MXPA01004434A - Method of disposing of waste in a coking process - Google Patents

Abstract

A method for recycling a waste stream containing water and solids comprises (a) removing water from the waste stream to produce a second stream containing less than 60%by weight water, (b) drying the second stream to produce a waste feed charge containing less than 15%by weight water, and (c) injecting the waste feed charge into a coker during the coking cycle. The water removal can be carried out in one or more steps, and can be carried out in a vertical disk centrifuge if it is also desired to reduce the particle size of the solids fraction. The waste feed charge can be injected into a delayed coker, flexicoker, or fluid coker, and allows the recycle of solid waste into the coke.

Description

METHOD FOR THE TREATMENT OF WASTE IN A COCHIZING PROCESS FIELD OF THE INVENTION The present invention relates to a process for recycling waste, in particular petroleum waste, generated in refinery operations. More specifically, the present invention relates to the treatment and / or recycling of waste in a coking process.

BACKGROUND OF THE INVENTION The coking process Coking has been practiced for many years. The process has to do with the exposure of a feed stream for heating, which results in a thermal disintegration of heavy liquid hydrocarbons in the stream to produce gas, liquid streams of several boiling and coke logs. In this field, several processes for the production of coke are known. In a delayed coking process, a fraction of oil is heated to coking temperatures and then fed to a cylindrical coke reservoir under conditions that initiate thermal disintegration. After the disintegration of the lighter constituents, the polymerization of the aromatic structure occurs, depositing a porous mass of coke in the cylindrical reservoir. In a typical delaying coking process, the residual oil is heated by changing the heat with the liquid products of the process and then feeding a fractionating tower where any light product that may remain in the residual oil is distilled. Then the oil is pumped through a homo, where it is heated to the required coking temperature. From the oven, the hot oil is discharged at the bottom of the cylindrical coke tank. The oil undergoes thermal disintegration and polymerization over an extended period, which results in the production of hydrocarbon vapors and porous carbonaceous coke that remains in the cylindrical reservoir. The vapors leave the top part of the cylindrical tank and return to the fractionation tower, where they are split into the desired cuts. This process is continuous until the cylindrical tank is filled with porous coke. Then, the residual oil supply usually to a second parallel cylindrical reservoir, while the current is introduced through the inlet of the bottom of the first cylindrical reservoir to cool the coke. The current drains the oil without disintegrating that remains in the cylindrical tank. During the previous stage of vaporization, the mixture of water and oil vapor continues to pass to product recovery, as during the coking stage. Therefore, the spills of the vaporization are diverted to the evacuation facilities, where they are condensed and transferred to the settlement bowls. In the settlement bowls, the oil passes almost touching from the surface of the water. After cooling the steam to almost 700 ° -750 ° F, the water is introduced to the bottom of the cylindrical coke tank to complete cooling. Of course, the first portions of water are evaporated by means of hot coke. The resulting steam plus oil vapor is passed through the evacuation system for condensation and the initial distillation to separate the oil. The addition of water continues until the cylindrical tank is completely filled with water. From that moment, for a period, water is introduced to overflow the cylindrical tank with discharges that are sent to the settlement equipment to remove the entrained oil, etc.

The water settlement system also receives water from other operations in the coker, as will be described later. The clarified water produced by the settlement system provides the water to cool and to recover the coke from the cylindrical tank. The recovery of coke is done by removing the top and bottom heads of the cylindrical tank and cutting the coke with hydraulic burners. First, the hole of a vertical pilot is drilled through the mass of the coke to provide a channel to discharge the coke through the opening of the bottom. Next, a hydraulic burner is directed against the upper surface of the coke at a distance from the central discharge hole to cut the coke into pieces. The parts leave the cylindrical tank of coke through the hole of the pilot. The cross-cut burner the cylindrical tank until the coke bed is completely removed. The coke that is left varies in size from large pieces to fine particles. To a considerable extent, the fine particles are separated from the larger pieces as the coke is discharged into rapids or funnel carts, water is drained through the slots. This dispersion of fine particles in the water is processed to recover the fine particles as solid fuel, and the water returns to the system for use in cooling and cutting. In a flexible coking process, a stream of material circulates continuously between a reactor and a heater. More specifically, a feed stream feeds a bed of fluidized fuel, together with a stream of hot material that recirculates. From the reactor, a stream containing coke flows into a heating vessel, where it is heated. The hot coke stream is sent from the heater to a gasifier, where it reacts with air and steam. The product gas from the gasifier, referred to as the coke gas, which contains entrained coke particles, returns to the heater and is cooled with cold coke from the reactor to provide a portion of the reactor heating requirement. A return flow of coke that is sent from the gasifier to the heater provides the rest of the heating requirement. The hot coke gas leaving the heater is used to generate high pressure steam before being processed to clean. The coke is continuously removed from the reactor. In a fluid coking process, a fluidized fuel bed reactor is used in conjunction with a burner to provide continuous production of coke. The feed stream is introduced into a scrubber, where it exchanges heat with the superheated discharges from the reactor and condenses the heavier fraction of the hydrocarbons leaving the top of the reactor. The total reactor feed, including the fresh feed and the recycle condensate in the scrubber, is injected into a bed of fluidized