The role of the industrial ecology is very high in the present society. It has to work up and to improve the technical security facilities of the environment and to develop the basics of the closed, wasteless or low-wasted technical loops and production on the basis of the harmful estimate.

          In this connection in 1999 “the program of reconstruction and technical reequipment of Avdeevskiy coke-processing works up to 2010” and scientific and technical program “enhancement of the environment” for the period up to 2015 were worked out at OJSC “Avdeevskiy coke-processing works”. In these documents the reconstruction and the further development of the production is closely connected with the actions aimed at the improvement of the environment situation.

          On of the first workshops which had to be reconstructed was the desulfurization shop № 1. This workshop is to refine the coke oven gas from the hydrogen sulphide up to the fixed by the technical conditions rate and to produce from the hydrosulphuric gas the sulphuric acid by wet catalysis. In this very shop the most important project of the above mentioned programs was run in 2001 – the coke oven gas refinement from the hydrogen sulphide up to 0.5 g/m³ with the production of the sulphuric acid according to the “Haldor Topse” technology. The realization of this project can guarantee the coke oven gas refinement up to the fixed by the international convention rate and in this way the emission of sulfur dioxide and sulphuric acid fog in the atmosphere will be reduced. Besides this, the above mentioned technology will increase the advanced sulphuric acid production and as a result it appeared the necessity of the replacement of the old heat exchangers for the sulphuric acid cooling.

         At present in chemical industry the plate-type heat exchangers are used for the liquid-to-liquid medium under the pressure up to 1 MPa and at the temperature up to 200 C which have some advantages as compared with the shell-and-tube heat exchanger for the same conditions.

         The first and one of the most important advantages is the compactness of the plate-type heat exchanger. The least occupies 6-8 times less place than the shell-and-tube heat exchanger with the same capacity. The compactness of the plate-type heat exchangers defines the lowest heat loss to the atmosphere from its surface without any additional lagging.

         The next advantage of the plate-type heat exchangers over the shell-and-tube heat exchangers is the fact that the first one need 80% less heat carrier than the second one. This decreases the amount of the manufacturing water used in the exchanger. This is possible because the heat carrier passing speed in the plate-type heat exchangers is about 2 times lower than in the shell-and-tube heat exchangers, the internal volume of the plate-type heat exchanger is 6 times less and the heat transfer constant is 1.5-3 times higher. Besides this, the heat carrier goes along the exchanger only once and its way is rather short.

         The design of the plate-type heat exchangers makes impossible the appearance of the leakings inside the device, which leads to the medium mixing: any leaking (except the physical destruction of the inside part of the plate) is fixed by sight. This fact decreases the heat carrier leakages, which are always exist in the shell-and-tube heat exchangers, and the cooling or heating carrier (water) can be used for technological needs of the factory.

         The comparison technical characteristics of the equal capacity plate-type and the shell-and-tube heat exchangers are stipulated in table1.

         Table 1 - The technical characteristics of the heat-exchange devices

         In the course of the comparative analysis and calculations, we came to a conclusion that the most appropriate device for the sulphuric acid cooling is the plate-type heat exchanger Alpha-Laval. This is the pack of the compressed on the paddings corrugated plates, the acid runs on the one side of it, the cooling reused water runs on the other side.

         The characteristic of the refrigerator is given below:

• the heat transfer surface — 64,48 м²
• the acid consumption — до 80 м³/h
• the cooling water consumption — до 205 м³/h
• the maximum allowed acid and cooling water pressure — 0,49 МPа
• the refrigerator resistance by the given consumptions
• by the acid — 0,12 МPа
• by the water — 0,055 МPа
• the temperature of the acid before and after the refrigerator— 67⁰С — 40⁰С
• the temperature of the cooling water before and after the refrigerator— 28⁰С — 42⁰C

         Hence, the setting of the Alpha-Laval plate-type refrigerator with design for the sulphuric acid cooling corresponds not only to technical, but to ecological demands as well.