WO2019027314A1

WO2019027314A1 - System and process for extracting bitumen from natural asphalt

Info

Publication number: WO2019027314A1
Application number: PCT/MY2017/050080
Authority: WO
Inventors: Gee Pun TONG
Original assignee: E Solvent Technologies (Hk) Limited
Priority date: 2017-07-31
Filing date: 2017-12-20
Publication date: 2019-02-07
Also published as: CN212687967U

Abstract

System and Process for Extracting Bitumen from Natural Asphalt 5 The present invention relates to a system and method for extracting bitumen from natural asphalt. The system of the present invention comprises a crushing system (100) for crushing natural asphalt, a mixing system (200) connectable to the crushing system for mixing rushed natural asphalt with demulsifying agents to form a homogenous mixture, and a separating system (300) connectable to the mixing 10 system for separating crude bitumen from the homogenous mixture. The present application also discloses a process for extracting bitumen from natural asphalt, the process comprising crushing the natural asphalt in a crusher, mixing crushed natural asphalt with demulsifying agents in a mixer connectable to the crusher to form a homogenous mixture, and separating crude bitumen from the homogenous mixture in 15 at least a thickener.

Description

SYSTEM AND PROCESS FOR EXTRACTING BITUMEN FROM

NATURAL ASPHALT

Field of the invention

The present invention relates to the extraction of bitumen. More particularly, the present invention relates to a system and process for extracting bitumen from natural asphalt. Background of the invention

Bitumen is a mixture of hydrocarbons commonly obtained as a by-product by refining crude oil, or obtained from natural deposits such as natural asphalt. Bitumen, an oil based substance, occurs naturally in the ores of natural asphalt, together with other substances such as sand and stones. Used primarily in road construction, bitumen may also be used for the coating of buildings, waterproofing, roofing applications, paint and enamels, or electrical products.

Various methods have been adapted and applied to cater to the constant and large demand for bitumen. One conventional method of demulsifying bitumen from natural asphalt is through the use of water. Natural asphalt is mixed with water, forming a mixture of oil, water, and sediments. The water and sediment components of the natural asphalt are removed, and the oil component of the natural asphalt is obtained as bitumen. Whilst proven to be effective, this method nevertheless has its drawbacks, as a large quantity of water is required in the demulsification of bitumen. Furthermore, the purity of the bitumen is compromised, as this method lacks a proper method for ensuring that the bitumen obtained from the natural asphalt is properly removed from the mixture. A second method used to demulsify bitumen from asphalt surfaces includes soaking the surface mixture in a limonene solvent at ambient temperatures. This is then followed by a separating method, where the solvent and bitumen are separated from the mixture using a centrifuge. This method further includes repeated solvent washings to remove any solvent and to obtain bitumen. However, this method is very costly to carry out. Additionally, this method is only applicable to obtaining bitumen from asphalt surfaces, such as pavements, and does not discuss a method for extracting bitumen from natural asphalt.

Another method for removing organic deposits from surfaces, particularly deposits containing asphaltenic compounds, is by the dissolution of the deposits in a solvent comprised of an aromatic hydrocarbon and an amine as described in US 3914132 A. Further, US 4108681 A describes a method of dissolving asphaltic material through the use of a liquid aromatic solvent and an additive material soluble in said liquid aromatic solvent. However, the use of solvents as discussed in both documents give rise to an increase in production cost, as solvents are relatively expensive. There is also a need to recover the solvent upon completion of the demulsification process so that the solvent can be recycled to minimalize solvent losses and consumption.

It is therefore apparent from the above that many methods have been adapted to cater to the large demand of bitumen in various industries. However, the methods as described hereinabove have limitations, and there is a need for a new approach for extracting bitumen from natural asphalt that overcomes said limitations to ensure a steady and reliable production of quality bitumen. Summary of the invention

An objective of the invention is to provide an efficient system and process for extracting bitumen from natural asphalt. Another objective of the invention is to provide a system and process for extracting demulsifying agent from tailings to minimize wastage of water and demulsifying agent.

These and other objectives of the invention are achieved through the use of a system for extracting bitumen from natural asphalt, where the system comprises a crushing system for crushing natural asphalt, a mixing system connectable to the crushing system for mixing crushed natural asphalt with demulsifying agent to form a homogenous mixture, and a separating system connectable to the mixing system for stirring the homogenous mixture to separate crude bitumen from the homogenous mixture. The system is further capable of extracting the demulsifying agent from the tailings of the homogenous mixture, for reuse of the demulsifying agent.

