The objective of this study was to describe the occupational accidents and distribution of accidents in different groups. This is a cross sectional study in which the interview with structured questionnaire was used to collect information on occupational accidents and distribution of accidents among 2525 workers in different groups. Our results indicated that the occupational accident prevalence was 4% in 10 year period among workers of heavy, light and chemical industries. The occupational accident rate was highest in the heavy and chemical industry and the workers who worked longer in the industry have lower occupational accident prevalence.
Accidents, Occupational ; Metallurgy ; Chemical Industry

Typical solid wastes contain many metal resources, which are worthy of recycling. The bioleaching of typical solid waste is affected by multiple factors. Green and efficient recovery of metals based on the characterization of leaching microorganisms and the elucidation of leaching mechanisms may contribute to the implementation of China's "dual carbon" strategic goals. This paper reviews various types of microorganisms used for leaching metals from typical solid wastes, analyzes the action mechanism of metallurgical microorganisms, and prospects the application of metallurgical microorganisms to facilitate the application of metallurgical microorganisms in typical solid wastes.
Solid Waste ; Metals ; Metallurgy ; Carbon

Humans ; Lung Neoplasms ; etiology ; Metallurgy ; Occupational Exposure

Alveolitis, Extrinsic Allergic ; Humans ; Metallurgy ; Occupational Diseases

Objective: To analyzes the various occupational health investment and occupational health output of a steel enterprise, and propose a reasonable occupational health investment plan for this enterprise. Methods: In march 2016, various occupational health input and output data of various branches of an iron and steel company in 2015 were collected, and the efficiency of occupational health inputs and outputs of each branch was evaluated using data envelopment analysis (DEA) , and the branches with non-optimal efficiency were adjusted to propose a reasonable occupational health investment plan. Results: Among the branch plants investigated by this steel company, the occupational health input-output efficiency values of ironmaking north plant, power plant, hot rolling plant and stainless steel plant were 1, while the occupational health input-output efficiency of gas making plant, cold rolling plant, metallurgical furnace charge plant, coking plant, ironmaking south plant and long product plant were not the best, and the cold rolling plant has the lowest efficiency value of 0.759. For the cold rolling plant, only the parameters of acid rolling plant satisfy α=1 and s(-)=0, s(+)=0, while the remaining four workshops do not meet. After adjusting the inputs of each part according to the parameters, the occupational health output of the remaining four workshops can reach 1.7044, 2.0238, 1.3152 and 1.2136 times of the current workshop, respectively. Adjustment plans for other branch factories with unreasonable investment structures are also presented in the corresponding tables. Conclusion: The occupational health investment structure of the ironmaking south plant and other branches in this steel enterprise is unreasonable, and the adjustment using data envelopment analysis can maximize the benefits of its occupational health output.
Financial Management ; Iron ; Metallurgy ; Occupational Health ; Steel

OBJECTIVETo analyze systematically the characteristics of occupational hazards in the foundry, and provide precise data for epidemiology studies and control of occupational hazards in the foundry.

METHODSData of airborne dust, chemical occupational hazards and physical occupational agents in environment in the foundry from 1978 to 2008 were dynamically collected. Mean concentration and intensity (geometric mean) of occupational hazards were calculated by job in different years.

RESULTSMain occupational hazards in the foundry were silica, metal fume, noise and heat stress. Silica existed in all of main jobs. The mean concentration of silica before 1986 was an extremely high level of 8.6 mg/m(3), and then remarkably dropped after 1986, with the level of 2.4 mg/m(3) from 1986 to 1989, 2.7 mg/m(3) from 1990 to 2002 and 2.7 mg/m(3) from 2003 to 2008. The trend of silica concentrations by job was consistent with that in general. Silica concentrations among jobs were significantly different, with highest level in melting (4.4 mg/m(3)), followed by cast shakeout and finishing (3.4 mg/m(3)), pouring (3.4 mg/m(3)), sand preparation (2.4 mg/m(3)), moulding (2.1 mg/m(3)) and core-making (1.7 mg/m(3)). Concentration of respirable dust in pouring was highest (2.76 mg/m(3)), followed by cast shakeout and finishing (1.14 mg/m(3)). Mean concentration of asbestos dust in melting was a relative high level of 2.0 mg/m(3). In core-making and sand preparation, there existed emission production of adhesive, with mean concentrations as followed, ammonia (5.84 mg/m(3)), formaldehyde (0.60 mg/m(3)), phenol (1.73 mg/m(3)) and phenol formaldehyde resin (1.3 mg/m(3)) also existed. Benzene and its homologues existed in cast shakeout and finishing, and the level of benzene, toluene, xylene was 0.2 mg/m(3), 0.1 mg/m(3) and 1.3 mg/m(3), respectively. In pouring and melting, there existed chemical occupational hazards, including benzo(a) pyrene, metal fume (lead, cadmium, manganese, nickel, chromium) and gas(hydrogen sulfide, phosphine, sulfur dioxide, carbon monoxide). Mean concentration of benzo(a) pyrene was a low level of 1.80 x 10(-4) microg/m(3). Physical occupational agents in the foundry were noise, heat stress and vibration. Intensity of heat stress was high in melting, pouring and cast shakeout and finishing, with the level of 30 degrees C, 29 degrees C and 26 degrees C, respectively. Noise was high in cast shakeout and finishing and core-making, with the level of 93.1 dB(A) and 89.5 dB(A), respectively. Vibration existed in core-making and cast shakeout and finishing. Compulsory postures included long standing, seating and bowing.

CONCLUSIONOccupational hazards in environment of the foundry are diversified and their concentrations exceed permissible exposure limits stipulated by the national occupational hygienic standards. High-concentrations of dust, metal fume, low-concentrations of variety of chemicals, high-intensity of noise and vibration, heat stress, and harmful compulsory posture, and so on all co-exist in the foundry. Control and protective measures should be strengthened.

Singapore, an island republic of over 5 million inhabitants, has 3.1 million workers. Most are employed in the service, finance and tourist/transport industry. Significant numbers work in manufacturing, construction and heavy industry. Following a series of construction and shipyard accidents with multiple deaths in 2004, the government announced its intention to reduce workplace fatalities from 4.9 to 2.5 per 100,000 by 2015. There was strong political will to achieve this target. The strategic approaches were to build workplace safety and health (WSH) capabilities; implement legislative changes with enforcement; promote benefits of WSH and recognize best practices, and enhance partnership with stakeholders. The anticipated outcomes were to reduce workplace fatality and injury rates; have WSH as an integral part of business; and establish a progressive and pervasive WSH culture. With these measures, the workplace fatality rate declined from 4.9/100,000 in 2004, to 2.2/100,000 in 2010. However, other confounding factors could also account for this decline, and have to be considered. The next target, announced by Singapore's Prime Minister in 2008, is to further reduce the workplace fatality rate to 1.8/100,000 by 2018, and to have "one of the best workplace safety records in the world".
Accident Prevention ; Intention ; Metallurgy ; Practice Guidelines as Topic ; Singapore

The pure titanium disks were divided into three groups and etched for 30 minutes with HNO3, hot H2SO4/H2O2 or hot H2SO4/HCl respectively. The treated disks were studied and analyzed with scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). The disks etched with HNO3 had a smooth surface, while those etched with hot H2SO4/H2O2 or hot H2SO4/HCl had rough surfaces, and the surface etched with hot H2SO4/HCl had larger micropores. The XPS analysis demonstrated that the main elements of the surface in three groups were titanium, oxygen and carbon. The carbon concentration was the lowest on the surface etched with hot H2SO4/H2O2 and the highest on that etched with hot H2SO4/HCl. The substances were TiO2, Ti2O3, TiO and metal Ti on the surface etched with HNO3 or hot H2SO4/H2O2. Only TiO2 was detected on the surface etched with hot H2SO4/HCl.
Hydrochloric Acid ; Hydrogen Peroxide ; Metallurgy ; methods ; Nitric Acid ; Oxides ; Sulfuric Acids ; Surface Properties ; Titanium ; chemistry

OBJECTIVETo investigate the characteristics and changing trend of occupational hazards in the working environment of a foundry plant from 1987 to 2010.

