Environment and ecology of any industry have gained a certain place in our reality; the requirements for adhering to regulations are getting more and more stringent. This issue is closely related to coke and coke production.[1]
A scientific novelty is in that will be appraised economic and ecological effect from introduction of the offered technology. It is assumed to define optimum correlation of traditional technology of coking and technology without catching of chemical products of coking, oriented on domestic factories. As a practical value of results of researches introduction ecologically of meaningful measures is planned on the enterprises of Ukraine.
Goals and objectives of the work
Goal: perform a study into technological ways of reducing emission of gaseous toxic matter in the processes of coke production.
In order to reach this goal it is planned to achieve the following objectives:
- Analyse national and foreign works on the ecological aspect of coke production;
- Establish the main features of the chemical products of the coking process that are caught from the coke gas;
- Consider different ways of utilising the chemical products of the coking process and technological ways of improving the ecology of the traditional coking technologies;
- Assess the feasibility of implementing the technology without catching the chemical products of the coking process;
- Estimate the economic and ecological effect of implementing the technology without catching the chemical products of the coking process;
- Find the optimal ratio between the traditional coking technology and the technology without catching the chemical products of the coking process.
Analysis of the situation at national and foreign coke production
Coke production has the leading position in dangerous, particularly carcinogenic emissions that are most dangerous for the people’s health among other industries.
Coke production is a combination of specific productions related to high-temperature processing of (furnace) charge without access of air and further processing of the emitted coke gas in order to a whole range of valuable chemical products. Traditional technological processes very often are associated with emission of dangerous substances contained in the coke gas, such as ammonia, carbon oxide, nitrogen oxide, sulphur dioxide, hydrogen sulphide, cyanic nitrogen, benzol, naphthalene, phenols as well as coal and coke dust, into the atmosphere. The main sources of emissions: operations on loading/unloading furnaces, excess gases, aspiration gases from the coal preparation and coke sorting systems, coke battery pipes, and also scattered emissions from the doors, posts, feeding hatches etc.[2]
Technological ways of reducing of reducing emission of gaseous toxic substances in the traditional coking technology
In order to reduce dust in the coal preparation workshop all the equipment shall be provided with special aspiration systems purifying the air through wet and dry filters before it is emitted into the atmosphere.
Smokeless feeding helps to reduce dangerous emissions from the coke furnaces. This method can reduce dangerous emissions 10-15 times.
For coke drawing it is possible to use a special system for dustless coke drawing with further purification of trapped gases from coke dust in dry dust catchers.
Coke can be put out in two ways – wet or dry. Technical or running water can be used for wet putting out. This process is accompanied by plentiful emission of dangerous substances into the atmosphere. In order to reduce dangerous releases during coke putting out it is possible to use the dry method by using rare gas. The system for dry coke putting out is equipped with an aspiration tool for purifying the air from dust before releasing it into the atmosphere.[3]
Analysis of the technology without catching the chemical products of the coking process
The bulk of coke is got in ordinary stoves. The multicamerate system is there realized with catching of coke gas and chemical products. Less than 15% general production of coke volume get on technology without catching of chemical products of coking. Such stoves presently operate in the USA, Australia, China and India.[4]
Most essential features, distinguishing coking technology without catching the chemical products:
- coking is in a flat layer;
- work of stove at low pressure;
- serve of air directly in the stoves;
- complete incineration of raw coke gas is in every separate stove;
- absence of by-products and sewages.
Ecologically favourable work of coke stoves without catching of chemical products of coking is predefined implementation of next terms:
- prevention of the contaminating emission at the method of “top load”;
- application of methods of limitation of the emission at loading of coke;
- application of the newest systems of cooling at extinguishing of coke;
- multi-stage incineration of raw coke gas in heatings channels with the purpose of diminishing of the emission NOx;
- utilization of heat of outgoing gas;
- desulfurizing of outgoing gas.[5]
Conclusions
In the nearest prospect 2015 to production steel in Ukraine can attain 48-50 million tons. Three of leaders of world ferrous metallurgy (China, Japan, USA) makes 7,6 million tons of steel – 52,7% from its general production (there are 1346,3 million tons in 2007). The deficit of coke is therefore forecast. Therefore consider especially important to mark following:
1. Appearing in the nearest 8-10 years of possibility on substantial reduction of consumption of production of coke and by replacement of it by a dust-coal fuel (partly by an anthracite, coke, natural gas), it is expedient to use for tearing down of old, building of new coke batteries, modernizations of technology of production of coke with the purpose of improvement of his quality and practically complete liquidation of the gaseous emission at all stages of coke production.
2. Approximately 5/6 part of production of coke volume needs to be translated on new technology of coking without taking and ordinary processing of coke gas which is carried out at a great ecological damage an environment.[6]
References
- Ковалев Е.А. Коксохимические предприятия Украины и проблемы экологии // Деловой вестник. - 2008. - № 3 [Электронный ресурс] / http://www.ucci.org.ua/synopsis/dv/2008/dv0803161.ru.html
- Дорман Е.И., Дудинский А.И. Новые энергосберегающие технологии в коксохимическом производстве // Промышленная энергетика. - 2005 - № 6 – С. 2-7.
- Старовойт А.Г. Перспективы получения кокса высокого качества в условиях современной сырьевой базы // Черная металлургия. – 2008 – № 3 – С. 17-21.
- Антонов А.В. Производство кокса без улавливания химических продуктов коксования // Новости черной металлургии за рубежом. – 2006 – № 1 – С. 11-15.
- Ухмылова Г.С. Сопоставление процесса коксования без улавливания химических продуктов и конкурентных технологий по экологическим параметрам // Новости черной металлургии за рубежом. – 2003 – № 2 – С. 25-28.
- Беркутов Н.А. Об улучшении экологической обстановки и условий труда персонала при обработке коксовых печей // Кокс и химия. - 2005. - № 7. – С. 25-29.
Important note
At writing of this abstract of thesis master's degree work is not yet completed. Final completion: December, 2009 Complete text of work and materials and materials on the topic can be got for on author or his leader after the indicated date.
© DonNTU 2009 Vislobod A.