The present application also discloses a process for extracting bitumen from natural asphalt, the process comprising crushing natural asphalt in a crusher, mixing crushed natural asphalt with demulsifying agents in a mixer to form a homogenous mixture, and stirring the homogenous mixture in at least a thickener to separate crude bitumen from tailings of the homogenous mixture. The crude bitumen extracted from the homogenous mixture can undergo a desalting process and distilling process for refinement.

Also disclosed is a process for extracting the demulsifying agent from the tailings of the homogenous mixture, such that the final oil and water content in the solid tailings for disposal do not exceed 2% of dry solid tailings by weight and 40% respectively. The extracted demulsifying agent can be reused to reduce total costs involved and to minimize wastage.

Brief description of the drawings Figure 1 is an overview illustration of the crushing system for crushing natural asphalt for extracting bitumen according to the present embodiment.

Figure 2 illustrates the mixing system for mixing crushed natural asphalt with demulsifying agents in the present embodiment.

Figure 3 depicts the separating system for separating crude bitumen from the crushed natural asphalt according to the present embodiment.

Figure 4 illustrates the distillation system for refining crude bitumen extracted from natural asphalt according to the present embodiment.

It should be noted that Figures 1 to 4 are continuous, as illustrated in the labelled process flow. Detailed description of the preferred embodiment

The present invention will now be described in a more detailed manner in connection with the accompanying figures of the preferred embodiment. However, the present disclosure is not intended to limit the invention to the precise forms as disclosed, but rather, done so that the disclosure is thorough and complete.

The present invention relates to a system for extracting bitumen from natural asphalt, generally comprising a crushing system for crushing the natural asphalt, a mixing system for mixing crushed natural asphalt with demulsifying agents to form a homogenous mixture, and a separating system for stirring the homogenous mixture to separate crude bitumen from the homogeneous mixture.

An embodiment of the invention is illustrated in Figures 1 - 4.The crushing system 100 is referred to in Figure 1 and comprises a crusher 104, having gears with outwardly extending teeth on its periphery. Initiation of the crusher 104 generates the gears to rotate, crushing natural asphalt received from hopper 102. Utilisation of the hopper 102 provides a uniformed and smooth flow of natural asphalt to the crusher 104 by preventing the build-up of natural asphalt in the crusher 104.

A weighing device 108 connected to the crusher 104 through a conveyor belt 106 receives and weighs the crushed natural asphalt to determine the amount of crushed natural asphalt present in each cycle to ensure that the system is fully utilised and that production requirements are met. The weighing device 108 in the present embodiment is a belt weigher in the form of a circular belt.

Crushed natural asphalt is transferred from the weighing device 108 to pre-mixing machines, a planetary mixer 1 12 and subsequently a mixing tank 1 14, via a valve 1 10. The planetary mixer 1 12 comprises spinning blades which move in a circular motion for pre-mixing the crushed natural asphalt and demulsifying agent. In this embodiment, an inlet is provided by the planetary mixer 1 12 for introducing the demulsifying agent to the crushed natural asphalt received from the valve 1 10. The pre-mixing machines are generic mixing machines known in the art, and serve as preliminary mixers before the crushed natural asphalt is transferred to the mixing system 200. Utilisation of the pre-mixing machines increases and prolongs the reaction time between the demulsifying agent and the crushed natural asphalt.

The valve 1 10 aids with the transfer of crushed natural asphalt from the weighing device 108 to the planetary mixer 1 12 to enable a smooth one-way distribution of crushed natural asphalt. A buffer tank 1 16 receives and temporarily stores the crushed natural asphalt and demulsifying agents from the mixing tank 1 14 to smoothen the flow of the crushing system 100, especially if there is an excess of pre-mixture of crushed natural asphalt and demulsifying agent which exceed the capacity of the crushing system.

