briquetting plant embryo

briquette plants&free briquetting technical consultation and instruction

briquette plants&free briquetting technical consultation and instruction

Crusher is a machine used on the surface of the metal fracture or compressed into small bits and pieces of pieces or dense mass materials. The vertical complex crusher developed and designed by our team of highly qualified engineers is used to reduce the size of the coal, charcoal, coke, lime, stone and such kind of materials into smaller sizes, so they can be more easily disposed of or recycled, or to reduce the size of a solid mix of raw materials (as in rock ore), so that pieces of different composition can be differentiated.

Feeder is for storaging the crushed raw material like coal dust, charcoal dust, etc. It is just like the silo. After crushing, the material comes into the feeder temporarily which guarantees enough and adequate amount of material going into the mixer.

briquetting - an overview | sciencedirect topics

briquetting - an overview | sciencedirect topics

Briquetting is a way to make use of biomass residues that would otherwise go to waste, and replace the use of wood and charcoal (often produced unsustainably) as well as fossil fuels, thus cutting greenhouse gas emissions.

Briquetting is a compaction technology that has been around for many years. Fines are pushed into the nip of two counter-rotating wheels using a screw or gravity feeder. High hydraulic pressure is applied and the rotating wheels compress the feed between the pockets to form briquettes. Unlike pelletization, briquetting does not always require a binder, but generally some amount of molasses, starch, or tar pitch is used. A traditional application for briquetting is the agglomeration of coal.

Most applications of briquetting in the iron and steel industry involve waste materials, such as mill scale and process dusts, sludges, and filter cakes [27]. In the DR industry, a number of facilities briquette their hot DRI product to produce a higher-density product for safer shipping. This material is known as HBI (hot briquetted iron), as discussed in Section 1.2.3.

Briquetting machines, with dies and punches, driven by a single bullock, have been developed by the School of Applied Research in Maharashtra, India. They cost about US$ 2400 each. The machine is very sturdy but the problem is the limited maximum production 25 kg/hr and the price of the equipment.

The same school has also developed a briquetting machine with two plungers driven by a 3 horse powermotor. The maximum capacity is 100 kg/hr and the price about US$ 4000. However, the pressure on the briquettes is not very high and it is necessary either to use a binder or to handle the briquettes with great care.

GAKO-Spezialmaschenen in West Germany produces briquetting equipment that uses the piston extruder compacting method and produces good quality briquettes because of the high pressure although this results in higher prices and power consumption. A 150 kg/hr machine costs about US$ 12 900 and a 60 kg/hr machine about US$ 8800 and requires a power load of 8.5 kW.

T & P Intertrade Corporation Ltd in Thailand markets a press-screw system briquetter that heats the agro-waste before compression. This means that good briquettes can be produced without needing a binder and at lower pressure, resulting in cheaper equipment. Their Ecofumac has a capacity of about 150 kg/hr, needs a 15 hp motor and three 2000 watt heaters and costs about US$ 5850. The grinder needs a 5 hp motor. Unfortunately a lot of energy is used by the heaters and there have also been some problems with other components.

It can be seen, therefore, that even if equipment does exist, the problems are not totally solved. Either equipment is too expensive with little capacity and too high an energy use, or poor quality briquettes result. There is still a need for a medium-size briquetting machine that is inexpensive, easy to operate, repairable using local tools and commonsense, energy efficient, reliable and which can handle different types of raw material. The advantage of medium-sized equipment is that capital investment is low and mechanized drying and special storage space is not required. In addition it would be practical for use in villages and in places with small wood industries or small agro-industries like groundnut oil mills, sugar mills, saw mills and paper mills. The briquettes could be used locally in bakeries, brickworks, potteries, curing houses, breweries, drieries or simply for cooking.

Briquetting is like pelletising a process in which the raw material is compressed under high pressure, which causes the lignin in the wood or biomass to be liberated so that it binds the material into a firm briquette.

The most appropriate water content in the raw material for briquetting varies and depends on the raw material. However, the normal water content is between 6% and 16%. If the water content is over 16% the quality of the briquettes will be reduced, or the process will not be possible.

