Currently, the development of "recycling economy" has become the mainstream of world economic development. "Circular economy" is a kind of efficient use of resources and recycling as the core, low consumption, low emission, high efficiency of basic signs, in line with the concept of sustainable development, economic growth, is the "mass production, mass consumption, a large number of gas "fundamental transformation of the traditional model [1-5].
Material as the basis for economic development and pilot for the tremendous wealth of the community. However, from the resources, energy and environmental perspective, material extraction, production, use and disposal process is a continuous consumption and destruction of human life space of the process. As people's awareness of the environment and sustainable development concepts to take root, the world has gradually legislation that requires manufacturers of products throughout the product life cycle is responsible for the environmental impact, consumers are increasingly turning to green environmental protection and good the product. Welding industry is facing the same problem. Although Welding Electrode Supplier is a traditional industry, but after the transformation and upgrading of modern high-tech, is toward efficient, automated, intelligent, energy-saving, environment-friendly welding direction.
Welding has been one of the industries polluting emissions, so effective in improving the working conditions of welders, welding to reduce the dust has become an important issue facing workers. In response to this issue, industrialized countries have begun to study environmental load of welding materials and welding product life-cycle environmental impact, and start a new generation of low toxicity, low-dust environment in the type of welding materials research.
To a new generation of low toxicity, low dust environment in the type of welding material research, has begun to gradually carry out the main ingredient of welding materials and accessories of environmental load assessment in order to get a variety of accessories to environmental factors, type of welding coordination environment as a guide materials research. In this and several welding core materials only a preliminary assessment.
An electrode of the environmental load evaluation
Electrode production process involves many chemical and physical variables relevant data. Although these data reflect the state of electrode production process damage to the environment, but they are not the same dimension, it is difficult normalized and compared with each other the extent of damage to the environment, making it difficult to accurately understand the environmental load electrode. Clearly, research workers, the electrode on the requirements and want to load environment specific and quantitative, so can the electrode production process generated waste such as waste gas, dust and other compliance with environmental standards have a general understanding. According to every detail, the environmental load of the larger part should be analyzed and improved to reduce the environmental load.
1.1 Identify the assessment objectives and scope
Analysis or assessment objectives and define the exact scope of the analysis or assessment of product analysis or assessment of an object determines the direction and depth. It has to be determined include: evaluation of the purpose and scope, data types and collection methods, the system boundary, the evaluation methods. This paper mainly studied the electrode part of the added materials such as steel core, marble powder, mica, feldspar powder and fluorite powder before the electrode made of the environmental load, that is, raw materials, the environmental load.
1.2 Data Collection
In order to truly reflect the specific impact on the environment situation, an important collection of relevant data. Only in detail, based on reliable data to the data of the specific circumstances, the appropriate choice of assessment models, making the assessment results to reflect the true situation. According to data collected detailing the various stages of a variety of input and output inventory and analysis, so as to target the next phase of various factors on the performance analysis of the impact assessment preparation.
1.3 Determination of environmental impact factors
In the environmental load evaluation, the evaluation of environmental impact factors is the most basic part of the load, that is, environmental load factors of environmental impact assessment is carried out for various calculations and evaluation. For this paper, discussed the environmental impact factor refers to the waste environmental factors. Factor is the environmental impact of waste in the production process of each of the various materials, a variety of emissions on the environment will have a direct or indirect impact on the waste, the basic, including waste water, waste gas, waste and so on. To refine and classification of each waste, the resulting impact on the environment of many substances, each of which comes down as a waste material on the environmental impact factors.
1.4 Data processing environmental factors
For the handling of environmental factors, the first environmental impact to a dimensionless dimensionless factor into the data, the various units of varying units, of environmental impact factors, which can be seen that kind of impact factor in the whole production process of environmental impact of the load increases, the material can be seen in a single production process all the environmental factors affect the magnitude of the load on the environment.
1.5 The selection and weighting factor to determine the
Throughout the production process, each of the environmental impact of waste environmental impact of external factors are different, and some trace greater impact on the environment, while others just the opposite. In order to grasp the overall situation, the overall measure, leads to the weighting factor to each of the impact factor of the nominal impact on the environment size, to measure the impact of each risk factor level. The weighting factor is not out of thin air, the weight coefficients to be determined, to ensure scientific, rational, feasible and simplistic. Determine the weight coefficients are generally divided into / case: the statistical weight factor; expert weighting factor; equivalent weight factor.
1.6 model
Application of non-continuous function of the environmental load evaluation model to assess raw materials. Formula-based assessment model superimposed non-continuous function ELV = Σ {ELV (n)}.
