Vertical Conveying of High-Viscous Solutions
Development and Demonstration of Technology and Plant Prototype for Vertical Conveying of High-Viscous Mortars on an Air Cushion
Tech Area / Field
- PHY-NGD/Fluid Mechanics and Gas Dynamics/Physics
- OTH-BIT/Building Industry Technology/Other
3 Approved without Funding
Belorussian State Polytechnic Academy, Belarus, Minsk
- Akita University, Japan, Akita
Project summaryProject objective: to develop technology of vertical conveying of high-viscous mortars on an air cushion and on the basis of this technology to design and manufacture a pilot plant. The achievement of the Project objective will lead to higher efficiency of technological process of vertical conveying of mortars and make it possible significantly to reduce power consumption as size and weight of the plant are to be decreased as well.
Problem statement: conveying of high-viscous mortars to a great height by pipelines is of great importance to industry. However, this process is accompanied with considerable power consumption, because while flowing viscous mortar offers great resistance. In this connection, resistance reduction of flowing high-viscous mortars is of particular practical interest. A lot of scientists of different countries have studied the problems of resistance reduction while conveying high-viscous mortars. ( Cormick Mc. M., Bhattacharyva R. - Drag reduction engineer of a submersible null by electrolysis // Naval Eng. J., 1973, v.85, 2, p.11-16.; Phan-Thien N. -On a pulsating flow of slightly non-Newtonian liquids // J. Mech. Theor. et Appl. - 1982. - v. 1, № 1. - p. 81 - 89.; Bohme G., Friedrich R. - Peristaltic flow of viscoelastic liquids. - J. Fluid Mech., 1983, 128, March,109 - 122.). However, the method for resistance reduction which may be applied in industry has not been developed yet.
According to the proposed Project resistance reduction while conveying high-viscous mortars to a height is to be achieved with the help of an air cushion.
The idea of water resistance reduction with the help of air is not a new one and it was suggested by Frud. However, it is not possible to realize this idea for Newtonian fluids (water, mineral oils, glycerine etc.) and isolate flow from solid wall due to instability of boundary of phase separation. Theoretical developments of the Project participants have demonstrated that it is possible to achieve resistance reduction on an air cushion for non-linear and viscous-plastic (non-Newtonian) fluids (mortars, food and pharmaceutical pulps etc.). Preliminary laboratory experiments of the resistance reduction method on an air cushion are a cause for statement that the Project technology will finally permit to increase significantly efficiency of the plant, reduce power consumption for technological conveying process by 6-8-fold, at the same time weight and size of the plant are to be reduced.
Impact of the proposed Project on the progress in the field of development. Technology of conveying mortars on an air cushion is fundamentally a new one. Due to this the proposed Project will have a specific impact on the progress in industry, civil engineering and scientific research. This technology will allow to apply new methods for the organization of civil-engineering production. An
application of small-size plants with a special device for resistance reduction of mortars which are
to be conveyed to 80-100 meter height will be of great importance as they are characterized by rather simple design, cheapness in manufacturing process and requirements in them practically at every construction site. Such plants are unique because they do not exist in world practice, however there is immense demand for them.
While carrying stiff mortars to some height an application of the proposed conveying technology with a special resistance reduction device should give the following advantages over the current technologies:
· 6-8-fold decrease in power consumption at the same height of mortar conveying;
· 2-3-fold increase in delivery height at the same power consumption;
· conveying of mortar with lower flowability;
· increase in capacity due to higher conveying speed;
· decrease in wear of conveying pipeline set;
· preservation of the required characteristics of conveyed mortar;
· provision of continuous conveying process;
The original design of the plant and method of resistance reduction on an air cushion when working
medium does not touch a pipe wall provide high increase in efficiency and significant decrease in power consumption. Small overall dimensions of the plant, using method of resistance reduction and low pressure of a mortar to be conveyed, will make it possible to apply it under the conditions when
application of an ordinary plant is considered to be inefficient.
Project Participants have a great experience in the development of resistance reduction technologies. They have taken part in some developments pertaining to defence industry where rheodynamic systems and processes of resistance reduction were used. So for nearly 25 years Mr.Zverhovski Y.E., Project manager, has been dealing with the developments of such technologies when underwater bodies and flying objects are moving. He is an author of a great number of papers on rheodynamics published in scientific journals and he has been granted a number of inventor’s certificates and patents for methods and devices applied in engineering industry and
Civil engineering. Other participants of this Project are highly-qualified specialists in the field of theoretical and applied research, engineering developments, mechanical and technological works in the defence industry. The Project team also includes specialists with broad practical experience in the field of development and introduction of civil-engineering technologies. There is some theoretical backlog in the fields mentioned-above and some technological developments to be applied with peaceful purpose.
Expected results of research. In the process of the Project execution the Project team intends to obtain the following results:
Task 1. Modelling and development of high-viscous non-linear and viscous-plastic mortar
flow on an air cushion.
· to obtain approximate evaluation of the conditions required for the formation of filmy air cushion between pipe wall and flowing non-linear and viscous-plastic fluid with the help of process simulation;
· to carry out preliminary experimental evaluation of the parameters of technological conveying conditions required for a pilot-plant with the help of a device model;
· to develop the process of air cushion formation and conditions in accordance with rheological factor of a mortar;
· to investigate and analyse influence of air cushion thickness and geometrical parameters of the device on the process of resistance reduction;
· to determine optimum parameters of the process.
