Wednesday, September 26, 2012

        Drilling fluids are in general complex heterogeneous mixtures of various types of base fluids and chemical additives that must remain stable over a range of temperature and pressure conditions. The properties of these complex mixtures, such as equivalent static density (ESD) and the rheological properties of the fluid mixture determine pressure losses in the system while drilling. It is often assumed that these properties and thus the equivalent circulating density (ECD) are constant throughout the duration of drilling activities. This assumption can prove to be quite wrong in cases where there
is large variation in the pressure/temperature conditions, such as in high pressure-high temperature (HPHT) wells, and deep-water drilling, where low temperature conditions are encountered very close to the sea bed.
In HPHT wells, as the total vertical depth increases, there is an increase in the bottom-hole temperature, as well as the hydrostatic head of the mud column. These two factors have opposing effects on equivalent circulating density. The increased hydrostatic head causes increase in the
equivalent circulating density due to compression. The increase in temperature on the other hand, causes a decrease in the equivalent circulating density due to thermal expansion. It is most often assumed that these two effects cancel each other out. This is not always the case, especially in high temperature, high pressure wells.
Large variations in equivalent circulating density can also occur when drilling in deep water environments where relatively cold temperatures are encountered in the riser, near the ocean bed. In deep-water wells, the seabed temperature can be as low as 30 F and hydrostatic pressures at the bottom
of the riser will be 2700 psi, with a mud density of 8.6 lb/gal and a water depth 6000-ft. The low temperature conditions can cause severe gelling of the drilling fluid, especially in oil-base muds (OBM). Failure to take this effect into account will result in underestimation of the equivalent circulating density of the drilling fluid.
Errors in the estimation of equivalent circulating density have an especially disastrous effect when drilling through formations with a small gap between pore pressure, and the pressure at which the formation will fracture. In such cases, the margin for error is very small and thus, the equivalent
circulating density must be estimated precisely. Disregarding pressure and temperature effects in this case can lead to greater probability for the occurrence of kicks, and blow-outs due to under-balanced pressure or fluid loss to the formation (lost circulation and formation damage) due to
overbalance pressure. Various experimental studies have also shown drilling fluid rheology to . Rheological parameters be very pressure and temperature dependent such as viscosity and yield stress affect frictional pressure losses during the
flow of drilling fluids. Failure to take into account the dependence of these parameters on temperature-pressure conditions can result in obtaining erroneous values for equivalent circulating density, which takes into account the hydrostatic head of the drilling fluid as well as the pressure loss it
experiences during flow.
The focus of this research is to study the effect of pressure and temperature on equivalent static density as well as equivalent circulating density of drilling fluids.

Numerous publications have dealt with the behavior of equivalent static density of drilling fluids in response to variations in pressure temperature conditions. Various models have been proposed in order to characterize this relationship, with some models being empirical in nature,
and some being compositional. The compositional model characterizes the volumetric behavior of drilling fluids based on the behavior of the individual constituents of the drilling fluid. Hence, prior knowledge of the composition of the drilling fluid is required for application of the compositional model.
In the compositional model, the density of any solids content in the drilling fluid is taken to be independent of temperature and pressure. It is assumed that any change in density is due to density changes in the liquid phases. It is also assumed that there are no physical and/or chemical interactions between the solid and liquid phases in the drilling fluid, or that the solid phase is inert. Hoberock et al proposed the following compositional model for equivalent static density of drilling fluids.

