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Roofing & Waterproofing Essentials: The Industrial Use


Roofing, waterproofing and sealing materials, especially roll, sheet and custom-made products, are designed to ensure complete isolation of the structures of buildings and structures from the damaging impact of aggressive environment, especially water, humidity and atmospheric factors. In this regard, the materials of this group should be firstly watertight, and secondly, to meet strength, deformability, chemical resistance, water-resistant and durable.

The spheres of using of these materials are diverse. They are required for internal and external protection of underground buildings, pits, foundations, culverts and pipes, sewers, tunnels, vaults, trenches and other types of facilities from the effects of groundwater with dissolved therein aggressive salts, acids and alkalis, as well as other chemicals. Protective coatings are also used for the following purposes:

  • the isolation of reservoirs, ponds, reservoirs (protection bridge structures carriageway supports);
  • at the device impervious screens and fortification coatings in hydraulic engineering;
  • to isolate the bottom and slopes of channels in the construction of irrigation systems;
  • for filling cavities in rocks at the device bases and foundations;
  • in the protection of floors in production areas and bathrooms;
  • when applying water-filled flat roofs, roofing of buildings and sealing layers in the roof;
  • for sealing joints, expansion joints, holes in the panel construction and piping.

Waterproofing not only protects the surface from contact with an aqueous medium, but favors the steam and gas isolation and increase resistance to corrosion of structural material.

An excursion into history

The application of waterproofing materials began in ancient times. According to the excavations found that 4500-5000 years ago natural bitumen and tar was used as binders and waterproofing materials in the construction of the Egyptian and Babylonian structures, isolation channels and drains, foundations of palaces and temples. Walls and floors in barns and granaries protected bituminous paint that provides long-term preservation of grain and other agricultural products. To increase the strength and thermal stability of bitumen frequently added to the particulate materials (mineral powder).

It should be noted that the natural bitumen is still one of the most reliable waterproofing materials. High varnishes, mastics, paints and enamels take advantage of this material during their manufacturing. However, a much larger share of waterproofing and roofing materials presently belongs to artificial bitumens (of oil) and wood tar binders. A tough bitumen and tar competitor and a stunning waterproofing material was obtained on the basis of synthetic resins and polymers. As for the quality it surpasses bitumen and tar and therefore polymers are widely used in waterproof plastic. However, for waterproofing even more likely to use compounded binders. Polyshield, according to Britannia public sales statistics, a far-famed UK business involved in roof coating and roof waterproofing materials production since 1996, finds itself among the top-3 bestselling products.

By type of binder used for roofing and waterproofing materials are classified as bituminous, wood tar, wood tar bitumen, bitumen-polymer and bitumen-rubber. Basing on the physical condition and appearance of the roofing and waterproofing materials are divided into roll and sheet types, piece goods, mastics, pastes and emulsions, paints and varnishes. Each of these species has its own specific features in the composition, structure and properties.


Cement quality: the works, the properties, the types

hydraulic lime

Modern architectural companies involved in historical restorations and ambitious modern construction projects, like Wolverhampton-based Telling, largely utilising neoteric hydraulic lime and lime mortar solutions, sets tough requirements towards cement quality. It should offer good adhesion after mixing with water and sand, but only after a certain period of time (45 to 60 minutes), so it can be prepared and used diligently. According to the theory of academician Baikov, cement setting takes place in three stages. First, there is the hydration of the mixture to form particles of calcium hydroxide, which is excreted in the amorphous state, glues cement grains. The second stage is setting of the cement. Then begins the third step – crystallisation or solidification. Calcium hydroxide particles become larger, turning into a needle-like crystals that seem to be riddling the amorphous mass of calcium silicate and sealing it. It should be noted that hardening of cement is the most effective when the temperature is not too low. Therefore, in winter the builders are taking measures to heat the buildings that are under construction.

Aluminous type

A higher quality than the silicate has aluminous cement, produced with the use of clays of a low silica content. The main components of this cement are calcium aluminates. It is more expensive than silica, but it offers more advantages. So, aluminous cement better resists the action of the sea water, it hardens quickly, and moreover, the addition of water to calcium aluminate provides exothermic reaction. This is very important because it is possible to conduct the work in winter with no extra expenses on heating designs. Within hours the solidified calcium aluminate cement has a strength that some lime types achieve only in a month. Not accidently, it is called ‘stone glue’. With this cement at your disposal you can prepare the concrete, which is not afraid of water, does not burn in the fire and doesn’t lose its properties for long decades to come.

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The weak points of plasma waste disposal: the focus on feasibility

plasma waste disposal

According to experts, industrial systems, implemented on technologies using plasma heating will be significantly inferior in terms of specific capital and operating costs of conventional incineration. According to estimates, the practical implementation of such a facility for the processing of solid waste on an industrial scale would cost 600-770 pounds per 1 ton of capacity (calculated annually). At the same time, the capital cost of the plant for the traditional ayer incineration with movable grate 350-450 pounds per 1 ton/year.

