How to deal with chemical experiments?
1, treatment of copper-containing waste liquid
The copper sulfate waste liquid used in the experiment was recovered by adding an appropriate amount of iron powder, and the mother liquor was precipitated, filtered and diluted.
2. Disposal of waste liquid containing mercury
Discharge standard: The maximum allowable discharge concentration of mercury in waste liquid is 0.05mg/L (unit: Hg).
Treatment method: sulfide precipitation method: firstly, adjust the pH value of waste liquid containing mercury salt to 8- 10, and then add excessive Na2S to generate HgS precipitation. Then FeS04(*** precipitant) is added to react with excess S2- to generate FeS precipitate, and the hard-to-precipitate HgS particles suspended in water are adsorbed and precipitated. Then, after standing, separation, centrifugation and filtration, the mercury content in the filtrate can be reduced to below 0.05 mg/L. ..
Reduction method: using waste copper, iron filings, zinc particles and sodium borohydride as reducing agents, metallic mercury can be directly recovered.
3. Treatment of waste liquid containing cadmium
Hydroxide precipitation method: add lime to the cadmium-containing waste liquid, adjust the pH value to above 10.5, fully stir and stand to make cadmium ions become insoluble Cd(OH)2 precipitation. Separate the precipitate, detect cadmium ions in the filtrate by dithizone spectrophotometry (down to below 0. 1mg/L), neutralize the filtrate to pH 7 or so, and then discharge.
Ion exchange method: Cd2+ ion has stronger binding force with cation exchange resin than other ions in water.
4. Treatment of waste liquid containing lead
Adding slaked lime to the waste liquid to adjust the pH value to be greater than 1 1, so that the lead in the waste liquid generates Pb(OH)2 precipitation. Then add Al2(S04)3 (coagulant) to reduce the pH value to 7-8, so that Pb(OH)2 and Al (OH) 3 * * precipitate, and separate the precipitate.
5. Disposal of arsenic-containing waste liquid
FeCl3 _ 3 _ 3 was added to the arsenic-containing waste liquid to make the Fe/As ratio reach 50, and then the pH value of the waste liquid was controlled at 8- 10 with hydrated lime. Arsenic in waste liquid is removed by composite precipitation and adsorption of newborn hydroxide and arsenic. Standing overnight, separating the precipitate, and discharging the waste liquid after reaching the standard.
6. Treatment of waste liquid containing phenol
Phenol is a highly toxic cell protoplasm poison. Treatment: Low-concentration waste liquid containing phenol can be boiled with sodium hypochlorite or bleaching powder to decompose phenol into carbon dioxide and water. If it is a high-concentration phenol-containing waste liquid, it can be extracted with butyl acetate, then back-extracted with a small amount of sodium hydroxide solution, distilled and recovered after adjusting the pH value, and the treated waste liquid is discharged.
7. Comprehensive treatment of waste liquid
Adjust the PH value of the waste liquid to 3-4 with acid and alkali, add iron powder, stir for 30min, then adjust the p H value to about 9 with alkali, continue stirring for 65438+/-00min, add aluminum sulfate or basic aluminum chloride coagulant for coagulation and precipitation, and the supernatant can be directly discharged and precipitated in waste residue.
8. Treatment of chromium-containing waste liquid
Reducing agents, such as ferrous sulfate, sodium sulfite and iron filings, are added to the chromium-containing waste liquid, and hexavalent chromium is reduced to trivalent chromium under acidic conditions, and then alkali, such as sodium hydroxide, calcium hydroxide and sodium carbonate, is added to precipitate trivalent chromium, and the clear liquid can be discharged. After the precipitation is dried, it can be roasted together with the cinder, and then it can be buried.
9. Treatment of cyanide-containing waste liquid
Low concentration waste liquid can be adjusted to PH above 10 by adding sodium hydroxide, and then potassium permanganate powder (3%) can be added to decompose cyanide. If the concentration is high, it can be treated with alkali chlorination. Firstly, adjust the PH value to above 10 with alkali, and then add sodium hypochlorite or bleaching powder. After full challenge, the hydride was decomposed into carbon dioxide and nitrogen, and was discharged after standing for 24 hours. Cyanide-containing fees shall not be dumped or mixed with acid, and the generated volatile hydrogen cyanide gas is highly toxic.
10, chloroform recovery
Wash chloroform waste liquid with water, concentrated sulfuric acid (one tenth of chloroform), pure water and hydroxylamine hydrochloride solution (0.5% AR) at one time. Washing with heavy distilled water twice, dehydrating the washed chloroform with sewage calcium chloride, standing for a few days, filtering and distilling. The distillation speed is 1~2 drops per second, and the distillate with boiling range of 60~62 degrees Celsius (under the frame) is collected and stored in brown reagent bottle (rubber plugs are not allowed).