There are hydraulic presses for small capacities from 50 to 400kg/hour. The raw material is fed into the press by a time-controlled dosing screw, which means that it is the volume of the raw material and not the weight, which is controlled. Briquettes have a fairly good uniform length (square briquettes) and they are mainly used by domestic consumers.

Mechanical presses are available with capacities from 200kg/hour up to 1800kg/hour. Briquettes from these presses are normally round and short and they are used in heating plants for larger industries and for district heating plants. A mechanical press is built like an eccentric press. A constantly rotating eccentric connected to a press piston presses the raw material through a conic nozzle. The required counter pressure can be adjusted only by using a nozzle with a different conicity. A mechanical press receives raw material from a speed-controlled dosing screw. The speed of the dosing screw determines the production rate of the press. A change in the specific gravity of the raw material will change the hardness of the briquettes. A mechanical briquetting press will produce a long length of material a briquette string which, however, breaks into random lengths depending on the binding capacity of the raw material. A saw or cutter is used to cut the briquette string into briquettes of uniform length.

The briquette string pushed out of the press is very hot because of the friction in the nozzle. The quality of the briquettes depends mainly on the cooling and transport line mounted on the press. A cooling/transport line of at least 15m is recommended for wood briquettes. The longer the time a briquette remains in the cooling line the harder it will become. Cooling lines up to 50m long are common.

Biomass briquetting technology can compress some biomass raw materials, such as wood shavings, sawdust, crop straw, and other solid waste biomass fuel through pressurizing and heating. It is conducive to the transportation, storage and combustion and can largely improve the efficiency of combustion and fuel utilization. At present, there are three main types of solid shaping, including screw extrusion, piston punch, and roller forming.

Thermochemical conversion involves biomass structure degradation with oxygenic or anoxygenic atmosphere at high temperature [100]. It includes three kinds of technology, namely biomass gasification, biomass pyrolysis, and direct liquefaction.

Biomass gasification is a chemical reaction process that reacts with gasifying agent (air, oxygen, and water) at high temperatures in gasifiers. The main problem of biomass gasification technology is that the tar obtained in the gasification of gas is difficult to purify, which has become the main factor restricting the biomass gasification technology.

Pyrolysis is a thermal process in which the organic polymer molecules in the biomass are quickly broken into short chain molecules, coke, bio-oil and noncondensable gas in the absence of oxygen or a small amount of oxygen under high temperatures. Biomass liquid fuel could provide an alternative to petroleum up to a certain extent. After some modification, industrial oil fired boilers and internal combustion engines can use bio-oil as fuel directly.

Burning biomass to obtain heat energy, as a direct utilization mode, has been more and more widely employed based on the mature experiences during development of fossil fuel power plants. When biomass is used as the boiler fuel, its thermal efficiency is close to the level of fossil fuels. Compared with fossil fuels, for example, coal, biomass fuel contains more hydrogen element, is more volatile, and has less carbon and sulfur content.

Bioconversion technology of biomass refers to the process by which microorganisms produce high-grade energy through biochemical action with agricultural and forestry wastes. Anaerobic fermentation and ethanol fermentation are the two main conversion types. With the help of anaerobic bacteria, organic matter can be converted to combustible gas, for example, methane under a certain temperature, humidity, pH, and anoxygenic conditions. The ethanol is produced by microzyme with the carbohydrate hydrolyzed by enzymes.

Renewed interest in briquetting coal has arisen because of (i) the increasing amounts of fine coal being generated in mining and preparation which are stockpiled or disposed of in tailings dams and lead to uneconomic land use and environmental problems; (ii) the need for easily handled and convenient coal products; and (iii) the demand for smokeless solid fuels.

Briquette quality depends on composition (type of coal and binder), particle sizes and processing conditions. In this study various data are presented on the influences of such factors on mechanical strength and water resistance of briquettes formed from high rank coals using a molasses/lime binder alone and also including bagasse. These data relate to Hardgrove grindability index (HGI), coal size, moisture and curing time.