Referring to Figures 1 and 2, it can be seen that pump 1 18, preferably a slurry pump, connects the crushing system 100 to the mixing system 200, as illustrated in process flow 101 . In the embodiment, the slurry pump 1 18 provides an inlet for introducing additional demulsifying agent as the pre-mixture exits the buffer 1 16 and passes through the pump 1 18 to a mixer 202 of the mixing system 200. The mixer 202, preferably a heated mixer, thoroughly mixes the pre-mixture and the newly added demulsifying agent to form the homogenous mixture. The mixer 202 of the mixing system 200 is connectable to the separating system 300 through pump 302 as depicted in Figure 3. The separating system 300 comprises a thickener 304 which functions to separate the crude bitumen from the homogenous mixture by gravity sedimentation. Two additional thickeners 308, 312, are also provided in the separating system 300 to separate and extract as much oil and water from the tailings of the homogenous mixture to reduce wastage. The three thickeners 304, 308, 312 are inter-connected through pumps 306, 310a, 310b, 314, 318. The thickeners in the present embodiment can comprise a conventional thickener or a high-rate thickener, but should not be limited to as such. As the homogenous mixture enters the thickener 304 from pump 302, a rake at bottom of the tank revolves and stirs the homogenous mixture at a sufficient speed to not cause enough agitation to interfere with settlement. The contents of the homogenous mixture start to separate according to their densities, with concentrated slurry thickening and moving towards the centre of the tank 304. At the end of this separation process, three distinct layers of oil, water, and solid are formed in the thickener 304. The layer of oil in the thickener 304, crude bitumen, is extracted from the thickener 304 and through a series of devices, a buffer tank 320 and a heater 322, transferred to a desalting system 324 which refines the crude bitumen by removing any impurities such as inorganic salts, water, and/or sediments which may be present in the crude bitumen.

As previously described, the buffer tank 320 is utilised to ensure that the overall system runs smoothly. If needed, the crude bitumen is stored in the buffer tank 320 for an amount of time before it is heated in the heater 322 to facilitate with the refining process in the desalting system 324. The desalting system 324 is an electric desalting system in the embodiment, and separates the impurities from the crude bitumen through electrostatic coalescence. The desalting system 324 can comprise any of a single-stage dehydrator, a single-stage desalter, or a two-stage desalter. If further refinement is preferred, the embodiment provides a distillation system 400, connectable to the desalting system 324 of the separating system 300 through process flow 321 as illustrated on Figures 3 and 4. The distillation system 400 comprises an atmospheric distillation tower 402 and a vacuum distillation tower 406 connected though a furnace 404. A liquid ring vacuum pump is utilised by the vacuum distillation tower 406 for maintaining the negative pressure within the tower 406.

Now referring again to the separating system 300 in Figure 3, the first thickener 304 is further connectable to the second thickener 308 through pump 306, and the second thickener 308 connectable to the third thickener 312 through pump 310b. The second and third thickeners are similar to the first thickener 304, and function to separate and extract as much oil and water from the solid tailings as possible. At the end of the separation in the third thickener 312, the solid tailings are transferred to a vacuum filter 328 through a pump 326 as depicted in process flow 31 1 , and filtered before the solid tailings are disposed.

The layer of oil separated in the second and third thickener, and the layer of water separated in the first, second, and third thickener are extracted from their respective thickeners and transferred within the present system to be reused as demulsifying agents to reduce wastage and to lower production cost. Through pump 314, it can also be seen that the second thickener 308 is connectable to an ultrafilter 316, which filters the layer of water extracted from the second thickener 308 to remove any impurities. The second thickener 308 is also configured to be connectable to the planetary mixer 1 12 of the crushing system 100 as depicted through process flow 1 1 1 , so that the layer of oil extracted from the second thickener 308 can be transferred to the planetary mixer 1 12 for reuse as the demulsifying agent.

All the pumps 302, 310a, 310b, 314, 318, 326 utilised in the present embodiments are slurry pumps. In alternative form, the crusher 104 can comprise a cooling device which prevents the heat produced by the friction in the crusher from damaging the gears. Advantageously, the addition of this device in the crusher assists in enabling a smoother operation of the crusher which enhances and maximises the operation of the crusher by prolonging the lifespan of the crusher. The cooling device, however, does not alter the property or quality of the end product in any way.

In alternative form, the crusher 104 can be modified and comprise other parts instead of gears to grind, shear, or carry out other types of cutting methods to decrease the size of natural asphalt to its required dimensions. The dimensions of the natural asphalt can also be adjusted and modified accordingly.

In alternative form, the valve 1 10 is a three-way valve in the event that more than one planetary mixer 1 12 is preferred, to enable even distribution of crushed natural asphalt to the planetary mixers.