1 1. Matters needing attention in laboratory waste liquid treatment
1). Try to recover the solvent and reuse it without disturbing the experiment.
2) For the convenience of treatment, its collection and classification are often divided into: a) combustible substances b) nonflammable substances c).
Aqueous waste liquid d) solid matter, etc.
3). Water-soluble substances are easily lost in the form of aqueous solution. So pay attention to recycling. However, solvents such as methanol, ethanol and acetic acid are easily decomposed by bacteria. Therefore, the dilute solution of this kind of solvent can be discharged after being diluted with a lot of water.
4). Waste liquid containing heavy metals should be treated as inorganic waste liquid after its organic matter is decomposed.
12, biological laboratory waste liquid treatment
The waste liquid pollution produced by biological laboratory is mainly chemical pollution, biological pollution and radioactive pollution. Chemical pollution includes organic pollution and inorganic pollution. Organic pollution mainly includes organic reagent pollution and organic sample pollution. In most cases, the organic reagents in the laboratory are not directly involved in the reaction, but only used as solvents, so the consumed organic reagents are discharged into the surrounding environment in various forms, and the total amount of discharge is roughly equivalent to the consumption of reagents. Day after day, year after year, the emissions are considerable. The pollution of organic samples includes some highly toxic organic samples, such as pesticides, benzo (α) pyrene, aflatoxin and nitrosamines. Inorganic pollution includes strong acid and alkali pollution, heavy metal pollution and cyanide pollution. Among them, heavy metals such as mercury, arsenic, lead, cadmium and chromium are not only toxic, but also accumulative in human body.
Biological pollution includes biological waste pollution and biological bacterial toxin pollution. Biological wastes include laboratory specimens, such as blood, urine, feces, sputum and vomit; Inspection supplies, such as experimental equipment, bacterial culture medium and bacterial positive specimens. Imperfect design of ventilation equipment in biological laboratory or personal safety protection loopholes in the experimental process will spread biological bacterial toxins, bring pollution and even bring serious adverse consequences. After the outbreak of SARS in 2003, many biological laboratories strengthened their research on SAS virus, and most of the SARS-infected people reported later were infected by researchers during laboratory research.
Regulations on the management of laboratory wastes
1. Laboratory wastes refer to the three wastes (waste gas, waste liquid and solid waste), residues of highly toxic substances (narcotic drugs and drugs) used in experiments, radioactive wastes and the corpses and organs of experimental animals.
Second, experimental teachers and technicians must establish awareness of environmental protection, strictly abide by the relevant provisions of the national environmental protection work, and students entering the laboratory must implement the principles and regulations of waste disposal.
Publicity and education.
Three, three wastes (waste gas, waste liquid, waste residue) treatment of general provisions:
1, exhaust gas
The laboratory should have a fume hood that meets the ventilation requirements. Experiments that produce a small amount of harmful waste gas should be carried out in a fume hood, and experiments that produce a large amount of harmful and toxic gases must have absorption or treatment devices.
2. Waste liquid
School laboratory waste liquid refers to all kinds of waste liquid mainly from chemical laboratory, biochemical laboratory and physical laboratory, or school practice place. General laboratory waste liquid can be divided into: ①
Organic solvent waste liquid (such as toluene, ethanol, glacial acetic acid, halogenated organic solvent waste liquid, etc.). ); ② Inorganic solvent waste liquid (such as heavy metal waste liquid, mercury-containing waste liquid, waste acid, waste lye, etc.). ). During the experiment,
Do not pour harmful and toxic waste liquid into the sink and drainage pipe at will. Compatibility tests should be carried out before different waste liquids are poured into waste liquid barrels, and they should be poured into corresponding waste liquid collection barrels according to label instructions.
It is forbidden to mix incompatible waste liquids in the same waste liquid barrel to prevent chemical reaction and explosion. Close the lid immediately after dumping the waste liquid. Especially the waste liquid containing heavy metals, regardless of its concentration, must be completely recovered.
3, waste residue, waste solid
Don't bury or discard harmful and toxic waste residue and solid waste at will, but put it in a special collection bucket. Empty containers and packages of dangerous goods must be thoroughly removed before they can be used for other purposes or discarded.
Four, experimental animal carcasses storage, incineration management regulations:
1, after the live animal experiment, animal carcasses or organs shall not be discarded at will, but must be collected in a unified way, frozen and stored in a centralized way, and burned regularly.
