The process of calcining petroleum green coke refers to a separate technological process of oil refining and is separated into a separate installation of Petroleum Coke Calcining Unit (PCCU).
The raw material of the PCCU is "green" raw coke. The product of the PCCU is calcined coke. Products are in demand in the aluminum industry for the manufacture of anodes for electrolyzers, in the electrode industry for the manufacture of electrodes for electro-metallurgical furnaces, including large diameter electrodes. Additionally, high-quality petroleum cokes are used in the ferrous metallurgy industry to control the carbon content in the electric arc melting of high-quality steels.
The Basic Technological Diagram of the PCCU
In 2012-2013, employees of "Green Ray Ltd.", as part of a team of authors, took an active part in the development of a new solution (Utility Model Patent No.120419 of 2012, Patent for Invention No.2492211 of 2013), which considers the possibility of pre-DRYING and STABILIZING the granulometric composition of petroleum coke DCU before its calcination in PCCU with simultaneous separation of coke fractions in a suspended layer using a separate device for this purpose - Aerial-fountain Drying. Copies of the Patent can be found on the website page at the link:
The Basic Technological Diagram of the PCCU with the inclusion of the Aerofontane Drying
The goals of a Patent-protected Technical Solution are the ability to :
- stabilize the qualitative and granulometric composition of the PCCU raw materials;
- stabilize the operation of the calcining furnace and the technological process of calcining;
- reduce the thermal load on the drum calcining furnace by reducing the free moisture content in the raw materials of the PCCU;
- increase the productivity of the PCCU at the output of the product;
- obtain new carbon-containing DCU products based on the results of separation and drying of the raw;
- reduce the energy consumption per unit of product PCCU;
- increase the energy efficiency of the PCCU operation by more complete utilization of the residual heat of the PCCU exhaust gases;
- reduce the dust and ash load on the heat recovery boiler, reduce the rate of contamination of its heat exchange surfaces, and increase the steam output of the boiler;
- reduce emissions on the environment in the form of harmful substances, including ash, unburned coke dust, and CO2;
- improve the quality of the PCCU product - calcined petroleum coke;
- reduce the loss of valuable grades of petroleum coke (Needle Coke http://greenrays.ru/en/needle-coke.html).
Effective calcination of petroleum coke, especially its expensive varieties, such as Needle Coke, is very relevant, since it is a question of harmonious and efficient operation of the oil refining, carbon-graphite, electrode, aluminum, ferrous and non-ferrous metallurgy industries.
On March 11-12, 2020, the VI International Forum "NEFTEKOKS-2020" was held in Moscow, where the employees of "Green Ray Ltd." together with the Ufa State Petroleum Technical University (USPTU) presented a Report on the topic:
"Systems for preparing DCU petroleum coke for calcination at PCCU in order to improve the quality of the final product, increase productivity and reduce operating costs and losses".
The above-mentioned invention (Patent No. 2492211) is supplemented, the technical solution is improved by the inclusion of new provisions and ideas.
The Report presents the classification of the products of DCU and PCCU by destination and consumers:
The Report groups the main products of DCU and CCU in accordance with the requirements of the Technical Specifications of the consumers of the product:
In addition, attention is focused on the feasibility of building and operating DCU together and in combination with PCCU at their location on the production site of the Refinery in connection with the following arguments:
- reduction of logistics costs for long-distance transportation of petroleum coke to consumers, associated with a reduction the water content in the coke from 10% to 3%;
- reduction of consumer costs for downtime and damage to railway rolling stock associated with freezing of bulk coke with a high water content in winter;
- correct unloading of coke from hoppers and gondolas at the destination of the consumer in winter;
- increase of energy efficiency and optimization of the energy balance of the joint work of DCU and PCCU due to the optimal utilization of the heat of the flue gases from both Units at the Refinery site.
Technological Diagram of joint work of DCU and PCCU with the inclusion of Aerofontane Drying and the production of new coking products:
The actual version of the Report can be sent to you upon request.
The experience of "Green Ray Ltd" employees in works related to Petroleum Coke Calcination Units (PCCU) is presented in Tables 1 and 3 in the section "Qualifications and experience" on the "Company" page of this web-site: