BRPI0711480A2 - process to simultaneously recover and crack / benefit oil from solids - Google Patents

Abstract

PROCESS FOR SIMULTANEOUSLY RECOVERING AND DRILLING / BENEFITING OIL FROM SOLIDS. The present invention concerns a process for recovering and cracking / improving the simultaneous quality of oil from solids such as tar sand and oil shale. With this process, several of the obstacles with the existing technology are solved, and the process improves the quality of the oil to that of a lighter product than in the existing technology, removes sulfur of the order of 40% and heavy metals of the order of 90% .

Description

"PROCESS TO SIMULARLY RECOVER AND CRACK AIR / BENEFIT OIL FROM SOLIDS"

The present invention relates to a process for recovering oil from tarred sand (also called oilseed sand) and / or oil shale and benefiting the oil in the same process.

Tar sand is found in huge quantities in many countries, the largest resources are found in Canada and consist of heavy oil and sand in natural resources at different depths. These resources have been the subject of intensive research in an effort to develop technologies for sand oil recovery. Thus, there are several different technologies.

Alberta's most important mineral resources are oil and natural gas, and they account for about 90 percent of Alberta's mining income. Alberta produces approximately two-thirds of Canada's oil and more than three-quarters of its natural gas. About half of Alberta's oil is extracted from vast tar sands, which are deposits of heavy crude oil called bitumen. Alberta's tar sands represent the largest known bitumen deposits in the world. Bituminous sands occur in three major areas of the province: the Athabasca River Valley in the northeast, the Peace River area in the north and the Cold Lake region in central eastern Alberta. Bitumen is more expensive to extract than conventional crude oil, which drains naturally or is pumped from the ground. This is because the thick black oil has to be separated from the surrounding sand and water to produce a crude oil that can be further refined.

During the 1950s and 1960s, oil deposits were discovered in other regions, such as the Peace River area and Swan Hills, south of Lesser Slave Lake. In the late sixties, the last major oil deposits were found. Bitumen, which, unlike normal crude oil found in deep reservoirs, does not have the same light fractions as these, has been evaporated for thousands of years. Bitumen thus consists of heavy molecules with a density greater than 1,000 kg / dm3 (less than 10 from API) and a viscosity 1,000 times greater than light oil. In addition, tarred sand contains sulfur above 4% by weight and hundreds of ppm with heavy metals. The content of organic matter in tarred sand can range from 5 wt.% To 20 wt.%, So extraction of tarred oil involves enormous mass transport.

Due to the bitumen composition, it has to have improved quality before it can be refined in a refinery as light crude.

Because of the economic potential of these immense resources, there are several different processes for the recovery of tar sand oil. Such technologies involve biological, solvent and thermal processes, and processes where oil is washed from the sand by overheated water.

Because of the huge amounts of sand (tailings) associated with tar sand extraction, the different processes face numerous environmental constraints.

Unlike tar sand, oil shale is shale containing organic matter known as kerogen that cannot be washed or dissolved like bitumen in tar sand. To recover oil shale oil, it has to be heated to a temperature of 500 - 600 ° C, whereby organic matter is cracked into liquid products.

For tarred sand, oil shale contains several unwanted constituents, which cause environmental restrictions. And, for technologies for recovering tar sand oil, there are several different technologies for recovering oil from shale oil.

The present invention relates to a self-sustaining energy process where several of the obstacles with existing technologies are addressed, and which, in addition to oil recovery, improves oil quality in a lighter product than any other technology. removes 40% sulfur and 90% heavy metals. In addition, the process has tailings with limited environmental restrictions, such as dry inorganic matter (sand).

The process is a fast "wet-dry" fluidized process where sand is mixed into an activated fluidized reactor with some of the organic components in the tarred sand. Flue gases remove oil from the sand, together they act as a pneumatic carrier transporting sand and its associated gases to a cyclone reactor, where the sand is separated from the gas stream, which is then routed to a condensation system. A portion of the condensed oil can be routed back into the stream through an atomizing nozzle for a second crack, whereby the process recovers and improves oil quality in one operation without the need for beneficiation units. .

To optimize collisions between particles to obtain maximum shear forces between solids, the sand stream, flue gases and hydrocarbon gases are accelerated and retarded in a rising pipe of varying diameter.

Collisions between particles give rise to mild oil hydrogenation by the sonoluminescence of microscopic vapor bubbles trapped between the colliding solid particles. When vapor bubbles are trapped between irregularities in the colliding particles, the vapor is subjected to adiabatic compression whereby the temperature and pressure in the bubbles are increased thousands of times above the overall process temperature and pressure. This causes water to enter a supercritical state where water is cracked with hydrogen and hydroxyl radicals. Hydrogen, which is absorbed by the heavy oil chains, reduces their bond, whereby the impact forces of the colliding grains can crack the molecules and the microscopic vapor bubbles "burst". Most of the hydrogen is then released and reacts back with the hydroxyl radicals in water, but some of the hydrogen causes mild hydrogenation of the product.

