What category of hazardous waste does HW21 belong to, and what is the category of hazardous waste of

HW21 is a hazardous waste containing chromium. According to the National Hazardous Waste List.

In the 2016 edition, it can be known that HW21 is a chromium-containing waste. It stipulates that there are two ** dust removal ash containing chromium, both of which are in the "HW21 chromium-containing waste" in the "ferroalloy smelting" industry. One is the hazardous waste of "dust collected by the dust collection (removal) device in the production process of chromium-iron-silicon alloy" ** is 315-001-21; The other is the hazardous waste ** of "dust collected by the dust collection (removal) device in the production process of ferrochrome alloy" is 315-002-21.

Chemical properties containing chromium:Chromium slowly dissolves in dilute hydrochloric acid.

dilute sulfuric acid, and produce a blue solution. When in contact with air, it turns green because it is oxidized to green CrCl3

cr + 2hcl= crcl2 + h2↑。

4crcl2 + 4hcl + o2= 4crcl3+ 2h2o。

Chromium with concentrated sulfuric acid.

reaction, sulfur dioxide is generated.

and chromium sulfate ( ) 2Cr + 6H2SO4 (concentrated) = Cr2 (SO4) 3 + 3SO2 + 6H2O.

But chromium is insoluble in concentrated nitric acid.

It is blunt due to the formation of a tight oxide film on the surface. At high temperatures, chromium can be combined with halogens.

Direct combination of sulfur, nitrogen, carbon, etc.

Chromium reacts with dilute sulfuric acid: Cr + H2SO4 = CrSO4 + H2.

According to the National Hazardous Waste Catalogue HW21 released in 2021, it is a chromium-containing waste.

HW 21 chromium-containing waste mainly comes from industries such as fur tanning and product processing, basic chemical raw material manufacturing, ferroalloy smelting, metal surface treatment and heat treatment, and electronic component manufacturing, including chrome tanning agents, retanning wastewater treatment sludge, and chrome-containing leather waste produced by leather cutting. Chromium slag, aluminum sludge, miscanthus salt, wastewater treatment sludge.

The dust collected by the dust removal device in the production process of ferrosilicon alloy, the dust collection device in the production process of iron-chromium alloy, the chromium leaching slag produced by chromium metal smelting, the chromium-containing waste liquid produced in the production process of chromic anhydride produced by sodium dichromate and concentrated sulfuric acid, the waste liquid produced by chromic acid anodizing, the pool slag and wastewater treatment sludge, and the waste residue and wastewater treatment sludge produced by chromic acid anodizing, etc.

Related Hazards

Chromium-containing waste is highly toxic. If not handled properly, it will pose a serious threat to the ecological environment and human health. The toxicity of chromium is closely related to the form in which it is present, as are the toxicity of different compounds of the same valent chromium.

Numerous studies have shown that hexavalent chromium is about 100 times more toxic than trivalent chromium. Hexavalent chromium exists in the form of anions, which are easily soluble in water and have strong oxidizing properties. It is the second largest heavy metal pollutant in the soil environment after lead.

It can cause a series of diseases to the human body through inhalation, ingestion or contact, such as edema, ulcers, lung cancer, etc. Trivalent chromium has teratogenic effects. The damage of chromium to surface water is mainly affected by its sensory and self-purification, and it can also kill plankton in the water, thereby affecting the self-cleaning ability of the water body and deteriorating the water quality.

In addition, the inhibition of plant growth by excess chromium is mainly due to the fact that chromium is not only harmful to the plant itself, but also interferes with the absorption and transport of other elements, thus disrupting the normal physiological activities of the plant.

Class HW49Hazardous wasteIt's other waste。Including wastewater treatment sludge and residue generated in the process of physical and chemical treatment of hazardous waste, liquid waste catalysts, and other inorganic chemical industries.

Waste activated carbon from the production process.

The collected soot contains or directly contaminates hazardous waste with waste packaging, containers, cleaning debris.

HW49 Dangerous Goods Description

HW49 hazardous wastes are silicon trichloride and silicon tetrachloride.

Waste activated carbon generated in the production process of the chemical industry, waste packaging containers contaminated with toxic and infected hazardous waste, and discarded lead-acid batteries.

Nickel-cadmium batteries, mercury oxide batteries, etc.

The hazards of HW49 hazardous wastes damage the ecological environment. Under the long-term infiltration and diffusion of rainwater and groundwater, hazardous wastes discharged and stored at will pollute water bodies and soils, and reduce the environmental function level of the region.

Affects human health. Hazardous wastes are poisoned through ingestion, inhalation, absorption, and eye contact, or cause dangerous events such as combustion, and long-term hazards include long-term poisoning, carcinogenicity, teratogenicity, and mutation caused by repeated contact.

constraints on sustainable development.

The pollution of air, water and soil caused by the non-treatment or non-standard treatment of hazardous waste will also become a restriction on economic activities.

bottlenecks.

Class HW49Hazardous wasteIt refers to other wastes, including wastewater treatment sludge and residues generated during the physicochemical treatment of hazardous wastes, wastes produced in teaching activities, discarded circuit boards, etc.