White Energy developed the BCB technology at pilot scale in Australia, after initial work by CSIRO. In partnership with Bayan Group, White Energy formed PT Kaltim Supa Coal, and constructed a commercial scale 1 Mtpa plant at Tabang in East Kalimantan. The BCB process takes 4200 kcal/kg GAR feed and produces a 6100 GAR product. Its difference from Kobelcos UBC process is that BCB does not use any binder to reconstitute the dried product.

This project has been terminated due to commercial differences between the partners. The financial model used a sub-20 coal price delivered from mine mouth to plant. Bayan Group changed the price to follow the Indonesian Reference Price which more than doubles the feedstock cost. The parties are in negotiations to settle the dispute (White Energy, 2011).

Generally, briquette manufacture (briquetting) involves the collection of combustible materials that are not usable as such because of their low density, and compressing them into a solid fuel product of any convenient shape that can be burned like wood or charcoal. Thus the material is compressed to form a product of higher bulk density, lower moisture content, and uniform size, shape, and material properties. Briquettes are easier to package and store, cheaper to transport, more convenient to use, and their burning characteristics are better than those of the original organic waste material.

The raw material of a briquette must bind during compression; otherwise, when the briquette is removed from the mold, it will crumble. Improved cohesion can be obtained with a binder but also without, since under high temperature and pressure, some materials such as wood bind naturally. A binder must not cause smoke or gummy deposits, while the creation of excess dust must also be avoided. Two different sorts of binders may be employed. Combustible binders are prepared from natural or synthetic resins, animal manure or treated, dewatered sewage sludge. Noncombustible binders include clay, cement, and other adhesive minerals. Although combustible binders are preferable, noncombustible binders may be suitable if used in sufficiently low concentrations. For example, if organic waste is mixed with too much clay, the briquettes will not easily ignite or burn uniformly. Suitable binders include starch (5%10% w/w) or molasses (15%25% w/w) although their use can prove expensive. It is important to identify additional, inexpensive materials to serve as briquette binders in Kenya and their optimum concentrations. The exact method of preparation depends upon the material being briquetted as illustrated in the following three cases of compressing sugar bagasse, sawdust, and urban waste into cooking briquettes.

Rural villages in developing countries are connected to the drinking water supply without a sewer system. Other places in urban and semi-urban communities have no sewage treatment networks. Instead under each dwelling there is a constructed septic tank where sewage is collected or connected directly to the nearest canal through a PVC pipe. Some dwellings pump their sewage from the septic tank to a sewer car once or twice a week and dump it elsewhere, usually at a remote location.

In general, a huge amount of sewage and solid waste, both municipal and agricultural are generated in these villages. Because of the lack of a sewer system and municipal solid waste collection system, sewage as well as garbage are discharged in the water canals. This and the burning of agricultural waste in the field cause soil, water, and air pollution as well as health problems. Some canals are used for irrigation, other canals are used as a source of water for drinking.

Rural communities have had agricultural traditions for thousands of years and future plans for expansion. In order to combine the old traditions with modern technologies to achieve sustainable development, waste should be treated as a byproduct. The main problems facing rural areas nowadays are agricultural wastes, sewage, and municipal solid waste. These represent a crisis for sustainable development in rural villages and to the national economy. However, few studies have been conducted on the utilization of agricultural waste for composting and/or animal fodder but none of them has been implemented in a sustainable form. This chapter combines all major sources of pollution/wastes generated in rural areas in one complex called an eco-rural park (ERP) or environmentally balanced rural waste complex (EBRWC) to produce fertilizer, energy, animal fodder, and other products according to market and need.

The idea of an integrated complex is to combine the above-mentioned technologies under one roof, a facility that will help utilize each agricultural waste with the most suitable technique that suits the characteristics and shape of the waste. The main point of this complex is the distribution of the wastes among the basic four techniques animal fodder, briquetting, biogas, and composting (ABBC) as this can vary from one village to another according to the need and market for the outputs. The complex is flexible and the amount of the outputs from soil conditioner, briquettes, and animal food can be controlled each year according to the resources and the need.

Based on the above criteria, an environmentally balanced rural waste complex (EBRWC) will combine all wastes generated in rural areas in one complex to produce valuable products such as briquettes, biogas, composting, animal fodder, and other recycling techniques for solid wastes, depending upon the availability of wastes and according to demand and need.