Type of evaluation model is superimposed environmental factors affecting each of the right to re-factor of the mathematical superposition. This mathematical model is characterized by simple algorithms directly, and for the calculation process and the results are more intuitive. Drawback is that since the algorithm is simple and there may be deviation. However, this model requires that data collection is not very complicated, in line with the actual situation of data collection, thus, the study calculated using this model.
1.7 Data Analysis
The material in the collection of relevant data, the application of environmental impact assessment methods, environmental factors will be based on specific data values, according to a certain extent with an integer that the environmental impact of its magnitude. Then a variety of substances in each stage of the magnitude and impact of a listed weight coefficient matrix, and then summarize them, find the total value of the environmental impact. The higher the value, indicating the greater impact on the environment, the stage should be a reasonable analysis and improvement, in order to achieve the purpose of reducing environmental load.
2 Data Acquisition
2.1 welding core production process of data collection
Welding core environmental load can be approximated as the environmental load of steel. The environmental load for steel production, there are many publicly available data and reports related to [6]. To the solder from the iron and steel smelting process ID of each core sort, collect environmental factors that concrete waste and emissions, on behalf of environmental factors to j, i said waste and emissions standards. Steel production process is: mining (j = 1) → washing (j = 2) → coke (j = 3) → sintering (j = 4) → iron (j = 5) → steel (j = 6) → continuous casting (j = 7) → Hot (j = 8) → Cold (j = 9). In the CO2 Gas Shielded Welding Wire process, mainly to collect the following environmental factors, namely, waste emissions (i = 1); suspended matter emissions (i = 2); phenol emissions (i = 3); oil discharge volume (i = 4); emissions (i = 5); sulfur dioxide emissions (i = 6); soot emissions (i = 7); carbon monoxide emissions (i = 8) nitrogen oxide emissions (i = 9 .)
Description: Number Class A emissions for the waste water, A behind the emissions figures for the number; B category for the exhaust emissions, B behind the figure for the number of emissions; C emissions for the category of solid waste , C behind the emissions figures for the number. Unit: t / t refers to the emissions to produce 1t steel material quality.
Description: Number Class A emissions for the waste water, A behind the emissions figures for the number; B category for the exhaust emissions, B behind the figure for the number of emissions; C emissions for the category of solid waste , C behind the emissions figures for the number. Unit: t / t refers to the emissions to produce 1t steel material quality.
2.2 marble powder, mica, feldspar powder and fluorite powder data collection
To get more practical and first-hand information and data to a production of electrode materials based factories, mainly produce marble, mica, feldspar, fluorite, ilmenite. Marble powder, feldspar powder and fluorite powder processing procedures: Mining - crushing - screening - grinding, and mica processing more water selection process. Specific data shown in Table 3.
3 welding core materials and the environmental impact assessment added
3.1 welding core of the production process of environmental impact assessment
Find the core production process of welding a variety of environmental factors i j specific data, in order to build the core of the production process welding impact assessment matrix, the need for specific data processing to obtain the magnitude and impact of specific weight factor. Therefore, the provisions of the values ??of various environmental factors in the 10-5 and 10-4 below, the impact of the range of 1; 10-3 below, the impact of the range of 2; in 10-2 below, the impact rate of 3 ; at 10-1 the following, affecting a range of four; under 100, the impact ranges from 5; in 101 or less, affect the rate of 6; in 102 or less, affect the rate of 7; in 103 or less, affect the rate of 8; in 104 The following affect the rate of 9; in 104 or more, the impact rate of 10. This can clearly be seen that each process in the impact of each factor amplitude, as shown in Table 4.
As can be seen from Table 4, the greatest impact on the environment is the process of coking process, the environmental impact factor of 19.44, followed by sintering (19.34) and iron (18.93). Beneficiation process is less affected (0), casting (0), hot-rolled (0), cold-rolled (0.03). Then, from the environmental factors impact on the environment point of view, the greatest impact on the environment is water (9.54), followed by gas (8.86), sulfur dioxide (6.93), carbon monoxide (7.03), smoke (6.93), nitrogen oxides (6.71), suspended solids (5.88); less impact on the environment is oil (4.93), phenol class (4.00).
3.2 marble powder, feldspar powder, fluorite powder, mica production process of environmental impact assessment
For these types of minerals in the production process of environmental impact assessment in the choice of weighting coefficients are the core production process welding fume emission coefficient of the weight reference, the initial selection of marble powder, feldspar powder, and powder production processes in the fluorite weight factor. Namely: in the broken phase 0.14; screening phase 0.12; final polishing filter is 0.13. For mica, take: broken grinding stage 0.24, 0.21 selected as the water, dry grinding 0.13, 0.12 final screening. Various environmental impacts of minerals production process
Impact assessment as shown in Table 5.