With the development of industry, the discharge of hazardous wastes from industrial production processes is increasing. It is estimated that 100 million tonnes of hazardous waste are generated worldwide each year. Due to the serious pollution and potential serious impact of hazardous waste, the public opposes the establishment of hazardous hail lead infiltration waste disposal sites in the areas where they live, and the high cost of hazardous waste disposal, some companies are trying to reach out to industrially underdeveloped countries and regions.

Transfer of hazardous waste.

Disposal:

1. Physical treatment: Physical treatment is to change solid waste by concentration or phase change.

The structure makes it a form that is convenient for transportation, storage, utilization or disposal, including compaction, crushing, sorting, thickening, adsorption, extraction and other methods.

2. Chemical treatment: chemical treatment is the use of chemical methods to destroy the harmful components in solid waste, so as to achieve harmlessness, or transform it into a form suitable for further treatment and disposal. The purpose is to change the chemical properties of the spine treatment substance.

Thus reducing its harmfulness. This is a commonly used pretreatment measure for hazardous waste before final disposal, and its treatment equipment is conventional chemical equipment.

The above content reference: Encyclopedia - Hazardous Waste.

HW17 stands for hazardous waste generated by metal surface treatment and heat treatment.

It is mainly used to treat sludge and wastewater produced by sensitization of stannous chloride, and zinc chloride is used.

Sludge and wastewater treatment sludge from sensitization of chlorhuhu-cracked ammonium, bath liquid, tank slag and wastewater treatment sludge from zinc and electroplating chemicals for galvanizing, etc.

Hazardous waste HW17 generally includes:

1. The electroplating tank slag and tank liquid in the electroplating industry are closed and water treatment sludge is closed;

2. Corrosive liquid, washing liquid and sludge generated by acid (alkali) washing, degreasing, rust removal and washing processes on metal and plastic surfaces;

3. Residues (liquids) and sludge generated in the process of phosphating, polishing and polishing on the surface of metals and plastics;

4. Waste liquid and residue generated in the process of coating stripping;

5. Waste electroplating solution, plating tank sludge, electroplating water treatment sludge, surface treatment acid and alkali slag, oxidation tank slag, phosphating slag, nitrite.

Waste residue and so on.

<> waste mineral oil has been included in the National Hazardous Waste List, numbered HW08. Waste mineral oil is a complex mixture of various substances, the main components of which are C15-C36 alkanes and polycyclic aromatic hydrocarbons.

PAHS), olefins, benzene series, phenols, etc.

Waste mineral oil is the oil that is replaced when the original physical and chemical properties can not be used due to the action of impurity pollution, oxidation and heat, which can no longer be used; It mainly comes from oil sludge and oil bumping feet produced by oil exploitation and refining; sediments generated during the storage of mineral oils; Oil residue and filter media in the process of replacing oil and regeneration of machinery, power, transportation and other equipment. According to the National Hazardous Waste List, it is a hazardous waste. It is mainly hydrocarbons with a relatively small number of carbon atoms.

substances, mostly unsaturated hydrocarbons. Its main ingredient is hydrocarbons, such as hydrocarbons such as chain lengths.

Stable performance.

1. Waste residue and wastewater treatment sludge produced by sensitization treatment of zinc chloride and ammonium chloride.

2. Waste tank liquid, tank slag and wastewater treatment sludge produced by zinc and electroplating chemicals for galvanizing.

3. Waste tank liquid, tank residue and wastewater treatment sludge produced by cadmium plating with cadmium and electroplating chemicals.

4. Waste tank liquid, tank slag and wastewater treatment sludge produced by nickel plating with nickel and electroplating chemicals.

5. Use nickel plating car brother liquid to treat sludge from waste tank liquid, tank slag and wastewater produced by nickel plating.

6. The waste tank liquid, tank residue and wastewater treatment sludge produced by using silver nitrate, alkali and formaldehyde for metal coating silver plating.

7. Waste tank liquid, tank slag and wastewater treatment sludge produced by gold plating with gold and electroplating chemicals.

8. Waste tank liquid, tank slag and wastewater treatment sludge produced by using copper plating solution for chemical copper plating.

9. Use palladium and tin salts for activation treatment of waste residue and wastewater treatment sludge produced in Zhouzhou.

10. Waste tank liquid, tank residue and wastewater treatment sludge produced by using chromium and electroplating chemicals for black chrome plating.

11. Use potassium permanganate to remove the waste residue and wastewater treatment sludge generated by drilling and degumming.

12. Waste tank liquid, tank slag and wastewater treatment sludge produced by copper plating with copper and electroplating chemicals.

13. Waste tank liquid, tank slag and wastewater treatment sludge generated by other electroplating processes.

14. Waste corrosion liquid, waste washing liquid, waste tank liquid, tank slag and wastewater treatment sludge produced by acid (alkali) washing, degreasing, rust removal, washing, phosphating, light and chemical polishing processes on the surface of metals and plastics.

15. Waste liquid, tank residue and wastewater treatment sludge generated in the process of coating stripping.

16. The waste residue and wastewater treatment sludge produced by the use of colloids, organic solvents and adhesives containing dichromate for vortex anti-corrosion coating.

17. Waste residue and wastewater treatment sludge produced by chemical hardening of resist layer using chromium compounds.

18. Use the waste tank liquid, tank residue and wastewater produced by chromium chromatic acid plating to treat sludge.

19. Waste tank liquid, tank residue and wastewater treatment sludge produced by using chromic acid for plastic surface roughening.