CS232094B1 - A method of thermally disposing of chlorine-containing waste plastics at the same time as obtaining thermal energy - Google Patents

Abstract

The essence of the invention lies in the fact that the waste plastic is cut or crushed into small parts, its surface is activated so that after thorough rinsing in water it is wetted over the entire surface, after which the waste plastic thus treated is wetted with an aqueous solution of glue, after thorough homogenization it is partially dried and mixed in a mixer with lime or limestone and optionally with waste tempering salts containing nitrites and nitrates and after thorough mixing with coal, the thus treated mixture is burned in solid fuel combustion systems.

Description

The invention relates to an environmentally and energy-efficient thermal disposal of pre-treated chlorine-containing synthetic waste materials.

Until now, waste plastics containing chlorine compounds of the PVC type, artificial leather and imitation leather, cable insulation and similar materials are disposed of by deposition, less frequently incinerated in different types of incineration plants such as grate fires for combustion, incineration boilers etc., where they are usually incinerated in a mixture with municipal waste.

The disadvantage of these methods of disposal of plastic waste is that in case of landfilling into open landfills in the nature it is necessary to pack / press / treat the landfills, protect them against misuse by third parties in a fenced area and load with soil, strictly control their impact on the environment / pollution of surface and ground water etc.). Taken together, these measures represent considerable demands both on the costs of transporting waste and maintaining landfills, as well as on the labor force needed to ensure these measures. In the case of disposal by incineration, this method has the disadvantage of releasing hydrogen chloride from the waste, which reacts at high temperatures with the metal parts of the combustion plant and intensively corrodes them. high temperature corrosion. In addition, the released flue gas passes into the atmosphere and degrades the environment.

Disadvantages of the prior art methods of disposal of waste plastics containing chlorine compounds are eliminated by the method of their thermal disposal after prior chemical treatment according to the invention, which consists in cutting the waste plastics into small parts, activating the plastic surface with potassium permanganate solution and acid sulfuric so that after thorough rinsing in water it is wetted all over the surface, after which the treated plastic waste is wetted with an aqueous adhesive solution, after

- the 2 232 094 homogenization is partially dried and mixed in the mixer with lime, optionally with waste nitrite and nitrate waste salts, after thorough mixing with coal; the mixture thus treated is combusted in solid fuel combustion systems.

The benefits of disposing of waste plastics containing chlorine compounds are both environmental recovery and energy benefits, as they have a higher calorific value and considerably less ash content than less valuable industrial coal burned in the grate hearths of industrial boilers, intense combustion of waste will improve combustion of this coal and increase efficiency of its use. There is a double energy effect: waste plastics are used for energy and less valuable coal is burned better with less losses , thereby achieving a further improvement of the energy balance in solid fuel combustion plant systems. In addition, the addition of lime or limestone to the waste plastic also binds the sulfur contained in the low-grade coal, thereby reducing the exhalation of the strongly corrosive sulfur dioxide.

Example 1

Waste pieces of PVC-coated cardboard are cut into small pieces by a saw mill. An aqueous solution of 4 g / ^{l of} potassium permanganate and 5 g / ^l of sulfuric acid (calculated as 100%) in steel inside the rubberized tub is prepared. The disintegrated waste is immersed in this solution for several minutes in a perforated basket, shaken several times in the basket to completely wet the waste. Then the waste basket emerges and the waste is rinsed thoroughly. The surface of the waste must be wetted over the entire surface. The rinsed wastes are poured into the mixer and water-soluble carboxymethylcellulose-dextrin / Koramex Spolana / glue is added while stirring to wet the surface of the waste. The preparation dissolves within about 12 hours. The filler used is ground limestone, which is added to the adhesive in a 1: 1 weight ratio, the mixture being thoroughly homogenized by stirring. The wetted waste material is poured onto a perforated sheet, a sieve with larger openings, to reduce the contact surface of the material with the bottom and thus reduce the possibility of sticking to the substrate. At the same time, excess adhesive solution flows into the backed container for further use. The mass spreads out in

- 3,232,094 a thin layer on the surface and allow to dry freely. The mass treated in this way is mixed in a mixer in a weight ratio of 1 and 1 with lime and the mixture is added in a weight ratio of 1s1 to charcoal.

Waste from PVC boards is pulverized. Its surface is activated as in the previous case. After rinsing in water, it is poured into the mixer, the glue solution is added with stirring so that the surface of the waste is slightly wetted. After complete mixing, lime and waste tempering salts containing nitrites and nitrates in a weight ratio of 1: 1: 1 are added. The mixture thus treated is burnt in a grate furnace with coal in a weight ratio of 1: 1. Example 3 = ·

PVC-based artificial leather wastes are disintegrated, their surface is activated as in Example 1, wetted with a suitable adhesive and mixed in a 1: 1 weight ratio with lime. The treated waste is burned in a rotary kiln.

Claims (1)

SUBJECT OF THE INVENTION Method of thermal disposal of waste plastics containing chlorine compounds with simultaneous gain of thermal energy, characterized in that the waste plastic is cut or crushed into small parts, its surface is activated by a permanganate activation solution 4 ml of potassium concentration of 2 gl to 10 gl and sulfuric acid at a concentration of 2 gl ^"1 to 10 gl" ¹ so that the whole surface wets and then pre-treated plastics material is wetted with a solution of adhesive and mix / weight ratio of 1: 10 to 10: 1 / with lime or limestone, or this mixture is mixed with a waste tempering salt containing nitrites and nitrates in a weight ratio of 1:10 to 10: 1 and after homogenization of the mixture it is burned with coal to which it is added. weight ratio 1:50 to 50: 1 ·