Analysis and suggestions on the comprehensive util

Analysis and suggestions on the comprehensive utilization of desulfurization slag

analysis on the comprehensive utilization of desulfurization slag

(1) the composition of desulfurization slag is complex. The composition of desulfurization slag in daily glass enterprises is relatively complex, such as the high content of sodium fluoride. The specification and conditions for daily use glass industry (2017 version) stipulates that daily use glass production enterprises are prohibited from using fluorine-containing raw and auxiliary materials (except for all electric furnaces). Sodium fluoride (CAS No.:) is a toxic substance, which is identified according to the identification standard for hazardous wastes - Identification of toxic substances (GB 5085.) According to relevant regulations, when the total content of one or more toxic substances is ≥ 3%, this kind of solid waste belongs to hazardous waste. Therefore, in order to avoid desulfurization slag becoming hazardous waste, the use of fluorine-containing substances should be reduced from the source, or the desulfurization treatment process should be changed

(2) the level of comprehensive utilization is low. The comprehensive utilization of desulfurization slag mainly includes the production of gypsum board, gypsum block, gypsum powder, cement corrosion inhibitor, backfilling of mines, soil improvement, road construction, brick making, sludge neutralization, etc. some enterprises have also studied replacing some glass raw materials with semi dry desulfurization slag. But in general, the comprehensive utilization level of desulfurization slag is still low. By querying the national pollutant discharge permit management information platform (c3054, c3055, c3056), 231 enterprises (with furnaces) were selected, and only 36 enterprises reported the amount of desulfurization solid waste, accounting for 15.58%. The production of desulfurization solid waste is 21172.64t/a, the self utilization is 9432t/a, the self disposal is 377t/a, the entrusted utilization is 3608.99t/a, and the entrusted disposal is 7734.65t/a

(3) the treatment is not standardized. At present, the utilization, treatment and disposal measures of desulfurization slag that has not yet achieved comprehensive utilization are not standardized. For example, the desulfurization slag of some enterprises is stored by themselves, which is inconsistent with the entrusted utilization and disposal method of the sewage discharge permit application. The storage sites of desulfurized slag of some enterprises do not meet the relevant technical requirements of the standard for the storage and landfill pollution control of general industrial solid waste in order to prohibit the transfer of combustion chain (GB), and the anti leakage, anti loss, anti dispersion and other measures are not in place

suggestions

1. Promote the upgrading of cleaner production technology. Use clean fuels and raw materials to reduce the production of sulfur dioxide. Reduce the introduction of fluoride from the source. For example, nitrate and sulfate can be used in the clarifier instead of fluoride; phosphorus torsion meter can be used in the opacifier; the simpler the operation, the better acid salt, tin compound, etc.; boron compound, nitrate, etc. can be used in the flux

2. Strengthen the R & D and application of comprehensive utilization technology. Compared with the desulfurized gypsum produced in thermal power and other industries, the desulfurized slag in the glass industry has the characteristics of relatively small amount, scattered distribution and complex composition. The comprehensive utilization of Desulfurized Slag requires specific analysis of specific problems. According to the mature experience of European glass manufacturing enterprises, desulfurization slag can be used as glass raw materials. Some domestic flat glass and daily-use glass enterprises also explore the recycling of desulfurization slag in production. It is suggested to carry out R & D, application and promotion of key technologies such as reuse and recycling of desulfurization slag

3. Strengthen the guidance of environmental protection policies, regulations and standards. The current policies, regulations and standards have put forward certain requirements for desulfurization slag, but they are not comprehensive. For example, standards such as the design standard for flue gas desulfurization process (GB) and the slight decline of individual varieties in individual areas of flue gas desulfurization gypsum (gb/t) put forward quality requirements for anhydrous sodium sulfite and gypsum. The feasible technical guide for pollution prevention and control in glass manufacturing industry (HJ) puts forward the direction of comprehensive utilization of desulfurization slag, pointing out that desulfurization gypsum can be used as cement corrosion inhibitor or gypsum board, and can also be used to produce gypsum powder, gypsum block, backfill mine, improve soil, etc. according to its quality. The ash produced by semi dry desulfurization can be used for road construction, brick making, sludge neutralization, etc. In the policy documents related to the prevention and control of air pollution and solid waste pollution, we should further emphasize the environmental management requirements of desulfurization slag, and improve the attention of local ecological environment management departments and enterprises to the environmental management of desulfurization slag. According to the actual characteristics of desulfurization slag in daily glass industry, relevant comprehensive utilization technical specifications and by-product quality standards are formulated to standardize and improve its comprehensive utilization level

4. Strengthen the investigation and rectification of solid waste. According to the requirements of laws, regulations, policies and standards such as the law of the people's Republic of China on the prevention and control of environmental pollution by solid waste and the pollution control standard for the storage and landfill of general industrial solid waste (GB), we will carry out the screening and remediation of solid waste in the daily-use glass industry. According to the requirements of the notice on strengthening the identification of hazardous wastes (Exposure Draft) and other documents, we will focus on the identification of hazardous wastes. Check the production, storage and flow of desulfurization slag, and check the implementation of desulfurization slag pollution prevention measures and environmental compliance with the relevant requirements of enterprise environmental assessment and sewage discharge permit