Crude glycerol from bio-diesel production as a processing aid for industrial explosives.
FIELD OF INVENTION
This invention relates to crude glycerol from bio-diesel production as a processing aid for industrial explosives.
BACKGROUND OF INVENTION
The water gel slurry and emulsion compositions are commercial explosives and are used for mining civil applications.
The slurry explosives, as such known in the art, comprise 38-80% oxidizer salts such as Ammonium Nitrate, Calcium Nitrate, sodium Nitrate, Potassium nitrate and Zinc Nitrate by weight of total composition of explosive slurry, 2-9% water miscible liquid/solid fuels such as glycols, alcohols, ethers and sugar: 0.3-1.8% thickeners like guar gum 7-9% sensitizer and other premixed solid fuels such as flaked and atomized aluminum powder, glisonite/battery pitch powder and other starchy materials and 0.25 to 1.5% cross linking and gassing agents like borax metallic antimonates, dichromates, chromates, azides, nitrites and other gas generating compounds in a manner so that oxygen balance of the system close to zero.
The process of preparing slurry explosives in the known art consist of making oxidizer salts' solution by dissolving Ammonium Nitrate(AN) along with Calcium Nitrate(CN), Sodium Nitrate(SN) and/or Potassium Nitrate(PN), Zinc Nitrate(ZN) and Thio Urea in water. To this solution finely powder gum/thickening agent and water miscible liquid and solid
"3-fuels are added to obtain the gummed oxidizer solution. Other premixed solid fuels are added to the gummed oxidizer solution along with the gassing and cross linking agents to obtain explosive slurry.
The oxidizer slats are dissolved in 12-19% water by weight to total weight of the explosive slurry in the following percentage ranges:

(Table Removed)
The sensitizers and other premixed solid fuels composition used for the preparation of the slurry explosive as such known in the art comprises following ingredients in the amount as mentioned against such ingredients.