Task 2. Development, manufacturing and adjustment of power-efficient pilot plant to be applied for conveying mortars on an air interlayer.
· to develop optimum project and design solutions in respect of the proposed plant;
· to select materials required for manufacturing the proposed plant;
· to elaborate manufacturing process for the proposed plant;
· to manufacture operating pilot plant and test it in accordance with international standards.
The results of the scientific development may be used for arrangement of full-scale production of the proposed plant with due account of the conditions where the plant is to be applied. Such action will be directed to meet the requirements of various branches of civil engineering. In the future the proposed technology may find its application in manufacturing plants for conveying various viscous-plastic fluids (food and pharmaceutical pulps, oil, clay suspensions, etc.) to some height. It will be possible to start production of this plant with commercial purpose as well. Scientific-research laboratory using present facilities will be able to manufacture 10 – 15 plants per year. It is supposed that a State certificate is to be awarded to the proposed plant . In order to start properly production of this plant with commercial purpose and promote the development results on the international market it is necessary to have foreign collaborators (marketing research, consultative services in protection of intellectual property etc.)
While executing the Project the samples of all the units of the plant are to be manufactured. The experimental works with the purpose to inspect the operation of the plant itself and its separate components are to be carried out as well. After completion of the development of the required operational conditions the operation of the proposed plant is to be demonstrated under actual conditions.
Conformity of Project activities with ISTC goals. The proposed Project fully conforms to the goals and mission of ISTC:
- while executing the ISTC Project pertaining to manufacturing equipment for civil engineering the participants of the proposed Project ,previously working in defence industry, will get the opportunity to re-orientate their knowledge and skills towards peaceful activity;
- research work and manufacturing of the plant which is to be used for vertical conveying of high-viscous mortars to great height will exert a positive effect on applied research and development of technologies with peaceful purpose in the field of ecology, conservation of energy and decrease in power consumption;
- the proposed Project will significantly facilitate to solve a number of national and international problems in the field of civil and industrial engineering and in other industrial technologies concerning conveying of food and pharmaceutical pulps, high-viscous oil production;
- the proposed Project will create the conditions required for the integration of the Project participants into international scientific community and favour transit to market economy.
Data about the scope of activities: Total scope of the Project activities constitutes 146 man/months with 24-month duration. Participation portion of weapon scientists and experts will constitute 85 man/months or 58.2% of total scope of activities. While developing design of the plant to be used for resistance reduction on an air cushion it is advisable to resolve the following tasks:
Task 1: Modelling and development of high-viscous non-linear and viscous-plastic mortar flow on an air cushion.
This Task is to be solved within 58 man/months.
Task 2: Development, manufacturing and adjustment of power-efficient pilot plant to be applied for conveying mortars on an air interlayer.
This Task is to be solved within 88 man/months.
Role of foreign collaborators:
Actual role of foreign collaborators is the following:
- mutual participation in discussions of the Project results at seminars and symposiums, mutual publication of experimental data;
- participation in testing of operation of separate units and pilot plant, attestation of output parameters of the developed plant;
- assistance in starting commercial production, promotion of the development results on the international market (marketing research and its organisational support);
- consultative services in protection of intellectual property, mutual patenting.
Technical approach and methodology are determined by the necessity to increase efficiency of the plant to be applied for conveying high viscous mortars, decrease of power consumption and ensure conveying of stiff mortars to greater height. Improvement of these characteristics of the plant may be achieved as a result of ‘quasi-bar’ flow of rheologically-complicated high-viscous plastic mortars with large structural characteristic when ‘quasi-solid’ core of the flow fills the whole cross-section of the pipeline (flow of concrete in concrete-conveying pipeline). Studying especially such cases the BSPA scientific-research team has been the first one in the world to develop the unique power-saving method for resistance reduction while conveying high viscous non-linear and viscous-plastic mortars in vertical pipelines. It has become possible due to formation of filmy gas interlayer as a solid cylinder between a pipe wall and laminar flowing fluid. Peculiar features concerning manufacturing of the plant to be applied for mortar conveying are attributed to the development of a special device for resistance reduction which has unique characteristics. Solution of the problems concerning its design is closely connected with difficulties of theoretical forecast while making calculations.
The Project team’s conviction for normal operation of such plant is based on a number of positive theoretical developments and laboratory experiments on resistance reduction while using an air interlayer, which is to be considered as the Project “know-how”. The Project manager has a number of inventor’s certificates and patent in this field.
It is necessary to follow requirements to the parameters of a mortar pump, selection of structural material, calculations of optimum operational pressure in a conveyed mortar and an air interlayer. Manufacturing of some units is rather labour-consuming process which requires high accuracy.
The cost of the plant for conveying stiff mortars depends on the requirements of concrete operational conditions. In the process of the execution of the Project it is presumed to develop the plant for conveying mortars to the height of 80-100 meters, with capacity approximately 4m3 /h (typical capacity for actually frequently-found scope of concrete works), as there is an excessive demand for the plants with similar characteristics.
The International Science and Technology Center (ISTC) is an intergovernmental organization connecting scientists from Kazakhstan, Armenia, Tajikistan, Kyrgyzstan, and Georgia with their peers and research organizations in the EU, Japan, Republic of Korea, Norway and the United States.
ISTC facilitates international science projects and assists the global scientific and business community to source and engage with CIS and Georgian institutes that develop or possess an excellence of scientific know-how.