ρο1, ρw1 = density of oil and water at temperature T1 and pressure P1, respectively
ρο2, ρw2 = density of oil and water at temperature T2 and pressure P2, respectively
f vo, fvw, fvs, fvc = fractional volume of oil, water, solid weighting material, and chemical additives, respectively .
P1, P2 = pressure at reference and condition “2”
T 1, T2 = temperature at reference and condition “2”
Application of the compositional model requires some knowledge of how the densities of each liquid phase in the mud, usually water and some type of hydrocarbon, change with changes in temperature and pressure. The static mud density at elevated pressure and temperature can be predicted
from knowledge of mud composition, density of constituents at ambient or standard temperature and pressure, and density of liquid constituents at elevated temperature and pressure.
Peters et al applied the Hoberock et al compositional model successfully to model volumetric behavior of diesel-based and mineral oil- based drilling fluids. In their study, they measured the density of the individual liquid components of each drilling fluid at temperatures varying from 78-350 F and pressures varying from 0-15,000 psi. Using this data in conjunction with Hoberock et al’s compositional model, they were able to predict the density of the drilling fluids at the elevated temperature-pressure conditions.
The model predictions yielded an error of <1 and="and" examined.="examined." of="of" over="over" p="p" pressure="pressure" range="range" temperature="temperature" the="the">
Sorelle et al proposed equations expressing the relationship between water and hydrocarbon (diesel oil No. 2) densities, and temperature/pressure for use with the compositional model with some success. Kutasov analyzed pressure-density-temperature behavior of water and proposed a similar
equation, which was reported to yield very low error in predicting water densities in the HTHP region.
Isambourg et al proposed a nine-parameter polynomial model to describe the volumetric behavior of the liquid phases in drilling fluids, which is applicable in the range of 14.5-20,000 psi and 60-400 F. This model characterizes the volumetric behavior of the liquid phases in the drilling fluid with respect to temperature and pressure, and is applied in a similar compositional model to that proposed by Hoberock et al. The model also assumes that all volumetric changes in the drilling fluid is due to the liquid phase, and application of the model requires a very accurate measurement of the reference mud density at surface conditions.
Kutasov proposed an empirical equation of state (EOS) model for drilling fluids to express the pressure-density-temperature dependent relationship. As is the case for the compositional model, mud density using Kutasov’s empirical equation of state is evaluated relative to its density at standard conditions (p= 14.7 psi, T = 60 oF). He applied the equation of state with a temperature-depth relationship in order evaluate hydrostatic pressure and equivalent static density as a function of depth.
Babu9 compared the accuracy of the two compositional models proposed by Sorelle et al4 and Kutasov8 respectively, and the empirical model proposed by Kutasov8 in predicting the mud weights for 12 different mud systems. The test samples consisted of 3 water based muds (WBM), 5
OBM’s formulated using diesel oil No. 2, and 4 OBM’s formulated using mineral oil. Babu9 found that the empirical model yielded more accurate estimates for the pressure-density-temperature behavior of a majority of the muds over the range of measured data more accurately than the compositional model. He also concluded that the empirical model has more practical application because unlike compositional models, it is not hindered by the need to know the contents of the drilling fluid in question.
Drilling fluids contain complex mixtures of additives, which can vary widely with the location of the well, and sometimes with different stages in the same well. This was especially apparent in the behavior of the drilling fluids prepared with diesel oil No. 2. Different oils available under the category of diesel oil No. 2 that were used in the preparation of OBM’s can exhibit different compressibility and thermal expansion characteristics, which were reflected in the pressure-density-temperature dependent behavior of the fluids prepared with them.
Research has also been reported on characterizing drilling fluid rheology at high temperature/high pressure conditions. Rommetveit et al approached their analysis of shear stress/shear rate data at high temperature and pressure by multiplying shear stress by a factor which depends on pressure, temperature and shear rate. Coefficients of this multiplying factor are fitted to shear stress/shear rate data directly without extracting rheological parameters such as yield stress first. This eliminates the need to characterize the behavior of each rheological parameter relative to pressure and temperature changes. In essence, they obtain an empirical model in which the effects of variation in all rheological parameters that describe fluid flow behavior are lumped together.
Another approach to the analysis of temperature and pressure effects on drilling fluid rheology is to consider the effect of temperature and pressure changes on each rheological parameter that describes the behavior of the fluid. The two most common models3 considered for such an analysis are the
Herschel-Bulkey/Power law model and the Casson model which is an acceptable description of oil based mud rheology. Of these two models, the Herschel-Bulkley model is the most robust, as it is a three parameter model as opposed to the Casson model which is a two parameter model. In the
analysis performed by Alderman et al on shear stress/shear rate data, the Herschel-Bulkley/Power and Casson models were considered. The behavior of each rheological parameter in these models with respect to changes in temperature and pressure was investigated. They studied a range of fluids covering un-weighted and weighted bentonite water-based drilling fluids with
and without deflocculant additives.
In order to estimate equivalent circulating density, it is important to take into account the effects of temperature and pressure on fluid rheology. Two methods are proposed to accomplish this by Rommetveit et al. They propose a stationary or static method and a dynamic method. In both methods, the contributions of hydrostatic and frictional pressure losses in high pressure/high temperature wells to the equivalent circulating density were considered. The variation in temperature vertically along the well bore is taken into account for both models, and drilling fluid properties are allowed to
vary relative to temperature.
The dynamic method however, also takes into account transient changes in temperature i.e. change in temperature over time. This effect is especially important in the case where circulation has been stopped for a significant amount of time. The drilling fluid temperature will begin to approach the temperature of the formation. Once circulation commences again as shown in Fig. 1.1, the lower part of the annulus will be cooled by cold fluid from the drill string and the upper part of the annulus will be warmed by hotter fluid coming from the bottom-hole. During this transient period, fluid
density and rheological characteristics can change rapidly due to rapid changes in temperature. Research on this effect is still at a very early stage and will not be taken into account during this study.

