Subido por Cristian Villada

CARBONES-INFO-1

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ANÁLISIS PROXIMO DE UNA MUESTRA DECARBON OBTENIDO DE UNA MINA DE
CUCUNUBA
Yuri Astrid Espinosa 20101150018.
Jhoan Andres Samaca 20091150065.
Cristian David Villada 20101150074.
__________________________________________________________________
ABSTRACT. In the present work the next analysis of a sample of coal from a mine in
Cundinamarca was performed located in a province Ubaté, the percentage of moisture, ash
and volatile material was determined, with the following values respectively: 11.7% moisture,
19.16% ash, 21.44% volatile material.
Keywords: Percentage of moisture, ash, volatile material, coal.
__________________________________________________________________
INTRODUCTION.
Coal is a dark solid, layered and fuel,
resulting from the accumulation and burial
of plant material of the first geological eras.
These carbon deposits develop through
changes initial and subsequent biological
effects of mechanical pressure and
temperature within the sediments.
The coal is characterized as the fossil fuel
that there is a greater amount of resources,
reaching 75% of total reserves estimated.
So worth mentioning its wide geographical
distribution, knowing exploitable deposits in
almost all countries. (P 1984).
Almost all coal is used in combustion
processes and coke. Thus, on the basis of
data from primary energy consumption in
Spain in 1998, 80% coal is burned to
generate electricity or steam for industrial
and domestic use, while, although in much
smaller numbers, use in the field of iron
and steel, cement and coke is equally
significant, the rest is used in other
relatively minor activities such as the
manufacture of pigments and fillers and
water filtration.
THE CARBOGENESIS
Carbogenesis
the
process
of
transformation that is caused by carbon
from plant substances, higher plants
(mainly wood) and to a lesser extent, lower
organisms such as algae, spores or pollen
is called. This process consists of two main
stages, the biochemical state that
determines the type of coal and
geochemical or metamorphic phase that
determines the rank of coal. (Zapata,
2006).
BIOCHEMICAL PHASE
For a coal is formed, vegetable substances
from which should have been preserved
oxidation and total microbial destruction. By
this fact that is postulated that the genesis
of coal should occur in wetlands where
water deposits covered or Saturus
vegetables, limiting access of oxygen and
by inhibiting the action of microorganisms
that cause rot. This water had to be
estancanda otherwise will be plenty of
oxygen and must also be shallow to allow
growth of a significant amount of vegetable
matter.
The
decomposition
process
(limited) of these plant substances depends
on the environment in which it takes place
mainly in relation to three factors: content
of nutrients for bacteria and fungi, oxygen
and pH.
Theories exist widely accepted that
explained according to these parameters
the formation of macerals (organic
aggregates physically and distinct chemical
properties, in which the organic fraction of
the coal is distributed) and thus, different
types of existing coal . Macerals would
therefore coal constituents (in the organic
fraction). Macerals have sizes from 2
microns to several centimeters, and are not
well defined and characterized by chemical
composition uniformity in the degree of
crystallization.
Are generally considered three coal
macerals groups according to their origin:
Vitrinite produced from "wood", being
derived
from
the
main
chemical
constituents of this (cellulose and lignin). EI
decomposition of Ia "wood" is produced by
the action of aerobic bacteria near the
surface of the tank and anaerobic bacteria
to a greater depth, leading to what is
known as peat. Is the majority maceral in
existing coal (> 80%), accounting for Ias
properties coked.
The inertinite, compounds ligno-cellulosic
original had previously dehydrogenation
processes have been motivated by fire
(coking) or the biochemical action. EI
subsequent decomposition process had to
be primarily aerobic by the action of various
fungi and bacteria. This material is
commonly found very finely divided and
mixed with vitrinite.
The exinita or stems lipnitita Ias more
resistant plant substances to degradation,
such as Ias resins, cuticles, spores, pollen
and algal (with high hydrogen contents). In
this case the forming process is essentially
anaerobic, denominating putrefaction.