METHODSThe foundry plant of a large-scale automobile company in Hubei Province, China was chosen as the study site. The data on occupational hazards in the working environment of the foundry plant in the past years were collected, and additional measurements were performed. The means and geometric means of the concentrations of occupational hazards were calculated. The characteristics and changing trend of occupational hazards from 1987 to 2010 were presented.

RESULTSThere were dust, chemical, and physical occupational hazards in the working environment of the foundry plant, with silica dust, noise, and heat stress as the main ones. Dust, mainly silica dust, is found in all aspects of foundry. The mean concentration of silica dust was high (3.2∼8.2 mg/m(3)), exceeding the national occupational exposure limit (1 mg/m(3)). The mean concentrations of silica dust varied across different types of work, with higher levels in cast shakeout and finishing, overhead crane operation, and sand preparation. The mean concentration of respirable dust in the foundry plant was low (0.38 mg/m(3)), not exceeding the national occupational exposure limit (0.7 mg/m(3)). There were high concentrations of grinding wheel dust (10.6 mg/m(3)) and welding fume (5.7 mg/m(3)) in cast shakeout and finishing, exceeding the national occupational exposure limit (8 and 4 mg/m(3)). Coal dust was mainly found in melting as well as cast shakeout and finishing, with higher concentration in the former (4.7 mg/m(3). The main chemical occupational hazard in the environment of the foundry plant was formaldehyde (1.23 mg/m(3)), exceeding the national occupational exposure limit (0.5 mg/m(3)). The concentrations of ammonia, phenol, metal fume, sulfur dioxide, hydrogen sulfide, and phosphine in the foundry plant were low. The mean concentration of polycyclic aromatic hydrocarbons was 0.1405 µg/m(3), with a higher level in pouring. The main physical occupational hazards in the working environment of the foundry plant were noise and heat stress. Noise, mainly steady noise, was distributed in all workshops of the foundry plant, with a mean intensity of 85.1 db (A). Noise levels varied across different types of work, higher in cast shakeout and finishing (89.3 db (A)) and moulding (85.4 db (A)). Heat stress mainly existed in overhead crane operation (35.1°C), pouring (33.3°C), and melting (32.8°C).

CONCLUSIONDust, chemical, and physical occupational hazards co-existed in the working environment of the foundry plant. High concentration of dust was widely distributed in many workshops and across many types of work, but the dust concentration showed a downward trend. Chemical occupational hazards included ammonia, phenol, hydrogen sulfide, and metal fume, most at low concentrations. High-intensity noise was widely distributed in all working positions of foundry process and mainly from equipment operation, collision between parts, and gas injection. High-intensity heat stress mainly existed in overhead crane operation, pouring, and melting.

The extreme microorganisms Ferroplasma spp., play an important role in bioleaching of sulphide ores at low pH value and temperatures around 50 degrees C. Without cell wall, Ferroplasma spp. is sensitive to pulp density, shearing force and heavy metal ions. Thus it is difficult to obtain their high cell density cultures, which limits the large-scale industrial application. In this paper, the optimum culture conditions of Ferroplasma thermophilum were studied by shaking culture. The results showed that the optimum culture conditions are as follows: 50 degrees C, initial pH 0.5, 50 mL working volume in 250 mL shaking-flask, inorganic nitrogen source (NH4)2SO4. The optimum combination of FeSO4.7H2O, yeast extract and peptone was determined by orthogonal experiments, including FeSO4.7H2O 40 g/L, yeast extract 0.3 g/L, peptone 0.2 g/L. Under the optimum culture conditions, the cell density was up to 6.3 x 10(7) cell/mL, and the oxidation of 40 g/L ferrous sulfate heptahydrate was finished in less than 72 hours. The results might provide information for scale-up of archaeon culture as well as its industrial application.
Archaea ; cytology ; growth & development ; Cell Culture Techniques ; methods ; Culture Media ; Hydrogen-Ion Concentration ; Metallurgy ; Temperature