Human being's effort to resolve problem of oil pollution has started ever since man comes to this world, while it has lasted a few centuries to conduct water/oil separation activity by organizations with different scientific approaches. As far as technical categorization is concerned, they are classified into two types: one is primary mechanical oil removal such as cyclone separation and air flotation etc., which feature rough handling with low accuracy. The other way makes use of absorptive character of some natural or synthetic materials such as coke, active carbon, celite and fibrous materials like PP fiber and its processed products in the forms of fiber felt and fiber ball, to transfer oil carrier to absorptive materials. This approach is called 'absorptive oil separation'.

Due to their intrinsic limitations, the traditional oil separation techniques mentioned above inevitably have certain weak points: (1) its absorptive ability decreases sharply as its carries media such as water changes from static state into the active one; (2) any absorptive material will soon become saturated, then it will not only be unable to absorb oil, but will turn itself into a second source of pollution, thus leading to an abnormal condition that oil content in outlet water is more than those in the inlet water; (3) it is a constant for oil absorptive content by any material, while oil content in the polluted water is a variable. So it is impossible to set up a quantitative design control over the absorption effect of an oil separation facility based on absorption mechanism; (4) any oil separation facility based on oil absorption mechanism is very susceptible. The variation of oil content in inlet water will immediately brings about the fluctuation of that of outlet water. As it is certain with the variation of oil content in inlet water, thus determines the instability of oil content in outlet water.

The above basic properties indicate that traditional oil separation technology are unable to reach a high level in both oil removal accuracy and process in practice and in theory, especially when instantaneous oil content is substantially higher. On the other hand, demand on the control of oil content in process media (water) is getting higher, e.g. pressure steam boiler has a demand that the oil content in its processed water must be 0,3 mg/l. Definitely this is not possible by traditional oil removal process.

Thus the oil pollution control and technical development both call for the emerge of new oil removal notion and technology. Its emerge will reflected by an oil removal system facility with following characteristics:

1. It must be sensitive enough to identify the particles in the oil and water. It is able to identify and differentiate those micro oil particles from oil-polluted water containing substantial amount of emulsified oil;
2. It can automatically set up one or more shield(s) which will allow smooth entrance of water particle while refuse oil particles during its operations;
3. Oil/water separation, removal and recovery as well as oil removal accuracy can be conducted under quantitative control;
4. It can sustain many times impact of large amount of oil content, but will not affect the set oil content in outlet water;
5. When its design is correct for related soft and hard ware, its oil blocking coefficient will reach its top value, thus enabling oil removal efficiency to reach a very high level till close to zero. It will be called 'oil removal facility by blocking' when in possession of these two functions at the same time.
And related new materials, new technology and new process are based on this 'oil removal by blocking' notion.

Bidun brand HY series oil/water automatic separation and respective recovery system is a typical example of 'oil removal by blocking' facility.

Bidun staff is a fight team guiding themselves from 'natural kingdom' to 'freedom kingdom' in water disposal field. They are determined to join with its comrades in the circle to march forward on its pass towards victory.