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Decomposition of trans -1,2-dichloroethylene( trans -DCE) in low-humidity air under electron beam irradiation at different initial concentrations has been investigated. CO, CO 2 were identified by TOC analyzer as inorganic products and cis -1,2-dichloroethylene was observed by GC-FID, while such compounds as CH 2 CHCl, CH 2 CCl 2 , CHClCCl 2 , CCl 2 CCl 2 , CH 2 ClCOCl were not found. Degradation efficiencies of trans -DCE and 1,1-DCE were compared and a mechanism of trans -DCE decomposition was proposed.

A study on electron-beam treatment was carried out to find out the effective decomposition conditions of vaporized volatile organic compounds. Air streams containing aromatic and aliphatic compounds were irradiated with electron beams in batch and flow systems. The research showed that chloroethene was readily decomposed through a chain reaction with one of the fragmentation products, Cl radical. A thermal electron and negative oxygen ion were important active species for decomposing carbon tetrachloride. The formation of particles was observed only from the irradiation of aromatics, like benzene, xylene, and chlorobenzene. Dechlorination of chlorobenzene was enhanced in the presence of ammonia.

Decomposition of 1,1-dichloroethylene (DCE) in humid air under electron beam irradiation has been investigated in the experiment. Inorganic compounds (CO, CO 2 ) and chloroacetyl chloride (CH 2 ClCOCl) were observed as main products. Modeling simulation was carried out by using computer code Kinetic (Bugaenko and Grichkin, Report ITEP 50, (1980) 1–19) and Gear method. 80 different species and 319 relevant reactions were considered. Calculation results agree well with the experiment. A possible reaction mechanism is proposed in this work. Cl − dissociative secondary electron attachment, oxygen negative ions and fast charge transfer of ionized carrier gas ions predominate in the initial stage of 1,1-DCE decomposition, while Cl radicals become significant after milliseconds’ irradiation.

Electron beam irradiation of trans - and cis -1,2-dichloroethylenes ( cis -DCEs)-air mixtures was carried out in order to get quantitative information on chain oxidation. Decomposition of cis -DCE was initiated by OH, O( 3 P) radicals, and thermal electrons and proceeded by Cl radical chain oxidation, whereas that of trans -DCE was initiated by not only the radicals and the electrons but also O 3 . The chain lengths of trans -DCE by O 3 were estimated to be 6.2±0.2 independently of trans -DCE and O 3 concentrations. The decomposition mechanism was also clarified.

Research on electron beam decomposition of volatile organic compounds (VOCs) in air was carried out to establish an advanced treatment technology for industrial off-gases. Benzene, toluene and o -xylene were selected as aromatic VOCs and dichloro-, trichloro- and tetrachloro-ethylene as chloroethenes. The experimental results showed that G-values of decomposition ranged from 1.0–2.2 in aromatic compounds and 30–60% of decomposed compounds were converted into aerosols. On the other hand, G-values of decomposition of chloroethenes increased with the initial concentration and number of chlorine atoms in a molecule, for example, the G-value at 180 and 1580 ppm of tetrachloroethylene were 22 and 172, respectively. The formation of aerosol was not observed in the decomposition of chloroethenes. An application of low energy electron accelerator for treatment of exhaust gases containing VOCs was also discussed.

To get qualitative and quantitative data for the decomposition of chlorinated hydrocarbons, gaseous chlorobenzene of 10–40 ppm concentrations was irradiated under air condition with electron beam in the dose range of 0–10 kGy. The irradiation decomposed chlorobenzene, and formed gaseous products and aerosols. An irradiation dose of 10 kGy decomposed 80% of chlorobenzene at 10 ppm. Good mass balances on chorine (mgCl) and carbon (mgC) were obtained at doses of 4, 8 and 4 kGy with the addition of NH 3 . About 65% of chlorine in reacted chlorobenzene was dechlorinated by the irradiation at 4 and 8 kGy. The addition of NH 3 enhanced the dechlorination to about 80%. At least about 40% of the gaseous products was found to be aliphatic oxygenates like formate, acetate and α -ketoglutarate at doses of 4 and 8 kGy on the basis of carbon unit (mgC). These aliphatic oxygenates accounted for only 3% in the case of the aerosols. The FTIR analyses revealed that the aerosols consisted of low-vapor-pressured products that had nitrate groups and/or retained the aromatic ring.

Decomposition of tetrachloroethylene and other chloroethenes in electron beam irradiation were examined in order to get information on treatment of industrial off-gas. The G-values of decomposition were larger in the order of tetrachloro->trichloro-> trans -dichloro-> cis -dichloro->monochloro-ethylene. For tetrachloroethylene, the effect of initial concentration on G-value of decomposition was also examined. The G-values of decomposition increased with the initial concentration. Decomposition mechanism and the difference in G-values of decomposition between trans - and cis -dichloroethylene were discussed.