coke in the reactor. The coke is placed in the fluidized coke particles, while the hydrocarbon vapors pass overhead to the scrubber. The top of the reactor is cleaned to remove the solids and the high boiling material is condensed and recycled to the reactor. The lighter hydrocarbons are sent from the scrubber to a conventional fractionation, gas compression and light ends recovery units. The heating required to maintain the reactor at a coking temperature is provided by the circulation of coke between the reactor and the burner. A portion of the coke produced in the reactor is burned with air to meet the heating requirements of the process. The excess of coke is removed from the burner and sent to storage. Sediment treatment Many refineries, chemical plants, waste water treatment plants and other industrial and municipal facilities that generate waste products in the course of their operation. For example, petroleum refining produces products or waste streams such as heavy oil sediments, biological sediments from wastewater treatment plants, activated sediments, gravity separator bottoms, storage tank bottoms, emulsion solids. of oil that include solid waste oil emulsion waste liquid and dissolved air flotation (DAF, for its acronym in English) that float from the processes of separation of flocculation, etc. The treatment of these waste products can create difficult and expensive environmental problems, basically because it is not easy to convert waste streams into more valuable, useful or ecologically harmless products. Various methods have been proposed to deal with the treatment of waste products, such as petroleum refinery sediments and other similar waste products, in an economical and more environmentally acceptable manner. A proposal to deal with petroleum sediments is described in U.S. Patent No. 3,917,564, wherein a process is described in which sediments and other wet byproducts of industrial and municipal activities are added to a delayed coke as a means of Aqueous cooling during the cooling portion of the lag coking cycle. The solid fuel portions of the by-products become part of the coke, and the non-combustible solids are distributed through the mass of the coke, so that the increase in the content of the coke ash is within the commercial specifications, in Special for fuel grade coke products. Another patent which relates to the treatment of refinery waste solids in a coking cooling stream is U.S. Patent No. 5,443,717, which describes the pretreatment of the sediment prior to injecting it into the main cooling stream. More particularly, the '717 patent describes the passage of the waste stream (sediment) through a centrifuge, where it is separated into an oil stream, a stream of water and a stream of wet sediment. The wet sediment stream is passed through an apparatus to remove the water, and then the solids to which the water is removed are fed into the main cooling stream of the coking. Another process is described in U.S. Patent No. 4,666,585, which describes a process in which petroleum pellets are recycled by adding them to the supply of the delayed coke before the cooling cycle, so that the sediment together with the feed it is subject to a delayed coking. This process has the desirable aspect of holding the sediment fuel portion of the high coking temperatures so that either the conversion to coke or the distillation of residual hydrocarbon products is given. The presence of water in the sediment tends to lower the temperature in the coking unless the compensation is made by this factor, for example, by increasing the operating temperature of the coking oven. This in turn can decrease the yield of the most desirable liquid product of the delaying coking process. In addition, because the sediment contains large amounts of water and oil, the amount of sediment that can be added to the coking feed is limited by the presence of the relatively large amount of water in the sediment. It is estimated that for each ton of water that passes through the coking unit, the coking production is reduced by approximately 4-1 / 2 tons of coking feed. In the same way, the oil in the waste is not necessary for a coking unit. It is estimated that for each ton of oil that passes through the coking unit it reduces the coking feed by approximately 1-1 / 2 tons. As described in the '585 patent, the amount of sediment in the stream is limited to a maximum of 2 weight percent. Another proposal to deal with petroleum sediments is described in Patent No. 4,874,505, in which oily sediments and other refinery waste streams are segregated into high oil waste that is injected into a late coking unit during the coking phase of the cycle and waste of high water content that is injected during the cooling phase of the lag coking cycle. This process supposedly increases the capacity of the delayed coke to process the waste and sediments of the refinery and has the potential to improve the quality of the resulting coke obtained from the process. When using this process, refinery sediments can be added at a rate of up to almost 2 bbl / ton of produced coke. The separation process adds an additional step to the process and no current follows long enough to avoid undesirably affecting the coking operation. For example, the water content of the coking current is reported to be 25%, which again results in a severe reduction in coking efficiency. U.S. Patent No. 5,009,767, describes a process similar to that of the '505 patent, with the modification that the high oil content sediment is filtered to remove the water before it is introduced into the late coke unit during the coking phase of the cycle. Although the above processes are effective in some way for the treatment of waste products, such as refinery sediments, in general they are not entirely satisfactory. For example, there is often a significant loss of valuable (organic) oil, which is either absorbed in the coke or collected in the evacuation system. With the injection of the crude oil sediment cooling cycle, there is a tendency for oily cleaning in the cylindrical coke tank, which causes volatile fuel matter (VCM) to level off in the coke to be objectively high. Likewise, when sediment is incorporated into the coke supply, both water and oil in the sediment adversely affect system efficiency by reducing coke production. Therefore, it is desired to provide a method that allows the addition of a refinery or sediment waste stream to the coking process without the disadvantages associated with said addition. The present invention significantly minimizes the disadvantages of before.