The flow diagram describing the flow of materials from waste to product is shown in Figure 7.2. First, the agricultural waste is collected, shredded, and stored to guarantee continuous supply of waste into the complex. Then according to the desired outputs the agricultural wastes are distributed among the basic four techniques. The biogas should be designed to produce enough electrical energy for the complex; the secondary output of biogas (slurry) is mixed with the composting pile to add some humidity and improve the quality of the compost. And finally briquettes, animal feed, and compost are main outputs of the complex.

The environmentally balanced rural waste complex (EBRWC) shown in Figure 7.3 can be defined as a selective collection of compatible activities located together in one area (complex) to minimize (or prevent) environmental impacts and treatment cost for sewage, municipal solid waste, and agricultural waste. A typical example of such a rural waste complex consists of several compatible techniques such as animal fodder, briquetting, anaerobic digestion (biogas), composting, and other recycling techniques for solid wastes located together within the rural waste complex. Thus, EBRWC is a self-sustained unit that draws all its inputs from within the rural wastes achieving zero waste and pollution. However, some emission might be released to the atmosphere, but this emission level would be significantly much less than the emission from the raw waste coming to the rural waste complex.

The core of EBRWC is material recovery through recycling. A typical rural waste complex would utilize all agricultural waste, sewage, and municipal solid waste as sources of energy, fertilizer, animal fodder, and other products depending on the constituent of municipal solid waste. In other words, all the unusable wastes will be used as a raw material for a valuable product according to demand and need within the rural waste complex. Thus a rural waste complex will consist of a number of such compatible activities, the waste of one being used as raw materials for the others generating no external waste from the complex. This technique will produce different products as well as keep the rural environment free of pollution from the agricultural waste, sewage, and solid waste. The main advantage of the complex is to help the national economy for sustainable development in rural areas.

A collection and transportation system is the most important component in the integrated complex of agricultural waste and sewage utilization. This is due to the uneven distribution of agricultural waste that depends on the harvesting season. This waste needs to be collected, shredded, and stored in the shortest period of time to avoid occupying agricultural lands, and the spread of disease and fire.

Sewage does not cause transportation problems as it is transported through underground pipes from the main sewage pipe of the village to the system. Sewage can also be transported by sewage car which is most common in rural areas since pipelines may prove expensive.

Household municipal solid waste represents a crisis for rural areas where people dump their waste in the water canals causing water pollution or burn it on the street causing air pollution. The household municipal solid waste consists of organic materials, paper and cardboard, plastic waste, tin cans, aluminum cans, textile, glass, and dust. The quantity changes from one rural community to another. It is very difficult to establish recycling facilities in rural areas where the quantities are small and change from one place to another. It is recommended to have a transfer station(s) located in each community to separate the wastes, and compact and transfer them to the nearest recycling center as explained in Chapter 5. The transfer station consists of a sorting conveyer belt that sorts all valuable wastes from the organic waste, which is then compacted by a hydraulic press. The collected organic waste can be mixed with other rural waste for composting or biogas as explained above.

The outputs of the EBRWC are valuable and needed goods. EBRWC is flexible and can be adjusted with proper calculations to suit every village; moreover inputs and outputs from the complex can be adjusted every year according to the main crops cultivated in the village, which usually varies from year to year. The key element to the success of this solution lies in the integration of these ABBC technologies to guarantee that each type of waste is most efficiently utilized.

The four corner stone technologies for agricultural waste are animal fodder, briquetting, biogas, and composting (ABBC technologies). These technologies can be developed based on demand and need. In principal three agricultural waste recycling techniques can be selected to be the most suitable for the developing communities. These are animal fodder and energy in a solid form (briquetting) or gaseous form (biogas) and composting for land reclamation. There are some other techniques, which might be suitable for different countries according to the needs such as gasification, fiber boards, pyrolysis, etc. These techniques might be integrated into a complex that combine them altogether to allow 100% recycling for the agricultural waste. Such a complex can be part of the infrastructure of every village or community. Not only does it allow to get rid of the harms of the current practice of agricultural waste, but also of great economical benefit.

