Promotion of Cleaner Production Technology in China's Chemical Industry (I)     

China's Ministry of Industry and Information Technology (MIIT) is encouraging the application and promotion of cleaner production technology to enhance the nation's cleaner production overall level. It also sets the energy conservation and emissions reduction goals for key sectors of China's chemical industry.

PVC sector

By 2012, the polyvinyl chloride (PVC) sector should use low-mercury catalyst in 50% of its calcium carbide-process PVC capacity, reduce the use of mercury by 208 tons per year, and recover all waste mercury catalyst. It should use the hydrochloric acid deep desorption technology into over 50% of its PVC capacity and dispose 250 000 tons of waste hydrochloric acid a year. It should utilize all the calcium carbide slag and reduce the calcium carbide slag discharge by 12.58 million tons; and reduce wastewater discharge to 42.3 million tons per year, or down by 39.9 million tons; reduce COD emissions to 5 770 tons a year, or down by 13 460 tons; and save 2 million tons of standard coal.
   And by 2012, the PVC sector should increase 2.6 million t/a dry-acetylene-process PVC producing capacity by newly building or renovating and build 7.8 million t/a dry-process cement plants as supporting facilities of the former; complete 36 million t/a polymerizing mother liquor wastewater treatment projects; dispose 50% or more of mercury-containing wastewater with sodium hydrosulfide and combining the hydrochloric acid deep desorption technology; and further promote the pressure swing adsorption technology in the treatment of distillation tail gas.
   The PVC sector should promote the integration of the low-mercury catalyst process for vinyl chloride production and the oxygen-controlled dry distillation technology for the recovery of HgCl2 and activated carbon in waste catalysts. By 2012, the prevalence rate of low-mercury catalyst in China's vinyl chloride capacity should reach 50%, the mercury consumption per ton of PVC should decline by 25%, and mercury emissions should be reduced by more than 50%. All the mercury-containing activated carbon generated by the PVC sector should be recovered.

MSG sector

By 2012, the average energy consumption per ton of monosodium glutamate (MSG) should drop to about 1.7 tons of standard coal, down by 10.5% compared to 2009. The MSG sector should reduce the energy consumption by 520 000 tons of standard coal per year, reduce the freshwater consumption to 110 million tons per year, the corn consumption to 4.25 million tons a year and wastewater emissions to 105 million tons per year, or down by 70 million tons per year; and reduce COD emissions by 1.59 million tons per year, ammonia nitrogen emissions by 44 800 tons per year, sulfuric acid consumption by 816 000 tons a year and liquid ammonia consumption by about 160 000 tons a year.

Citric acid sector

By 2012, the average energy consumption per ton of citric acid should drop to 1.57 tons of standard coal, down by 13.7% compared to 2009. The citric acid sector should reduce the energy consumption by 250 000 tons of standard coal per year; reduce fresh water consumption to 40 million tons a year and wastewater emissions to 35 million tons a year, or down by 20 million tons a year; and reduce sulfuric acid consumption by 720 000 tons a year, calcium carbonate consumption by 720 000 tons a year, calcium sulfate discharge by 960 000 tons a year and CO2 emissions by 384 000 tons a year.

Soda ash sector

By 2012, 50% of ammonia-soda enterprises should use the soda residue for the wet desulphurization of boiler flue gas and co-operate with enterprises from other industries at this aspect. The Hou's process soda ash capacity using the non-cooling carbonization technology should be raised up to 1 million t/a. More than 20% of Hou's process enterprises that make carbon dioxide from natural gas should recover CO2 from boiler flue gas and use it into soda ash production. The soda ash capacity using the dry distillation technology should be increased to 1.6 million t/a. The soda ash capacity using the transmission gas from cleaning outer coolers carbonization towers to make soda ash should be raised up to 1 million t/a.
   By 2012, the comprehensive utilization level of steamed ammonia residue from ammonia-soda plants should be increased to about 10%, and related ammonia consumption should be reduced to 3-4 kilogram per ton of soda ash. Hou's process plants should reduce their average wastewater emissions to 2 cubic meters per ton of soda ash and their ammonia consumption to 340-350 kilogram per ton of soda ash. The soda ash sector should totally reduce slag discharge by 160 000 tons, ammonia consumption by 95 600 tons and wastewater emissions by 17.34 million cubic meters.

Nitrogenous fertilizer sector

By 2012, the wastewater discharge of natural gas-based synthetic ammonia enterprises should be reduced to about 10 cubic meters per ton of ammonia (for advanced enterprises, it should be less than 5 cubic meters per ton of ammonia); for coal-based ones, it should be reduced to about 22 cubic meters per ton of ammonia (for advanced ones, it should be less than 8 cubic meters per ton of ammonia). The entire sector should reduce wastewater discharge by 15% or 200 million cubic meters, and reduce major pollutants emissions by 15%, that is, reducing ammonia-nitrogen emissions by 11 000 tons and COD emissions by 23 000 tons. For the fixed-bed batch gas-making process using coal as the raw material, 100% of heat in the discharged blowing gas should be recovered, and 100% of gasifier slag should be utilized. More than half of urea granulation towers should be equipped with dust recovery units.
   Two hundred enterprises with a total ammonia producing capacity of about 24 million t/a will be demanded to carry out technological renovations to achieve the zero discharge of wastewater in nitrogenous fertilizer production. More than 60% of them will have such technological renovations. Meanwhile, enterprises located in water-deficiency areas will be required to carry out "the ultra-low cooling water discharge technological transformation" to achieve the ultra-low wastewater discharge in nitrogenous fertilizer production. Over 80% of them will have such technological transformations. One hundred enterprises with a total ammonia producing capacity of about 12 million t/a will be demanded to carry out cleaner production technological renovations for the treatment and comprehensive utilization of waste gases and waste solids. Over 60% of them will have such technological transformations. For 20 enterprises with a synthetic ammonia capacity of over 200 000 t/a each, their raw materials, that is, natural gas and smoke-free lump coal, are in short supply. For those with available coal resources in a relatively short distance, they can use continuous pressurized coal gasification technologies (including the multi-nozzle water-coal slurry gasification technology, economical entrained flow classified gasification technology and HT-L space heater pulverized coal gasification technology) to transform their raw materials mix. This can add another 6 million t/a high-quality capacity. China will support 100 enterprises to use the room-temperature refined desulfurization technology and decarbonylation, metal-removal, dechlorination, ammonia-removal and oil-removal technologies to carry out deep gas purification technological innovations. More than 60% of them will adopt these technologies. China will support 100 coal-based synthetic ammonia enterprises to carry out cleaner production technological renovations to remove trace CO and CO2 in feedstock gas with the alcohol alkylation. More than 60% of them will remove trace CO and CO2 to achieve cleaner