GEOCHEMICAL PHASE
The biochemical phase might end when
deposits were found at depths greater than
10 meters. In this relatively short period, a
million years at most, have happened in the
course of 250 to 300 million years
separating us from the Carboniferous
period, a slow transformation of organic
matter at varying depths, subject, therefore,
to changing conditions of temperature and
pressure. Is geochemical stadium, which
determines the range or metamorphic
evolution of coal. The temperature
increases with the depth of 3-5 ° C per 100
m. It is possible that these temperatures
have been sufficient for extremely slow
chemical reactions profoundly transform Ia
fossil material. It has been found (Hilt rule)
that in certain fields, coal rank increases
regularly with the depth of the layer. This
transformation
process
affects
the
properties of coal, the following effects can
be observed when the increase coal rank:
Ias aromatic structures increased.
Increased calorific value (with a small
decrease for very high rank coals).
Decreased volatile content.
Decreased oxygen content.
These facts are used to characterize the
range of coal.
Composition and structure of coal
Coal is a sedimentary rock composed
mainly of an organic fraction (maceral) and
to a lesser extent, minerals, also containing
water and gases in the submicroscopic
pores. These main organic compounds are
the result of the formation and
condensation
of
polynuclear
rings
carbocicliclos, where carbon, hydrogen and
oxygen are the basic elements and sulfur
and nitrogen are complementary.
obstructing every step of the combustion
gases, thus producing industries CocaCola wanted by the behavior of coal in
heating than other parameters, because
the coke quality produced depends on that
feature.
Furthermore, all coal industries porcesan,
holes are significantly more affected
Asphalts and byproduct gases obtained.
This explains why the content of volatile
materials is one of the most important
classification parameters in this type of
activity. It then analyzes the coal properties
specified for use in power stations,
performing also an assessment of their
importance in the functioning of these.
Testing standards.
There are many tests that support the
different systems characterization of coals;
so in recent years there has been a
transition
from
elemental
chemical
composition, as a classification criterion,
using directly related technological criteria
for the use for which it is intended carbon
(fuel or feedstock for the manufacture gas
or coke).
Thus the degree of a carbon, or economic
value is defined by the relationship
between its main characteristics or
properties and possible applications. In this
regard, the following considerations must
be:
1. It is clear that in the field of coal
combustion is the most important
parameter determined heating power in a
bomb calorimeter.
2. In the case of heat treatment, achieves
important behavior against heating. Some
species gather, others swell thereby
3. next Analysis: Includes measurement
of moisture, volatile, ash and carbon; It is
the simplest and most widespread form of
characterization of a coal as it can take
basic laboratory equipment.
Humidity is generally determined by the
percentage weight loss of a sample by
heating in an oven at 105 ° C. Above this
temperature losses appear, unimportant for
most coals chemisorbed water, but
significant to the lignite and generally much
lower the higher the fuel range. As the
heating temperature rises, the bound water
in the occasion of the beginning of
pyrolysis reactions come off.
Fuel moisture: varies greatly, depending
on conditions DEM extraction and
mechanical preparation, the time that has
been exposed to weather and atmospheric
conditions at the time of sampling. Allowing
carbon balance specific to certain
atmosphere of humidity, temperature is
obtained equilibrium moisture or humidity,
fuel property, which varies depending on
the range it contains, according to the
ASTM, are measured at 30 ° C in air
(Zapata, 2006) (P 1984) (1992 C.) (G
1987) and 97% relative humidity.
The moisture content coal purposes in
different fields:
• Carbones low end, with higher moisture
content have higher transport costs.
• High levels of humidity define the coal
mining as an inert, reducing the flame
temperature, the enthalpy change of state
with smoke evacuation and increased
consumption of auxiliaries (fans).
• A low moisture content promotes and
inhibits potential milling crowds.
Volatile content: During starting of the
combustion process is clear from the coal
volatile matter consisting of different
amounts of hydrogen, carbon oxides,
methane and other low molecular weight
hydrocarbons. The volatile content of coal
is an important property of this, providing
an indication of the reactivity and ease of
ignition. In practice, measuring the amount
of volatiles is a function of the
characteristics of the coal sample and the
selected combustion process. Here, the
test proposed by ISO determination fixed
temperature (900 ° C), the length (7 min),
and the container that has to be deposited
out of contact with air; weight loss of the
sample under these conditions is defined
as the coal volatile content.