(Table Removed)
There are some disadvantages associated with the slurry explosives known in the prior art and process for he manufacture thereof. One of
-4-the main disadvantages is that the explosive slurry has poor homogeneity causing poor combustion/detonation efficiency and therefore, leads to poor performance during detonation. Since the finely divided guar gum powder is added to the oxidizer solution the formation of gum agglomerates takes place due to the higher affinity of the guar gum towards water which leads to poor homogenization and poor quality of the final explosive product.
Another disadvantage is that the presence of gum agglomerates causes pumping problem during transfer of the solution to the mixing blender which affects its easy mixing with the premixed solid fuels.
Yet another disadvantage in the known art the presence of water in the dispersion media like MEG leads to instant hydration and caking of polymer dispersion system making it's pump ability/flow difficult.
OBJECTS OF INVENTION
The main object of the present invention is to propose a novel slurry explosive composition and a process for the preparation thereof.
Other object of this invention is to propose a water gel slurry explosive composition and the process of manufacture so as to enhance the homogenization of the ingredients of the explosive composition to obtain products of improved quality and performance.
Yet another object of this invention is to propose a water gel slurry explosive composition and process thereof so as to delay the hydration of guar gum in the oxidizer solution thereby allowing time for its proper and uniform distribution in the oxidizer solution which leads to one to one contact of oxidizer and fuel thereby complete combustion. -
STATEMENT OF INVENTION
This invention relates to a water gel slurry explosive composition comprising 76 to 88% oxidizer solution, 2.6 to 6.5% guar gum dispersion, 7.4 to 17.1% premixed solid fuels, 0.1 to 2% gassing and cross linking agents and the process for preparation thereof comprising, addition of guar gum dispersion to oxidizer solution at 55-60°Cunder agitation, addition of premixed solid fuels, and gassing and cross linking agents to the gummed solution and mixing wherein delayed hydration of guar gum favours homogeneous mixing and hinders guar gum agglomerates formation when mixed with oxidizer solution. Emulsion (water in oil) explosive composition comprising 79-94% matrix, 05-20% solid fuels, 0.1 to 2% gassing agent, wherein emulsion matrix, having 92.5 to 94% oxidizer solution, 6 to 7.5% fuel phase and the process for preparation thereof comprising, preparation of oxidizer solution at 70-75C under agitation, blending of oxidizer solution with 6 to 7.5% fuel phase in a specially designed blender to get the emulsion matrix, adding solid fuels and gassing agents and mixing to get the emulsion explosive, wherein better emulsification occurs due to the presence of surface active agents in the crude glycerol and increases the shelf life of the emulsion explosive product thereby giving better detonation.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Further objects and advantages of this invention will be more apparent from the ensuing description when read in conjunction with the accompanying drawings and wherein:
Fig. 1 shows Hydration of Guar Gum in Crude Glycerol and water. Fig. 2 shows: hydration of Guar Gum in Glycerol and water
Fig. 3 shows: illustrates study of phase separation in Emulsion after 24
hours.
Fig. 4 shows: comparison of onset of crystallization in Explosive
Emulsion products.
DETAILED DESCRIPTION OF THE INVENTION WITH REFERENCE TO THE ACCOMPANYING DRAWINGS
According to this invention there is provided a process for the preparation of water gel slurry explosive composition comprising 76 to 88% oxidizer solution, to that 2.6 to 6.5% guar gum dispersion is added to this gummed solution 7.4 to 17.1% premixed solid fuels are added with 0.1 to 2% gassing and cross linking agents to prepare the water gel slurry explosive composition.
In the present invention, the process for the preparation of a slurry explosive composition comprise in preparing an oxidizer solution having 31-71% Ammonium nitrate (AN), 14-38% Calcium Nitrate tetrahydrate (CN4), 2.5-16.5% Sodium Nitrate (SN) or Potassium Nitrate (PN), 0.5-2% Zinc nitrate (ZN) and (0.2-0.3%) Thi Urea (TU). The gum dispersion was added to the oxidizer solution to form homogeneous gummed oxidizer solution. The premixed solid fuels are then added to the gummed oxidizer solution in the presence of gassing and cross-linking agents in order to prepare a homogenized water gel slurry explosive composition.
In this invention the mixer of oxidizer salts solution is first prepared by mixing 31-71% Ammonium nitrate (AN), 14-38% Calcium Nitrate (CN), 2.5-16.5% Sodium Nitrate (SN) Potassium Nitrate (PN), 0.5-2% Zinc Nitrate (ZN) and (0.2-0.3%) Thi Urea (TU) in 14-20% water.

