Formaldehyde pollution

Formaldehyde (the chemical formula is HCHO) is a colorless and easily soluble liquid with strong volatility and pungent odor. Indoor formaldehyde mainly comes from building materials, furniture, man-made panels, various adhesive coatings and synthetic textiles. The amount of formaldehyde emitted from fossil fuel combustion is very small, but smoking is an important source of formaldehyde.

Sources of formaldehyde pollution: (1) From plywood, blockboard, medium-density fiberboard, particle board and composite flooring used for interior decoration. Because formaldehyde has strong adhesion, it also has the functions of strengthening the hardness of the board and preventing insects and corrosion. Therefore, the adhesive used in the production of artificial boards is urea-formaldehyde resin with formaldehyde as the main component. Formaldehyde will gradually be released to the surrounding environment, resulting in excessive formaldehyde content in indoor air. At present, the country has formulated strict control standards. However, due to the unreasonable construction design, the use of more materials per unit area, and the fact that there are still materials that do not meet the national standards on the market, the indoor environment of formaldehyde caused by this reason Pollution accounts for more than 50% of pollution. (2) From furniture made of wood-based panels. As the home decoration in Chinese cities has become more rational, people have changed the concept of blind decoration a few years ago. The concept of light decoration and heavy decoration has been accepted by everyone. People choose better furniture after simple decoration. In this way, individual furniture manufacturers use unqualified plates and irregular manufacturing processes in pursuit of profit, making furniture a formaldehyde emission station. At present, this problem accounts for 30% of indoor environmental pollution. (3) From various other decorative materials containing formaldehyde, such as white latex, foam, paint and coatings. Latex adhesives are widely used in wood engineering and wall treatment in decoration and decoration, especially the formaldehyde in the latex enclosed in the wall is difficult to remove. (4) From interior decoration textiles, including bedding, wall coverings, wallpaper, chemical fiber carpets, curtains and fabric furniture. In textile production, in order to increase the anti-wrinkle performance, waterproof performance, and fire resistance, some formaldehyde additives are often added, which will release formaldehyde during use.

Formaldehyde pollution hazards: Formaldehyde has a strong irritating effect on the mucous membranes of the eyes, nose, and throat. The most common symptoms are eye irritation and headaches. In severe cases, it can cause allergic dermatitis and asthma. Since formaldehyde can react with proteins to generate nitromethine compounds to coagulate and denature the proteins in cells, it can inhibit cell function. In addition, formaldehyde can react with ionic chlorides in the air to form dichloromethyl ether, which is a carcinogen. Formaldehyde can be absorbed and enriched by indoor high specific surface materials, and will be released again when the indoor temperature rises, aggravating the pollution effect.

Formaldehyde pollution detection method: 1. The perfprator test value. 2. The amount of formaldehyde extracted from 100g wood-based panels measured by perforation extraction method (unit: mg/100g), reminder: Internationally recommended classification: E1 <9mg/100g 9mg/100g <E2 <30mg/100g. 3. The desiccators test value, the amount of formaldehyde (unit: mg/L) released by the test piece in the absorption liquid (distilled water) measured by the desiccator method. 4. The chamber test value measured by the climate chamber method is the amount of formaldehyde (unit: mg/m3) when the test piece is released into the air in a steady state as measured by the standard climate chamber.

Solution to formaldehyde pollution: 1. Activated carbon is a relatively cheap and practical method to remove formaldehyde. It is characterized by physical adsorption and thorough adsorption, which is not easy to cause secondary pollution. The physical function of activated carbon deodorizes and detoxifies; it has no chemical additives and has no effect on the human body, but it is easy to saturate and fail and needs to be replaced or reactivated frequently. 2. Through indoor air circulation, the content of harmful substances in indoor air can be reduced, thereby reducing the harm of such substances to the human body. In winter, people often close doors and windows tightly, and indoor and outdoor air cannot circulate. Not only will the content of formaldehyde in the indoor air increase, but also radon will continue to accumulate, even reaching high concentrations. 3. Plant decontamination can be selected for medium and low pollution: In general, indoor environmental pollution is light and moderate pollution, and the pollution value is below 3 times the national standard. Plant purification can achieve better results. Choose and place plants according to the different functions of the room and the size of the area. In general, for a room of about 10 square meters, two pots of 1.5 meters high plants are more appropriate. (Recommended indoor pollution control method: ventilation + activated carbon + formaldehyde removal plants, suitable for medium and low pollution) Choose and place plants according to the different functions of the room and the size of the area. Under normal circumstances, a room of about 10 square meters, 1.5 meters high plants in two pots is more appropriate.