Figure 1.1- Schematic Diagram of Fluid in the Well bore at the Start of Circulation
Alderman et al performed rheological experiments on water based drilling fluids over a range of temperatures up to 260 oF and pressures up to 14,500 psi, using both weighted and unweighted drilling fluids. Rheograms were obtained for the water based drilling fluids, holding temperature constant
and varying pressure, and vice versa. It was found that the Herschel-Bulkley model yielded the best fit to the experimental data. Other models that were investigated are the Bingham plastic model, and the Casson model which some authors argue is the best model for characterizing oil-based drilling fluid
For the Herschel-Bulkley model, it was found that the fluid viscosity at high shear rates increased with pressure to an extent, which increases with the fluid density, and decreases with temperature in a similar manner to pure water. Alderman et al found the yield stress to vary little with pressure- temperature conditions. The yield stress remained essentially constant with respect to temperature until a characteristic threshold temperature is attained.
This threshold temperature was found to depend on mud composition. Once this threshold is reached, the yield stress increases exponentially with 1/T. Alderman et al also found that the power law exponent increased with temperature, and decreased with pressure. This lead them to conclude that
the Casson model will become increasingly inaccurate at these two extremes, that is, at high temperature and low pressure.
The estimation of ECD under high temperature conditions requires knowledge of the temperatures to which the drilling fluid will be subjected to downhole. As the fluid is circulated in the wellbore, heat from the formation flows into the wellbore causing the wellbore fluid temperature to rise. This
process is more pronounced in deep, hot wells where the temperature difference between the formation and the well-bore fluid is greater. The process is very dynamic at early times, that is, at the commencement of circulation, with great changes in fluid temperature occurring over small
intervals of time.
There are two major methods for estimating the down-hole temperature of drilling fluid. The first is the analytical method. This method assumes constant fluid properties. Ramey solved the equations governing heat transfer in a well bore for the case of hot-fluid injection for enhanced oil recovery. His solution permits the estimation of the fluid, tubing and casing temperature as a function of depth. He assumed that heat transfer in the well bore is steady state, while heat transfer in the formation is unsteady radial conduction.
Holmes and Swift solved the heat transfer equations analytically for the case of flow in the drillpipe and annulus. They assumed the heat transfer in the wellbore to be steady state. However, they used a steady-state approximation to the transient heat transfer in the formation. They justified
this assumption by asserting that the heat transfer from the formation is negligible in comparison to the heat transfer between the drill pipe and annular sections due to the low thermal conductivity of the formation.
Arnold also solved the heat transfer equations analytically for both the hot-fluid injection case and the fluid circulation case. However, in circulation case, he did not assume steady state heat transfer in the formation. He represented the transient nature of heat flow from the formation with a dimensionless time function that is independent of depth16. Kabir et al also solved a similar set of equations, but for the case of flow down the annulus and up the drill pipe. They also assumed transient heat flow in the
formation, and evaluated a number of dimensionless time functions.
The second method of estimating fluid temperature during circulation involves allowing the fluid properties such as heat capacity, viscosity, and density to vary with the temperature conditions. This method involves solving the governing heat transfer equations numerically using a finite difference
scheme. Marshal et al created a model to estimate the transient and steady-state temperatures in a well bore during drilling, production and shut-in using a finite difference approach.
Romero and Touboul created a numerical simulator for designing and evaluating down-hole circulating temperatures during drilling and cementing operations in deep-water wells. Zhongming and Novotny developed a finite difference model to predict the well bore and formation transient temperature behavior during drilling fluid circulation for wells with multiple temperature gradients and well bore deviations. 

Monday, June 28, 2010

Thermoreversible gelling agents

Gel formed on cooling. Molecules undergo a coil-helix transition followed by
aggregation of helices.
Gel formed on cooling. Molecules undergo a coil-helix transition followed by
aggregation of helices.
Kappa Carrageenan
Gel formed on cooling in the presence of salts notably potassium salts. Molecules
undergo a coil-helix transition followed by aggregation of helices. Potassium ions bind specifically to the helices. Salts present reduce electrostatic repulsion between chains promoting aggregation.
Iota Carrageenan
Gel formed on cooling in the presence of salts. Molecules undergo a coil-helix transition followed by aggregation of helices. Salts present reduce electrostatic repulsion between chains promoting aggregation.
Low methoxyl (LM) pectin
Gels formed in the presence of divalent cations, notably calcium at low pH (3±4.5).
Molecules crosslinked by the cations. The low pH reduces intermolecular electrostatic repulsions.
Gellan gum
Gels formed on cooling in the presence of salts. Molecules undergo a coil-helix transition followed by aggregation of helices. Salts reduce electrostatic repulsions between chains and promote aggregation. Multivalent ions can act by crosslinking chains. Low acyl gellan gels are thermoreversible at low salt concentrations but non-thermoreversible at higher salt contents (b 100mM) particularly in the presence of divalent cations.
Methyl cellulose and hydroxypropylmethyl cellulose
Gels formed on heating. Molecules associate on heating due to hydrophobic interaction of
methyl groups.
Xanthan gum and locust bean gum or konjac mannan
Gels formed on cooling mixtures. Xanthan and polymannan chains associate following the xanthan coil-helix transition. For locust bean gum the galactose deficient regions are involved in the association.