SUMMARY OF THE INVENTION The present invention provides a method for adding a refinery or sediment waste stream to the coke feed stream without the disadvantages associated heretofore with such additions. The present method involves removing sufficient water and oil from a stream that initially contains water, oil and solids so that the remaining stream can feed a coke during the coking process without adversely affecting the efficiency of said process. The present invention includes a method for producing a feed charge of processed waste to be recycled in a coking process. The waste feed load is produced by passing the waste or sediment to a separation unit, such as a centrifuge, which separates the waste into a fraction of oil, a fraction of water and a fraction of solids. It is preferable that the solids have a particle size of less than 250 microns and preferably less than 75 microns to ensure that solids do not settle during transportation to the coker.

If the waste feed charge is produced in the coker and pumped directly into the coking process, the particle size of the solids becomes less important since the waste stream can be stirred to keep the solids suspended in the coke. thick aqueous suspension. However, if the waste feed load is transported in an oil tanker to the coker, it is preferable that the particle size of the solids be less than 250 microns to avoid settling before reaching the coker . The solids fraction is sent to a mixer that emulsifies the waste and where the oil can be added to ensure the pumping of the waste feed load. Although the maximum viscosity that can be pumped depends on the equipment available, it is generally believed that the compositions have viscosities of more than 5,000 cp. at more than 150 ° F that are outside the range that can be pumped for typical pumping systems. Discharges from the mixer flow to a dryer where the water content of the waste feed load is subsequently reduced. Preferably, the water content is reduced to less than 15% by weight and it is more preferable that it be reduced to less than 3% by weight. If desired, the water content can be reduced to almost zero. It is necessary that the oil in the waste feed load be at least 30% by weight to ensure that the waste feed load can be pumped. It is preferable that solids and oil be approximately equal by weight. In a delayed coking process, the fresh coke feed is made at the bottom of the cylindrical tank. The prepared waste feed charge is fed to the top of the coking during the coking cycle, preferably after the initial amount of coke has accumulated in the cylindrical coking tank. In contrast, in a flexible coking process, the coke feed and the waste feed charge can be introduced into the upper part of the coking. During the coking process, the solids in the waste feed charge are dispersed in the produced coke to effectively recycle the waste solids fraction. The present invention allows refinery waste streams to be processed on site, to allow the direct feeding of a coking on site. In an alternate embodiment, the present invention provides a treated sediment that can be transported coking away from the site of sediment generation. Although the present invention is discussed in detail below in terms of a delaying coking process, it should be understood that it can be used to equalize the advantage in flexible coking processes and the like.

BRIEF DESCRIPTION OF THE DRAWINGS For an introduction to the detailed description of the preferred embodiments of the invention, reference will now be made to the accompanying drawings, in which: Figure 1 is a schematic diagram of the operating process of the present process invention; Figure 2 is a schematic diagram of an alternative embodiment of a coking system in which the present invention can be applied; and Figure 3 is a schematic diagram of a second alternative embodiment of a coking system in which the present invention can be applied.

