System Approach for Utilisation of Gypsum - A Mineral Resource

Code No:TMS149Price:Rs2300/-Category:Materials & Chemicals: Minerals

 

Summary  : India has huge reserves of natural gypsum of the order of 1120 million tonnes of which recoverable reserves are estimated at 237 million tonnes. Apart from this there is annual surplus production of gypsum of the order of 2 to 3 million tonnes from industrial and marine sources. Due to increased use of by-product gypsum, which is of higher purity than the natural gypsum, the natural gypsum is facing a competition from by-product gypsum. Consumption of natural gypsum is now confined to cement and Plaster of Paris. In order to facilitate and explore alternative uses of gypsum such as conditioning of alkaline soils, building industry, manufacture of value added chemicals/ products etc., TIFAC commissioned a Techno Market Survey on \"System Approach for Utilisation of Gypsum-A Mineral Resource\" . The report focusses on the present utilisation of this mineral resource in India for different purposes and explores the possibilities of its optimal utilisation for multifarious emerging and other uses as are in practice in other parts of the world. The present consumption of gypsum is mainly restricted to its use in cement, agriculture and a few industrial applications. Due to lack of proper approach towards utilisation of gypsum, a mineral resource of versatile utility, dumps of so called gypsum waste have been created and heavy expenditure on mining and long distance transportation is being incurred. The report takes a close look at the occurrences, reserves and production of gypsum, its available varieties along with chemical composition and mineralogy. It also deals with the different uses of gypsum in different industries in India and abroad, and finally details the various technologies for value added applications of gypsum.

Year of Publication : 1999

Table Of Contents : Executive Summary, Gypsum : The Material, Uses and substitutes of gypsum, Occurrences, reserves and production of gypsum, Present Consumption and future demand of gypsum, Scenario Abroad, Technologies for value added application, Critical observations and recommendations, List of Tables List of Annexures, List of Figures

  • Scope and Objective of the Study
  • Importance of the Topic
  • Methodology
  • Limitations
  • Findings & Analysis
  • Market Survey Response
  • Recommendations
  • Specific Recommendations and Impact, if Implemented

The Techno-Market survey "System approach for utilisation of Gypsum - a mineral resource" focuses on the present utilisation of this mineral resource in India for different purposes and to explore the possibilities of its optimal utilisation for multiferous emerging purpose and other uses as are in practice in other parts of the world. In addition, explores other uses suited to the socio-economical set up of the country. The present consumption of gypsum is mainly restricted to its use in cement, agriculture and a few industrial applications, where primarily the chemical properties of this mineral are utilised. The present approach of utilisation of gypsum has resulted in accummulation of huge quantities of by-product gypsum from industrial / marine sources on one hand and exploitation of high grade natural mineral gypsum resources on the other hand. Due to lack of proper approach towards utilisation of this mineral resource of versatile utilisty, dumps of so called "gypsum waste" have been created on one side and heavy expenditure on mining and long distance transportation is being incurred on the other side. For enlarging the field of utilisation of gypsum, its physical properties (non-conductivity, low specific gravity, sound absorption capacity, quick setting of calcined gypsum on hydration etc.) are to be further exploited to manufacture value added consumer items of mass consumption in building industry. Under present socio-economic setup of the country this mode of utilisation of the available gypsum resources will not only help to develope the gypsum industry and building industry in the country but also will help to solve :

  • Housing problems by providing cheap and good quality (light weight, heat & sound proof) pre-fabricated material and also the raw construction material.
  • Handling and disposal problems related with by-product varieties of gypsum.
  • Reclamation of millions of hectares of alkaline waste land for agriculture purpose.
  • To enhance the nitrogen use efficiency of urea fertiliser from 40% (present) to 80% by manufacturing gypsum coated urea.

Besides continuing exploitation of its chemical properties for optimal utilisation of this mineral resource, it could be used as a source of sulphur, the much needed commodity, being presently imported to meet the country's requirements.

These envisaged objectives could be achieved with implementation of only a few changes in the present approach in the adminstrative and mining taxation rules together with some financial incentives. A perceptible change in the housing and agriculture sector could be made by this important mineral. However, the required R & D work for its utilisation to manufacture much needed elemental sulphur / sulphuric acid can annually save foreign exchange to the tune of crores of rupees.