source: hydrocolloids

INS numbers for hydrocolloids

           Polysaccharide                INS                     number Function
Alginic acid                      400      Thickening agent, stabiliser
Sodium alginate               401      Thickening agent, stabiliser, gelling agent
Potassium alginate           402      Thickening agent, stabiliser
Ammonium alginate         403      Thickening agent, stabiliser
Calcium alginate              404      Thickening agent, stabiliser, gelling agent,
                                                       antifoaming agent
Propylene glycol alginate         405      Thickener, emulsifier, stabiliser
(propane-1,2-diol alginate)
Agar                                          406      Thickener, stabiliser, gelling agent
Carrageenan (including            407      Thickener, gelling agent, stabiliser,
furcelleran)                                             emulsifier
Processed Euchema Seaweed   407a     Thickener, stabiliser
Bakers yeast glycan                  408      Thickener, gelling agent, stabiliser
Arabinogalactan                       409      Thickener, gelling agent, stabiliser
Locust bean gum                      410      Thickener, gelling agent
Oat gum                                    411      Thickener, stabiliser
Guar gum                                 412      Thickener, stabiliser and emulsifier
Tragacanth gum                      413      Emulsifier, stabiliser, thickening agent
Gum arabic (Acacia gum)       414      Emulsifier, stabiliser, thickener
Xanthan gum                           415      Thickener, stabiliser, emulsifier, foaming
Karaya gum                             416      Emulsifier, stabiliser and thickening agent
Tara gum                                 417      Thickener, stabiliser
Gellan gum                              418      Thickener, gelling agent and stabiliser
Gum ghatti                              419      Thickener, stabiliser, emulsifier
Curdlan gum                           424      Thickener, stabiliser
Konjac flour                            425      Thickener
Soybean hemicellulose            426      Emulsifier, thickener, stabiliser, anticaking
Pectin                                      440      Thickener, stabiliser, gelling agent,                                                                    emulsifier
Cellulose                                 460      Emulsifier, anticaking agent, texturiser,
                                                           dispersing agent
Microcrystalline cellulose       460 (i)   Emulsifier, anticaking agent, texturiser,
                                                         dispersing agent
Powdered cellulose               460(ii)   Anticaking agent, emulsifier, stabiliser and
                                                                 dispersing agent
Methyl cellulose                    461      Thickener, emulsifier, stabiliser
Ethyl cellulose                      462      Binder, filler
Hydroxypropyl cellulose      463      Thickener, emulsifier stabiliser
Hydroxypropyl methyl cellulose      464      Thickener, emulsifier stabiliser
Methyl ethyl cellulose          465      Thickener, emulsifier, stabiliser, foaming
Sodium carboxymethyl cellulose    466      Thickener, stabiliser, emulsifier
Ethyl hydroxyethyl cellulose           467      Thickener, stabiliser, emulsifier
Cross-linked sodium                        468      Stabiliser, binder
carboxymethyl cellulose
Sodium carboxymethyl                    469      Thickener, stabiliser
cellulose, enzymatically

INS numbers for modified starches

Modified starch*                 INS number
Dextrin (roasted starch)            1400
Acid treated starch                    1401
Alkali treated starch                  1402
Bleached starch                         1403
Oxidised starch                     1   404
Monostarch phosphate              1410
Distarch phosphate                    1412
Phosphated distarch                  1413
Acetylated starch                       1414
Starch acetate                            1420
Acetylated distarch adipate        1422
Hydroxypropyl starch                 1440
Hydroxypropyl distarch phosphate    1442
Starch sodium octenyl succinate     1450
Starch, enzyme treated              1405

Wednesday, June 23, 2010

guar specification and guar gum gum packing

Guar Gum Powder

Product Specification | Specialization | Packing
Guar Gum Powder
Botanical Name : Cyamopsis tetragonolobus, L
Family : Leguminosae
Part Used : Seeds
Vernacular Name : Guar
Imco Code : Harmless
EINECS No : 232-536-8
BTN : 1302 3290
CAS No : 9000-30-0
EEC No : E-412
During last decade Guar has immerged as an important industrial raw material and Produced by man for thousands of years. India has been the single largest producer and exporter of Guar gum accounting for more than 80 percent of the global output and trade.
Guar has now assumed a larger role among the domesticated plants due to its unique functional properties.
India Ranks First in the production of guar which is grown in the North Western part of the Country Which mainly includes the states of Rajasthan, Gujarat, Haryana and Punjab. Other main countries are Pakistan, U.S.A and Brazil.
The by product of Guar Gum industry consisting of the outer seed coat and germ material is called guar meal. The Guar meal after gum Extraction is a potential source of protein and contains about 42% crude protein which is one and a half times more than the level of protein in guar seed. The protein content in guar meal is well comparable with that of oil cakes. It is used as a feed for live stock including poultry. Guar meal contains two deleterious factors i.e. residual guar gum and trypsin inhibitor, Toasting of Guar Gum improves its nutritive value in chicks. Toasted guar Meal can be used in limited quantity i.e. Up to 10% in Poultry diet. However it can replace groundnut cake by almost 100% in animal feeds.
Guar Gum (Galactomanan) is a high molecular weight carbohydrate polymer made up of a large number of mannose and galactose unit linked together. The crude Guar Gum is a grayish white powder 90% of which dissolves in water. It is non ionic polysaccharide based on the milled endosperm of the guar bean whose average composition is :
Hydrocolloid    : 23%
Fats                : 40%
Proteins          : 34%
Guar Gum Galactomanan
The most important property of the Guar is its ability to hydrate rapidly in cold water to attain a very high viscosity at relatively low concentrations. Its specific colloidal nature gives the solution an excellent thickening power which is 6to10 timnes thicker than that obtained from starch . It is stable over a wide range of PH and it also improves the flowability and pumpability of the fluid. It is a superior friction loss reducing agent.
Product Specifications
Colour Appearance : Off White
Moisture : 10 - 12%
RIA : 2 - 2.5%
Protein : 4 - 4.5%
Ash : 1% Max
Gum Content : 80 - 85%
PH : 6 - 7
Heavy Metals : Less than 20 ppm.
Arsenic : 3 ppm
Lead : Less than 5 ppm
Viscosity(Cold) : ( 1% Sol. Brookf. Visc.RVT Mod.
  At 25oC Spi. No. 3/4, 20 rpm
  2 hrs and 24 hrs. 2 Hrs. 3500 - 4000 4500 -   5000
  24 Hrs. 4000 - 4500 5000 - 6500
TPC : Less than 10,000/gm. Less than 5000/gm.
Yeast Mold : 300/gm 200/gm
Salmonella : Ab. Ab.
E.Coli : Ab. Ab.
Streptococcus : Ab. Ab.
Pseudomonas : Ab. Ab.
Passing : 100 Mesh. 95 - 98%
  200 Mesh. 95 - 98%
  300 Mesh. 90 - 99%
Note : Above Specifications are In General. Material could be supplied according to the Buyer’s Specific Requirements.

