SE1600275A1 - Method for drying and heating ballast (crushed rock) or asphalt recovery - carbon neutral - Google Patents

Abstract

current Method for drying and heating of ballast (crushed rock) or asphalt recycling and composition of asphalt pulp with the right temperature and quality / grain size distribution TRVKB 10/13 - Swedish Transport Administration - in a carbon-neutral and energy-efficient asphalt plant - Environmentally smart production of hot flue gas dried wood chipsDrying and heating of ballast / recycled asphalt with hot flue gases in a step oven Energy recovery by condensing said flue gases, which now contain a lot of moisture, in a tube heat exchangerDrying wood chips with hot air from 2 tube heat exchangers as a heat exchanger and a heat exchanger connected to an aerotemper or similar Energy recovery by condensing the said flue gases, which now contain a lot of moisture, in a tube heat exchangerThe flue gas condensing from two step stoves- both for ballast and wood chipsThe hot air from the flue gas condensing is used for drying raw wood chipsTi capture of the energy from the condensed water by means of a heat pumpProduction of hot air in aerotemper or similar from a heat pump that uses condensed water Drying of raw wood chips by means of said hot air

Description

Easy-Line AB - Patent application - Method for drying and heating ....... ..

Method for drying and uggheating of ballast (crushed rock) or asphalt recycling and composition of asphalt mass with the right temperature and quality / grain size distribution according to TRVKB 10/13 - Tra Trakverket - in a carbon-neutral and energy-efficient asphalt plant - Miliösmart This invention is a further patent State of the art In the area of asphalt plants, there are currently a number of problems: 1. Carbon dioxide emissions from the combustion of fossil fuels - fuel oil or LPG or natural gas. 2. Energy consumption (kWh) is very high, the same applies to the power requirement (KW or MW) 3. The efficiency is very low, given the energy consumed and the energy content of the finished asphalt mass. 4. The quality of the asphalt mass is very variable, mostly considering the grain size distribution in advance. asphalt mass type. .lag illustrates this with a flow chart according to appendix 1, comments on the ballast in the cold dosing according to appendix 2 and Description of ballast flow for asphalt plants according to appendix 3. High investment and operating costs due to many in-depth processes Asphalt pulp mainly consists of 2 ingredients - aggregate (rock crusher) and binder (approx. 5%) (bitumen).

The entire manufacturing process, which mainly consists of ballast handling, ie drying and heating of crushed rock and mixing of the asphalt mass, is coherent in the conventional asphalt plant.

In this invention, the ballast handling, which can take place around the clock, is separated from the actual mixing of the asphalt mass, which takes place in accordance with orders - that is, at any time.

In the finished asphalt mass, the ballast contains approximately 31 kWh / ton asphalt mass (bitumen is delivered to the plant at full temperature).

Approximately 6 liters (up to 7 liters) of heating oil / tonne of asphalt mass is consumed, which is approximately 60 kWh.

It gives an efficiency of 40 - S0%.

With this background, it is easy to understand that it is difficult to replace fuel oil with biofuel.

The present invention aims to solve the above-mentioned problems regarding carbon dioxide emissions, high energy consumption, high power requirements and the difficulty of meeting the quality requirements, such as the grain size distribution, as the most important parameter.

The energy efficiency is increased from 40 - 50% to more than 90%. In this asphalt plant, grain size distributions and temperatures are continuously monitored. This means that there are conditions for meeting the Swedish Transport Administration's requirements.

A method for assembling the asphalt mass to achieve the requirements is patented separately. Also called proportioning.

Easy-Line AB - Patent application - Method for drying and heating ....... ..