DETAILED DESCRIPTION OF THE PREFERRED INCORPORATIONS Although the process of the present invention will be described with particular emphasis towards the treatment of waste products produced in the refining of oil, it must be understood that it is not so limited. For example, waste products derived from chemical processes, municipal wastewater treatment plants or other facilities that produce waste products can be treated in a coking process according to the present invention. However, the process finds a particular application in the treatment of waste products produced during the refining of oil, since the process allows the recycling of solids in the waste products and the recycling of other components of the waste products in the refinery operation. Waste Processing With initial reference to Figure 1, a preferred system for carrying out the present invention consists of a vertical disk centrifuge 10, a mixing tank 32, a dryer 40, a liquid separation system 70 and a system Coke 80. Centrifuge 10, mixer 32 and dryer 40 are used to prepare a waste feed charge for use in the coking process. The vertical disc centrifuge 10 is similar to the centrifuges described in U.S. Patent Nos. 4,810,393 and 4,931,176, both incorporated herein by reference for any purpose. The vertical disk centrifuge 0 receives a waste stream (feed) from the pipe 12. The centrifuge 10 separates the waste stream into an organic fraction (oil) that pulls the centrifuge 10 via the pipe 14, an aqueous fraction (water) which removes the centrifuge 10 via the tube 16 and a fraction of solids (solids) that the centrifuge 10 removes via the tube 18. The fraction of solids is processed to become the feed charge for recycling in the coking system 80. The water that is withdrawn via the tube 16 is substantially free of organic compounds and solids and can be recycled for later use in the refinery or, if desired, it can be sent to a waste water treatment facility. The oil leaving through the tube 4 passes through the two-way valve 20, where it can be recycled via the tube 22 for a subsequent process as well as recycled in the refinery. Alternatively, or in addition, and as will be seen below, a portion of the oil may pass via valve 20 and tube 24 for later use in the process of the present invention. Generally speaking, the fraction of solids or wet sediments left by the centrifuge 10 make up more than 50%, and almost always at least 80%, by the weight of the water, less than 15% by the weight of the oil and the solids remaining. The water that is removed in the apparatus that eliminates the water 26 is sent via the tube 28 for the treatment or for a later use. Depending on the nature of the waste, a subsequent reduction of the water content of the wet sediment or of the solid fraction leaving the centrifuge 10 via the tube 18 before a further process is desirable. In these cases, the system includes an apparatus that removes the additional water 26. The apparatus for removing water 26 can be any apparatus for separating solids and liquids as, for example, a filtration equipment. Thus, the apparatus for removing water 26 consists of a filter holder, continuous vacuum filter as cylindrical reservoir filter, disc filters, horizontal filters such as table filters, container filters and belt filters, belt fasteners, Centrifuge separators, etc. The apparatus for removing water 26 also consists of an establishment tank which allows the solids to concentrate in a thick aqueous suspension which is removed as desired.

In an alternative embodiment (not shown), the water removing apparatus 26 replaces the vertical disk centrifuge 10, in which case the water removal apparatus 26 removes water and oil from the solid fraction. In this embodiment, the fraction of solids left by the apparatus to eliminate water 26 is composed of 25-60 percent by weight of solids, 5 to 75 percent by weight of oil and 5 to 75 percent by weight. the weight of water By way of example, the fraction of solids left by the apparatus for removing the water 26 is composed of 35 percent by the weight of solids and of almost equal proportions of oil and water. The fraction of solids left by the centrifuge 10, (or the apparatus that removes the water 26 under the centrifuge 10) passes via the tube 30 to a mixing tank 32. In general, the fraction of solids to which it removes the water in this incorporation will contain less than 60% by weight of water, and preferably less than 50% by weight of water, and will also contain between 30% and 45% by weight of solids and from 5% to 20% by weight oil weight. In addition to the fraction of solids to which the water is removed, the oil is also introduced to the mixing tank 32 via the tube 34. The amount of oil that is added via the tube 34 is sufficient to produce a 1: 1 portion of solids for the oil and in any case enough so that the waste feed load can be pumped. In the mixing tank 32, the waste feed charge is subjected to a large tangential force to produce a homogenous thick aqueous suspension or an emulsion. All or a portion of the oil that is added to the mixing tank 32, as will be seen below, can be supplied via the tube 36 from the oil recovery in the subsequent process of removing water from the solids. The waste feed charge passes via the tube 38 to a dryer 40. The dryer 40 is preferably a heat exchanger as described in detail in U.S. Patent 5,439,489, which is incorporated herein by reference. As shown there, the dryer 40 is designed for the effect of heat exchange in the heating of the waste feed charge. In addition, dryer 40 is provided with agitators that introduce forced convection conditions to ensure that there are no solid settlements and to assist in efficient heating of the waste feed charge. Alternatively, the dryer 40 may be a suitable dryer capable of removing water from the waste feed charge and includes equipment to recapture low boiling hydrocarbons that evaporate during the process. These low boiling hydrocarbons can be recycled within the present system or returned to the refining system. What is also introduced to the dryer 40 via the tubes 24 and 42 is the oil recovered from the oil fraction originally separated in the centrifuge 10, thus producing a waste feed charge. The amount of oil that is added to the mixing tank 32 and to the dryer 40 is controlled