Our Specialization In Guar Gum

 Carboxy-methylated Guar Gum, Hydroxy-Propylated and Ethylated Guar Gum, Oxidised and Cationic Guar Gum are new Developments in the Industry.
Packing and storage: Packing will be carried out in 25 Kgs. HDPE Laminated paper bags with Poly Ethylene liners inside.
Shelf Life: Min One year from the date of production provided Stored in a cool and Dry Place.

Sunday, June 20, 2010

Gomme de Guar E 412

Nature du produit : légumineuse (Cyamopsis tetragonolobus)
Propriétés :le Guar est issu d'une légumineuse annuelle et se présente comme une farine de graine apportant un pouvoir épaississant à froid de texture courte, assez neutre au goût qui peut être mélangé à de nombreux ingrédients comme liant basse calorie. Le Guar est employé dans tous les usages réclamant un épaississant neutre : il apporte viscosité et améliore rétention en eau des recettes. C'est un produit très visqueux à de très faibles concentrations. De faible prix et très disponible, il fait l'objet de nombreuses transformations chimiques qui permettent d'étendre son usage à des applications non alimentaires comme les peintures ou les gels cosmétiques. Le Guar a le statut de fibre végétale soluble acalorique. Il est très neutre et ne développe pas de gels avec le Xanthane ni le Carraghénane comme d'autres molécules galactomannanes issues de la même famille botanique (Tara, Caroube, Cassia). Modifié de façon à réduire sa viscosité, il peut servir à remplacer des molécules comme les sucres ou les amidons.
Le Guar :
- Apporte de la viscosité à faible température (moins que tara, et caroube ou carraghénanes)
- Améliore la rétention d'eau des aliments (surtout guar modifié)
- Est facile d'usage : même proportion pour toutes les recettes, insensible au pH et à la présence de différents sels.
- Est insensible aux enzymes protéolytiques
- Est peu réactif avec d'autres molécules et peu à la température (ne change pas de propriétés)
- A une faible synergie avec le Xanthane sans toutefois donner un gel à température ambiante.
- Est économique car s'utilise à petite dose
Emploi : le Guar se dissout facilement et n'apporte que peu de goût et pas d'odeur. En grandes quantités il a une perception farineuse, collante. Souvent son taux d'usage ne dépasse pas 1%. Il est employé partout dans toutes sortes de recettes car sans interaction avec les autres additifs. En général, il sert surtout pour épaissir mais aussi dans les glaces et les produits surgelés pour limiter la formation de gros cristaux. En boulangerie le Guar donne du moelleux car il freine la levée et réduit les pertes d'eau de la pâte et freine le rancissement de l'amidon.
Préparation : Le Guar est une poudre blanche cassée, pratiquement inodore et assez farineuse.
- La mélanger avec 3 à 5 fois son poids en sucre (glucose, maltose ou saccharose) ou un autre ingrédient facile à disperser et plus abondant (farines, amidons).
- Le produit s'hydrate à froid mais il vaut mieux de la chaleur et un bon mixage.
- Il est synergique avec le Xanthane et constitue le produit le plus courant pour apporter de la viscosité. Il ne donne pas toute sa viscosité immédiatement et il faut préférer une qualité plus grossière pour limiter la viscosité immédiate mais faciliter la mise en solution.


Tuesday, June 15, 2010

guar gum total.

I. History:

Guar, or clusterbean, (Cyamopsis tetragonoloba (L.) Taub) is a drought-tolerant annual legume that was introduced into the United States from India in 1903. Commercial production of guar in the United States began in the early 1950s and has been concentrated in northern Texas and southwestern Oklahoma. The major world suppliers are India, Pakistan and the United States, with smaller acreages in Australia and Africa. In the early 1980s, Texas growers were planting about 100,000 acres annually. They harvested about half of the planted acreage and plowed the rest under as green manure.

Unlike the seeds of other legumes, the guar bean has a large endosperm. This spherical-shaped endosperm contains significant amounts of galactomannan gum (19 to 43% of the whole seed), which forms a viscous gel in cold water. Guar gum is the primary marketable product of the plant. India and Pakistan export much of their guar crop to the United States and other countries in the form of partially processed endosperm material. World demand for guar has increased in recent years, leading to crop introductions in several countries.

Like other legumes, guar is an excellent soil-building crop with respect to available nitrogen. Root nodules contain nitrogen-fixing bacteria, and crop residues, when plowed under, improve yields of succeeding crops.