 

Scope and Objective of the Study

The scope and objective of the study as given by TIFAC is to address the following aspects in the context of the topic under study.

  • Relationship and the importance of the topic to the broad area to which it belongs.
  • The current status of the technology in the world and in India. Market (domestic and export) sizes and their potentialities.
  • Substitutes of gypsum as well as the materials for which it could optimally be used.
  • Assessment of technology, resource parameters such as energy, raw material, infrastructure etc. to arrive at preferred technology options available in the country.
  • Short term and long term economic aspects of preferred options along with their feasibilities.
  • Impact of preferred options by itself and its spin-offs.
  • Recommendations :
 
  • For implementation of preferred technology options - identifying critical inputs such as occurrence and availability of raw material, capital goods and human resources required and their, expected benefits etc.
  For R & D / technology development-identifying the requirements of inputs and expected benefits.
  • Action plan for implementation of recommendations alongwith identification of :
  • List of available technologies for Indian industry and
  • The agencies / groups / individuals for implementation.

Expected impact of recommendations; if implemented.

 

Importance of the Topic

In the country, the mineral gypsum is mostly used in the manufacture of cement, fertiliser, plaster of Paris, ceramics and distemper. Smaller quantity is used as soil conditioner, for carving and statuary purposes. While in other advanced countries large quantity of gypsum is used in the manufacture of materials for building construction industry.

Apart from the natural gypsum, marine gypsum is recovered as a by-product while manufacturing common salt from solar evaporation of sea water, and phosphogypsum as a by-product from phosphatic fertilizer plants. Nearly 1.54 tonnes of by-product gypsum is obtained per tonne of phosphoric acid produced. Marine gypsum comes from the coastal areas of Gujarat, Maharashtra and Tamil Nadu. While phospho-gypsum is the by-product of phosphatic fertilizer plants located in A.P., Gujarat, Maharashtra, Rajasthan and Kerala. Besides, India has huge resources of natural gypsum of the order of 1120 million tonnes, of which recoverable reserves are estimated at 237 million tonnes as on 1.4. 1995 (73 & 75). In general over 95% of the production of natural gypsum comes from Rajasthan, however during 1996-97 it accounted for more than 99% production of natural mineral gypsum in the country (2).

Due to increased production and use of by-product (both marine and phospho) gypsum, which is of comparitively higher purity than the natural gypsum and also due to implementation of the rationalisation scheme by Fertiliser Corporation of India (FCI), in its fertiliser factory at Sindri, the natural gypsum is facing a competation from the by-product gypsum. Consumption of natural gypsum is now mainly confined to the cement plants and to some extent for manufacture of Plaster of Paris. It has therefore, become necessary to explore alternative uses of gypsum such as conditioning of alkaline soil, building industry, manufacture of value added chemicals / products etc. Annual surplus production of the order of 2 to 3 million tonnes of gypsum from industrial / marine sources need to be optimally utilised. To achieve the desired results not only R & D work is required in the field of by-product gypsum but the existing system approach towards mining, marketing and utilisation of this mineral needs to be reviewed and modified in the interest of the nation.

 

Methodology

The Techno-Market Survey was conducted through extensive literature survey on the subject relating to the occurrences, reserves, distribution, production, marketing and consumption of gypsum in India and the world over and the constraints in the system approach for its proper utilisation. The various possibilities of its utilisation against actual use in the industries have been explored to find out that which matter it can substitute and by which minerals or matter it could be substituted to establish the optimal utility of this valuable mineral resource. Present technological status of mining i.e. production, processing and consumption scenario in India as well as in world has been synthesised and evaluated in the light of ongoing R & D work towards optimum utilisation of the resources of gypsum in the country. This desk work was followed by -

  • Mail survey through structured and open ended questionnaires
    (Annexure -A). Efforts were made to get back the replies through reminders and even telephonic discussion, wherever required.
    The questionnaires covered all possible segments viz. mining, processing, marketing and consuming agencies of gypsum in private and Govt. sectors, Research Institutes and other related organisations in India. A number of foreign agencies were also contacted. Annexure-B gives the list of agencies contacted.
  • Personal interviews and discussions were held with several persons to gather further informations and clarifications.
  • Discussions with the experts in various field of gypsum were held and obtained literature on request.
  • Compilation, analyses and synthesis of data was carried out in accordance with the guideline of TIFAC.