to ensure that the amount of oil in the waste feed load ultimately produced is 30% to 70% by weight and preferably almost equal to the amount of oil. amount of solids in the waste feed load. Preferably, the waste feed charge is introduced into the dryer 40 at a rate that allows the sudden vaporization of water to be moderated to prevent any remaining solids from leaving the dryer 40. In the dryer 40, the water vaporization more the volatile organic liquids are conducted at a temperature of about 205 ° to 300 ° F, the vaporized water and the organic liquids pass from the dryer 40 via the tube 44 to the condenser 46, the cooling fluid passes through the condenser 46 via the tubes 48 and 50. The liquid condensed in the condenser 46 passes via the tube 52 to the separator tank 54, where the gravity separation of the water / oil mixture is performed, the water is removed via tube 56, the oil via tube 58 through valve 60 and either recycled or transferred via tube 62 back for a further process, depending on the need, to the dryer 40 via the tube 36. The heating of the heating change of the waste feed charge in the dryer 40 continues until the water content of the waste feed charge is reduced. reduce to a desired level, that is, until the waste feedstock contains less than 15% by weight of water and less than 30% by weight of liquid including water and oil, the rest are solids (generally of % to almost 70% by weight of solids). If a lower water content is desired, drying continues until the desired water content is obtained. For example, it is preferable that the waste feed charge has less than 5% by weight of water and it is better to have less than 3% by weight of water, with the remaining solids and oil in about equal proportions. It would be even better if there were zero water in the waste feed, and that the solids and oil each had 50%. The processed waste feed charge obtained in this manner is recovered from the dryer via tube 64. Coking of delay Referring now to Figure 1, the fresh coking feed of reduced crude or vacuum residue is made via tube 112 to a preheater 85, where it is preheated by the change against the gas oil products before entering the lifting zone of the bottom of the coker fractionator. The fresh coker feed is mixed with the condensed feed which is condensed in the bottom section of the corer 83 and is pumped through the heater 85, where the coking feed is rapidly heated to the desired temperature level for coke formation, the coke dylindrical deposit. Almost always the steam is injected into each of the heater coils to maintain the minimum required velocity and residence time, and to suppress the coke form in the heater tubes. In general, the delay coker operation uses at least two cylindrical tanks 86 and 87. A dylindrical tank redloaks the discharges from the furnace and converts them into coke and gas, while the coke is removed from the other cylindrical tank. The waste feedstock produced in accordance with the process of the present invention is introduced into a liquid container during the feed cycle. In the preferred embodiment, shown in Figure 1, the waste feed of tube 64 is fed to the top of one or the other of the coke cylindrical tanks 86 and 87 during the coking process. The steam at the top of the coke deposit is returned as desired via tube 88 or returned to other parts of the refinery for reuse. It is preferable, but not necessary, that the waste feedstock of the tube 64 is fed to the upper part of the coke shell and does not mix with the coke supply. In an alternate addition, the waste feed charge is fed to the tube 91 and left to the heater. Some waste feed charges tend to clog the heating equipment, such as the heater 85, but in some cases the nature of the sediments is such that the tendency to the waste is suf fi ciently low to allow the sediments to mix directly with the feed of the feed. Coquizadón either before or after the heater and then go to the bottom. Although it is shown that the waste feedstock is pumped directly from the dryer 40 and to one of the dip deposits 86, 87 during the coking process, the waste feedstock can also be transported to the tank coking equipment.

Flexible coking With reference now to Figure 2, in an "alternate embodiment" the waste feed charge can be fed continuously in a flexible coking operation. The flexible coking system 200 is composed of a fluid bed reactor 286, a liquid product scrubber 288 in the upper part of the reactor, a heating element 285, where the coke of the reactor dreulates where the coke that dreulates from the reactor is heated by means of gas and hot coke from the gasifier, a gasifier 290 a gas cooling system 292 at the top of the heater and a fine particle removal system 294. The waste feed from 500 ° to 700 ° F it is injected into the coke reactor 286 via the tube 112, where it is thermally broken to a complete record of vapor products and a coke product which is deposited in the fluidized fuel coke particles. The sensible heating, the vaporization heating and the endothermic heating of the residue breaking is provided by a circulating or hot coke stream of the heater. Cracked steam products are cooled in the scrubber tower (not shown). The heavier fractions are condensed in the scrubber 288 and, if desired, they can be redissolved in the coker reactor 286. The lighter fraedones proceed on top of the scrubber 288 to a convendonal coder (not shown) where divide into the desired cuts for the subsequent process. The coke from the reactor circulates to the heating plug 285, where it is heated by means of coke and gas from the gasifier 290. A circulating coke feed stream is sent from the heater 285 to the gasifier 290, where it reaeds at a temperature High (1500 ° to 1800 ° F) with air and steam to form a mixture of H2, CO, N2, O and H2S, together with a small amount of COS. The gas product of the gasifier referred to as the coke gas, plus the entrained coke particles, is returned to the heater 285 and cooled with cold coke from the reactor 286, to provide a portion of the heat requirement of the reactor. A return stream of coke that is sent from the gasifier 290 to the heater 285 provides the rest of the heat requirement. The hot coke gas leaving the heater 285 is used to generate high pressure steam before passing through low pressure zones 295 to remove