Design and development of the high-tech production of multi-purpose asphaltic concrete modifiers

Design and development of the high-tech production of multi-purpose asphaltic concrete modifiers
Technology description
The essence of innovation is to design and create a high-tech production of granular complex multi-purpose modifiers by pressing ("pelleting") the components with different chemical and physical properties to improve the shear resistance and the temperature fracture toughness, the fatigue crack resistance and the corrosion resistance of the asphaltic concrete.

There is the same product on the market, but the technology has higher quality basic specifications
There is an opportunity for practical implementation

Solved problems
These days modifiers are widely used in road construction (eg, Genicel, Lucobit, Duroflex, PR-Plast, Polybilt, NAF, Parawax et al.). They can be supplied directly into the mixer in the process of road concrete mix production, which enables the manufacturer to do without expensive stage of modified bitumen production. To date, three main types of road concrete mix additives are produced: additives based on cellulose fibers and bitumen (processing additives); multicomponent polymeric additives based on the secondary component (modifying additives); additives based on rubber-binder (modifying additives).
The main disadvantages of modifying additives for road concrete mix (as opposed to bitumen modifying additives) are the following:
- It is complex to homogenize the components in modifying additives (e.g., polymer, rubber) in the composition of road concrete mixes in the process of their production, which entails additional costs due to the increase of the mixing time;
- It is difficult to simultaneously improve some opposing properties of asphaltic concrete (eg shear resistance - temperature fracture toughness; shear resistance - fatigue crack; shear resistance - corrosion resistance, etc.) in a single-component modifier composition based on polymers and waxes;
- The additives lack technical and economic efficiency in ensuring the increase of the strength and the deformational stability (for example, cellulose, wax-based);
- asphalt mixes with additives based on polymeric components require more remoulding effort.
A common disadvantage of the preparation process of modified road concrete mixes based on polymer additives (including modified bitumen) is the higher temperature required for their preparation (170-180 °C – the temperature of road concrete mixes at the mixer outlet), which entails additional production costs and reduces the parameters of its environmental performance. In this respect, wax-based additives have their advantage. The temperature of modified asphaltic cements based on them at the mixer outlet is about 140-150 °C.
Also when one-component polymeric additives are used in the production of road concrete mixes with a high content of binder additionally fibrous (cellulose) additive are needed, which reduces the economic efficiency of the modification.
In connection with the above mentioned, we suggest that the development of scientific and practical bases for the production of complex multi-purpose asphalt mixes modifiers is of great interest. The manufacturing process of this kind of additives is complicated by the following features that must be taken into account in the course of the project implementation:
- it is necessary to combine components of different chemical nature (polymers, waxes, cellulose, etc.);
fiber bulk density is 40-60 kg / m3 while shredded polymer bulk density is 150-500 kg / m3).
- it is necessary to combine components with different melting points (e.g., wax softening point is 40-60 °C and polymers softening temperature is - 80-160 °C);
- it is necessary to combine components with different bulk densities (for example, cellulose fiber bulk density – 40-60 kg/m3 and crushed polymer bulk density – 150-500 kg/m3).

Stage of Development
Proven technology for small-scale production
Certificates of product conformity and safety: a mandatory product certification is not required. Act of the state sanitary-hygienic examination № 16-12-04 / 7679 of 04.01.2010. Test reports №№ 04-52 / 152-158П by the Research Institute of Fire Safety and Emergencies of the Republic of Belarus.
A number of technical normative legal acts have been developed:
- Technical specifications ТУ ВУ 690610504.710-2010 "Polymer multi-component modifying additives ";
- Technological regulations TP 100232486.006-2011 "Experimental technological regulations on the production process of multi-component modifying additives based on secondary polymer components";
- Technological regulations TP 100232486.007-2011 "Experimental and technological regulations for the production of road concrete mixes modified by multi-component additives based on secondary polymer components";
- Technological regulations TP 100232486.008-2011 "Experimental and technological regulations for the production of bitumen modified by multi-component additives based on secondary polymer components."

Currently, the network public highways of the CIS makes more than 1066,1 thousand kilometers. Construction and reconstruction of international roads and bridges is a priority for every state of the CIS. The transport and operational state of public roads does not meet adequately the needs of road transport. Almost all the CIS countries formed the program of construction and reconstruction of roads in the near and distant future, which indicates good prospects of investment in the establishment of industries related to road construction. Experts estimate that the market share of asphalt modifiers will be more than 100 million US Dollars per year.

Risks of the project and anti-risk activities
The implementation of the project is accompanied by various risks that could affect the final result. Among the main risks are the following:
Marketing risks. Major marketing risks are assessed as medium. Marketing risks are minimized due to the fact that the existing analogues in the market have significantly higher cost. In addition, it is planned to organize and conduct complex marketing activities that will enable rapid response to changing market conditions.
Technological risks. This type of risks also include problems with the maintenance of machinery and equipment, acquisition of quality raw materials, availability of skilled manpower for operation of the purchased equipment, as well as factors affecting the quality of the products and methods of its support. These risks are assessed as medium. State Enterprise "Scientific and Technology Park of BNTU "Polytechnic" has the necessary experience in the selection of high-quality technical equipment and highly qualified management personnel who have experience in the industry. To reduce the technological risks, selection of equipment will be performed by qualified personnel for the sake of the innovation project and its needs.
Financial risks. Financial risks can be expressed in the inability to achieve the planned targets in terms of sales, due to the influence of both macro-economic factors (high inflation and the decline in effective demand, etc..), as well as factors related to toughening of requirements of banks at crediting.
The risk of resource supply and sales. To date, this type of risk is assessed as high, given the absence of the arrangements for the delivery of raw materials and well-established sales channels. The reduction of this risk is also planned as part of the marketing complex.
The risk of market oversupply and falling price for the product. The risk arises from the possibility that the company will not work on the planned production volume. The risk is assessed as low, as the demand for goods (work, services) of the enterprise, owing to specificity of its activity, is steady and stable.
Inflation risk. This risk is assessed as high, and belongs to the group of so-called systemic risks as the company cannot render immediate influence on it in order to minimize its negative effect.
Organizational risk. This risk is associated with the work in strict accordance with the schedule, as well as the timely commissioning of the equipment at the new site. Given the experience of the State Enterprise "Science and Technology Park of BNTU "Polytechnic" in the field of new productions, this risk can be assessed as low.