JB/T 6047-1992 Method for harmless treatment of hazardous solid wastes by heat treatment salt bath
Some standard content:
Machinery Industry Standard of the People's Republic of China
JB/T 6047-1992
Harmful solid waste from thermal treatment of salt bath
Harmless treatment method
Published on May 5, 1992
Ministry of Machinery Industry of the People's Republic of China
Implementation on July 7, 1993
Machinery Industry Standard of the People's Republic of China
Harmful solid waste from thermal treatment of salt bath
Harmless treatment method
Subject content and scope of application
This standard specifies the chemical treatment process and safety technical requirements for hazardous solid waste from thermal treatment of salt bath. This standard applies to the harmless treatment of hazardous solid wastes from thermal treatment salt baths. Reference Standards
GB7487
ZB Z70 001
Basic Methods
Isonicotinic Acid-Pyrazolone Colorimetric Method
JB/T 60471992
Harmless Treatment of Barium Salt Residues, Nitrate Salt Residues and Cyanide Salt Residues. General Provisions for Pollution Management of Hazardous Solid Wastes from Thermal Treatment Salt Baths Chemical precipitation method and oxidation method are used to harmlessly treat three types of waste residues from thermal treatment salt baths. Types and sources of waste residues from salt baths (see Table 1). 3.1
Barium salt slag
Nitrate salt slag inspection
Cyanide salt slag
Barium salt slag treatment
High and medium temperature salt bath
Isothermal, graded annealing and tempering salt bath
Carburizing, liquid carburizing, nitrocarburizing, sulfur-ammonia carburizing, sulfur-ammonia carburizing, carburizing and other salt baths adopt the precipitation Ba2+ method, adding precipitant Na,SO or Na,CO,+H,SO4 to convert soluble toxic barium salts into non-toxic barium sulfate precipitates that are difficult to dissolve in water. The chemical reaction formula is as follows: BaCl+Na,SO-BaSO,+2NaCl
BaCl+Na,CO,+H,SO.+Baso+ +2NaCl+CO,t +H,o3.3 Nitrate slag treatment
（2）
Use the oxidation method and add the oxidant NaCIO to oxidize the toxic nitrite that is easily soluble in water into a non-toxic nitrate solution. The chemical reaction formula is as follows:
NaNO, + NaCIO-→ NaNO,+NaCI.-3.4 Cyanide slag treatment
（3）
Use the Fe2+ complexation and Fe+ direct reaction method and add iron salt to treat, first oxidize the cyanide into ferrocyanide, then oxidize it and finally transform it into a non-toxic ferrocyanide precipitate. The chemical reaction formula is as follows: 6NaCN+FeSO,→+Na.Fe(CN)+NaSO, Approved by the Ministry of Machinery and Electronics Industry on May 5, 1992 (4) Implemented on July 7, 1993 Salt bath waste slag treatment process JB/T6047-1992 3Na,Fe (CN) + 4FeCl,→+Fe.[Fe (CN) 6l, + +12NaCI 4.1 Salt bath waste slag treatment process flow 4.1.1 The waste slag pretreatment process flow is shown in Figure 1. Waste slag collection Barium chloride or sodium nitrite or sodium cyanide Harmful components Content determination Barium salt slag leachate treatment process flow is shown in Figure 2. Crushing
Leachate
To be treated
a. Precipitant: sodium carbonate + sulfuric acid
Leachate
[Ba\] content determination
Leachate
[Ba'\] content determination
Add precipitating agent 5%
Na,CO·10H,O aqueous solution
Precipitate (BasO.)