The draft report was be finalised in accordance with the comments and suggestions, that would be received from TIFAC.

 

Limitations

During the survey a few difficulties were experienced in collecting informations particularly on detailed aspects of technology and economics. Only a few organisations / individuals were willing to part with the detailed information. However, some insight could be obtained during personal meetings and persuasions. Thus, the report may be read in conjunction with the following limitations :

  • The study is based on published literature, mail survey, a limited number of personal visits and interviews.
  • No interview could be possible with foreign experts. The details of technical and economic parameters are limited to the extent of information that could be gathered during the survey.
  • The informations of world scenario and evaluation thereof is primarily based upon the published literature.
  • the informations on commercial aspects of the technoloigies were provided only by a few.

 

Findings & Analysis

Gypsum, a versatile industrial mineral, is a high bulk and low cost material. In India the present trends of its consumption are related mostly towards exploitation of the chemical properties of the gypsum, where as its physical properties (having even much more potential for its commercial utility) remained marginally utilised. In contrast to these trends of usage of gypsum, the advanced countries like America and European countries are using gypsum mainly for the building construction materials. It has been established that gypsum is one of the important industrial minerals having multiple uses, mainly in building and construction activities. Its latest use in India, however, has started recently for the manufacture of wallboards, block, etc. which is envisaged to be the most potential market for gypsum. The use of gypsum as soil conditioner / reclaming material is also gaining importance mainly in some of the northern states. The other prospective use of gypsum is its use as raw material in the manufacture of sulphuric acid, where cement clinker is obtained as a by product. The present techno-market survey evaluated the present status of the demand and supply and resources situation and future projection for 2000, 2005 and 2010 A.D.

In general there was no problem in the mining of surface gypsum deposits in the country. However, due to envisaged higher cost of production of this low cost material, the deep seated gypsum/anhydrite deposits located in Nagaur district of Rajasthan are not mined at present.

In general cement industry is not facing any problem with regard to the quality of gypsum supplies. However, since maximum production of gypsum (about 95%) comes from Rajasthan, transportation cost is prohibitively high for many cement manufacturing units located elsewhere in the country.

Natural gypsum and by-product gypsum (phospho-gypsum and marine-gypsum) are mostly used in the manufacture of plaster of Paris. The drawback in this utilisation was reported to be that the quality of gypsum supplied was not uniformly maintained. The freight charges on gypsum were also quite high.

There was a good demand for agriculture grade gypsum in the states of Uttar Pradesh, Haryana and Punjab. But due to high cost of freight charges and non availability of subsidy from Govt., reclamation of soil programme could not be taken-up on large scale in the country. The prices of agricultural grade gypsum were increased quite frequently by the producers. Gypsum from J & K is also suitable for reclamation of soils, but transportation cost and other logistic support from Govt. are prohibitive. Even phospho and marine gypsum could be used effectively for reclamation of alkaline soils.

The Fertilizer Corporation of India (F.C.I.) is one of the important producers of gypsum in the country operating about 14 mines in Rajasthan itself. Production from all these mines, except Ulttaralai and Kavas mines are permitted for sales for local consumptions and for captive consumption in fertilizer plants at Sindri only. However, the company is not permitted to sell the gypsum mined from these mines to anyother industries (cement, wall boards, blocks etc.) by the State Govt. of Rajasthan. Thus, inspite of having capacity and capabilities to increase the production of gypsum, FCI has not been able to raise the production. However, the State Govt. has allowed FCI to sell the gypsum mined from Uttaralai and Kavas mines for cement consumption since these two mines were located in the remote areas of Barmer district.

The other two producers of gypsum viz. RSMDC Ltd. and RSMM Ltd. were facing problem in marketing their marginal grade gypsum for either remote location of mines or irregular production due to pocketing nature of gypsum deposits.

 

Market Survey Response

The response to market survey was quite encouraging. We got about 56% response from Indian organisations and about 37% response from foreign agencies (including embassies). It includes the response in reply to our reminders and also collection of information during personal meetings and interviews.

The informations regarding technologies and commercial aspects was provided only by a few. Particularly, the commercial aspects of the plaster boards and its accessories which has been developed at laboratory scale and is being used by only few on commercial scale. Most of the respondents have sent published literature and literature on R & D work under taken.