In alternative form, the belt weigher of the weighing device is adjusted to be in any form apart from a circular belt.

In alternative form, crushed natural asphalt is transferred from the crusher 104 or weighing device 108 of the crushing system 100 to the mixer 202 of the mixing system 200. In this form, mixer 202 comprises an inlet for introducing demulsifying agents to the crushed natural asphalt. In alternative form, the mixing system 200 comprises a static mixer which receives the homogenous mixture from the mixer 202 for enhancing the mixing of the homogenous mixture to improve the extraction process of bitumen from natural asphalt.

In alternative form, the separating system 300 can comprise only one thickener carrying out multiple separation processes instead of three thickeners.

It will be appreciated that the entire system of the present embodiment is controlled using a distributed control system, enabling the entire system to automated. A second aspect of the present invention relates to a process for extracting bitumen from natural asphalt according to the system of the present embodiment, generally comprising crushing the natural asphalt in a crusher 104, mixing crushed natural asphalt with demulsifying agents in a mixer 202 to form a homogenous mixture, and stirring the homogenous mixture in at least a thickener to separate crude bitumen from tailings of the homogenous mixture. The present invention further provides a process for extracting demulsifying agents from tailings of the homogeneous mixture.

Once crude bitumen is extracted from the homogenous mixture, it should be noted that the tailings of the homogenous mixture can undergo further separation processes to extract as much demulsifying agents as possible, so that the extracted demulsifying agents can be reused and added to subsequent batches of crushed natural asphalt. The process for bitumen extraction from natural asphalt according to the present embodiment may therefore vary slightly, depending on whether the process is carried out on the first batch of crushed natural asphalt, or on subsequent batches after the extraction of bitumen from a previous batch of natural asphalt has been carried out.

Prior to crushing the natural asphalt, a sample of the natural asphalt is first measured to determine the weight composition of bitumen, diesel oil, and sand of the natural asphalt. Whilst the natural asphalt is understood to contain a weight composition of 20 wt.% to 30 wt.% of high grade bitumen and diesel oil, the sample of natural asphalt is nonetheless tested using an extractor, preferably a Soxhlet extractor, to extract and determine the weight composition of bitumen and diesel oil in the natural asphalt.

Particularly, 100g of sample is placed in a thimble and loaded into the chamber of the Soxhlet extractor. The Soxhlet extractor is placed atop a flask containing an extraction solvent comprising an organic compound and a solvent. As the extraction solvent is heated, extraction solvent vapour fills the chamber of the Soxhlet extractor, causing the sample to dissolve. Then, the vapour is cooled thereafter, causing the vapour to drip back down into the flask, together with bitumen and diesel oil extracted from the dissolved sample. This is done multiple times, to ensure that all the bitumen and diesel oil has been extracted from the sample of natural asphalt. The sample is re-weighed after, with the difference in the weight of the sample before and after bitumen and diesel oil are extracted accounting for the weight composition of bitumen and diesel oil present in 100g of sample.

Then, the sample of natural asphalt is dried, removing any water present in the sample, to determine the weight composition of sand in the sample. The weight of dried sample remaining after bitumen, diesel oil, and water is removed is taken as the weight percentage of sand in 100g of the sample.

The weight composition of the natural asphalt is determined to ensure that the extraction process will be conducted at an optimum rate, as the amount of demulsifying agents added to the natural asphalt in this process is dependent on the composition of the natural asphalt.

For extraction of bitumen from the first batch of natural asphalt, the natural asphalt is crushed in a crusher 104 to a diameter of 3 cm or less. By crushing the size of the natural asphalt, the surface area of the natural asphalt for demulsifying agents to react with increases. The crushed natural asphalt is transferred from the crusher 104 and weighed to determine the amount of crushed natural asphalt present in each batch. The weight of the crushed natural asphalt is compared to the weight of the sample to determine the weight composition of bitumen, diesel oil, and sand present in the crushed natural asphalt. The weighed crushed natural asphalt is transferred to a pre-mixing device, where an amount of first demulsifying agent is added and mixed with the crushed natural asphalt for at least 10 minutes. The amount of first demulsifying agent added is dependent on the weight composition of the bitumen and diesel oil present in the crushed natural asphalt. In this particular embodiment, the weight percentages of bitumen and diesel oil as previously extracted and obtained for 100g of the sample is used as a guideline and adjusted according to the total weight of crushed natural asphalt present in the batch. Then, an amount of first demulsifying agent is added at a range of 0.5 to 1 .5 times of the adjusted weight composition of bitumen and diesel oil of the crushed natural asphalt. The reaction of the first demulsifying agent with the natural asphalt causes the temperature within the pre-mixing device to rise to a temperature of about 35°C to 40°C.