b. Precipitant: sodium sulfate
Add precipitating agent 2%
Residue one
Use sulfuric acid (1:5)
Adjust to the pH value of 6~7
Na,SO,·10HO aqueous solution
Precipitate (BaSO,)
The process flow of nitrate salt slag leachate treatment is shown in Figure 3. Precipitation
Nitrite
Leachate
[NO,] content determination
JB/T 60471992
Use hydrochloric acid (1:5)
Adjust the solution to 6.5≤pH≤8
Discharge or recycle for reuse
The cyanide salt slag leachate treatment process is shown in Figure 4. Cyanide
Leaching solution
Filter residue Fe,[Fe(CN)l
4.2 Treatment equipment
Add quantitative complexing agent
FeSO,·7H,Owww.bzxz.net
Oxidation reaction
Add quantitative oxidizing agent
Use hydrochloric acid (1:5)
Adjust to solution pH=4~5
Add precipitant 25%
FeCl,·6H,O aqueous solution
[CN-] content determination
Pulverizer, mixer, slag tank, filter, liquid storage tank, treatment tank (tank).
Materials or reagents are shown in Table 2.
Sodium hydroxide
Sodium hypochlorite
Sodium sulfate
Sodium carbonate
Ferrous sulfate
Ferrous chloride
Molecular formula
Na.SO, ·10H.0
Na,CO, ·10H.O
FeSO,·7H,O
FeCl, ? 6H,0
The treatment conditions of salt bath waste residue are shown in Table 3.
Industrial grade (density 1.84)
Industrial grade (density 1.19)
Industrial grade
Density 1.1 (containing 12.5% effective chlorine)
Industrial grade
Industrial grade
Industrial grade
Industrial grade
Particle size (mesh)
Solid-liquid ratio
(slag weight: water weight)
Dissolution method
Acidity and alkalinity of leachate
Amount of precipitant or oxidant added
Ratio to the content of harmful substances
Precipitation or oxidation
Reaction time h
Processing temperature ℃
Safety technical requirements
JB/T 6047-1992
Salt slag
1. Leaching for more than 20h, or
2. Heating and boiling for 1-2h, or
3. Stirring for 8h
6≤pH≤7
Na,SO,·10H,O (or
Na,CO, · 10H,o)
BaCL, is 1.5 : 1~2 : 1
Waste slag types
Nitrate salt slag
6≤pH≤8
NaCIO : NaNO
is 1.2:1~2:1
25±10
Cyanide slag
pH≥8 (adjusted with NaOH)
1. Leach for more than 20h
2. Stir for 4h
4≤pH≤5
FeCl, · 6H,o: NaCN
is 3:1~4:1
When crushing and treating waste slag (especially cyanide slag), it must be carried out in a factory or workshop with ventilation ducts, exhaust, dust collection, and wet storage equipment.
The treatment equipment or container must be covered to prevent leakage, corrosion, and strictly prevent the loss of toxic substances. Operators must strictly pay attention to safety protection 5.2
5.3 Residues and treated waste liquids shall be sampled and tested in batches according to the specified analysis method. The content of pollutants (Ba2+, NO,, CN) shall comply with the provisions of ZBZ71001 before they can be discharged. 6
Analysis of harmful substances
The analysis method of lock salt and nitrite shall be carried out in accordance with the provisions of Appendix A (reference) of ZBZ71001. The analysis method of cyanide shall be carried out in accordance with the provisions of GB7487. Additional notes:
This standard is proposed and managed by the Mechanical Industry Environmental Protection Technology Research Institute of the Ministry of Machinery and Electronics Industry. This standard is drafted by the Mechanical Industry Environmental Protection Technology Research Institute of the Ministry of Machinery and Electronics Industry. The main drafters of this standard are Zhang Wenlian and Wu Xinzhong. People's Republic of China
Mechanical Industry Standard
Harmful Solid Waste in Heat Treatment Salt Bath
Harmless Treatment Method
JB/T 60471992
Published by the Mechanical Science Research Institute
Printed by the Mechanical Science Research Institute
(No. 2, Shouti South Road, Beijing
Postal Code 100044)
Format 880×12301/16
Printing Sheet 1/2Number of Words 8.000
First edition in January 1993
First printing in January 1993
Print run 1-500
Price 5.00 yuan
Mechanical Industry Standard Service Network: http://www.JB.ac.cn661_09 /
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.