2. Any unit that stores animal carcasses shall carefully fill in the registration records, including the storage unit, the name of the depositor, the storage time, the species and quantity of animals, whether they are polluted, the type and degree of pollutants, etc.
3 experimental animal carcasses should be regularly cleaned, disinfected and burned by special personnel, and should not be overstocked or placed indoors.
Five, experimental toxic substances (narcotic drugs, drugs) and radioactive waste disposal regulations:
1. Residues of highly toxic substances (narcotic drugs and drugs) used in experiments or expired highly toxic substances shall be kept by laboratories, properly kept and reported to relevant departments for unified treatment.
2. Tools for holding, grinding and stirring highly toxic substances (narcotic drugs) must be fixed, and shall not be used for other purposes or thrown about. Packages after use must be stored and handled in a unified way.
3, with radioactive waste must be placed in a clearly marked container sealed preservation, reported to the relevant departments for unified treatment.
Six, expired solid drugs, high concentration waste reagents must be packaged in the original reagent bottle, should be regularly reported to the equipment asset management office for recycling, and shall not be buried or included in the collection bucket for processing.
Seven, the laboratory or the use of units must designate a person responsible for the collection, storage, supervision and inspection of hazardous and toxic waste management.
Eight, the laboratory or the use of units should be set up in accordance with the provisions of the collection barrel, at any time classified collection of harmful and toxic waste liquid, solid waste, fixed-point storage, so that someone is responsible for the safe custody. Waste liquid/
Danger warning signs and notices must be posted in the storage place of solid waste collection barrels.
Nine, the school asset management office is responsible for the supervision and inspection of schools and departments of toxic and hazardous waste treatment and management.
Ten, the school regularly notified by the competent administrative department of environmental protection, hazardous waste business license units to collect harmful and toxic waste. Each laboratory or user shall fill in the "Waste Record and Transfer Form" provided by the unit as required.
Eleven, in violation of the provisions, still dumping waste liquid, waste residue units and parties to give criticism and education, until the person in charge of the unit and the relevant responsibilities. If serious consequences are caused, penalties and fines shall be imposed.
Regulations on the management of laboratory wastes
Chapter I General Provisions
Article 1 In order to standardize and strengthen the management of laboratory wastes in our school, prevent laboratory wastes from polluting the environment, ensure the campus environment and public safety, and ensure the health of teachers and students in our school, these measures are formulated in accordance with the Law of People's Republic of China (PRC) on the Prevention and Control of Environmental Pollution by Solid Wastes and the Measures for the Prevention and Control of Environmental Pollution by Abandoned Hazardous Chemicals.
Article 2 Teachers, students and staff of the whole school must establish awareness of environmental protection, advocate experimental methods conducive to environmental protection, try to avoid or reduce the generation of laboratory waste, and fully recycle and rationally use reusable laboratory waste.
Article 3 Laboratories and related personnel who produce laboratory wastes in schools shall abide by these measures. Any unit or individual has the right to report violations of these measures.
Chapter II Classification of Laboratory Wastes
Article 4 Laboratory wastes include hazardous wastes and general wastes.
Laboratory hazardous waste refers to the waste generated by the laboratory under the following circumstances:
(1) Having one or more hazardous characteristics such as corrosiveness, toxicity, flammability, reactivity or infectivity;
(2) It is not excluded that it is dangerous and may have harmful effects on the environment or human health, and it needs to be managed according to hazardous waste.
General laboratory waste refers to other wastes generated in the laboratory except hazardous waste.
Article 5 Hazardous wastes in laboratories must be classified, collected, stored and disposed of in accordance with these Measures. General laboratory wastes should be stored in designated places and cleaned regularly according to the requirements of the health department.
Article 6 According to the nature and characteristics of hazardous waste in laboratories, it can be divided into the following categories:
(1) Chemical hazardous wastes: highly toxic chemicals and unknown substances, high-risk chemicals, general chemicals, general chemical waste liquid and solid wastes contaminated by chemicals;
(2) Biohazardous wastes: the carcasses, limbs and tissues of experimental animals contaminated by pests, chemicals and radioactivity; Dead bodies, limbs and tissues of experimental animals that are not contaminated by pests, chemicals, radioactive substances and radioactivity; Biological experimental equipment and consumables; Other biological waste liquid;
(3) Hazardous waste of ionizing radiation: radioactive sources, radioactive wastes and abandoned radioactive devices;
(4) Other hazardous wastes.
Chapter III Management Organization and Responsibilities
Article 7 The management of laboratory wastes shall be carried out under the three-level management system of schools, secondary units and laboratories.
