There are two types of systems of open pan boiling process in India. North India and Gujarat (Here), multi pan boiling system is used. In Maharashtra and south India, single pan boiling system is used.

In multi span system, generally there are 4 pans, 1.8 mt dia and thickness of spherical bottom plate is 30mm, 25mm, 20mm and 16mmor 12 mm. So very thick plates are used. Plus such heavy plates are shaped spherical little bit, not flat bottom. Fresh juice is poured in the first pan of minimum thickness, say 16mm, then after boiling considerably, juice is transferred in second pan of 20mm thick bottom, then from there, concentrated juice is transferred in third pan of 25mm thick bottom and lastly it is transferred in to last pan of 30mm thick bottom where final jaggery is vigorously heated and then transferred to cooling pan. All 4 pans are arranged in line and underneath furnace gives heat of bagasse firing maximum to 4th pan, then flue gases travel under 3rd pan, then under second pan and then under first pan and then goes to chimney.

In a single pan system, one there is only one boiling pan of at least 3 mt dia with flat bottom of hardly 3 mm thick. After preparing jaggery , it is transferred to cooling pan and new juice is taken in the same pan. it takes about 2 hours to prepare jaggery in this batch type process.

There is a lot of confusion about which system is better, single pan or multi pan. Both systems have their strong advocates. But I have come to conclusion that single pan is far cheaper, simpler and jaggery quality is same in both systems. So to employ multi pan is sheer wastage of money.

So I have offered you single pan system.
for producing free energy from the waste heat going to chimney, i have thought out 2 different boiler designs. One is to put water tube mono tube coil boiler in the chimney which must give you steam to drive steam engine to run sugarcane crusher. In this system, continuous supply of dry steam may become problem. expert and experienced boiler engineer having good experience in mono tube boiler is required. There is no storage of steam and no storage of water. Fresh water is continuously supplied which must deliver continuous supply of steam. This is too difficult. So 2 separate drums of water and steam must be connected before and after coil ends. Then also, it will be difficult to maintain balance.

Another system is to install a Babcock & Wilcox type boiler of bundle of inclined straight tubes all parallel and connect them by headers in underground trench of flue gases from furnace to chimney. This boiler is somewhat similar to Babcock & Wilcox boilers widely used in power houses. The main header of steam drum will remain above the ground level and two pipes will connect the boiler remaining under ground in the trench. This boiler will be easier to operate by common people. So I have offered it to you. However if you are interested in chimney coil mono tube boiler, i can supply the coil also.

1. To make best quality jaggery (GUR), soil condition should have 7 PH. If PH is less, soil can be reclaimed and improved by adding gypsum in the soil.  Soil should be a little granular so that water may be drained to avoid water logging.  It should not be salty and sour.
2. Soft and straight sugarcane having less fiber content gives better quality jaggery. Fast maturing sugarcane gives better quality jaggery. Big sugar factories invariably have laboratory which can measure all the ingredients. So laboratory chemist should be contacted to get better knowledge and information. Difference in recovery in freshly harvested and crushed sugarcane and after one day crushing can be measured in laboratory.
3. After harvesting the sugarcane, it should be protected from sunshine. Harvested sugarcane remaining under sunshine gives less recovery of juice. So freshly harvested sugarcane must be crushed at the earliest possible. If you crush after 24 hours or 48 hours, recovery will be less and quality of jaggery will deteriorate. To protect from sunshine, harvested sugarcane should be under the temporary shed or it should be covered by tarpaulin. If severe sunshine is there, water should be sprinkled on the sugarcane heap.
4. Quality of the jaggery mainly depends on juice clarification.If juice is  properly clarified quality of the jaggery will be light color , granular, hard and more nutritious. It  can not absorb moisture. So in the summer, such a jaggery will not become soft, pasty and liquid.
5. All types of jaggery chemicals available in the market make the jaggery attractive for a short time. But the process of spoiling the quality will be accelerated. So on the whole, it is harmful for farmers and also harmful to health. Those who want to store jaggery  for 2 -3 months, the jaggery with chemicals will deteriorate in quality and hence with fetch less price to farmers. So avoid chemicals.   Using lime is not harmful.  So it can be used in proper quantity. If you use less lime so that PH remains less than 7, then jaggery becomes soft and sometime pasty. And if you use more lime so that PH is more than 7, jaggery becomes too hard and black. So every farmer must learn how to measure PH. It is not expensive at all. If PH is maintained at 7 correctly, jaggery will not melt in summer to make its black slurry.
6. Government of India has established Jaggery Research Institute in Kolhapur. Their research says that if jaggery is boiled up to 118 degree C, jaggery becomes of best quality granular and crystalline. Generally farmers boil the jaggery up to 108 degree C. Then they cool it in cooling pan. This is wrong. It should be boiled up to 118 Degree C so that moisture content will be reduced after cooling the jaggery. To measure the temperature of 118 degree C., electronic digital temperature indicator is available in the market which may cost about Rs.500/-. It works on a small battery. It displays figures of temperature directly.
7. To make the granular powder of the jaggery, it should be boiled up to 118 degree C. and then it should be cooled very fast by industrial fans. You can also use  cooling pan of iron sheet jacketed at the bottom and pass cool water underneath. So jaggery will be cooled very fast. You can use both the system at a time. Granular jaggery can be used everywhere, where sugar is used. So it is a better  alternative of sugar. So it fetches very high price. So every clever farmer should learn how to make granular jaggery. For uniform size of granules, it should be sieved. You can see many youtube videos on internet  for production of granular jaggery.  Please note that as poisonous  sulpher is used in sugar making, millions of people are searching for alternative of  sugar. So granular jaggery powder is the real alternative of sugar.
8. There is wide spread experience that jaggery stored in monsoon time becomes slack and black liquid starts flowing from it. To avoid this, moisture content in jaggery must be less than 6 %. The building in which jaggery is stored should get dry air. If it does not get air, jaggery spoils. Moisture content measuring instruments are also available in the market. When jaggery is boiled and cooled, moisture content is 10 to 12%. In a few days jaggery is further dried by atmosphere and moisture content should be reduced by 6 %. It means that weight of the jaggery should be reduced proportionately by 6 %.
9. If you want to pack the jaggery in a metal or plastic container, then it is essential that before packing moisture content must be less than 6%. Otherwise it will be spoiled. The best packing is not to have any packing and solid shape round cone or rectangular shape will be better because it will get air from all around to reduce the moisture content. If packed in a container, it will not get air and it may spoil. If packing is porous with many holes all around to get air, it will be ideal.
10. If jaggery is stored in a warehouse, it should be ensured that it may not attract moisture from floor or from walls.