 

Recommendations

Inspite of having huge resources and surplus production of gypsum, there are some problems in the system of approach for its utilisation causing under utilisation of this mineral resource of versatile utility. As a result of which more than 12 million tonnes of gypsum has been accumulated (major share being of phsophogypsum) till date, causing not only handling and utilisation problems, but is also a perpetual cause of environmental hazard. At the same time the irregular production of natural mineral gypsum of comparatively inferior grade, requring beneficiation before its utilisation in many industries, faces marketing problems. With present trends of increase in consumption of gypsum in the cement industry alone, the production of gypsum will fall short of its demand by 2000 A.D. Thus, in order to enhance the availability of the gypsum to the gorwing need of the industry following recommendations are made.

  • Further, research and development work should be carried out to make use of phospho-gypsum for various purposes.
  • There should be no restriction on any mining organisation to sell the mined out gypsum to any manufacturing unit for its utilisation anywhere in the country. The leasee agency should be allowed to use the mined gypsum for any purpose in addition to the purpose for which it was taken on lease.
  • As gypsum is a low cost material and requires bulk transportation, hence to avoid long distance ransportation, the bulk consuming industries should be developed around the gypsum deposits or the by-product gypsum producing industrial units.
  • The entrepreneurs should be encouraged to use the already developed technologies for utilisation of gypsum in manufacturing building / construction material.
  • Utilisation of gypsum in agriculture sector as soil conditioner has a large scope, as over 86 million hectares of salt affected land (including saline and alkali soils) exists and the alkaline land could be reclaimed for agriculture purposes - by treating it with gypsum.
  • R & D work should be carried out to manufacture sulphuric acid from gypsum in India in the light of the technologies developed in the country as well as elsewhere (France & German) in the world.
  • Planing should be carried out to mine the sub-surface Nagaur gypsum of Rajasthan and Doda gypsum deposits of J & K, so that by the time the accumulated 12 million tonnes of phospho-gypsum is exhasted the proposed mining may commence say around 2005 A.D.

 

Specific Recommendations and Impact, if Implemented

  • Appropriate modifications in the administrative and legislative rules and regulations governing mining, marketing and consumption of the mined out or produced (by-product) gypsum be made, so that it should not hinder the processes of utilising this commodity in best possible way.
  • Use of by-product gypsum, particularly phospho-gypsum , should be made compulsory by the Govt. for those applications / uses where it could be used without any problems or harmfull effects on the quality of the finished products.
  • The already developed techniques of beneficiation and utilisation of by-product gypsum by different R & D Institutes / Organisation should be commercialised even by providing initially financial subsidies and other incentives to the industrial entrepreneurs.
  • R & D work on scrubber gypsum or flue gas desulphurisation gypsum (FGD gypsum) to reduce its chloride contents from 0.13%-2.48% to 0.002% - 0.03%.
  • Gypsum should be used to manufacture value added construction / building material of mass consumption.
  • R & D work on gypsum to manufacture sulphur / sulphuric acid should be vigorously persued, so that it could be commercially used to manufacture sulphur / sulphuric acid and portland cement as complementary by-product material. It will help the nation to save atleast few hundrends of crores of rupees in foreign exchange, presently being spent in importing sulphur to manufacture sulphuric acid.
  • Gypsum coated urea should be manufactured on large scale, as it enhances the nitrogen use efficiency of the urea.
  • Incentives should be given by the government to farmers to use gypsum for reclamation of alkaline waste lands. This will help to enhance the agriculture production of the country.
  • India has sizable accumulation of phospho-gypsum (over 12 million tonnes at the end of 1977) at the phosphoric acid plants located near the ports of Visakhapatnam, Tuticorin, Madras, Haldia, Bombay etc., besides, other interior places as Baroda in Gujarat, Udyogmandal in Kerala etc. The surplus phospho-gypsum as such or after benefication should be exported to earn the much needed foreign exchange for the country. There is a wide scope of exporting the gypsum from port places to Bangladesh, U.A.E., Japan, Republic of Korea, Malaysia, Saudi Arabia, Taiwan, Hongkong, Singapore, Omman etc.
  • India has ample known reserves of natural gypsum and resources of by-product gypsum to meet the present internal demand and the increased future demand, provided a careful approach is made to exploit the available technologies for its optimal utilisation.