Eighth laboratory technical safety office is the school-level management department of laboratory waste, and its main responsibilities are:
(a) to implement the relevant national guidelines, policies, laws and regulations, combined with the actual situation of our school, formulate and organize the implementation of laboratory waste management rules and regulations;
(two) responsible for the safety access of laboratory construction projects and experimental projects that produce hazardous waste in the laboratory;
(three) to organize the establishment of the collection, storage and treatment system of hazardous waste in the laboratory of the whole school;
(four) to supervise and inspect the collection, storage and treatment of hazardous waste in the laboratory of the whole school;
(five) to coordinate and deal with the problems in the process of hazardous waste management in the laboratory, and report the major problems to the laboratory technical safety working Committee for decision.
Article 9 Secondary units shall designate special persons to be responsible for the management of hazardous wastes in their own laboratories. The main responsibilities of the secondary units are:
(a) to implement the relevant provisions of the state and the school, organize the laboratory of this unit to formulate and implement the relevant responsibility system, the collection, storage and treatment procedures of hazardous waste in the laboratory, accident prevention measures, accident emergency plans and other management systems;
(two) to organize the laboratory of the unit to implement the collection and storage places and corresponding facilities for hazardous waste in the laboratory;
(three) to organize the laboratory of the unit to complete the collection, storage and disposal of hazardous waste in the laboratory according to the requirements of the specification;
(four) to supervise and inspect the collection, storage and disposal of hazardous waste in the laboratory of this unit, and organize rectification in time when problems are found.
Article 10 The laboratory shall designate a special person to be responsible for the management of hazardous wastes in the laboratory. The main duties of the laboratory are:
(a) to implement the relevant provisions of the state and the school, formulate and organize the implementation of the relevant laboratory responsibility system, laboratory hazardous waste collection, storage and treatment procedures, accident prevention measures, accident emergency plans and other management systems;
(two) the establishment of hazardous waste collection and storage sites and corresponding facilities in this laboratory;
(3) Complete the collection, storage and disposal of hazardous wastes in the laboratory according to the requirements of the specifications;
(4) Check the collection, storage and treatment of hazardous wastes in our laboratory, and make timely rectification when problems are found.
Chapter IV Collection and Storage of Laboratory Wastes
Article 11 Secondary units and laboratories shall not mix hazardous wastes (including experimental instruments polluted by hazardous wastes) with domestic garbage and other general wastes for storage; Do not mix, collect, store or dispose of chemical hazardous wastes, radioactive wastes and experimental animal carcasses; It is strictly forbidden to dump, pile up, discard or scatter laboratory wastes at will.
Twelfth laboratory hazardous waste must be classified collection and storage:
Chemical hazardous waste:
(1) Chemical waste liquid should be collected according to the nature and danger degree of chemicals and put in special waste liquid barrels. Hazardous wastes with different types or abnormal reactions shall not be mixed, and compatibility tests must be carried out when collecting chemical waste liquid; The waste bucket shall be labeled and recorded;
(two) solid waste and bottled waste and general chemicals are collected in special plastic bags first, and then stored in storage boxes, which must have corresponding labels and records;
(3) The management of highly toxic chemicals adopts the "five pairs" system, that is, the safety management system with double custody, double locking, double accounting, double collection and double use as the core; Highly toxic waste liquid and waste shall be clearly marked and collected and stored in strict accordance with the Management Regulations of Highly Toxic Chemicals in Laboratory of Chongqing University;
(4) General chemicals should be stored in original bottles, and the original labels should be maintained, and if necessary, they should be marked as waste chemicals;
(5) General chemical waste liquid is usually divided into general organic waste liquid and inorganic waste liquid. The source of waste liquid should be known in advance, collected and stored separately, and mixed use of waste liquid is prohibited without knowing the source and nature of waste liquid; Waste bins should be clearly marked.
Biological hazardous waste:
(1) The carcasses, limbs and tissues of experimental animals that have not been polluted by pests, chemicals and radioactivity shall be sealed with special plastic sealing bags, and then stored in special freezer or freezer, and corresponding records shall be made;
(2) The wastes produced by the carcasses, limbs and tissues of experimental animals contaminated by pests, chemicals and radioactivity should be disinfected first, then sealed with special plastic sealing bags, labeled with harmful biological wastes, frozen in special freezer or refrigerator, and recorded accordingly;
(3) Biological experimental equipment and consumables: plastic products should be collected in special high-pressure ultra-thin plastic containers and recycled after regular sterilization; Discarded sharp objects (needles, knives, metal and glass, etc.). ) to use special containers to collect, unified recycling;
(four) other biological waste liquid that can be disinfected and sterilized shall be treated as domestic garbage after being treated to ensure that it is harmless; Those that can't be disinfected and sterilized shall be collected in special plastic bags, labeled with harmful biological wastes, frozen and preserved in a special freezer or refrigerator, and recorded accordingly.