A second demulsifying agent is added to the pre-mixture of crushed natural asphalt and the first demulsifying agent at a temperature of 60°C to 95°C through a pump 118, which connects the pre-mixing device to a mixer. As the pre-mixture exits the pre- mixing device and passes through the pump 1 18, the second demulsifying agent is injected into the pump 1 18 and transferred together with the pre-mixture to the mixer 202. The amount of second demulsifying agent added is dependent on the weight composition of sand present in the crushed natural asphalt. Similarly, in this embodiment, the weight percentage of sand as previously extracted and obtained for 100g of the sample is used as a guideline and adjusted accordingly to the total weight of crushed natural asphalt present in the batch. Then, an amount of second demulsifying agent is added at a range of 1 to 1 .5 times of the adjusted weight composition of sand of the crushed natural asphalt. The pump 118 is operated at 55°C to 60°C.

The pre-mixture, now comprising crushed natural asphalt, the first demulsifying agent, and the second demulsifying agent, is mixed thoroughly in the mixer 202 operating at 60°C to 95°C. The mixer, preferably a heated agitated mixer, thoroughly mixes the pre- mixture to form an even, homogenous mixture. The homogenous mixture is mixed for about 180 minutes in the mixer 202.

The homogenous mixture is received from the mixer 202 and transferred to a thickener 304 through pump 302. The pump 302 is operated at 60°C to 95°C so that the temperature of the homogenous mixture is maintained at 60°C to 95°C to ensure that bitumen can be properly extracted from the homogenous mixture.

In the thickener 304, an amount of fresh second demulsifying agent is added again at range from 1 to 1 .5 times of the adjusted weight composition of sand present in the crushed natural asphalt. A rake in the thickener 304 stirs the homogenous mixture as it enters the thickener 304 for about 120 to 150 minutes at 60°C to 95°C, causing the homogenous mixture to separate according to its different densities. The lightest density, i.e. a layer of oil of crude bitumen, floats to the top of the thickener, followed by a layer of water, and a layer of solid tailings settling at the bottom of the thickener 304.

When the separation process is complete, crude bitumen is discharged from the thickener 304 and transferred to a desalting system 324 for refinement, where the crude bitumen undergoes a desalting process. The crude bitumen is heated to 150°C and thoroughly mixed with wash water to form an emulsion. Then, the emulsion is separated through electrostatic coalescence, removing any remaining impurities such as inorganic salts, water, or sediments. The crude bitumen is refined in the desalting system 324 for about 30 minutes. The refined bitumen obtained at the end of this can be used as a blending material for road paving, or sold to refineries for further refinement to obtain light fraction products.

After crude bitumen is extracted from the thickener 304, the layer of water and the layer of solid tailings remain in the tank 304. In order to extract remaining first and second demulsifying agents, the solid tailings in the thickener 304 undergoes a second round of separation, where it is expelled from the thickener 304 via pump 306 and transferred to a second thickener 308. Here, fresh first and second demulsifying agents are added to the thickener in similar amounts as above to maintain the ratio of demulsifying agents to crushed natural asphalt. A separation process similar to the separation process in the first thickener is carried out for about 120 to 150 minutes at 60°C to 95°C, where the contents of the solid tailings are separated according to its densities. Remaining oil and water in the solid tailings are separated and extracted to be reused as demulsifying agents. The solid tailings obtained after the second round of separation in the second thickener 308 can undergo further separation process, as many times as desired, in order to extract as much oil and water from the solid tailings. It should be noted, however, that fresh first and second demulsifying agents should be added to the thickener during each separation cycle to maximise the "extracting effect", i.e. to ensure that any and all of the oil trapped in the solid tailings are extracted to minimise wastage. Nevertheless, for the purpose of the present embodiment, the solid tailings undergo two rounds of separation, once in the second thickener, and another in the third thickener 312 via pump 31 Ob. The solid tailings obtained after the third round of separation in the third thickener 312, at this point, will be condensed to a portion of sand and water. The solid tailings are transferred to a filter 328, which filters as much water as possible from the solid tailings, before the solid tailings are disposed. The filter 328, preferably a vacuum filter, is operated at a temperature of 75°C to 85°C. It should be important to note that the disposed solid tailings has been filtered to comprise not more than 40% of water and less than 2 wt.% of oil of dry solid tailings. Evidently, the present embodiment aims to minimise wastage as much as possible before disposing of the solid phase. The water filtered from the solid phase is collected and recycled to be reused as the second demulsifying agent.