It is highly desirable to achieve good sand / oil mixture as soon as possible. The method described to achieve this requires the aforementioned acceleration and deceleration of the current. Traditionally, steam is the medium used to maintain solid bed fluidity and upward pipe movement. Steam, however, has a deleterious effect on very hot solids that are found in waste cracking processes. Under these conditions, vapor causes hydrothermal deactivation of the catalyst, for example in FCC crackers.

This is overcome by the present invention using the fluidized bed reactor regenerator outlet gases (CO / CO2 gases and hydrocarbons) as the solids carrier which will act as a catalyst in the oil cracking.

To have the process verified, a 2.5 χ 2.5 χ 3 m test equipment was built and located at Sintef Energy Research AS in Trondheim, Norway, with a maximum power of 125 kW.

The equipment layout is shown in figure 3.

Figure 4 shows the equipment during the test.

The energy requirement to process one kilogram of oil sand is given by:

<formula> formula see original document page 5 </formula>

Where:

xs = part by weight of sand (including metals and sulfur), eg 80%.

X0 = part and weight of oil, for example 15%. xw = part by weight of water, for example 5%. cs = sand specific heat kJ / kgK = 1 kJ / kgK. C0 = specific oil heat at operating temperature kJ / kgK = approximately 2.25 kJ / kgK. r0 = evaporative heat kJ / kg = approximately 225 kJ / kg.

dt = temperature difference between operating temperature and sand feed temperature K

H = enthalpy of water at operating temperature kJ / h = 3,500 kJ.

Operating temperature 360 0C = 633 K.

Feeding temperature 90 0C = 363 K. dt = 270 K.

Q = 516 kJ / kg and giving a test equipment capacity of 872 kg / h of sand containing 130 kg of oil giving a capacity of approximately 20 bbl / day.

The tests were performed with Athabasca River Valley deposited tar sand with the properties listed above, where the following results were obtained:

Recovered Fluidizer Oil Density: 21 API

Density of oil recovered from riser: 29.3 API.

Density of drained oil from oil condenser: 25.15 API. Coke remaining in used sand: 1.25 W%. Sulfur reduction in oil: 45%. Heavy metals reduction: 87%. Energy consumption as% of recovered oil: 9.3 = approximately 12.5 kg / oil / h = approximately USD 3.93 per bbl (oil price USD 50 per bbl).

Figure 5 shows oil sand, reclaimed oil and test sand. The process is described in detail in the simplified flow chart in figure 1.

A) shows the vertical fluidized reactor having a fluidizing mesh B positioned at a distance from the base of the vessel. The space between the base and the fluidized mesh B is a pressure chamber C) which receives the combustion gases from a combustor D) which can be activated by both recovered gas and / or oil. The flue gases will heat and fluidize the solids (sand) e) trapped in the reactor A. The accumulated flue gas pressure in the reactor will cause the trapped solids and gases consisting of the flue gases, steam and hydrocarbon gases, be transported permanently through a riser JJ into a reactor cyclone G) which is designed such that unlike ordinary cyclones, solids spin hundreds of times in a cylindrical part of the cyclone before falling into conical part H ) and back in the fluidizer.

At the base of the conical part of the cyclone, overheated vapor is injected into the cyclone by tube I) to remove hydrocarbons between the cyclone solids falling into reactor A) by means of an immersion leg.

Oil sand is injected into reactor A) by a feed system Ce) and Dd). The same amount of sand injected into reactor A must be drained from the reactor. This is done by the pipe arrangement K) where the sand is transported to a fluidizing combustor L where the remaining coke is burned by the air injection through M). Exhausted gases L) pass through a gas cleaning and heat recovery system N) before being released into the atmosphere.

The "clean" solids from L) are routed to a solid / liquid heat exchanger Z) distributed from the water supply pump Ρ). The hot water is further conveyed to a boiler Q) located on the combustor L). The boiler is producing steam where part of it is routed to a superheater R) located in the pressure chamber C) of reactor A). The overheated steam is routed to the oil vapor atomization nozzle S), the dip leg J) in the reactor cyclone H) and the dip leg T) in the separation cyclone U). Resin "clean" sand can be disposed of heat exchanger O) in a landfill as the sand will be dry and free of any volatile hydrocarbons.

Excess steam that is not overheated is routed through tube V) for the purpose of preheating the feed or to generate electricity through a steam turbine system.

From reactor cyclone G) and separation cyclone U), the gas stream is routed to a condenser W) set at 95 ° C whereby the main part of the oil gas is condensed into liquid oil. Gas is condensed through recovered oil as oil collected at the base of the condenser is pumped by pump X) through a heat exchanger Z) and resins by water distributed by pump P). From the heat exchanger Ζ), the resin oil is routed to the top of the condenser and condenses the incoming oil gases. As the oil level rises in the condenser, the product drains out of the tube (BB). Non-condensable gases and steam are routed to a second condenser (CC) which is resinated by water injected by pump P). Condensed water is drained from the condenser through the pipe DD) and is collected in a settling tank EE). In the settling tank EE), light oil converted from oil condenser CC) will be decanted through tube FF) into the product line from oil condenser W and routed to a receiver through tube AA).