Hazardous wastes generated by ionizing radiation:
(1) radioactive waste sources, waste liquid and waste ray devices shall be classified, recorded and marked according to relevant national standards, including types and nuclide names.
(2) Waste radioactive sources: separately collected, sealed, shielded and isolated according to the relevant requirements of the State Environmental Protection Agency; There are obvious radiation warning signs in the storage place, which are fire-proof and theft-proof, and are kept by special personnel.
(3) Radioactive waste:
(1) The long-half-life radioactive waste and short-half-life radioactive waste determined by the environmental protection department above the control level shall be reviewed by the radiation protection team of the unit and submitted to the environmental protection department for treatment according to the requirements of the environmental protection department;
(2) Short-half-life radioactive waste that is determined by the environmental protection department to be below the control level can be treated as general waste;
(3) Liquid radioactive waste must be solidified by professionals hired by the environmental protection department before treatment.
(4) Abandoned radioactive devices: Before scrapping, they must be approved by the environmental protection department, and professionals are required to take out radioactive sources and dispose of them in the manner of radioactive waste.
Thirteenth before the hazardous waste is collected and treated by qualified units, secondary units and laboratories must properly keep the hazardous waste in the laboratory according to the following requirements:
(1) In principle, secondary units are required to centrally store and manage hazardous wastes in the laboratory, ensure the safety conditions of temporary storage facilities, keep ventilation, stay away from fire sources, avoid high temperature, sunlight and rain, and avoid incompatible hazardous wastes being stored at close range; For secondary units that do not have centralized storage conditions, the laboratory is responsible for temporarily storing laboratory hazardous wastes in appropriate positions in the laboratory, and may not store them in the laboratory corridors and public areas where students conduct experiments.
(2) Hazardous wastes that are flammable, explosive and produce toxic gases at normal temperature and pressure should be pretreated by the laboratory before storage to make them stable and recorded as required.
(3) There should be enough space in the container for containing liquid hazardous waste to ensure that the liquid in the container cannot exceed 75% of the container volume.
(4) Other articles shall not be placed in the special biological freezer or refrigerator to avoid cross infection.
Chapter V Disposal of Laboratory Wastes
Fourteenth secondary units and laboratories shall, according to their characteristics, output and environmental protection requirements, formulate and implement corresponding treatment measures to ensure that the concentration of harmful substances reaches or falls below the national safety emission standards before being discharged into the atmosphere.
Fifteenth laboratory hazardous waste must be disposed of by units with corresponding disposal qualifications.
Sixteenth units with hazardous waste disposal qualifications must take effective measures to prevent the spread, loss, leakage or cross-contamination of waste before recycling.
Seventeenth secondary units and laboratories in the transfer of hazardous waste in the laboratory, the relevant personnel must be present, and make a good record of the transfer, fill in the transfer of hazardous waste, and submit the records to the relevant units for the record;
Eighteenth laboratory hazardous waste treatment costs borne by the school and the two * * * units. For projects that produce hazardous waste in the laboratory, the secondary unit may charge a certain treatment fee.
Chapter VI Other Related Matters
Article 19 Sites, facilities, equipment, containers, packages and other articles polluted by laboratories in the process of collecting, storing and disposing of hazardous wastes must be treated to eliminate pollution before they can be used again.
Article 20 The inspection, rectification, accident treatment and accountability of the collection, storage and treatment of hazardous wastes in laboratories shall be carried out in accordance with the relevant provisions of the Measures for the Administration of Laboratory Technical Safety of Chongqing University.
Chapter VII Supplementary Provisions
Twenty-first matters not covered in these Measures shall be implemented in accordance with relevant national laws and regulations.
Twenty-second these measures shall come into force as of the date of promulgation, and the school shall authorize the laboratory technical safety office to be responsible for the interpretation.
How to deal with related articles after chemical experiments;
★ How to deal with the waste liquid after the chemical experiment?
★ What safety should I pay attention to when doing chemical experiments?
★ Matters needing attention in doing chemical experiments
★ Methods of doing basic experimental operations in chemical experiments
★ Matters needing attention in doing chemical experiments
★ Basic operation and matters needing attention in chemical experiment
★ Summary of matters needing attention in doing chemical experiments
★ A complete collection of matters needing attention in chemical experiments
★ Summary of matters needing attention in doing chemical experiments 2020