain, daily-use porcelain and glazed with the building ceramics often the gas in H2The content of S more stringent requirements, the general requirements of gas stations also set desulphurization facilities[1] [4].

In short, enterprise chooses cold gas stations or hot gas stations, purifying process and equipment, how to choose, must combine enterprise products and gas equipment for gas quality requirement.

2.2.4Site location environmental protection area classification

General enterprises are starting from the two aspects of reducing production cost and environmental protection, considering the construction of gas station. But the first step is to reduce production costs and reduce the cost of investment, environmental protection is the premise of strengthening the selection process and equipment station considered from the environmental point of the gas, it is bound to increase capital investment, the formation of contradiction and reduce the cost of investment, how to adjust the contradiction has become the enterprise construction at the early stage of consideration.

From the perspective of national environmental policy, which first confirm the environmental regional position belongs to the enterprise site according to the national standard and the corresponding standard, then according to the requirements of national environmental protection category belongs to regional and enterprise requirements, determine the choice of gas station technology and equipment, but the long-term development of enterprises, enterprises in the premise of their own conditions allow suggestions next, try to use the above station technology and equipment for environmental protection and energy-saving environmental protection requirements of the occurrence of regional gas category.

2.2.5Requirements for continuous operation degree of gas equipment

With the continuous operation of the gas equipment requirements directly related to the gas station standby equipment selection. For example, the production of construction ceramics spray drying tower, according to the requirements of the production process of building ceramics in general every week to stop a tower, so, standing in the selection of equipment for the production of building ceramics spray drying tower supporting gas, in addition to the pump and fan need to use standby, other equipment can not consider standby; and the glass industry is different, because the glass furnace generally requires a one-time continuous operation to five years, so, for supporting the glass furnace gas stations with gas furnace, should not only consider the choice of load type furnace more than a large number of degrees, but also to try to set the standby furnace.

2.2.6 Gas equipment for gas pressure requirements

The use of different gas pressure and gas equipment requirements vary, some require higher than 20000Pa, and some require only about 1000 Pa, which requires us to choose the gas pressure process, according to the gas equipment to the gas pressure requirements, combined with the layout of the gas pipeline, with a reasonable gas compressor, to to save the construction cost and reduce operating cost effect.

2.2.7The enterprise overall construction planning requirements

Construction enterprises generally have the overall planning, there may be a need for stage construction. If the whole engineering construction by stages, in the design of a gas station, it is necessary to take into consideration, not only to the two or three land reserve planning, and be in a period of time to consider the equipment selection and after connection and supporting several projects. In this way, can greatly reduce the overall project investment.

Conclusion:

In summary, the reasonable selection of gas stations on the process of comprehensive establishment enterprises reduce the construction investment and operation cost is very important, and influence factors of gas station and the selection process is complex, the influence of various factors on the selection process of gas station requirements often has many contradictions, which we need in the process of selection, comprehensive consideration, to distinguish between primary and secondary, rational choice, reasonable to make maximum use of the.