For sequential batches of bitumen extraction, the process remains relatively similar, except that recycled first and second demulsifying agents are reused. For example, instead of fresh first demulsifying agent being added to the pre-mixing device, the oil extracted from the second thickener 308 during the first batch of bitumen extraction is instead reused as the first demulsifying agent. Similarly, instead of adding fresh second demulsifying agent to the homogenous mixture in the thickener 304, water, comprising the second demulsifying agent, extracted from the second thickener 308 during the first batch of bitumen extraction is reused. The same applies to the oil and water extracted in the third thickener 312 during the first batch of bitumen extraction, and is added to the second thickener 308.

It should be important to note, however, that fresh first demulsifying agent is always added to the final round of separation (i.e. the third thickener in the present embodiment), to ensure that the "extracting effect" of the solid tailings are maximised.

Further, quality control checks are in place and carried out every few batches to ensure that the quality of the reused demulsifying agents meet the required requirements in establishing the efficiency of the extraction of bitumen from natural asphalt. All the pumps 1 18, 302, 306, 310a, 310b, 314, 318, 326 are operated at 60°C to 95°C. In the present process, the first and second demulsifying agents comprise a combination of silicate and solvent naphtha.

In an alternative process, the crushed natural asphalt is transferred to the mixer 202 from the crusher 104 or the weighing device 108, where the first and second demulsifying agents are added in the mixer 202 instead.

In an alternative process, the natural asphalt is weighed prior to being crushed. In an alternative process, the weight composition of bitumen, diesel oil, and sand in the natural asphalt are not pre-determined.

In an alternative process, the pre-mixture is stored in a buffer tank at 35°C to 40°C before being transferred to the mixer 202.

In an alternative process, the homogenous mixture is further mixed in a static mixer connected to the mixer 202 for enhancing the mixing means of the present invention.

In an alternative process, the crude bitumen is stored in a buffer tank at 90°C and heated to a temperature of 90°C to 150°C to facilitate with the desalting process before it is transferred to the in the desalting system 324.

In an alternative process, the bitumen is further refined through a distillation process. The bitumen is extracted from the desalting system 324 and heated to 190°C to 200°C before it undergoes atmospheric distillation in an atmospheric distillation tower 402. Vapour comprising of light gases formed due to the decreased pressure in the tower 402 is extracted and condensed so that it can be reused as the first demulsifying agent. The residual liquid, comprising bitumen, is withdrawn from the tower 402 and heated in a furnace to 300°C.

From the furnace 404, the residual liquid undergoes vacuum distillation in a vacuum distillation tower 406. With the pressure in the vacuum distillation tower 406 reduced to less than the vapour pressure of the residual liquid, the contents of the residual liquid are caused to separated according to its densities. A by-product, light distillate, is extracted and stored so that it can be reused as the first demulsifying agent. A second by-product, diesel oil, is extracted and can be reused as fuel for the furnace 404. The heaviest density, bitumen, is extracted for use.

It will be appreciated that the bitumen obtained at the end of the distilling process meets standard bitumen grades, and does not require further refinement.

Embodiments of the present system and process have therefore been disclosed. Through these embodiments, the limitations as previously faced by conventional methods are reduced in an efficient manner which reduces costs and decreases wastage. The embodiments should not be limited to the description above, as it will be apparent to those skilled in the art that various changes and modification may be made therein without departing from the principle of the invention or from the scope of the appended claims.

Claims

1 . A system for extracting bitumen from natural asphalt, comprising

a crushing system (100) for crushing natural asphalt,

a mixing system (200) connectable to the crushing system (100) for mixing crushed natural asphalt with a demulsifying agent to form a homogenous mixture; and

a separating system (300) connectable to the mixing system (200) for stirring the homogenous mixture to separate crude bitumen from the homogenous mixture.