Processes according to the erection of an asphalt plant - appendix no. 41. Pocket for ballast (crushed rock with different grades) resp. recycled asphalt - one material at a time (at a time) Different sorts can be 0-2, 2-4, 4-8, etc. the numbers stand for max & min size in mmThe ballast sorts have gone through laboratory control especially considering the grain size distribution for resp. sorting The recycled asphalt can be either milled from roads (to adjust levels or to be replaced) or torn (normally with an excavator) which is then crushed. Laboratory inspections have been carried out both in view of the particle size distribution of the constituent ballast and the constituent content of binder (bitumen) 1a. Ballasten resp. the recycled asphalt is filled at the top and top of the furnace by means of a scoop elevator or something similar, which feeds a sloping channel to the furnace pocket, which releases the material to the first step, from where the material is fed on the furnace's other steps 2. Stepper furnace for drying and heating ballast resp. recycled asphalt, (patent pending apparatus) - the kiln is designed so that it does not change the shape of the ballast significantly - (gentle) - the grain size distribution does not change significantly - the kiln can be running 24 hours / day Appendix 5 shows the kiln's section 2a. Every other step is movable and feeds the material in the desired amount by varying the speed of movement and length of movement - the inclination of the entire oven can be adjusted and thus also the steps. 2b. At the low point of the furnace, the material is discharged to a smaller compartment from where it is let down through the combustion chamber for the gas combustion of the chips and is still spread over a flame in the combustion chamber from a chip combustion boiler. See 12c 2c. Pocket for dried material. The material is dropped over a flame in a suitable amount of 2d. The material then falls onto scrapers which discharge the material for further transport to the intended silo.

She. The flue gases from the chip combustion are led under the steps in the furnace itself to the heating steps and are released through a lock in the lower edge of the steps to pass the ballast through.

Zf. The flue gas, which has now absorbed a lot of moisture, is led from the top of the oven to a tube heat exchanger (see 3.) where the moisture is condensed - energy recovery - the condensed water is led to a container intended for this (see 4.) 3. Tube heat exchanger3a. The tube heat exchanger takes in outdoor air to the chamber, which contains tubes (pipes) with hot and humid flue gases flowing through. The moisture in the flue gases condenses in the tubes and gutters to the bottom and is then pumped to a container for condensed water (see 4). The heated outdoor air is led in a duct to a confluence point for heated air from several places (see 10.) All heated air is then used to dry raw wood fl ice in another step oven (see 8.) Easy-Line AB - Patent application - Method for drying and heating ....... .. 4. condensate tank for both flue gas condensation and condensation of moist air from wood chip drying 4a. Hot condensate from the top (warmest in the top - stratifies) of the tank is led to a single tank with a heat pump (see 5.) 4b. Colder condensate is led to the bottom by a condensate tank (coldest at the bottom - stratifies) 4c. Drain from the condensate water tank (the coldest water) which is regulated to fl so that the tank is always full.

S. Heat pump5a. Hot water from heat pump to aero-temper (6) or similar5b. Recirculation of colder water to the heat pump tank 6. Aerotemper or similar6a. hot air from aero-temper to collection point 10. 7. Pocket for raw wood fl is.7a. Bucket elevator or the like can be used, which empties into a sloping channel, which connects to a smaller container at the top (high point) of the oven, which provides the first steps of the oven with raw wood chips. Stair oven for drying wood chips - patent pending separately 8a. Every other step is movable and feeds the wood chips in the desired amount by varying the speed of movement and the length of movement - the slope can also be adjusted. 8b. The chips are fed by means of the movable steps 8c. Hot air from collection point 10. is led in under the oven's step 8d. The humid air is led to a tube heat exchanger (see 9.) 8e. Discharge of dried wood chips collected in an intermediate pocket (see 11.) 9. Tube heat exchanger - moist air from the chip drying 9a. Fresh air for tube heat exchanger 9b. Hot air from tube heat exchangers - collection point 10. above9c. Condensation water for containers intended for this - see above 4.

. Heated air collection point11. Pocket for dried wood chips 11a. Discharge of chips to incinerator11b. Feeding dried chips to a chip incinerator (see 12. and also 12b.) Easy-Line AB - Patent application ~ Method for drying and heating ....... .. 12. Chip incinerator, which may either be built with refractory bricks with a view to the high temperature or made of steel and then with air-cooled or water-cooled ducts the fireplace. The cooling air can either be led to the ballast furnace or fl the ice furnace, depending on the chip furnace, has that need or not otherwise to the ballast furnace. Fireplace bricked with refractory bricks is preferable considering that you then avoid both soot and tar and thus less care and maintenance.