-!■-The gum dispersion was prepared by dispersing the guar gum in crude glycerol obtained from biodiesel production process was filtered using muslin cloth and neutralized using nitric acid is taken in a kettle (41-45%) and to that guar gum (5-10%) is added "under agitation. After complete dispersion of guar gum diesel (50-59%) is added.
The premixed solid fuel composition comprises all the components as such known in the art.
Example 1
The guar gum dispersion was prepared by dispersing five parts guar gum in forty one parts of crude glycerol at room temperature and to that fifty four parts diesel fuel was added. The oxidizer solution was prepared by dissolving 43-8 parts Ammonium Nitrate (AN), 38.72 parts Calcium Nitrate tetra hydrate (CN4), 5.78 parts Sodium Nitrate (SN), 1.7 parts Potassium Nitrate (PN), 0.5 parts Zinc Nitrate (ZN) and 0.21 parts of Thio Urea (TU) in 4.41 parts water at 55-60°C under agitation to get oxidizer solution. The guar gum continued for 1-2 hours for complete hydration of the guar gum to get the gummed oxidizer solution. This gummed oxidizer solution (88.6 parts) was mixed with 11.2 parts of solid premixed fuel comprising (66.36 parts) sulphur power, (33.64 parts) hydrating starchy materials and traces of cross linking agent Sodium dichromater (0.1 part) and gassing agent Sodium Nitrite (0.04 parts) at 55-60°C to get the slurry explosive. The explosive thus prepared was filled in 88 mm, 125 mm dia LDPE tubing to form slurry explosive cartridges. The product density was found to be 1.14 gm/cc which gave the velocity of detonation 4000mt/sec.
Example II
The guar gum dispersion was prepared by dispersing six parts guar gum in forty two parts of crude glycerol at room temperature and to that fifty two parts diesel fuel was added. The gummed oxidizer solution was prepared by the same process as described above in example -1 and (88.36 parts) thereof was mixed with 11.5 parts of solid premixed fuel comprising of Flacked /Atomized Aluminium powder (41.47 parts) Sulphur (17.66.parts), hydrating starchy materials (34.85 parts), Battery pitch (6.22 parts) and trace comprising cross linking agent Sodium dichromate (0.1 part) and gassing agent Sodium.Nitrite (0.04 parts) at 55-60°C to get the slurry explosive. The explosive so prepared was filled in 83mm, 125mm dia LDPE to be in the range of 1.2-1.14 gm/cc which gave the velocity of detonation 440mt/sec.
EMULSION EXPLOSIVE
The water in oil emulsion explosives, as such known'in the art, comprise 38-80% oxidizer salts such as Ammonium Nitrate, Calcium Nitrate, Sodium Nitrate, Potassium Nitrate and Zinc Nitrate by weight of total composition of emulsion explosive 0.6% liquid/solid fuels such as hydrocarbon oils and 0 to 5.5 percent of Aluminium powder, 0-20% prilled ammonium nitrate as sensitizers and 0.75-2.25% emulsifier and co-emulsifier like Sorbitan monooleate and 0.25 to 1.5% gassing agents like Sodium nitrite and other gas generating compounds in a manner so that oxygen balance of the system close to zero.
The process of preparing emulsion explosives in the known art are consists of making oxidizer salts solution by dissolving Ammonium Nitrate (AN) along with Calcium Nitrate (CN), Sodium Nitrate (SN) and/or Potassium Nitrate (PN), Zinc Nitrate (ZN) and Tho Urea (TU) in water.
This oxidizer solution is blended in a specially designed blender with fuel phase comprising of emulsifier, co-emulsifier and hydrocarbon oil to get the emulsion matrix which is then mixed with gassing agents to obtain explosive emulsion.
The oxidizer salts are dissolved in 14-20% water by weight of total weight of the explosive emulsion in the following percentage ranges:

(Table Removed)
The sensitizers and other solids fuel composition used for the preparation of the emulsion explosive as such known in the art comprises following ingredients in the amount as mentioned against such ingredients:

(Table Removed)
There are some disadvantages associated with the emulsion explosives known in the prior art and process for the manufacture thereof. One of the main disadvantages is that the explosive emulsion has poor self life causing breaking down of emulsion thereby poor combustion/detonation efficiency and therefore, leads to poor performance during detonation.
Another disadvantage is that the presently used emulsifiers for the preparation of water in oil emulsion explosive has low emulsion stability leading to the phase separation and breaking of emulsion. In explosive chemistry the closer the oxidizer and fuel, the better is the combustion and higher is the performance of the explosive.
Therefore the main objective of the present invention is to propose a novel emulsion explosive composition and a process for the preparation thereof in order to obviate the disadvantages associated with the prior art.
Another objective of the present invention is to propose emulsion explosive composition and the process of manufacture thereof so as to enhance emulsification and stability of emulsion explosive, to obtain products of improved quality and performance.
The crude glycerol due to presence of surface active components in trace amount assist in stabilizing w/o explosive emulsion compositions offering technical and economic advantages.
According to this invention there is provided an emulsion explosive composition and the process for the preparation thereof comprising 92.5 to 94% oxidizer solution, 6 to 7.5% fuel phase to get the emulsion matrix and to that 05 to 20% solid fuels and 0.1 to 2% gassing agents are added to get the emulsion explosive.
In the present invention, the process for the preparation of an emulsion explosive composition comprise in preparing an oxidizer solution having 31-71% Ammonium nitrate (AN), 14-21% Calcium Nitrate tetrahydrate (CN4), 2.5-16.5% Sodium Nitrate (SN) or Potassium Nitrate (PN) and 0.5-2% Zinc Nitrate (ZN) and (0.2-0.3) Tho Urea (TU) in 4-5% water.