The amount of agricultural waste varies from one country to another according to type of crops and farming land. These waste occupies the agricultural lands for days and weeks until the simple farmers get rid of these waste by either burning it in the fields or storing it in the roofs of their houses; the thing that affects the environment and allows fire villages and spread of diseases. The main crops responsible for most of these agricultural wastes are the rice, wheat, cotton, corn, etc. These crops were studied and three agricultural waste recycling techniques were set to be the most suitable for these crops. The first technology is animal fodder that allows the transformation of agricultural waste into animal food by increasing the digestibility and the nutritional value. The second technology is energy, which converts agricultural wastes into energy in a solid form (briquetting) or gaseous form (biogas). The briquetting technology that allows the transformation of agricultural waste into briquettes that can be used as useful fuel for local or industrial stoves. The biogas technology can combine both agricultural waste and municipal waste water (sewage) in producing biogas that can be used in generating electricity, as well as organic fertilizer. The last technology is composting, that uses aerobic fermentation methods to change agricultural waste or any organic waste into soil conditioner. The soil conditioner can be converted into organic fertilizer by adding natural rocks to control N: P: K ratio, as explained before. Agricultural waste varies in type, characteristics and shape, thus for each type of agricultural waste there is the most suitable technique as shown in Figure 13.28.

A complex combining these four techniques is very important to guarantee each waste has been most efficiently utilized in producing beneficial outputs like compost, animal food, briquettes and electricity. Having this complex will not only help the utilization of agricultural waste, it will help solving the sewage problem as well that face most of the developing countries, as a certain percentage of the sewage will be used in the biogas production and composting techniques to adjust carbon to nitrogen ratio. An efficient collection system should be well designed to collect the agricultural waste from the lands to the complex in the least time possible to avoid having these wastes occupying agricultural land. These wastes are to be shredded and stored in the complex to maintain continuous supply of agricultural waste to the system and in turns continuous outputs.

somatic embryogenesis: process and applications | plants

somatic embryogenesis: process and applications | plants

In this article we will discuss about: 1. Process of Somatic Embryogenesis 2. Embryo Maturation and Synchronisation 3. Cultural Conditions 4. Recurrent Embryogenesis and Mass Production 5. Applications.

After fertilization, zygote is transformed into adult status through a series of embryogenic processes. Despite the same genetic constituents, somatic cells on the other hand, do not reorient towards embryo production. However, isolated somatic cells under in vitro conditions have the potential to develop into embryo under the influence of growth factors.

Somatic cells are able to develop into whole plant through the stages of embryogenesis without gametic fusion. Therefore, somatic embyros are non-zygotic embryos originated from sporophytic cells. Somatic embryo production is either direct or indirect in vitro. Somatic embryos may be direct when embryonic cells develop directly from the explants cells or indirect when developed through the callus.

Plant cells undergoing somatic embryogenesis are either pro-embryonic determined cells (PEDC) or induced embryogenic determined cells (IEDC). There have been reports on the induction of somatic embryos frequently from various tissues like seedlings, shoot meristem, young inflorescence and zygotic embryos. In addition, other tissues such as root, nucellus has also yielded somatic embryos.

The favorable responses of a few of the above tissues actually contain proembryogenic determinant cells (PEDC) or these cells may require minor reprogramming to enter embryogenic state. The first report on the production of somatic embryos in carrot suspension cells was published by Steward and co-workers in 1958. Thereafter reports were flooded on the production of somatic embryos in plants.

Reprogramming of somatic cells and its entry into the embryogenic status requires extensive proliferation through unorganized callus cycle and exposure to high doses of synthetic auxin such as 2, 4-D or picloram. Somatic embryo induction can also be accomplished by plasmolysis of explant cells.

The significance of auxin for embryo induction status from vegetative cells and tissue was recognized as the prime controlling factor. This is based on a critical assessment in species like Daucus carota, Atropa belladona and Ranunculus sceleratus. Transformation of embyrogenic cells into the callus system due to the differentiation of single cell is followed by the appearance of dense cytoplasm, prominent nucleus and high profiles of organelles.