the entrained coke particles, the remaining coke fine particles are removed in a Venturi scrubber 296. Solid-free coke gas is sent to a gas cleaning unit (not shown) to remove the H2S. According to the present invention, the waste feed of the tube 64 is fed to the scrubber 288 in the heat 285, in parallel with the conventional coker feed 112. Alternatively, the waste feed charge can be directly fed. to the scrubber 288 or to the tube 289 leaving the bottom of the coking. Once in the system, the components of the present fuel composition are incorporated into the continuous stream of material through the flexible coke. It can be noted that the coke feed and the waste feed charge can be mixed before flowing to the scrubber 288 as well as by passing the coke feed and the waste feed charge through a valve (not shown) at the entrance of the scrubber 288. Fluid coking In figure 3, a simplified system for a fluid coking process is shown. There are two main reservoirs of fluidized fuel bed; a reactor 386 and a burner 385. The heavy hydrocarbon feedstock is introduced to the scrubber 387, where it changes heating with the reactor discharges and condenses the heavier fraction of the hydrocarbons. The total reactor feed, including the fresh feed and the recycled feed condensed in the scrubber, is injected into the fluidized fuel coke bed in reactor 386, where it is thermally broken to produce lighter liquids, gas and coke. The coke is placed in the coke particles of fluidized fuel, while the hydrocarbon vapors pass through the top of the scrubber 387. The upper part of the reactor is cleaned to remove solids and the boiling material over 975 ° F is it condenses and is redressed in reactor 386. The lighter hydrocarbons are sent from the 387 scrubber to the convendonal fractionation units, gas compression and recovery of light ends. The heating required to maintain the reactor 386a at a coking temperature is supplied by the drier coke between the reactor 386 and the burner 385. A portion of the coke produced in the reactor 386 is burned with air to meet the heating requirements of the process. The excess of coke moves away from the burner 385 and is sent to storage. According to the present invention, the waste feedstock of the tube 64 can be fed to the scrubber 387, parallel to the convectional co-feed stream 112. Once in the system, the components of the present fuel composition are They incorporate the continuous flow of material through the fluid coking system. The waste stream Without limiting the process field of the present invention, waste products found in refineries can usually be treated to produce the waste feed charge that includes biological sediments from water treatment plants. waste, such as activated sediments and other oil sediments that include the bottoms of the gravity separator, the bottoms of the storage tank, the oil emulsion solids that include the emulsion solids of waste liquids, the finely dispersed solids or float of dissolved air (DAF) that floats from the separation processes of flocculation and other oil waste products from the operations of the refinery. As already mentioned, the composition of the present invention can be derived from the waste streams of the refineries. For example, such streams may include sediments from the API separator, dissolved air float, waste liquid emulsion solids, tank bottom heating change cleaning pellets, oil waste pellets from the primary side of the oil refinery. wastewater treatment system and the sediments of oil from the bottom of the tank. However, the source or feed stream for the composition does not have to be a waste stream from a refinery. For example, in many petrochemical and chemical operations, the industrial waste of paint, the waste streams, of a mainly aqueous nature, that are produced have the same or similar treatment problems as they contain hazardous solids and non-aqueous liquids. Thus, the composition of the present invention can be derived from any waste stream that contains a liquid, non-aqueous fraction, a solids fraction and an aqueous fraction, regardless of the source. Waste products (streams) that are usually treated with the process of the present invention are commonly known as sediments and are mixtures of water, organic compounds and solids. The composition of the sediments can vary widely. The oil components, as already mentioned, can consist of a thousand organic compounds ranging from hydrocarbons to other organic compounds. In general, the mixture of organic compounds is known as "oil" since, for the most part, it consists of combustible products (mainly hydrocarbons) that are or tend to be insoluble in water. The terms "oil" and "oil component" are intended to include materials that are organic in nature and are generally a mixture of water insoluble organic compounds. These organic components may include hydrocarbons, aliphatic and aromatic, as well as other organic compounds that contain oxygen, nitrogen and sulfur such as ketones, carboxylic acids, aldehydes, ethers, sulfides, amines, etc. In general, especially in the case of waste products produced in refining petroleum, hydrocarbons are the main components of organic materials. The solids in waste products or streams consist of suspended carbonaceous matter together with varying amounts of non-combustible materials including silt, sand, oxide, fine particles catalysts and others, generally inorganic materials. In general, solids are those materials in the waste stream that are not soluble either in the water phase or in the organic phase of the waste stream. The sediments of the type that are useful in the process of the present invention are produced in the course of several refining operations that include thermal breakage and catalyst processes, the change of heating and cleaning of the storage tank and in the bottoms of several units. Processes that include the API separators. In a preferred process for producing the waste feed charge, a waste stream (sediment), as described above, is treated to produce a waste feed charge containing from 30% to almost 70% by weight of solids.; from 30% to almost 70% by weight of oil, and less than 5% by weight of water. In a more preferred recorder feed charge, the load has less than 3% by weight of water with approximately equal amounts of solids and oils. A