The fuel phase was blended with the oxidizer solution in a specially designed blended with the oxidizer solution in a specially designed blended to form water in oil emulsion matrix. The solid fuels and sensitize were then mixed with the emulsion matrix in the presence of gassing agents in order to prepare water in oil emulsion explosive composition.
In this invention the oxidizer salts solution was first prepared by mixing 31-71% Ammonium nitrate (AN), 14-21% Calcium Nitrate tetrahydrate (CN4), 2.5-16.5% Sodium Nitrate (SN) or Potassium(PN) and 0.5-2% Zinc Nitrate (ZN) and (0.2-0.3) Tho Urea(TU) in 4-5% water.
The fuel phase was prepared by mixing Sorbitan mono oleate, diesel fuel and crude glycerol obtained from biodiesel production process. In this process (31-35%) crude glycerol obtained from biodiesel production process was.filtered using muslin cloth and neutralized using nitric acid was taken in a kettle and to that Sorbitan mono oleate (7.5-15%) and diesel (50-50%) was added under agitation. The presence of these surface active species provides synergistic advantage in terms of improved emulsification/homogenization, improved life and better detonation properties of the prepared composition.
Example -1
The fuel phase was prepared by mixing Sorbitan mono oleate, diesel fuel and crude glycerol obtained from biodiesel production process. In this process (35%) crude glycerol obtained from biodiesel production was filtered using muslin cloth and neutralized using nitric acid was taken in a kettle and to that Sorbitan mono oleate (15%) and diesel (50%) was added under agitation.
In this invention the oxidizer salts solution was first prepared by dissolving 61% Ammonium nitrate (AN), 17% Clacium Nitrate tetrahydrate (CN4), 5% Sodium Nitrate (SN), 2% Zinc Nitrate (ZN) and 0.21% Tho Urea (TU) in 14.79% water at 70-75°C under agitation to get oxidizer solution. The 6.75% fuel phase was blended at 70-75°C -with 93.25% oxidizer solution using a blender to get the emulsion matrix. This emulsion matrix (88.66 parts) was mixed with 10 parts of coated prilled Ammonium Nitrate, 1.3% Aluminium powder and gassing agent Sodium Nitrite (0.04 parts) to get the emulsion explosive. The explosive thus prepared was filled in 83mmm, 125mm dia LDPE tubing to form emulsion explosive cartridges. The product density was found to be 1.14 gm/cc which gave the velocity of detonation 4400mt/sec.
Example -11
The fuel phase was prepared by mixing Sorbitan mono oleate, diesel fuel and crude glycerol obtained from biodiesel production process. In this process (33%) filtered and neutralized crude glycerol obtained from biodiesel production process was taken in a kettle and to that Sorbitan mono oleate (15%) and diesel (52%) was added under agitation. In this invention the oxidizer salts solution was first prepared by dissolving 61% Ammonium nitrate (AN), 17% Calcium Nitrate tetrahydrate (CN4), 5% Potassium Nitrate (PN) and 2% Zinc Nitrate (ZN) in 15% water at 70-75°C under agitation to get oxidizer solution. The 6.75% fuel phase was blended at 70-75°C with 93.25% oxidizer solution using a blender to get the emulsion matrix. This emulsion matrix (87.66% parts) was mixed with 10 parts of coated prilled Ammonium Nitrate, 2.3% Aluminium powder and gassing agent Sodium Nitrate (0.04 parts) to get the emulsion explosive. The explosive thus prepared was filled in 83mm, 125mm dia LDPE tubing to form emulsion explosive cartridges. The
product density was found to be 1.12 gm/cc which gave the velocity of detonation 4500mt/sec.
HYDRATION OF GUAR GUM IN CRUDE GLYCEROL & WATER
Table: 1