These groups of small densely packed cytoplasmic cells arise by internal division. These groups of cells constitute pro-embyros which can develop into globular embryos. The formation of a mature embyro and plantlet via heart and torpedo shaped stages may proceed undisturbed even when exogenous auxin remains present at lowest concentration in the later development.

The later process in the prevalent media condition however, may disturb further establishment of embryogenesis unless auxin is completely omitted. It was even evidenced that embryogenic process may be completely arrested during transition of embryo to plantlet. Therefore auxin is reduced or entirely withdrawn once such anomaly appears during culture.

In date palm tissue culture, liquid media enriched with low amount of plant growth regulator resulted in the differentiation of large number of somatic embryos. High concentration of auxin may not encourage embryo formation. Therefore, two distinct conclusions can be drawn by the role of auxin in entire embryogenic episode.

First, induction of cells with reprogrammed embryogenic competence under the influence of auxin. Second one is directing embryogenic cells to undergo complete development by withdrawing auxin from the media. Low level of endogenous auxin can equally determine embryo induction.

Auxin deprivation acts as a development switch from nonpolar embryogenic units to induce somatic embryogenesis in maize. This developmental switch is accompanied by cytoskeletal rearrangements in embryogenic cells. Whole somatic embryogenetic process may derail the establishment of polarity if exogenous auxin is supplied.

One of the negative factors implicated in somatic embryogenesis is the production of ethylene in presence of auxin for a considerable period of time in the culture media. Production of ethylene in turn elevates the activity of enzymes, probably, cellulase and pectinase which degrade pectin compounds and consequently disturb establishment of polarity by reducing cell to cell interaction and contact due to separation.

Role of 2, 4-D in particular, for the induction of somatic embryogenesis is exemplary. Literature survey has shown that this synthetic auxin is very often suitable in inducing somatic embryogenesis in most of the species. Another synthetic auxin NAA has been found to be suitable for somatic embryo induction.

However, the role of phytohormones in somatic embryo induction is highly a complex process and varies depending on plant species as well as its endogenous concentration. Under no circumstances, gibberellic acid is useful for somatic embryo induction. But its role has been implicated in the maturation of somatic embryos.

The embryogenic competent cells seem to have preference for high salt strength and specific nitrogen source. This was considered to be a second pre-requisite for somatic embryo induction after auxin. The reduced form of nitrogen, ammonia, provides triggering factors for embryogenesis.

Similarly, nitrogen in the form of casein hydrolysate can equally contribute in the stimulation of somatic embryos and has been critically assessed in carrot as a model plant. Presence of proline and serine, capable of stimulating somatic embryo induction was reported in carrot plant.

Addition of reduced nitrogen, ammonium ion (NH4+ salt) or amino acids into the media is conductive for embryogenesis after shifting callus from auxin to auxin free media. It is however, concentration of auxin and nitrogen rather than critical concentration of reduced nitrogen which is crucial in empowering embryogenesis.

High frequency of somatic embryogenesis was achieved in cucumber plant. Addition of diazuron and sucrose treatment (3-6%) exerted positive effect on the relative position of somatic embryo induction. Addition of copper sulphate in the media induces high frequency somatic embryo induction.

Similarly, thiadiazuron when supplemented in the medium induced shoot organogenesis at low concentration and somatic embryogenesis at high concentration. Enhanced somatic embryo production and maturation into normal plants in cotton was achieved when calli cultured on half strength MS media.

A thorough examination of the role of reduced nitrogen ammonia shows that embryo formation is promoted when as little as 0.1 mM ammonium chloride is supplied to nitrate media. Embryogenesis is promoted by 40 mM potassium nitrate and 30 mM ammonium chloride as optimum concentration.

Glutamine and alanine can serve as sole nitrogen source for the growth and embryo formation. Although nitrate is required for embryogenesis on several instances, ammonium alone can produce embryo in carrot suspension culture, provided pH of the medium containing 10mM ammonium chloride and 20 mM potassium chloride was controlled at pH 5.4.