Water is drained through the pipe GG) for drainage.

Non-condensable in the DC condenser) is exhausted through the HH) pipe to both the atmosphere and a gas cleaning system depending on local emission requirements.

A portion of the product is returned to riser JJ) through pipe NN) by a high pressure pump LL) to atomization nozzle S) attached to riser JJ).

Atomizing nozzle S) receives steam for atomization of superheater oil R).

Excessive combustion gases formed in the reactor that are not required to transport sand in the riser pipe JJ) can be released into the atmosphere by the reactor through the OO pipe in a gas cleaning and heat recovery system not shown.

When the reactor is heated to operating temperature by combustion D), the gas or oil supply for combustion may gradually be shut down, whereby the injected air will cause internal combustion of the hydrocarbon gases formed in reactor A) by combustion. than the process will be self-sustained by the energy extracted from the tarred sand itself. Alternatively, the combustor may be activated with a part of the recovered oil distributed by the pump LL).

To obtain the above mentioned acceleration and deceleration of the rising pipe current, this can be achieved by assigning the rising pipe various diameters. A preferred embodiment is to form a part of the risers as a Lavai nozzle, where the atomizing nozzle (s) are located at both the narrowest part of the ejector and where the ejector begins to expand. .

The whole process is a high thermal consumption process with a high energy density due to the velocity of the gas and the sand stream. Because of the process speeds, the large heat exchange between sand and oil and the low partial pressure of hydrocarbon gases caused by the combustion and steam gases, the process can operate at a temperature in the range of 300 - 500 ° C. . Out of the low thermal voltage and power consumption, this low temperature reduces the polymerization of cracked product.

Figure 2 shows an illustration of a 10,000 bbl / day plant.

Claims (9)

Process for simultaneously recovering and cracking / benefiting oil from solids, such as tarred sand and oil shale, characterized in that the oil containing solids are injected into a fluidized bed reactor, where hydrocarbons are evaporated and where the Heat for evaporation is distributed by the internal combustion of a part of the hydrocarbons in the solids, or by an external combustion, and that the combustion gases together with the evaporated hydrocarbons act as a pneumatic solids carrier and reduce the partial pressure of the hydrocarbon gases. and where the current is routed to a cyclone reactor and additionally to a solids removal separator and additionally to a condensing gas condensing system. Process for simultaneously recovering and cracking / benefiting oil from solids such as tarred sand and oil shale according to claim 1, characterized in that a portion of the product from the condensation system is routed back to the current in a rising pipe through an atomizing nozzle, whereby the solids stream acts as a cracking means by shear, heat exchange and sleep-luminescence forces. Process for simultaneously recovering and cracking / benefiting oil from solids such as tarred sand and oil shale according to claims 1 and 2, characterized in that the riser has different diameters in order to obtain acceleration, deceleration and optimized collisions between solid particles in the stream. Process for simultaneously recovering and cracking / benefiting oil from solids such as tarred sand and oil shale according to claim 1, characterized in that the temperature in the regenerator is controlled by the wet oil sand injected into the regenerator. Process for simultaneously recovering and cracking / benefiting oil from solids, such as tarred sand and oil shale according to claim 1, characterized in that the removed oil sand is routed to a fluidized combustor where the remaining coke Sand is burned by the injection of air into the combustor and where the heat released is used for steam production, and where the exhaust gas from the combustor is alternately routed to the removal reactor pressure chamber to participate with the heat and exhaust gas. fluidization for removal of oil trapped in the sand. Process for simultaneously recovering and cracking / benefiting oil from solids such as tarred sand and oil shale according to claim 1, characterized in that a portion of the removed sand is mixed with a heat recovery oil sand and sand homogenization, improving the feed in the reactor. Process for simultaneously recovering and cracking / benefiting oil from solids such as tarred sand and oil shale according to claim 1, characterized in that the fluidized bed reactor has two diameters, where the bottom of the regenerator It has a smaller diameter than the top to reduce gas velocities at the top of the regenerator. Process for simultaneously recovering and cracking / benefiting oil from solids, such as tarred sand and oil shale according to claim 1, characterized in that the sand removed in the regenerator is continuously discharged from the regenerator through a tube which Outside the regenerator is a U-shaped "water" pickup where steam or gas is injected into the tube opposite the "water pickup" for pneumatic transport of sand falling into the pickup. Process for simultaneously recovering and cracking / benefiting oil from solids such as tarred sand and oil shale according to claim 1, characterized in that a regenerator battery is arranged around a combined charging system and a combined sand receiving manifold and heat recovery fluidizer (L) and where the regenerator outlet gases share a combined sand separation system and a combined condenser configuration, and where cold condensed oil acts as a means of condensation in the oil condenser by direct contact between the hot oil gases and the cooled condensate oil.