II. Uses:

In Asia, guar beans are used as a vegetable for human consumption, and the crop is also grown for cattle feed and as a green manure crop. In the United States, highly refined guar gum is used as a stiffener in soft ice cream, a stabilizer for cheeses, instant puddings and whipped cream substitutes, and as a meat binder. Most of the crop in the United States, however, is grown for a lower grade of guar gum, which is used in cloth and paper manufacture, oil well drilling muds, explosives, ore flotation, and a host of other industrial applications.

Guar gum consists of long branching polymers of mannose and galactose in a 2:1 ratio. After extraction of the gum, guar meal contains approximately 35% protein, which is about 95% digestible. The seed protein is low in methionine, like most legumes. Enough gum remains in the meal to make it an excellent feed pelleting material. Toasting improves its palatability to livestock and helps remove a trypsin inhibitor for non-ruminants.

III. Growth Habits:

Guar is an upright, coarse-growing summer annual legume known for its drought resistance. Its deep tap roots reach moisture deep below the soil surface. Most of the improved varieties of guar have glabrous (smooth, not hairy) leaves, stems and pods. Plants have single stems, fine branching or basal branching (depending on the variety) and grow to be 18 to 40 in. tall. Racemes are distributed on the main stem and lateral branches. Pods are generally 1 1/2 to 4 in. long and contain 5 to 12 seeds each. Seeds vary from dull-white to pink to light gray or black and range from 900 to 1,600 seeds/oz.

IV. Environment Requirements:

A. Climate:

Guar tolerates high temperatures and dry conditions and is adapted to arid and semi-arid climates. Optimum temperature for root development is 77 to 95°F. When moisture is limited, the plant stops growing but doesn't die. While intermittent growth helps the plant survive drought, it also delays maturity. Growing season ranges from 60-90 days (determinate varieties) to 120-150 days (indeterminate varieties). Guar responds to irrigation during dry periods. It is grown without irrigation in areas with 10 to 40 in. of annual rainfall. Excessive rain or humidity after maturity causes the beans to turn black and shrivel, reducing their quality and marketability. While profitable seed production in southern U.S. areas of high rainfall and humidity is likely to be limited, guar can be successfully grown as a green manure crop under these conditions. Guar varieties that require a particular daylength to flower or day-neutral have been described. Considering these high soil temperatures and long growing season, successful guar production in Wisconsin and Minnesota is very unlikely.

B. Soil:

Guar grows well under a wide range of soil conditions. It performs best on fertile, medium-textured and sandy loam soils with good structure and well-drained subsoils. Guar is susceptible to waterlogging. Guar is considered to be tolerant of both soil salinity and alkalinity.

Guar is an excellent soil-improving crop and fits well in a crop-rotation program with grain sorghum, small grains or vegetables. In Australia, guar was found to add 196 lb N/acre to the soil-plant system over three years. Increased yields can be expected from crops following guar because of increased soil nitrogen reserves. When used in rotation with cotton in Texas, researchers measured a 15% yield increase in cotton.

C. Seed Preparation and Germination:

Select seed that is uniform in color and size and is free from other crop and weed seed. New guar varieties have been released that have some resistance to diseases that once devastated fields of the crop. To prevent disease problems, select certified seed that does not contain seed of older varieties with less disease resistance.

Seed should be inoculated just before planting with a special guar inoculant or the cowpea (Group "E") inoculant. Exposure of inoculum to sunlight, heat and drying before planting can impair the effectiveness of the nitrogen-fixing bacteria. Seed should be planted in moist soil within 2 hours after inoculation. Fungicidal seed treatments may inhibit inoculation.

V. Cultural Practices:

A. Seedbed Preparation:

The seedbed should be firm and weed-free. Soil in the row should be ridged slightly to facilitate harvest of low-set beans.

B. Seeding Date:

Guar should be planted when soil temperature is above 70°F; the optimum soil temperature for germination is 86°F. A warm seedbed, adequate soil moisture and warm growing weather are essential for establishment of a stand. In Texas, June plantings of guar produce more reproductive buds than July plantings, resulting in substantially higher yields. Thus, production of this crop in the Upper Midwest is unlikely.

C. Method and Rate of Seeding:

1. Method of Planting: Guar is usually planted in 36 to 40 in. rows with a row crop planter. However, it can be broadcast seeded or planted in narrower rows with a grain drill if moisture is adequate. A planting depth of 1 to 1 1/2 in. is usually recommended. If guar seed is crushed, gumming or clogging of equipment may occur. To prevent clogging, holes on the bottom sides of the plates should be straight, rather than beveled or tapered. Adding graphite or a dry detergent to the seed box and reducing seed weight on the plates by filling the planter box only about one-third full may also help prevent gumming during planting.

2. Rate of Planting: Although some studies have found little effect on yield when seeding rates ranged from 5 to 44 lb seed/acre, other researchers have indicated an optimum seeding rate of 5 to 9 viable seeds/ft of row (30 in. rows). Current Texas recommendations are 5 lb/acre for 30 in. rows and 12 lb/acre for broadcast. Broadcasting should be practiced only where moisture is sufficient to support the higher plant population.