Level of dissolved oxygen has some role to play in somatic embryogenesis at least in carrot plant where embryogenesis takes place only below critical level of dissolved oxygen (i.e., above 1.5 ppm). Higher level favors rhizogenesis. Addition of activated charcoal into the culture media can promote embryo induction by adsorbing inhibiting substances produced by tissue.

Studies on embryo germination process shows that embryo development completes without any anomalies in the absence of auxin in the media. However, any abnormalities due to endogenous hormones can be avoided by supplementing balanced concentrations of abscisic acid (ABA), zeatin, and GA3. Addition of charcoal may increase the maturation of somatic embryo.

Presence of charcoal in the media reduces the level of auxin like IAA due to its binding effect. Somatic embryo maturation can be enhanced by subjecting to osmotic desiccation. Sucrose is generally used at different concentrations to achieve embryonic growth and maturation. This is achieved by providing sucrose concentration between 4 and 6%.

In certain species, progressive increase in sucrose concentration upto 4% is required for maturation, which consequently produces vigorous plantlets. Similarly, imposition of temporary desiccation before embryo germination facilitates conversion to plantlets. Imposition of desiccation can be progressed by placing somatic embryos in empty petridish and incubated at desiccated condition for 2-3 weeks and some plants upto several weeks.

Somatic embryos, when shriveled to 50% of their original volume rapidly imbibe water when rehydrated by transfer to media. The whole exercise of desiccation in embryo is to influence metabolic process for germination. Somatic embryos when subjected to show desiccation, it stimulates the production of high frequency of shoot regeneration.

Imposition of desiccation improves conversion to plantlets several times the frequency of non-desiccated embryos. In Alfalfa culture, somatic embryos have been trained to withstand desiccation by treating them with ABA at the torpedo stage. ABA treatment can promote the development of cotyledons and block the production of embryo clusters.

High light intensity can influence the process of somatic embryogenesis. However, cultures were incubated under both light and dark periods. Early maturation takes place more predominantly under complete dark conditions.

Reports on the influence of temperature on somatic embryogenesis are scarce. In citrus nucellus culture, embryogenic potential drops when the temperature was reduced from 27C to 12C. Similarly, conditioning of somatic embryos by cold treatment can escape dormancy and facilitate development.

The primary somatic embryo when fails to undergo maturation may enter continuous successive cycles of embryos. Certain specific superficial cells of the hypocotyl or cotyledon exhibit this tendency in provoking successive cycles of embryos or in other words continuous production of supernumerary embryos from somatic embryos itself.

This phenomenon is also known as secondary embryogenesis, recurrent embryogenesis, repetitive or accessory embryogenesis (Fig. 8.1). Recurrent embryogenic cycle can be maintained in culture by the removal of growth regulators and cycles can be spontaneous as this was evidenced in Alfalfa (Medicago sativa).

Recurrent embryogenesis cycle can be made spontaneous by locking the development of somatic embryos particularly at proembryogenic status, beyond which they cannot proceed to develop. This can be accomplished by initial exposure to very high concentration of 2, 4-D upto 40 mg/L for brief period followed by exposure to a lowest concentration (3-5 mg/L).

This high concentration of auxin treatment may be involved in reprogramming of cells and reinduce embryogenic competence. Repetitive embryogenesis may be a serious problem during spontaneous cycles of somatic embryo production when germination and further development is required.

One of the most striking features of somatic embryogenesis is the successful crackdown on RNA expression in embryogenic and nonembryogenic tissues. Several striking similarities were cited in the gene products expressed in embryogenic and nonembryogenic cultures. The tissue culture conditions are typically defined as nonembryogenic. The pattern of gene expression between embryogenic and nonembryogenic systems exhibit least diversity about RNA expression profiles.

Limited number of changes has been recorded in protein expression pattern during somatic embryogenesis. Similarly, changes in mRNA populations take place during transition from nonembryogenic to various embryo stages. Removal of auxin from the media during embryo induction triggers new profiles of gene expression that are eventually coupled to observe morphogenetic events.