2. The system according to claim 1 , wherein the separating system (300) comprises at least a thickener for stirring the homogenous mixture to separate crude bitumen from the homogenous mixture.

3. The system according to claim 1 , wherein the crushing system (100) is connectable to the separating system (300).

4. The system according to claim 1 , wherein the mixing system (200) comprises a mixer (202) for mixing crushed natural asphalt received from the crushing system (100) with the demulsifying agent to produce the homogenous mixture.

5. The system according to claim 4, wherein the mixer (202) comprises an inlet for introducing the demulsifying agent into the mixer (202) for mixing with the crushed natural asphalt.

6. The system according to claim 4, wherein the mixer (202) is a heated mixer.

7. The system according to claim 2, wherein the thickener is connectable to a desalting system (324) for refining the crude bitumen.

8. The system according to claim 1 or 7, comprising a distillation system (400) connectable to the separating system (300) for further refinement of the crude bitumen.

9. The system according to claim 8, wherein the distillation system (400) comprises any one or a combination of atmospheric distillation tower (402) and vacuum distillation tower (406) for further refinement of the crude bitumen.

10. The system according to any of the preceding claims, wherein the crushing system (100), mixing system (200), separating system (300), and distillation system (400) are connectable through pumps.

1 1 . A process for extracting bitumen from natural asphalt, comprising:

crushing the natural asphalt in a crusher (104),

mixing the crushed natural asphalt with demulsifying agents in a mixer (202) to form a homogenous mixture; and

stirring the homogenous mixture in at least a thickener to separate crude bitumen from tailings of the homogenous mixture.

12. The process according to claim 1 1 , comprising weighing a sample of natural asphalt prior to crushing the natural asphalt to determine its weight composition of crude bitumen, diesel oil, and sand.

13. The process according to claim 12, wherein crude bitumen and diesel oil is extracted from the sample using an extraction solvent and an extractor.

14. The process according to claim 13, wherein the sample is weighed after crude bitumen and diesel oil is extracted, wherein the difference in weight of the sample before and after crude bitumen and diesel oil are extracted is determined as the weight composition of crude bitumen and diesel oil in the sample.

15. The process according to claim 14, wherein the sample is dried and weighed, wherein the weight of the sample after drying is determined as the weight composition of sand in the sample.

16. The process according to claims 1 1 and 12, comprising weighing the crushed natural asphalt to determine the amount of demulsifying agents added to the crushed natural asphalt.

17. The process according to claim 16, wherein weight of the crushed natural asphalt is compared to the weight of the sample, and the weight composition of crude bitumen, diesel oil, and sand in the crushed natural asphalt is adjusted accordingly to the weight composition of crude bitumen, diesel oil, and sand in the sample.

18. The process according to claim 17, comprising mixing crushed natural asphalt with a first demulsifying agent at least once, wherein the amount of first demulsifying agent is 0.5 to 1 .5 times the weight composition of crude bitumen and diesel oil of the weighed crushed natural asphalt.

19. The process according to claim 18, comprising mixing the mixture of the crushed natural asphalt and first demulsifying agent with a second demulsifying agent at least once to form a homogenous mixture, wherein the amount of second demulsifying agent is 1 to 1 .5 times the weight composition of sand of the weighed crushed natural asphalt.

20. The process according to claim 1 1 , comprising refining the crude bitumen in a desalter.

21 . The process according to claim 1 1 or 20, comprising distilling the crude bitumen for further refinement.

22. The process according to claim 21 , wherein the crude bitumen is distilled through atmospheric distillation and vacuum distillation.

23. The process according to claims 21 or 22, wherein distillate by-products are extracted for reuse as demulsifying agent.

24. The process according to claim 1 1 , wherein natural asphalt is crushed to a diameter of 3 cm or less.

25. The process according to claim 1 1 , comprising separating the solid tailings at least once for extracting remaining demulsifying agents.

26. The process according to claim 25, wherein the extracted demulsifying agents are reused.

27. The process according to claim 25, wherein the solid tailings are filtered.

28. The process according to claim 27, wherein the filtered solid tailings comprise 2% or less of oil content of dry solid tailings by weight and 40% or less of water before it is disposed.

29. The process according to any of claims 1 1 to 28, wherein the demulsifying agents comprise a combination of silicate and solvent naphtha.