An excessively high in volatile (over 30%)
can cause security problems in milling due
to the appearance of spontaneous
ignitions.
ash:
Is the solid residue which remains after
complete combustion of any organic matter
and the oxidation of the mineral matter in
the coal. It is never equal to the contents of
the content of mineral fuel before
combustion of substances because they
changed their ways of combination.
Among the many chemical reactions
involved are dehydration of kaolin and
gypsum, dissociation of carbonates and
pyrite oxidation. Furthermore, certain
components such as chlorides totally or
partially volatilize. The most important
chemical transformations are represented,
at least theoretically, by the reactions:
Al2O3·2 SIO2·2 H2O →Al2O3·2 SIO2 +2
H2O
CaCO3 → CaO+ CO2
2 FeS2 ++5.5 O2 → 4SO2+ Fe2O3
These reactions cause a weight loss
product with respect to the reactants, so
that, except in very rare cases, the content
of ash obtained by calcination in air is
always a measure the effect of mineral
content in the coal. This forces to normalize
the temperature and duration of the test.
Consequently, the ash quality defined coal
combustion in determining the current
contents incombustible matter. A higher
ash content, calorific value lower present
the raw coal and the higher the additional
cost of handling and treatment as well as
the potential erosion problems in the
transportation equipment and combustion.
CLASSIFICATION OF COALS
One of the most accepted classifications
for coal corresponds to the American
Society for Testing and Materials (ASTM D388-777), shown in Table 1, which is
RULES OF COAL
Although there is no standard with
standards for the quality of coal and wood
(with the exception of Resolution 123 of
1998, which standardizes the sulfur content
by region)the rules under which they
perform
laboratory
procedures
are
presented. RULES OF COAL
divided into four classes according to the
properties referred the composition of the
plants and the conditions of pressure and
temperature (degree of metamorphism)
who underwent during its formation.
(B.S.Pawlowsky,
1971).
Although there is no standard with
standards for the quality of coal and wood
(with the exception of Resolution 123 of
1998, which standardizes the sulfur content
by region)
the rules
laboratory
under which they perform
procedures are presented.
(General rules on sampling
analysis of coals, 1995)
and
Applicable documents:
a.
ASTM
Standards
(General
Standards on Sampling and analysis
of coals, 1995)
• D-86 test for the distillation of
petroleum products at atmospheric
pressure.
• D268 Guide to analyze volatile and
intermediate chemicals solvents for
use in paints and coatings and related
materials.
• D323 Test Method for Vapor
Pressure of Petroleum Products (Reid
Method).
• D525: Test method for oxidation
stability of gasoline (Induction period
method).
• D 923: Standard Test Method for
checking the electrical insulation fluid.
• D 4177: Practice for Sampling
automatically
petroleum
and
petroleum products.
• D 5854 practice for mixing and
handling
of
fuel
volatility
measurements.
Documentos aplicables:
a. Normas ASTM:
(Normas
Generales Sobre Muestreo y analisis
de carbones, 1995)
• D-86 de prueba para la destilación
de productos de petróleo a presión
atmosférica
• D268: Guía para analizar sustancias
químicas volátiles e intermedios de
disolventes para su uso en pinturas y
revestimientos
y
materiales
relacionados
• D323: Método de ensayo para la
presión de vapor de los productos de
petróleo (método Reid)
• D525: Método de ensayo para la
estabilidad a la oxidación de la
gasolina (período de inducción
método)
• D 923: Método de prueba para
comprobar el aislamiento eléctrico del
líquido
• D 4177: Práctica para el muestreo
automáticamente petróleo y sus
derivados
• D 5854 para la práctica de mezcla y
manipulación
de
combustibles
medidas de volatilidad
b.