more preferred waste feedstock substantially does not contain water and contains an equal amount of oil and solids. Similarly, since one objective of the present invention is the remediation of waste solids, one achievement is to maximize the portion of solids to oil in the coke feed stream. However, as a practical problem, there are disadvantages to introducing a stream of solids that does not contain at least 30% liquid. Specifically, solid particles that are not wet when introduced into the coke tend to become trapped in air currents. Also, there is a risk that air will enter the coke if the waste feed load is not fluid enough to fill the feed tube. At present, it is expected that the optimum is that a feed stream contains approximately equal parts of solids and oil. For this reason, it is preferable to add oil to the fraction of solids. To ensure that the stream can be pumped, a minimum of about 30 percent by weight of oil is needed. Because optimum pumping requires more than 30 percent oil, it is preferable that the oil and solids frits of the final stream be approximately equal. For example, so in the most preferred stream, the water content would be virtually zero and the solids and oil may be 50 percent by weight of the stream each. If the water content of the coking feed stream is 3 per cent, the preferred oil content is 47 per cent, with the balance of the solids composition. The oil that is added to the stream of solids, preferably is oil that was obtained in the initial separation or oil that was generated in the coking process, such as condensed oils from the coking vapors or oils produced in the process of evacuadón, although any current of oil can be used. Because the size distribution of the particles of the solid fraction affects the pumping of the waste feed charge, the treatment of the waste streams, according to the present invention, is conducted to result in wear and tear. of the solid particles so that the size of the particles is reduced to produce solids in the feedstock of debris having a particle size of less than 250 microns, and preferably less than 75 microns. In general, solids in the waste stream can be treated by means of a wear method so that more than 70 percent, and preferably more than 80 percent, of the total volume of solids have a particle size of less than 250. microns. Preferentially, the solids will have a particle size distribution of Gaussian nature. Said distribution of the solids, together with the maintenance of the size of the solids in the range of particle sizes specified above, produces a less viscous and therefore more pumpable coke feed stream which produces a higher quality coke. In addition, when the waste feedstock is subjected to the establishment, such as during transportation, the smaller particles will tend to remain in a longer suspension. It has been found that the vertical disc centrifuge described above not only separates the waste stream but also acts as a wear apparatus in the sense that the size of the solids particles is reduced and the desired distribution is obtained. Also, the wear mechanism is such that the particle size distribution tends to be Gaussian in nature. The composition of the waste feedstock, because it has small particles and a relatively high content of liquids that are less polar than water, it does not become viscous, which means that it can not be pumped at room temperature. Aqueous suspensions previously used for fuels in kilns or in cement kilns have disadvantages that, because the water content is high, the solids content must be kept below 25 percent by weight in order that the suspension watery can be handled with convendonal pumps. As already mentioned, the fuel composition of the present invention contains a minimum of almost 30 percent by weight of solids and can obtain up to 70 percent by weight of solids and can still be pumped. This high load of solids is also advantageous in that it reduces the transportation and treatment costs per unit weight of solids. The treatment of the waste stream to obtain the waste feed charge may be accompanied by numerous different methods, in addition to those already described. For example, the waste stream can be treated with a common horizontal liquor to separate the large portion of water from mobile organics and solids, after which the solids are treated in a suitable manner to obtain the desired water content, particle size and distributive characteristics of particle size. Alternatively, the waste stream can be separated with techniques such as filing, decanting, extraction, etc., with solids subject to reduction in size by means of techniques such as sphere mills, hammer mills, roller mills. or any type of equipment in which the pulverization or disintegration of the solids can be achieved. The coke feed composites of the present invention may also include various other components, including dispersants and / or surfactants such as lignosuffonates. There are no heating value requirements for the waste feed charge due to its oil content, the waste feed charge has a heating capacity of at least 5,000 BTU's per pound and more often at least 10,000 BTU's per pound. . Because the present coke feed stream derived from waste is virtually free of water, the wing speed that can be fed into the coking process is limited by the desired ash content of the coke output, rather than by the amount of water that can be introduced into the coke. Typical coke specifications set an upper limit of 0.1 per cent in the content of the ash. In the coking process, one ton of solids produces 0.7 tons of ash, so the feed rate of the feed stream derived from the waste to the coking can be calculated for each operation. Although several preferred embodiments of the invention have been shown and described, modifications can be made by persons skilled in the art without departing from the spirit and teachings of the invention. The described incorporations are only exemplary, and not limiting. Many variations and modifications of the invention and apparatus described herein are possible and are within the scope of the invention. Therefore, the field of protection is not limited by the description that was established before, it is limited only by the following claims, that field includes all the equivalents of the subject of the claims.