(Table Removed)
Table 2
(Table Removed)
It is observed that the crude glycerol mixture shows higher water resistant and delayed hydration which is a prerequisite in explosive chemistry. This may be because of the presence of small amount of esters in the crude glycerol which form a temporary coating on the guar gum particles and subsequently on stirring it scratches permitting the water to hydrate the guar gum slowly. The delayed hydration favours better dispersion of guar gum and thereby better fuel and oxidizer contacts which gives higher energy to the industrial gel explosive product.
Emulsion Formation In the presence of CO-LSC and Crude glycerol from biodiesel
Production
The results indicate that the employment of crude glycerol as co-solvent/co-emulsifier in place of currently used system enhaces the emulsion phase formation by 11 percent and the oil phase separation is minimum i.e 06 percent only. This again indicates the improvement in the emulsion stability of emulsion prepared using crude glycerol.

(Table Removed)
(*)-Co-Emulsifier: CO-LSC, (**)-CO-Emulsifier: Crude Glycerol, (***)-Co-Emulsifier: Nil
Table 3 Emulsion Formation In the presence of CO-LSC and Crude Glycerol from biodiesel Production
Comparison of Onset of Crystallization
The growth of needle like white crystals are observed visually by the naked eyes after the breaking of emulsion i.e after the self life is over. The properties of emulsion explosive products using crude glycerol and the products presently in use are comparable. However on-set of crystallization, which is a strong indicator of enhanced emulsion stability has increased from 11 days to 15 days with the use of crude glycerol as co-emulsifer/co-solvent in the emulsion explosives products.
(a) Emulsion explosive prepared using (B) Emulsion explosive prepared using crude glycerol after (CO LSC) crystallized after 11 days 15 days.

We Claim
1. (A). A water gel slurry explosive composition comprising 76 to 88%
oxidizer solution, 2.6 to 6.5% guar gum dispersion, 7.4 to 17.1% premixed solid fuels, 0.1 to 2% gassing and cross linking agents and the process for preparation thereof comprising: -
i) addition of-guar gum dispersion to oxidizer solution at 55-60C under agitation.
ii) addition of premixed solid fuels and gassing and cross linking agents to the gummed solution and mixing wherein delayed hydration of guar gum favours homogeneous mixing and hinders guar gum agglomerates formation when mixed with oxidizer solution.
{B). Emulsion (water in oil) explosive composition comprising 79-94% matrix, 05-20% solid fuels, 0.1 to 2% gassing agent, wherein emulsion matrix, having 92.5 to 94% oxidizer solution, 6 to 7.5% fuel phase and the process for preparation thereof comprising: -
i) preparation of oxidizer solution at 70-75C under agitation
ii) blending of oxidizer solution with 6 to 7.5% fuel phase in a
specially designed blender to get the emulsion matrix iii) adding solid fuels and gassing agents and mixing to get the emulsion explosive, wherein better emulsification occurs due to the presence of surface active agents in the crude glycerol and increases the shelf life of the emulsion explosive product thereby giving better detonation.
2. A water gel slurry explosive composition as claimed in claim 1,
wherein said oxidizer salts solution comprises 31-71% Ammonium
nitrate (AN), 14-38% Calcium Nitrate (CN), 2.5-16.5% Sodium Nitrate
(SN), Potassium Nitrate (PN), 0.5-2% Zinc Nitrate (ZN) (0.2-0.3) % Thi
Urea(TU) and 14-20% water,
3. A water gel slurry explosive composition as claimed in claim 1, wherein said guar gum dispersion comprises (41-45%) crude glycerol (5-10%) guar gum and (50-59%) diesel.
4. An Emulsion explosive composition as claimed in claim 1, wherein said oxidizer salts solution comprises 31-71% Ammonium nitrate (AN), 14-21% Calcium Nitrate (CN), 2.5-16.5% Sodium Nitrate (SN) or Potassium Nitrate (PN) and 0.5-2% Zinc Nitrate (ZN) and Tho Urea (TU) in 14-20% water.
5. An emulsion composition as claimed in claim 1, wherein emulsion matrix comprises (31-35%) crude glycerol, (7.5-15%) Sorbitan mono oleate an (50-59%) diesel.