There are two commonly known viscosity reducers
   Viscous oil viscosity reducer for oil recovery. This viscosity reducer is mainly used for heavy oil, so it is called heavy oil viscosity reducer. Due to the low content of light components, the heavy oil contains more asphaltenes and gums. High, so many heavy oils have high viscosity, high viscosity, poor flow properties, and bring great inconvenience to mining and transportation, so usually before the exploitation of heavy oil, or adding heavy oil viscosity reducing agent. Heavy oil viscosity reducing agents are mainly divided into two types: water-soluble heavy oil viscosity reducing agents and oil-soluble heavy oil viscosity reducing agents.

1. Water-soluble heavy oil viscosity reducer
    This viscosity-reducing agent is easily soluble in water, and is formulated into a certain ratio to inject into the production well to reduce the viscosity of the heavy oil and change from the natural state of the oil-in-water to the oil-in-water, thereby greatly reducing the viscosity of the heavy oil. Heavy oil mining and transportation. This viscosity-reducing agent is mainly used in the oil area where water is easily taken.

  2. Oil-soluble heavy oil viscosity reducer
The main solvent of this kind of viscosity reducing agent is thin oil, which is to use thin oil to dissolve viscosity reducing agent and inject thin oil with viscosity reducing agent into heavy oil production well to facilitate exploitation and transportation of heavy oil. This type of viscosity reducing agent is mainly used. In water-deficient oil areas, it is not possible to use water-soluble heavy oil viscosity reducers because of the lack of water in the oil area.
In summary, the exploitation of heavy oil can be accompanied by heat, and it can also be injected with chemical viscosity reducing agents. Since heat tracing is not conducive to improving the pump efficiency and the fluid surface of oil wells, the power consumption is reduced, the system pressure is reduced, and the output of single well crude oil is increased. Especially in high sand-bearing wells, due to the wettability of the emulsifier to the downhole pump, the pump speed is more coordinated. Therefore, the development of a viscosity reducing agent with a small amount and a low cost can bring about considerable economic benefits. At present, the efficiency of the viscosity reducing agent has been vigorously studied at home and abroad, and its objective economic benefits can be seen, and many of the viscosity reducing agents are not resistant. Temperature performance, however, in general, gas injection is generally required (injecting high-temperature steam into the production well), which is beneficial to lowering the viscosity. However, many viscosity reducing agents do not have resistance to temperature because they are not resistant to steam injection. Temperature viscosity reducer will lose its effectiveness, so many research units and institutions are now studying how to make the viscosity reducing agent has temperature resistance, with the deepening of research, many units have already developed a temperature resistance viscosity reduction Agent, this technology has gradually matured.

Second, the viscosity of drilling fluid
During the drilling process, due to the increase of solid content, temperature increase, salt intrusion, and calcium invasion, the drilling fluid forms a net structure or enhances the network structure, resulting in an increase in the viscosity and shear force of the drilling fluid, so that the drilling fluid is pumped very much. Difficulties, difficulty in removing cuttings or excessive stress during drilling. Therefore, a viscosity reducing agent must be added to reduce the viscosity and shear force so that it has a suitable rheology. Roughly divided into the following categories
Distributed viscosity reducer mainly includes
(1) tannins
(2) Lignosulfonates
(3) Chromium-free viscosity reducer
 2. Polymer Viscosity Reducer
(1) X-40 series viscosity reducer
(2) XY-27
(3) Sulfonated styrene maleic anhydride copolymer