1.1 Worldwide Air Pollution Management Market

The most urgent task regarding reducing micro-dust on the roads is “STOP” of spraying water on the road “day time”. Since the secondary micro dust as by-product, resulting from combined with sunlight and water, lessen the effect of reducing dust significantly. The second problem is treating NO$_{x}$, from car and truck. It causes critical health problems to the human body but not filtered even if flow into DPF.

Fine mode aerosol (PM2.5 or less) divided into a primary generation due to combustion and a condensation of particles in the atmosphere. It divided into ones that generated in the condensation. The finer I-mode (nuclei or Aitken) is directly discharged or a relatively large j-mode, meaning less matured (i.e., a fresh particle) produced by condensation

(accumulation) means aged particles; these two modes interact through aggregation, and it grows through condensation of gaseous precursors such as NO$_{x}$, SO$_{2}$, NH$_{3}$, etc., and is wet and dry deposited. Chemical components of the aerosol taxonomic micro modes are sulfate, ammonium salt, nitrate, natural and artificial vegetation organic carbon, elemental carbon (EC), etc., and the coarse mode component related to (KECO2015-ER03-14, 2015)⁽²⁾.

Meanwhile this black (carbon) market is growing in high speed, however world widely 8% increasing death ratio due to air pollution, which needs the most urgent research and policy. The forecast for growth of 5.2% during 2014-2019 (BCC, 2015)⁽³⁾, but BCC Research 2017, which shows more than double the expected growth rate of 64 trillion won since 2015.China invested 288 trillion-won March 2014, averagely 32 percent decrease in urban fine dust concentration over four years (KECO2015-ER03-14, 2015)⁽²⁾.

Beijing has allocated $120 billion (128 trillion won) to improve air quality, bans new thermal power plants, controlling the number of vehicles and reducing steel production capacity, but still 9 times the air pollution level based on WHO (BCC, 2015)⁽³⁾. In Japan, Nozzle-type road water spray fine dust reduction (350 m section between the Japanese National Assembly and the National Assembly Hall).

Europe reduced average AEI (Air Environmental Index) of PM2.5 to 20% by 2020. France utilize rainwater on roadside as a waste cleaning facility (Using Heavy Water Supply Facility in Roadside). Finally, the United States, the United Kingdom and Taiwan, etc.). Most of the surveys have conducted on road cleaning, mainly water-cleaning vehicles. They did significant jobs to reduce micro-dust; however, still is it the largest cause of death in the world (BCC, 2015)⁽³⁾.

1.2 Constraints for direction of the scrubber

The reason for a design of a modified Day-to-Night Spraying System in a modified method based on the side effects of the pollution. To remove the effect according to the temperature and (solar) luminance, it can generate smog, according to the increase of the solar temperature and luminance with "the second level fine dust generation" in the daytime application of the sprinkling cleaning removal method. Which increased density of NO$_{2}$ nitrogen dioxide and ozone and HCHO formaldehyde (smog) by NO$_{x}$ nitrogen oxide and SO$_{x}$ sulfur oxide in exhaust gas; see NO$_{2}$ nitric oxide (NO$_{x}$: nitric oxide, NO plus nitrogen dioxide, NO$_{2}$) (Shin, 1996)⁽⁴⁾.

Therefore, the following shape of scrubber and schedule of watering are proposed:

1) Direct road injection only at night when the concentration of fine dust is getting worse.

2) In the daytime, the internal circulation type cleaning collection performed in the circulation type cyclone scrubber.

2.1 The objectives and scope

The final goal of this research is development of composite cyclone structure utilizing reserved water in order to reduce micro dust, range from 2.5 nm to 10 nm size.

For this purpose, we develop a revised cyclone scrubber, in which having guided vane and mesh type filter. Since sprayed water clean vane and mesh type metal filter, the maintenance period and cost would be much cheaper.

In addition to that, regarding target installation and maintenance cost, over 60% reduction in the investment costs compared to existing road pollution reduction measures.

In terms of quantitative estimation, the micros dust would collect over 90% for CO, CO$_{2}$, PM, SO$_{x}$, and NO$_{x}$, in the developed 30 meter spacing columns utilizing 20 m$^{3}$ of circulating water per day. It may notable that the range of working form -20⁰C to 50⁰C due to the lessen potential of water, resultantly working 4 seasons, different with other conventional ones.

In general, if compared the gas and water in the same direction show less performance of collecting dust than in the opposite direction between dust and water, already proved in many experiments. Therefore, gravity direction (downward) spraying collects a normal efficiency Test. Regarding our spiral guide vane may show best performance, an air blower type vane with an injection pressure collecting efficiency due to their 45-degree angle spraying collision with vanes.

2.2 Comparison with conventional patents

There is at least one type of similar technology for reducing micro-dust via sprayed water. This gadget contains several similarities in terms of 1) Spraying water, 2) Providing water for cleaning and 3) inlet gas to be cleaned.

However, the following progressive differences have proved in our advanced cyclone system.

1) The proposed system could work on the roadside or in the basement as a vertical type and horizontal type.

2) The proposed system could work in the subway in a horizontal type.

3) Collecting droplet shows the maximum ratio when they meet directly (0 degree), which is 141% larger pressure value than the conventional one in which water flow upper and lower directions only.

4) The proposed patent utilizes circulating rainy water and well water, which are not used in general.

5) In fact, the hydrophilic between vane and water is not so high; hence, we add metal filter, in which dust reduced 10% more while passing through (Fig. 1). The conventional dust remover use guided vanes as well.

2.3 Process of development for composite cyclone scrubber

Two main functions of collecting micro-dust have suggested shown in Fig. (1). The contaminated gas goes in the scrubber due to the fan in outlet. Over 60% of the gas meets with three fans, which combined with water and drop to the reservoir. The reserved water pumped and move into the scrubber again. After passing the guided fans, the approximately 25% of remain gas meet with metal filter. Resultantly, over 85% contaminated gas changed to clean gas, which process will start cyclically when contaminated water drained and clean water added from waterworks, rainwater or inlet well.

Fig. 1. Connected members of Model 1

Fig. 2. The dimension of outlet fan

Therefore, the water and the sprayed metal filters are passed through the fine dust flowed in through the blower and the scrubber type cleaning device washing dust and separates water and air. The next room facility system is necessary for separating clean gas and contaminated water. The key design variables might be

1) The pores of metal filter

2) Optimal space flow shape

3) Flow velocity and air volume of fine dust

4) The length and diameter of the cleaning device

5) Comparison of air vortex and cleaning degree.

Fig. 3. Connected members of Model 1

Fig. 4. The dimension of outlet fan

14 inch CF-14D Guided vanes attached as the first circling filter, which are rotated by sprayed water and out let fan. The second filters are two metal filters cleaned by the sprayed water as well. Dimensions of outlet filter and the system of model is illustrated in Fig. 3 and Fig. 4. In this system, the following variables are considered.

The structure and location of duct do not prevent flow of water

Air duct should be filtered

Inlet emissions, e.g.CO, CO$_{2}$, NO$_{x}$, and PM, meet on the vane with spraying water in a short duration

After meeting, contaminated air should have to flow into reserved water tanks via bent.

While the above 1-4) processes, capacity of pump is important, as to be selected optimum one.

2.4. Capacity of pump

To maximize cleaning effect, the process from suction with pump to spraying to vane directly related with reduction of energy. Assembled vane, fan, circular body and outlet fan as presented in Fig. (5).