This paper quantitatively investigates the compositions of the gaseous pollutants in the ambient air of a secondary fiber paper mill. Total volatile organic compounds (TVOC), formaldehyde (HCHO), sulfur compounds (H2S), and hydrocarbon compounds (CxHy) were analyzed on six sampling sites with photo-ionisation detector, acetylacetone spectrophotometric method, and gas detector. The results revealed that, the high levels of TVOC and CxHy were detected at the wet end of paper machine and the office area, respectively; all the H2S contents on the six sites exceeded the limit (0.06 mg m(-3)) seriously; the HCHO concentrations at other five sites were out of the limit (0.10 mg m(-3)) except for the wastewater treatment plant. Furthermore, the necessary discussions about the possible pollution sources were considered on the process flow, the chemical agents used, and the ambient conditions in the paper mill. For the sake of air pollution control in paper mills, these remarkable results and analysis lay some technical basis in the following researches that should attract more attentions.

In this paper, the deep-bed drying rate was analyzed under different bed depths and air temperatures. It was found that the bed depth had a greater impact on the drying efficiency, and if the initial moisture content of maize and the ventilation temperature are higher, the effect would be much more notable. The results will provide a basis for optimal design of the deep-bed drying devices.

The fiber of the agriculture and forestry biomass resources and the processing residues is main raw materials as a reinforcing material, the calcinated calcium sulfate hemihydrates by industrial flue gas desulfurization waste is a binder, adding efficient composite retarder to increase the initial setting time of gypsum and meet the production process requirements, adding conductive carbon black to reduce system resistance gypsum fiber to produce and meet the requirements of antistatic products. By semi-dry process, we produced the retardant, waterproof, environmental friendly and anti-static desulfurization gypsum fiberboard. Desulfurization gypsum antistatic fiberboard can meet the market demand for functional products used widely in antistatic floor, antistatic wall panel etc. The production of anti-static desulfhurization gypsum fiberboard expands the application range of desulfhurization gypsum, at the same time, which changes the structure of the forestry industry and has a positive effect on improving the forestry economic operation quality, efficiency and international competitiveness.