MPC in water
The maximum permissible concentration (MPC) of harmfulelements are the established state acts of the norm of sanitary and hygienic rules. Failure to comply with the limit values indicated therein is an offense for which offenders are liable in accordance with the law. The MPC norm in water gives indications of those limit values of pollutants, the content of which does not entail damage to human health or life.
The main sources of toxic elementsthere are numerous functioning enterprises of the industrial complex. Their emissions are highly polluting air, soil and water. Chemical elements that have a negative impact on our environment, it is common to divide into groups, depending on the degree of their danger to humans. They include substances that have a danger:
There is also a group of dangerous elements.
MPC in water of various chemicals are reflectedin specially designed tables. There are also various formulas, the use of which makes it possible to calculate the limiting tolerance of toxins. They are used by specialists to carry out control measures for the water used by man. Such actions can be carried out by any of us. To do this, it is enough to analyze the state of drinking water in your house and compare it with the permissible norms of finding various elements in it. For example, the content in milligrams per liter should not be higher:
- dry residue - 1000;
- sulfates - 500;
- Chlorides - 350;
- copper - 1;
- zinc - 5;
- iron - 0.3;
- manganese - 0.1;
- Residual polyphosphates - 3.5.
The total hardness of water should not exceed seven milligrams per liter.
Great importance is also the control over the statesoil. It is the earth that serves as the accumulator and filter for various compounds. The MPC of sewage that is constantly discharged into the soil must also comply with the regulations, since the constant migration in its upper layers of harmful substances pollutes the entire environment.
According to sanitary-hygienic norms, in soil there can be no more:
- 0,02 mg / kg of benzapyrene;
- 3 mg / kg of copper;
- 130 mg / kg of nitrates;
0.3 mg / kg of toluene;
- 23 mg / kg of zinc.
If the MPC is exceeded in water, the authorities involved incontrol of the state of the environment, will determine the cause of this phenomenon. Quite often, the usual household waste affects the increase in the amount of chemicals in nature. At present, the problem of purifying water bodies from phosphate and nitrogen compounds is especially acute. In order to solve this problem, you can use three different approaches:
- the totality of the first two methods.
Adjustment to the normative value of MPC in water withusing chemical cleaning involves the formation of metal phosphates, which, being insoluble, settle at the bottom of a special container. This process occurs with the help of reagents. The use of the chemical cleaning method is widely used in industrial enterprises. Carrying out of these works is possible only by specially trained employees.
If phosphorus orP-bacteria, then this method is biological. This is a modern, natural approach to avoiding exceeding the MPC. Special zones of treatment tanks are supplied alternately with aerobic and anaerobic bacteria. This method is used in biofilters, septic tanks and aerotanks.
The combination of biological and chemical methods is used in purification systems, where it becomes necessary to accelerate and intensify the reactions of decomposition of impurities.