The chip combustion boiler consists partly of a fireplace which can be said to be located next to the kiln itself, but also a combustion chamber, which is located along the end of the kiln at that lowest point. Throughout the furnace there is a chute, which lets in primary air for combustion. The ash from the incinerator falls into the gutter. In the gutter there are scrapers that carry both the ash and the heated material (ballast or recycled asphalt) 12a. Primary air12b. Feeding dry wood chips 12c. Secondary air 12e. Flame through the incinerator where the dried ballast is spread over the flame to be heated to the desired temperature by falling ballast ÃA. Silo for recycled asphalt - these must be properly heat insulated considering temperatures between 140 & 200 degrees Celsius BS. A number of Silos for different ballast sorting - for some sorts 2 silos (those with the largest consumption) with 2 different temperatures. Facilitates the production of pulp with the right temperature.- these must be properly heat insulated considering temperatures between 140 & 200 degrees Celsius The filling of all must take place in such a way so that separation is avoided! On the filling of silos can take place continuously, ie 24 hours / day TS. A number of silos for additives Examples of additives: - Filler both from own production and purchased e.g. lime - Cement - can be used as an adhesive, but also as a filler - Polymers - plastic balls which then melt and give certain properties - on e.g. airfield - Cellulose or other type of fiber, which absorbs bitumen to in some cases be able to hold the right proportion of bitumen according to the requirements.- etc V. Under these silos there is a trolley on rails for weighing in different types of ballast and recycled asphalt different prescription / proportioning additives. The trolley fills the mixer.

The trolley has three compartments in view of the KGO method - which means a certain order of addition for the fractions in order to both achieve a more efficient mixture and to be able to reduce the consumption of binder. Asphalt pulp is manufactured according to orders, which can be made at any time. The actual driving time for a asphalt plant can sometimes be only a few hours / day, but divided into shorter or longer times. Since the conventional asphalt plant is a completely coherent process, it means a number of starts and stops during a day - because as the asphalt mass must maintain a certain temperature, it can be difficult to achieve this requirement with regard to cooling at a standstill Easy-Line AB - Patent application - Method for drying and heating ....... ..

Patents are applied for separately for a proportioning method, which both meets the grain size distribution for the respective asphalt mass type, the right amount of additive and the right temperature. Thus guarantees the highest quality according to the requirements! Bi. Bitumen tank (binder) is added with about 5% of the weight of the asphalt mass. Adhesive tank, 1 which is either added to the binder or directly in the mixer BL. Mixer for asphalt massUnder the mixer there is another trolley on rails (usually called a dog) for emptying the mixer and filling asphalt mass silos.

AS. Asphalt pulp silos - where asphalt pulp is stored according to orders. A truck with a flatbed suitable for the purpose drives under the correct asphalt pulp silo for filling and transport to the customer.

Patents are not sought for: - Silo filling - The trolley, on rails under ballast silos, with 3 pockets in view of the KGO method - The asphalt mixer which is the same as in the conventional asphalt plant - The chip combustion boiler - there are probably enough knowledgeable on the market Easy-Line AB - Patent application Appendix 2: Comments on the ballast in the cold dosing The process begins with a number of ballast boxes for different grades 0-2mm, 2-4, 4-8, 8-12, 12-16, 16-22.These pockets are usually called the cold dosing - from here the ballast is fed out on a belt which feeds in the drying drum.

The pockets are filled with a loader directly from the crushing operation. The crushing operation takes place continuously during the day. The ballast undergoes continuous laboratory control, which b | .a. includes control of the grain size distribution for resp. sorting.

The crushers are fed continuously from the quarry itself.

Normally the crushing takes place first of a large stone, with a pre-crusher, which can be fed with an excavator or loader, directly from the so-called the ointment - freshly blasted rock. Sometimes the finer material is sorted out on the way to the actual crushing. Then there is another crushing - called intermediate crushing (step 2).

There is then a further crushing after sorting out certain sortings, such as base layer gravel (0-45, 0-32), wall gravel / wear layer (0-16 / 18) and stone flour (0-2). In the last crushing (step 3), stone flour is sorted out (0-2) and a number of short fractions, e.g. 2-4, 4-8, 8-12, 12-16, 16-22, which are primarily needed for asphalt pulp production.

In ballast handling in step 3, there may be a cubicator involved. The cubicator rounds off the grains and thus reduces the chipping.

The finer material that then arises is sorted out and gives rise to another stone flour (0-2).

It appears above that stone flour occurs on 3 different occasions.

Grain size distribution for resp. stone flour certainly varies - so should not be mixed if you want to control the grain size distribution.

In the cold dosing, there are thus different ballast sorts, which have undergone thorough laboratory control, which includes control of the grain size distribution for resp. sorting.