In comparisons of the energy efficiency (in terms of the total energy of the combustible components produced syngas) processes and plasma autothermal gasification at temperature of 1126,85°C for one and the same type of fuel (waste), it is shown that an additional energy yield of the synthesis gas, is achieved through the plasma, with existing methods of energy conversion, even without loss of cooling, ballasting of the working mixture in the reactor, etc. It can not cover the actual costs of electricity. It was also found that a further increase in temperature is accompanied by a slight increase in the chemical energy of the synthesis gas, that is, in terms of energy is not effective. Consequently, the use of plasma technology creates additional problems that reduce reliability and efficiency of the entire plant.

Environmental benefits are also doubtful (significantly less impact on the environment and a simplified diagram of the gas cleaning). The resulting synthesis gas has to be subjected to deep cleaning of contaminants which are formed in a reducing atmosphere at high temperatures: hydrogen sulfide, ammonia, phosphine, arsine, hydrogen chloride and others. The efficiency of rapid quenching of the synthesis gas used to destroy compounds such as dioxins and furans has not yet been proven by independent studies.

Let us consider in more detail the most proven technology by Simdean Company, a UK-based plasma waste disposal and industrial waste disposal solutions expert, servicing the domestic and abroad markets. The proposed technology relies on the use of plasma heat to produce synthesis gas (which is subsequently used to generate heat and electricity), a vitrified inert slag (which is converted and inorganic waste which can then be used in industrial production), and metals.

In general, the process of recycling is organised as follows. The waste from garbage trucks are unloaded into a hopper, where they are subjected to a powerful grinding to achieve the required size. Sewage sludge is partially dried (50% RH), and the tire is cut to obtain pieces of the required size for mixing with the solid waste and other waste to the gasification process. Prepared for the processing of waste into the upper part of the gasification reactor used in the gasification technology the company offers is different from other types of gasifiers primarily in construction of plasma torches with adjustable power, located in its bottom part (relative to the gasification zone) and the presence of lumpy coke cushion that prevents mass gasified product to fall below a certain point adjustment gasifier. Due to these differences gasifier provides recycling differ considerably in their morphological and physicochemical properties. The enhanced construction defines the increased efficiency that explains the reasonability of installing the technology at large enterprises with ongoing waste processing.



The industrial-scale use of ultrasonic cleaning equipment: the technology in action


Under the influence of ultrasound of a certain intensity cavitation occurs in the liquid (occurrence and further explosion of huge number of microscopic bubbles). With the explosion of bubbles on the surface of some object immersed in the treatment solution, an enormous amount energy is released at the micro level, that leads to rapid separation of different impurities. This technology allows achieving a high degree of purification and is implemented by means of ultrasonic baths with embedded or immersed emitters. The use of ultrasound in some cases eliminates the use of chemically aggressive and environmentally harmful solutions.

The serial production largely utilises complex ultrasound washing equipment. An average system consists of nodes mounted on the modular principle, the use of which provides a broad range of technological capabilities. The nodes are combined into a mechanised or automated line of surface cleaning products after manufacturing operations. The complex is generally composed of an ultrasonic bath for cleaning, rinsing bath to finalise washing, drying chamber for transportation of clean products, automatic control and management panels.

For continuous precision cleaning of rolled products (wire, sheet, wire) a specialised ultrasonic line can be used. Cleaning and rinsing modules are fed with the washing solution and along with washing an imposition of high-power ultrasonic vibrations takes place. After washing an object is moved to a drying chamber. At the exit line, if necessary, heating of the product prior to coating, can be initiated. The line is built directly at the exit of the rolling equipment, or put to a separate production area and equipped with their own supply arrangements.

Cleaning of metal pipes from various manufacturing and operational pollution by using two sets of ultrasonic tools equipped with two channels for supplying a washing solution. Purification of the outer surface is carried out with magnetostrictive transducer from mechanical acoustical transformer of appropriate design and reflective plate on the opposite side of the pipe. Cleaning the insides of the pipe is implemented by a shell composed of an ultrasonic transmitter and an acoustic transformer converting the vibrations of the front end of the radiator into radial ones. The feed mechanism allows movement of the pipe through the nodes of cleaning the external and internal surfaces at a speed which provides the desired level of purification. At the inlet an induction heater can be installed for softening the oil and wax deposition.

To maintain cost savings and environmental procession improvement such systems can carry a variety of filtration systems and regeneration of process solutions. To supply washing modules with distilled water an industrial distiller can be used. With the advent of the technology and emergence of such innovating companies as Hilsonic, focusing on ultrasonic cleaner equipment manufacturing, the cost-efficiency of the cleaning method is pushing the use of ultrasonic cleaning equipment closer to medium and small enterprises; an obvious economical feasibility is confirmed by leasing opportunities manufacturers have started to offer.