Claims (31)

1. CHAPTER CLAIMEDICATORÍO Having described the invention, it is considered as a novelty and, therefore, the content is claimed in the following: CLAIMS 1. A method for redirecting a waste stream containing water and solids, consists of: (a) removing water from the waste stream to produce a second stream containing less than 60% by weight of water; (b) drying the second stream to produce a waste feedstock containing less than 15% by weight of water; and (c) injecting the waste feed charge into a coke during the coking step.
2. 2. The method according to claim 1, wherein the second stream is subsequently dried to produce a waste feedstock containing less than 3% by weight of water.
3. 3. The method according to claim 1 also includes mixing oil in the waste feedstock so that the waste feedstock can be pumped.
4. 4. The method according to claim 1, wherein the solids and oil are in approximately equal proportions in the waste feed charge.
5. 5. The method according to claim 1 also induces the emulsification of the second stream.
6. 6. The method according to claim 1 also includes reducing the average particle size of the solids to less than 250 microns.
7. 7. A method for rewinding the solid components of a waste stream consists of: (a) separating the solids from the waste stream to produce a solids charge; (b) add oil to the load of solids in an amount of 0.5 and 1.5 times the weight of the solids; and (c) reducing the water content of the solids to less than 15 percent by weight of the total solids charge to produce a pumpable waste feedstock.
8. 8. The method according to claim 7, also includes the step of feeding said load of feed that can be pumped to a coker during the coking step.
9. 9. The method according to claim 7, wherein the pumpable feedstock is fed to the top of a coker during the coking step.
10. 10. The method according to claim 7, wherein the water content of the pumpable waste feedstock is less than 3 percent by weight.
11. 11. The method according to claim 7 also includes the step of mixing the waste feedstock with fresh coke abbonding and injecting the mixture into a coke during the coking process.
12. 12. The method according to claim 7, wherein the oil that is added in step (b) comes from the waste stream.
13. 13. A method for recirculating the components of a waste stream containing an organic liquid component, water and solids, which consists of: (a) separating said waste stream into an organic liquid fraction, a fraction of water and a fraction of solids containing less than 60% by weight of water; (b) mixing oil with said fraction of solids to which the water was removed to produce a feed charge; (c) heating said feed charge to evaporate the water and produce a pumpable waste feedstock consisting of less than 15% by weight of water, more than 30% by weight of solids and from 30% to 70% by weight of oil; and (d) injecting said waste feed charge as feed stream into a coke during a coke operation.
14. 14. The method according to claim 13, wherein said waste feedstock comprises less than 5% by weight of water.
15. 15. The method according to claim 13, wherein said waste feed charge consists of less than 3% by weight of water.
16. 16. The method according to claim 13, also induces a second step of eliminating water between steps (a) and (b).
17. 17. The method according to claim 13, wherein said waste feed charge consists of at least 50% by weight solids.
18. 18. The method according to claim 13, wherein said waste feedstock comprises about 70% by weight solids.
19. The method according to claim 13, wherein said waste feed charge consists of almost 3% by weight of water, almost 50% by weight of solids and almost 47% by weight of oil.
20. 20. The method according to claim 13, wherein said solids and said oil components are present in said waste feed in approximately equal proportions.
21. 21. The method according to claim 13, wherein step (a) is performed with a vertical disk centrifuge.
22. 22. The method according to claim 13, wherein step (a) is performed with a liquor store.
23. 23. The method according to claim 13, wherein the coking of step (d) is a delay coke.
24. 24. The method according to claim 13, wherein the coking of step (d) is a flexible coking.
25. 25. The method according to claim 13, wherein the coking of step (d) is a fluid coking.
26. 26. The method according to claim 13, wherein step (d) comprises adding said waste feedstock to the upper part of a coke.
27. 27. The method according to claim 13 also includes the step of mixing the waste feedstock with fresh coke feed and injecting the mixture into the coke.
28. 28. The method according to claim 13, wherein said solids have a particle size of less than 250 microns.
29. 29. The method according to claim 13, wherein said solids have a particle size of less than 75 microns.
30. 30. The method according to claim 13, wherein the oil that was added in step (b) comes from the waste stream.
31. 31. The method according to claim 13 also includes reducing the size of the particles that the solids make.