Experiments were carried out to investigate the removals of SO2 and NOx from simulated lignite-burning flue gas containing SO2 (4800 ppm), NO (320 ppm) and H2O (22%) by electron beam irradiation. Removal efficiencies of SO2 and NOx were achieved to reach 97 and 88% at 70°C, and 74 and 85% at 80°C, respectively, with the dose of 10.3 kGy without NH3 leakage. The higher removal efficiencies of SO2 and NOx were observed in simulated lignite-burning flue gas than in coal-fired flue gas containing 800 ppm of SO2, 225 ppm of NO and 7.5% H2O at the same treatment condition. The higher removal efficiencies were attributed to the higher concentrations of SO2, H2O, and added NH3. Simulation calculations indicated that the higher concentrations of these components enhance the effective radical reactions to oxidize NO to form NO2 with HO2 radical, and to oxidize SO2 to form SO3 with OH radical and O2. The reactions of NOx with N and NH2 radicals to produce N2 and N2O also promote the NOx removal. By-product was determined to be the mixture of (NH4)2SO4 and NH4NO3 containing a small amount of H2SO4.

The results of reliable and precise measurement of gas composition in different key points of e-beam installation are necessary for its proper operation and control. Only the composition of flue gas coming into installation is adequate to composition of flue gas emitted from coal-fired boiler. At other points of e-b installation the gas composition is strongly modified by process conditions therefore specific measuring system (sampling and conditioning system and set of gas analyzers) for its determination are required. In the paper system for gas composition measurement at inlet and outlet of e-b installation are described. Process parameters are continuously monitoring by CEM system and occasionally by the grab sample system. Both system have been tested at pilot plant at EPS Kawȩczyn.

A pilot-scale test for electron beam treatment of flue gas (12,000m3N/hr) from coal-fired boiler was conducted by Japan Atomic Energy Research Institute, Chubu Electric Power Company and Ebara Corporation, in the site of Shin-Nagoya Thermal Power Plant in Nagoya, Japan. During 14 months operation, it was proved that the method is possible to remove SO2 and NOX simultaneously in wide concentration range of SO2 (250–2,000ppm) and NOX (140–240ppm) with higher efficiency than the conventional methods, with appropriate operation conditions (dose, temperature etc.). The pilot plant was easily operated with well controllability and durability, and was operated for long period of time without serious problems. The byproduct, ammonium sulfate and ammonium nitrate, produced by the treatment was proved to be a nitrogenous fertilizer with excellent quality.

The production of animal feeds and mushrooms from oil palm cellulosic wasres by radiation and fermentation has been investigated in order to utilize the agro-resources and to reduce the smoke pollution. The process is as follows: decontamination of microorganisms in fermentation media of empty fruit bunch of oil palm (EFB) by irradiation, inoculation of useful fungi, and subsequently production of proteins and edible mushrooms. The dose of 25 kGy was required for the sterilization of contaminating bacteria whereas the dose of 10 kGy was enough to eliminate the fungi. Among many kinds of fungi tested, C. cinereus and P. sajor-caju were selected as the most suitable microorganism for the fermentation of EFB. The protein content of the product increased to 13 % and the crude fiber content decreased to 20% after 30 days of incubation with C. cinereus at 30°C in solid state fermentation. P. sajor-caju was suitable for the mushroom production on EFB with rice bran.

In solid state fermentation, Pleurotus sajor-caju has been found to be able to degrade at least 30% oil palm empty Fruit Bunch (EFB) fibre leaving 70 % useful materials. Conditions under which fermentation carried out were investigated. It was found that, in the temperature range between 25– 28 °C, relative ph between 6–8, moisture between 60–70 % and medium composition of CaCO 3 : rice bran 2 %: 5 % were the optimum conditions. The results showed in fermented products that, there were substantial reduction in cellulosic component such as Crude Fiber (CF, 18 %); Acid Detergent Fibre (ADF, 45 %), Neutral Detergent Fibre (NDF, 61 %) and Acid Detergent Lignin (ADL, 14 %). However, Crude Protein (CP, 10%) increased resulted from single cell protein enrichment of mycelial microbial mass. The mass reductions of substrate in fermentation process corresponds to the CO 2 released during fermentation. Hence, attributable to the decreased in content of CF, ADF, NDF, and ADL. The digestibility study has also been carried out to determine the useful level of this product to ruminant. Aflatoxin content was detected low in both the initial substrates and products. Based on nutritional value and low content of aflatoxin, the product is useful as a source of roughage to ruminant.