One of the most promising applications of somatic embryogenesis is large scale propagation of somatic embryos, which shows several advantages such as innumerable number of embryo production (60,000-70,000 embryos per litre of media), presence of both root and shoots meristems, easy to scale up and convert them into seedlings efficiently as far as commercial significance is considered. Somatic embryos are genetically well programmed to make a complete plant. Thus, unlike other micro-propagation systems, somatic embryogenesis avoids certain stages of micro-propagation particularly, the rooting stage.

Synthetic seeds or artificial seeds are the somatic embryos encapsulated by gel entrapment solution. Artificial seeds are generally produced in plant species which exhibit seed sterility and difficulty or slow phase of vegetative propagation.

This can be prepared by placing somatic embryos in alginate slurry (2%) as gel entrapment matrix and subsequently transferred to calcium chloride (100 mM) solution to form beads in which embryos get entrapped. Artificial seeds can be stored at 4C for a considerable period of time and used as efficient system for germplasm conservation. For regeneration, seeds can be placed in culture media or in sterile soil to facilitate germination and seedling development (Fig. 8.2).

Repetitive embryogenesis often provides innumerable number of somatic embryos, which in turn is useful in the mass production of plant propagules. Several embryo specific metabolites like seed storage proteins and lipids of industrial value can be recovered. Lack of seed tissue surrounding somatic embryos proves significant advantage for certain lipids such as -linolenic acid present at high level in Borage seeds.

This lipid is of high commercial significance in the treatment of atopic eczema. Surprisingly, somatic embryos as an analogue of zygotic embryo also synthesize the same amount of -linolenic acid. Similarly, jojoba plant contains high quality industrial lubricant in their seeds.

Somatic embryos obtained from zygotic embryos as the explant possesses waxes identical to that of zygotic embryos. In addition, novel metabolites can be produced in somatic embryos throughout the season.

Somatic embryos are an ideal system for gene transfer process. This particular approach can avoid protoplast mediated regeneration of transformed plants which generally requires additional care. Moreover, protoplast mediated regenerated plants can exhibit genetic variation. Since somatic embryos maintain genetic stability, regenerated plants are not susceptible for somaclonal variation.

Somatic embryos can be transformed by incubating them in Agrobacterium solution or subjected for particle bombardment. Embryo cloning by recurrent approach is well suited for direct gene transfer to the mass of somatic embryos. The stably transformed somatic embryos can be farther subjected for recurrent embryogenic cycle to procure millions of transgenic plants.

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what is briquetting plant and where to buy the best briquette machine? - ecostan

what is briquetting plant and where to buy the best briquette machine? - ecostan

If we are not wrong then you are here to know about briquetting plant, right? Obviously, thats why you are here. Dont worry here you will know all your answer about briquette plant. Briquetting plant is basically a technology which turns all kind of forestry, industrial and agricultural waste into solid fuel. Briquette machines turn the finished element into cylindrical logs with the help of high mechanical pressure this is done without any help of binder or chemical. You can establish your own briquette plant with the help of Ecostans briquette machine. Our machine is able to make quality briquettes without any chemical or binder. With the help of highly pressurized mechanical punch, it will reduce the size of raw material which is easy to transport and moreover this process will increase the calorific value.

Ecostan briquetting plant produces such briquetting machine which works on the principle of binder less technology. We have more than 22 years of experience in briquetting plant field. Before launching any machine we do a considerable R&D so at the end only fine and quality briquette plant is produced. Our machines are produced under the supervision of experienced engineers who keep an eagle eye on every minor detail with the help of hi-tech Japanese machines.

Furthermore, other vernacular names of briquette plant are screw briquetting machine, briquette press, screw briquetting, mud press, tuda machine, getting the machine, saw dust machine, jumbo machine, rice husk briquette machine and more. We prefer to call them PRIME 40, CLASSIC 60, STANDARD 70, BULL 80, SUPREME 90, and EVEREST 100.

These are also the models too which are able to produce 2500 KG/H, 2000 KG/H, 1500 KG/H, 1300 KG/H, 1000 KG/H, and 325 KG/H respectively. These machines need power requirements in between 89 HP to 18 HP. Hope you get your answer if still want to ask any question then feel free to ask in the comment section.

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