D. Fertility and Lime Requirements:

Nitrogen is not thought to be limiting in guar when the plants are well nodulated. Like most legumes, guar usually requires application of a rather high level of phosphorus (20 to 30 lb of P2O5/acre) and medium levels of potash (40 to 50 lb of K2O/acre). For highest yield, fertilize according to soil test results. Apply fertilizer below the seed before planting or to the side and below the seed at planting. Sulfur fertilizers have been found to affect guar on some soils, and zinc deficiency is a common problem in India.

Moderately alkaline soils are considered desirable for guar crop production (pH 7.0 to 8.0).

E. Variety Selection:

There have been notable improvements in guar varieties developed in the last 30 years. The newer cultivars are much more disease resistant with higher yields. Pod set in improved varieties is higher, and pods are well distributed on the main stem and branches, increasing harvest efficiency. The multiple branching of these newer cultivars also produces more pods.

Only the earliest-maturing varieties are recommended for production in Wisconsin and Minnesota.

Brooks, released in 1964, was the first improved variety, replacing Texsel and Groehler. Brooks has been grown on most of the guar acreage since 1966, but is rapidly being replaced by two newer releases, Kinman and Esser. Brooks is high-yielding and resistant to the major guar diseases, Alternaria leaf spot and bacterial blight. It is medium to late in maturity. Plants have a fine-branching growth habit and small racemes of medium-sized pods. Leaves and stem are glabrous. The seed is of medium size.

Hall is a slightly later-maturing variety than Brooks, and therefore not recommended for production in the Upper Midwest. It is resistant to bacterial blight and Alternaria leaf spot. Plants are relatively tall, coarse, finely branched, and produce small racemes of medium-sized pods. Leaves and stems are glabrous. This variety is best adapted to heavier soil types and higher elevations.

Mills is an early-maturing variety which also is resistant to bacterial blight and Alternaria leaf spot. Plants are short and finely branched and produce small racemes with relatively large pods. Leaves and stems are pubescent (hairy). Seeds are larger than those of Brooks and Hall. In dry seasons, Mills does not grow tall enough for efficient harvest. Yields are generally lower than those of Brooks and Hall.

Kinman, released by the Texas Agricultural Experiment Station, the USDA-ARS and the Oklahoma Agricultural Experiment Station in 1975, is derived from Brooks and Mills. Kinman is about 7 days earlier in maturity than Hall and of the same maturity as Brooks. It is highly resistant to bacterial leaf blight and Alternaria leaf spot. Kinman is slightly taller and coarser-stemmed than Brooks, but less so than Hall. It is fine branched and produces small-to-medium sized racemes. Seed pods are medium in length and generally contain from 7 to 9 seeds each. Seed of Kinman is slightly larger than Brooks. In 41 yield trials at eight locations in Texas and Oklahoma from 1971 to 1976, Kinman produced 17% more seed than Brooks.

Esser, released with Kinman in 1975, is a selection from progeny of the same Brooks × Mills cross. It is medium to late in maturity and therefore is probably not a good cultivar for Wisconsin and Minnesota. It has high resistance to Alternaria leaf spot and bacterial leaf blight. Esser has shown superior disease tolerance to Brooks and Kinman under severe bacterial blight conditions. Esser plants have Brooks' fine branching growth habit, but Esser has stronger main stems and fewer lateral branches. Esser produces small racemes with medium-sized pods.

Lewis, released by the Texas Agricultural Station and the USDA- ARS in 1986, is a selection from a cross of a glabrous parent with a pubescent (hairy) parent. Lewis is a medium-to-late maturing variety that is highly resistant to Alternaria leaf spot and bacterial leaf blight. Leaves, stems and pods are glabrous. Plants have a basal branching growth habit. The main stem and the basal branches possess short internodes with racemes initiated at each node over the entire plant. Plants are of average height, and racemes and pods are of medium length. Pods generally contain 5 to 9 seeds of average size. In 10 yield tests at five Texas locations during 1980-1983, Lewis produced mean seed yields approximately 25% higher than Kinman and 21% higher than Esser (Table 1).

Table 1. Yields of five guar varieties in Texas from 1980 to 1983.























Iowa Park



















Corpus Christi





































1Test received supplemental irrigation.
2Disease was present in the test.
Source: Stafford, R.E. 1986. Lewis: A New Guar Variety. Texas Agricultural Experiment Station Bulletin L-2177, February 1986. Texas A&M University System, College Station, Texas.

F. Weed Control:

Young guar plants grow slowly and are particularly susceptible to weed problems. Weeds can reduce yields and create harvesting problems.

1. Mechanical control: Guar should not be seeded in fields heavily infested with Johnsongrass (Sorghum halepense) and other perennial weeds. Early preparation of land and mechanical cultivations during the growing season will help minimize weed problems. Covering the lower branches during cultivation may promote development of disease and increase harvest difficulties.

2. Chemical: Treflan (trifluralin) is registered for use on guar as a preplant incorporated treatment to control most annual grass and several annual broadleaf weeds. Follow label instructions carefully for different soil types.

G. Diseases and Their Control:

Selecting disease-resistant varieties and high-quality certified seed is the best defense against disease problems. There are two major diseases of guar worldwide:

1. Alternaria leaf or target spot (Alternaria cucumerina var. cyamopsidis): This fungal disease may become severe during periods of heavy dew and high humidity. It causes a brown target-like lesion on the leaf between bloom and pod set. As the disease progresses, lesions enlarge, join and cause leaf drop.

