Abstract Booklet 2006 - Swanson School of Engineering - University ...

coke-oven gas) reforming was taken in a Plug Flow Reactor (PFR). The research
indicated that: 1) in the uncatalyzed CH 4 -H 2 O reforming, the conversion rate of CH 4 is
lower. At the reaction temperature of 1100°C the conversion rate is about a half.
However, in the carbon catalyzed CH 4 -H 2 O reforming, the conversion rate of CH 4 at
1100°C is 97.4%. The carbon catalyst can accelerate the reaction of CH 4 -H 2 O
reforming; 2) In the process of CH 4 -H 2 O reforming, the reaction of water gas shift
happened because of the existence of H 2 O and the component contents of the product
gas have been changed. At lower temperatures, the water gas shift reaction has the
trend of reduce the content of CO and increase the content of H 2 in the product gas; 3)
Because of the existence of water gas shift reaction, in the CH 4 -H 2 O reforming
reaction, as the ratio of H 2 O/CH 4 was towards 1, the content of methane in coke-oven
gas appeared towards highest; At 1200°C, with the staying time 0.5 seconds, the
methane conversion rate in carbon catalyzed reaction is 85.5%. When the resident time
lengthens to 1 second, the conversion rate of methane in coke-oven gas can reach
above 95.0%. 4) At the temperature about 1000°C carbon catalyst shows the catalytic
activity on water gas shift reaction. When the reaction temperature reaches above
1050°C, the amount of CO 2 will rapidly decrease to below 0.5%. This could be due to
that at the temperature, the reaction between C and CO 2 could rapidly increase, i.e. the
CO 2 from shifting reaction reacts with the C in catalyst, rapidly decreasing CO 2
contents. 5) The result of element analysis and specific surface area analysis of the
carbon catalyst indicated that the contents of S and N in the carbon catalyst decreased
sharply and the pore specific volume and the surface area increased after the reaction
of CH 4 -H 2 O reforming.
SESSION 52
ENVIRONMENTAL CONTROL TECHNOLOGIES: GENERAL TOPICS
52-1
Polycyclic Aromatic Hydrocarbon in Soil from Beijing, China
Xiaobai Xu, Ma Ling-Ling, Xu Xiao-bail, Li Xing-Hong, Chinese Academy of
Sciences, CHINA
Cheng Hang-Xin, Institute of Geophysical & Geochemical Exploration, CHINA
The rapid urbanization and industrialization of Beijing has resulted in significant stress
to Beijing environments. In the present study, 16 priority polycyclic aromatic
hydrocarbons (EPA-PAHs) in the surface soils from Beijing were determined using
gas chromatography and mass spectrometry (GC–MS). The total concentration of 16
EPA-PAH varied from 0.016 to 5.470 μg g -1 in soil of Beijing. The spatial distribution
of PAHs was displayed by the contour plot, which clearly showed that the sites with
higher content of PAHs are located in the urban areas and northwest outskirts and
those with lower content are distributed in the south and northeast outskirts.
Compounds profiles presented that the 4-, 5- and 6-ring PAHs were major
compositions and represented about 76%. It was worth noticing that the level of BaP,
the most potent carcinogenic PAHs, was from less than limits of detection to 0.402 μg
g -1 in soils. The correlation analysis showed that PAHs have the similar source in most
sampling sites and BaP might be considered as the indicator of total PAHs.
Characteristic ratios of PAHs indicated that the PAHs pollutants probably mainly came
from the pyrogenic origins, especially coal combustion and vehicular emission. The
level of PAHs in our study area was also compared with other studies. The information
from this study is significantly for understanding PAHs pollution in the environment of
integrated Beijing city.
52-2
Eco-Friendly Reclamation of Mine Spoil for Agro-Forestry
through Fly Ash and Biological Amendments
Lal Chand Ram, Nishant Srivastava, S.K. Jha, A.K. Sinha, Central Fuel Research
Institute, INDIA
The generation of huge quantities of mine spoil comprising unwanted shaly matter,
stones, etc. in the ratio (1:4, coal:mine spoil) produced from open cast coal mining
contributing about 70% of total coal extraction is a big challenge for environmental
managers apart from utilization of huge amount of fly ash (110 million tones/annum)
being generated from 85 thermal power plants (TPPs) in our country. Such problems of
management/disposal and utilization of mine spoil and fly ash will continue to
compound in near future in view of ever increasing demand of energy. As such the
development of an eco-friendly technology for reclamation of mine spoil through
amendment of fly ash will be of much significance. Fly ash being alkaline and
endowed with an excellent pozzolanic nature, silt loam texture, and plant nutrients, has
the potential to improve the texture, fertility and crop productivity of mine spoil.
Extensive field demonstration trials on the reclamation of mine spoils of Neyveli
Lignite Corporation (NLC), Tamil Nadu and Bharat Coking Coal Ltd., Dhanbad was
carried out for three years using fly ash from NLC and Santhaldih TPPs. For
agricultural purpose fly ash from NLC was applied at varying doses (@ 0, 5, 10, 20,
50, 100, 200 t/ha) alone and in combination with press mud and other amendments,
where repeat application was made up to 50 t/ha. For forestry plantations Santhaldih
TPP ash was applied at selective dose of fly ash with other amendments.
For agricultural application, the mine spoil area (6000 m 2 ) having a randomized block
design and 18 treatments (T1-T18), crop rotation (rice-green gram-rice-sun hemp-ricerice)
was selected. Biometric observation of the growth and development stages of rice
crops revealed that overall growth condition of rice plants was luxuriant, with less
incidence of pest, uniform and early maturity, intense colour of green leaves and
bigger size of panicle in the plots amended with fly ash alone and in combination with
press mud in one time and repeat applications. The crop yield (grain and straw) was
found to be increased in the range from 3.0 to 42.0% over corresponding control from
5 to 20 t/ha, however repeat applications of fly ash at lower dosages (up to 20 t/ha)
were more effective in increasing the yield apart from improvement in the texture and
fertility of mine spoil and the nutrient content of crop produce than the corresponding
one-time applications and repeat applications up to 50 t/ha. Some increase in the
content of trace and heavy metals and the level of g emitters in mine spoil and crop
produce was observed, but well within the permissible limits. The residual effect of fly
ash on succeeding crops was also encouraging in an eco-friendly manner. For forestry
plantations, about 6000 plants consisting 17 different species were planted on the mine
spoil/over burden dump (BCCL) along with fly ash and other amendments (cow dung,
coco peat, humic acid, biofertilizer, etc.) which evinced that the physico-chemical and
biological characteristics of mine spoil was significantly (p