AMERICAN
NATIONAL
STANDARDS:
• B93.19 standard method for
extracting fluid samples from lines of
a trading system with hydraulic fluid
force (for analysis of particle
contamination)
• B93.44 method for extracting fluid
samples warehouse operations with
the force of hydraulic fluid.
(General rules on sampling and
analysis of coals, 1995).
DISCUSSION AND ANALYSIS OF
RESULTS:
%𝐶𝑒𝑛𝑖𝑧𝑎𝑠 = (19.827 − 18,894) 𝑥100
%𝐶𝑒𝑛𝑖𝑧𝑎𝑠 = 93.3%
Análisis de humedad residual (ASTM
D3173)
Table 5. Determination of volatile material
Table 3. Results obtained by the
analysis of moisture.
MATERIAL
Pi
Pf
-
Crucible+
coal ( initial)
WEIGHT
(g)
Crucible
coal
+ 21.420
Pf
crucible+
coal (final)
20.805
---
Difference
0.615
0.3733
Calculation of % humedity:
%humedad = (𝑝𝑖 − 𝑝𝑓) 𝑥100
%humedad = (22.5071
− 22.1338) 𝑥100
%𝐻𝑢𝑚𝑒𝑑𝑎𝑑 = 37.33%
Table 4. Determination of cinder.
MATERIAL
WEIGHT
(g)
Pi
22.5071
Crucible
+ 22.1338
coal
(final)
110°C
difference
MATERIAL
Calculation of % MV:
Weight loss was first established.
𝑝𝑖 − 𝑝𝑓
%𝑃𝑃 =
𝑥100
𝑝𝑚
%𝑃𝑃 =
21.420 − 20.805
𝑥100
1,0000
%𝑃𝑃 =61.5 %
WEIGHT
(g)
Pi
CRUCIBLE + 19.827
COAL
Pf
CRUCIBLE + 18.894
CINDER
--
Difference
0.933
Calculation of % cinder
%𝐶𝑖𝑛𝑑𝑒𝑟 = (𝑝𝑖 − 𝑝𝑓)𝑥100
Materia volátil:
%𝑀𝑉 = %𝑃𝑃 − %𝐻𝑢𝑚𝑒𝑑𝑖𝑡𝑦
%𝑀𝑉 = 61.6 − 37.3
%𝑀𝑉 = 24.1
Table of results:
Tabla 7. Results of next analisis to coal
DESCRIPCION
RESULTADO
% Humedity
37.33
% cinder
93.3
% volatile matter
24.1
According to the results (Table 7).
The analysis is carried out on a
sample of coal assigned by the
teacher. It appears that this has a
moisture content of 37.33% indicates
that the sample corresponding to a
coal of low rank, with low heat
capacity because much of the energy
is dissipated in the enthalpy change
of state of water present in the
sample. Given this moisture content
and based on ASTM (Peña Urueña,
2011) standards is expected to peat.
Table 7 shows that the sample
contains an ash content of 93.3%
which is indicative of the vast amount
of non-combustible material present
in the sample.
By the time the sample was heated to
900 ° C was almost immediate
ignition, which is explained by the
high content of volatile matter in the
sample found in 24.1% calculated.
The analyzed sample corresponds to
a low rank coal as it has features that
allow us to classify it as lignite or peat
(Peña Urueña, 2011), this based on
their high moisture, ash, volatile
material.
CONCLUSIONS
According to the analysis results for
the next coal sample obtained is a
possible match to the type of coal
lignite or peat. However, it is
necessary to obtain greater accuracy
with the type of carbon, the final
analysis, where data are considered
in addition to proximal analysis.
Bibliography
1. Normas
generales
sobre
muestreo
y
analisis
de
carbones. (1995). Santafe de
bogota: ECOCARBON.
2. B.S.Pawlowsky.
(1971).
Determinacion of total ash
content of activated carbon.
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caracterizacion de carbones.
Medellin Facultad Nacional de
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Colombia.
4. G., P. (1987). Caracterizacion
de Carbones colombianos
Zona Checua-Lenguazaque .
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