According to the Swedish Transport Administration's TRVKB 10/13, the grain size distribution is the most important parameter for achieving the quality of the asphalt mass. If it were so good that this material in the cold dosing would not be cold but had the tooth temperature that the finished asphalt mass should have, e.g. 160 ° C, with the help of a customized proportioning program, a proportioning program which takes into account the relative grain size distribution in resp. sorting, be able to produce asphalt mass, which meets the grain size distribution for resp. asphalt mass type according to TRVKB 10/13. .lag has developed such a proportioning program where the temperature is also included, as a single parameter. The proportioning program is very easy to handle, but thus presupposes that the relative grain size distribution is known for resp. sorting. When it comes to getting exactly the right temperature for the asphalt mass, you must have a lower and a higher temperature, available, suitable for the 2 most used ballast grades. I am applying for a patent for this proportioning program.

There are currently no suitable methods for drying and heating the asphalt ballast.

The problem is that in the existing methods, the grain size distribution is transformed and in addition the control over the crown size distribution is lost. Teams are developing an asphalt plant where they have full control over both mutual grain size distributions for resp. ballast sorting and the different ballast temperatures.

I am applying for a patent for this asphalt plant.

I patent the entire process and the included oven - separately.

[Write text] Easy-Line AB - Patent application Appendix 3: Description of ballast fl fate of asphalt plant The process begins with a number of ballast pockets for different grades O-2mm, 2-4, 4-8, 8-12, 12-16, 16-22 . These doses are usually called cold dosing. The pockets are filled with a loader directly from the crushing operation. The crushing operation takes place continuously during the day.

The ballast undergoes continuous laboratory control, which i.a. includes control of native grain size distribution for resp. sorting.

The manufacturing process is completely coherent from cold dosing up to and including filling of finished pulp silos. This means that when asphalt pulp is to be manufactured, all processes in the asphalt plant are started.

From here, the ballast is fed out on a belt, which feeds into the drying drum. Output from resp. It is also regulated so that a fairly even level is maintained in the various "hot stone pockets". The consumption of the ballast in the different hot stone pockets varies because different types of asphalt mass are produced during the day. The different types of asphalt mass have different requirements for the grain size distribution of the ballast. This means that the consumption of ballast in the hot stone pockets varies. Therefore, the feed from the different pockets in the cold dosage changes quite often. This means that the composition of the ballast fed into the dryer varies.

When the ballast has passed the drying drum, it is fed out and in to a bucket elevator which lifts the ballast up to the inspection deck. In the drying drum, the shape and size (which thus decreases) of the stone / grains changes due to drum rotation, which causes the stone to rub against each other, and "shovels / wings", which lift up and release the ballast in the center to flame from the oil burner and flue gases should be able to heat the ballast in an efficient way.You can say that the drying drum acts as a grinder.A large part of the stone flour (0-2) becomes filler and part of 2-4 changes to 0-2.This means that you get a surplus on the stone flour, which has been formed and sorted out in the previous crushing process - up to 10-20% there is no provision for and may be discarded.

The flue gas velocity is so high that filler follows the flue gases. The coarsest filler falls out in the flue gas chamber, which is located after the drying drum due to that the chamber has a larger section than the drying drum, which reduces the rate of flue gas. The coarser filler is fed to the bucket elevator and is thus mixed with the tooth-dried and heated ballast, which comes from the drying drum.

The finer filler continues to accompany the flue gases to a text filter. The textile filter has 2 sections. The sections are used one at a time. When the first section has taken up enough filler, the flue gas supply is moved to the second section. Now shake / vibrate the first section so that the filler falls off. The filler is then transported to the silo. It is important that the flue gas temperature is high enough to avoid condensation of the moisture present in the flue gases. The fine ,llret, is then fed in some way and in the right amount according to the recipe for the respective asphalt mass type, to the weighing scale.

I have mentioned before, that the feed in the cold dosage is adjusted to keep a fairly even level in the hot stone pockets. This means that the composition of the ballast, which is fed on the sight deck, varies relatively much. This means in the next step that the relative grain size distribution of the ballast passing through the sieve screens varies so that the relative grain size distribution of resp. ballast sorting varies relatively much from time to time. This means that the grain size distribution for resp. sorting varies from level to level in the hot stone pockets. Now it is easy to understand that it is almost impossible to produce even quality and even more difficult to meet the quality requirements according to the Swedish Transport Administration's TRVKB 10113 I am developing an asphalt plant where the heating of the ballast does not take place in a drying drum but in a kiln, which is not significant affects the ballast in any way.

I am applying for a patent for this asphalt plant.

I patent the entire process and the included oven - separately.