2. Bacterial blight (Xanthomonas cyamopsidis): This seed-borne disease can cause loss of plants from the seedling stage until maturity. Symptoms include large angular necrotic lesions at the tips of leaves, which cause defoliation and black streaking of the stems. This is potentially the greatest disease hazard to guar.

H. Insects and Other Predators and Their Control:

The guar midge (Contarinia texana) is the primary guar insect pest in the Southwest. Heavy midge infestations have caused up to 30% loss in seed production. Guar midge infestations are generally heavier in fields with sandy or sandy loam soils.

Damage to guar is caused by the larvae, which develop in the guar buds. Infested buds eventually dry up and fall from the plant. The adult female midge deposits her eggs in developing buds. After larvae complete their development, they drop from the buds to the ground to pupate. There are several generations each year.

Rainfall or sprinkler irrigation can reduce midge populations drastically. However, field inspection should continue because midge infestation problems may increase again as a result of improved growing conditions. Control midges while guar is producing buds -- primarily between 45 and 90 days after emergence.

Other guar insect pests include the gall midge (Asphondylia sp.), three-cornered alfalfa hoppers, pea aphids, white grubs, thrips, and whiteflies. Storage pests have not been a problem with guar.

I. Harvesting:

Since guar beans generally do not shatter, the crop can be direct-combined as soon after maturity as possible. Harvest does not generally take place until after frost in northern regions. At maturity, the seed pods are brown and dry, and seed moisture content is less than 14%. Gramoxone (paraquat) can be used as a harvest aid to speed up drying and to kill weeds prior to frost. Apply when pods are fully mature. Preharvest interval is 4 days. Do not graze treated areas or use the treated forage for animal feed.

Guar beans can be harvested with an ordinary grain combine. The cylinder should be slowed and the combine speed reduced to a rate that will permit proper threshing of the beans. A high fan speed can be used to clean out foreign material. Reel speed should be slightly greater than combine ground speed. Improper reel speed can shatter seed pods. Reels should be set just deep enough in the guar to control the stalks, and should be about 6 to 12 in. ahead of the cutterbar. Some operators replace the wooden reel bats with 1/2 in. steel rods to reduce shattering. When harvested for hay, guar leaves drop readily unless extreme care is taken during the curing process. For hay, the crop should be cut when the first lower pods turn brown.

Guar can be harvested for seed and then plowed under or used as a mulch. If seed is not harvested, guar used for green manure should be turned under when the lower pods begin to turn brown.

J. Drying, Storage and Seed Quality:

Following harvest, the seed is graded for size and cleaned to remove shrunken seed and crop residue. Little information is available on optimum storage conditions for guar, but this has not been identified as a problem in most production guides. Following cleaning, milling for gum extraction may proceed.

The principal factors that decrease seed quality in guar are seed blackening and the production of small and shrunken seed. White seed is preferred for many food applications, and black seed is often discounted. Darkening tends to follow patterns of increasing rainfall, especially when it occurs during the period of seed maturation.

Small seed contains less endosperm and therefore is less desirable for milling. Late flowering, diseases, insects and low moisture can cause small seed (preferred size is 4 mm).

VI. Yield Potential and Performance Results:

Production practices and rainfall during the growing season cause seed yields to vary from about 300 to 2,000 lb/acre. Yields of several varieties in Texas are shown in Table 1. Experimental plantings of guar at Rosemont, Minnesota, have resulted in plants that bloomed but produced very little seed.

VII. Economics of Production and Markets:

Income and production costs for guar vary from year to year and according to soil types. Production costs often vary by $20 to $40/acre between farms because of different fertilizer usage and other production practices.

Demand for guar is increasing because of the wide use of the gum in more products and efforts of dealers to obtain a larger percentage of the gum from domestic sources. Growth in the early 1980s was estimated at 10% annually. Grade factors considered by the purchaser are the moisture, foreign material and test weight. Identify a market and secure a contract, if possible, before growing guar for bean production.

The value of guar as a soil builder to increase yields of succeeding crops should not be overlooked when considering guar as an alternative crop.

VIII. Information Sources:

  • Guar: A Potential Industrial Crop for the Dry Tropics of Australia. 1982. K.J. Jackson, J.A. Doughton. J. of the Australia Inst. of Agric. Science.
  • Kinman and Esser - New Guar Varieties. 1975. Texas Agricultural Experiment Station Bulletin L-1356. Texas A&M University System, College Station, Texas.
  • Lewis - A New Guar Variety. 1986. R.E. Stafford. Texas Agricultural Experiment Station Bulletin L-2177. Texas A&M University System, College Station, Texas.
  • Keys to Profitable Guar Production. L.D. Tripp, D.A. Lovelace, E.P. Boring. Texas Agricultural Extension Service Bulletin B- 1399. Texas A&M University System, College Station, Texas.
  • Guar: Production, Nutrition and Industrial Use. 1979. R. Whistler, and T. Hymowitz. Purdue University Press, Lafayette, Indiana 47907.

References to pesticide products in this publication are for your convenience and are not an endorsement of one product over other similar products. You are responsible for using pesticides according to the manufacturer's current label directions. Follow directions exactly to protect people and the environment from pesticide exposure. Failure to do so violates the law.