4 Conclusion
From the impact factor of view, the core or steel welding process of environmental impact factors of production to achieve 68.62,4 kinds of accessories of the production process of environmental impact factor of 2.8. Taking into account the weight of wire or welding with powder factor or a factor of 50% plus 80%, or welded wire with the environment and thus the maximum load.
In the marble powder, mica, feldspar powder and fluorite powder production process impact on the environment than the solder core is relatively small, which is their production process is simple, single-related waste. Marble powder, feldspar powder and fluorite powder production process of the main environmental factors as dust, its entire production process, the degree of influence of 0.39. These three kinds of powder of the overall environmental impact of 1.17, with all the production process welding core environmental impact comparison, the magnitude of their impact is still relatively small. The production of mica in the process of environmental impact and marble powder, feldspar powder, fluorite powder production process compared to the relatively large, the entire production process of the impact of residues of 2.80, compared with three kinds of powder magnitude of the sum of the effects even higher, which is the production process mica.
The study only a few accessories and welding rod cores for assessing the environmental load, add auxiliary electrode environmental load evaluation is a larger system, the need to establish a complete database, this work has just begun, but also a lot of work.
D502 valve surfacing Welding Electrode in line with GBEDCr-A1-03
Description: The D502 is titanium calcium type skin the 1Cr13 type valve surfacing electrode can be AC ??and DC welding process. Surfacing metal for the 1Cr13 half ferritic high-chromium steel. Surfacing layer has the characteristics of air quenching, generally not to be heat-treated, uniform hardness and softening can also be annealed in the 750-800 ° C, when heated to 900-1000 ° C air-cooled or oil quenched, and the re-hardening.
Uses: This is a versatile surfacing electrode for surfacing operating temperature below 450 ℃ carbon steel or alloy shafts and valves.
D507 valve surfacing welding rod in line with GBEDCr-A1-15
Description: The D507 is a low hydrogen sodium type coating the 1Cr13 valve surfacing welding rod, using DCRP. Surfacing metal for the 1Cr13 half ferritic high-chromium steel. Surfacing layer has the characteristics of air quenching, generally not to be heat-treated, uniform hardness and softening can also be annealed in the 750-800 ° C, when heated to 900-1000 ° C air-cooled or oil quenched, and the re-hardening.
Uses: This is a versatile surfacing electrode for surfacing operating temperature below 450 ℃ carbon steel or alloy shafts and valves.
D507Mo valve surfacing welding rod in line with GBEDCr-A2-15
Description: The D507Mo the 1Cr13 valve low hydrogen sodium type coating surfacing electrode. Surfacing metal for the 1Cr13 half ferritic high-chromium steel. Surfacing layer with air quenching characteristics of the deposited metals with high temperature hardness, good thermal stability, erosion resistance. D577 electrode used in conjunction with good anti-abrasion performance. Surfacing process is simple, no preheating before welding without heat treatment after welding using DCRP.
Purposes: to surfacing operating temperature below 510 ℃ temperature and high pressure cut-off valve sealing surface. Gate valve sealing surface should be of the electrodes and the D577 electrode used in conjunction with (valve seat and disc, respectively, with more than two electrodes). D507MoNb valve surfacing welding rod in accordance with GBEDCr-A1-15
Description: D507MoNb low hydrogen sodium type coating the 1Cr13 type valve Nickel Electrodes, the use of DCRP, drug skin by adding the appropriate amount of Mo, Nb strengthened and stable element, it is surfacing metal has good resistance to oxidation and anti-crack performance.
Uses: used for the operating temperature below 450 ℃, the low pressure valve sealing surface of the surfacing.
D512 valve surfacing electrode comply with GBEDCr-B-03
Description: The D512 is titanium calcium type skin the 2Cr13 type valve surfacing electrode, AC and DC welding process. Surfacing metal 2Cr13 martensitic high chromium steel. Surfacing layer has the characteristics of air quenching, generally without heat treatment, uniform hardness, softening annealing in the 750-800 ° C, when heated to 950-1000 ° C air-cooled or oil quenching can be re-hardened.
Purposes: D512 is a versatile surfacing welding rods, welding layer than the D502 is harder and more wear-resistant, difficult to process for surfacing carbon steel or low alloy steel shaft, superheated steam valves, mixer paddle, screw conveyor blades.
D516MA valve surfacing electrode comply with GBEDCrMn-A-16
Description: D516MA the low hydrogen potassium type coating of chromium-manganese steel surfacing electrode deposited metal has good abrasion resistance, heat resistance, corrosion resistance and thermal crack performance, welding technology, welding without preheating, without heat treatment after welding, surfacing layer for cutting.