Producer Gas Plants

6.0  Ecological and Safety features

The basic ecological feature of extended shaft gasifiers are :

     a)  Gasifiers are operation friendly.

     The new generation producer is easy to operate and with proper instrumentation the control of various parameters like change in the coal throughput, addition of air for a controlled blast saturation temperature(BST), maintaining the mobility of coal bed and ash discharge system, regulating the heat demand through BST controller which is cascaded with air flow are all very simple with proper automation and instrumentation, less physical labour will be involved for the operators.

     b)  Safety Aspects :

 The gasifiers are extremely safe to operate. With proper sealing arrangement of the coal feeding system, poke holes and ash bowl, there is absolutely no gas leakage to the surroundings nor any emissions of particulate matters. Against any over pressure of the gasifier, water seals are provided at desired locations. High and low level alarms are provided on the jacket-boiler steam drum 

     c)  Gasifiers are eco-friendly :

Extended shaft  gasifier of Engineering services are fairly pollution free. There is no     gassious or liquid effluent. Heat radiation loss is well guarded with the help of  water cooling jacket and glass wool insulation on the bottom seal and refractory insulation in the extended shaft portion, so far as liquid effluent is concern,0.5 to 1.5 MT light tar per day is collected in the mixing cum washing chamber. This is in a highly fluid state due to ingress of stripped volatile matter of coal and its viscosity is almost similar to furnace oil. As such, it can be used as CTF, with fuel oil or in the oil burner along at a high price. The phenol water collected in the mixing chamber is circulated through the washing chamber for washing and cooling the PG gas alternatively phenol water is sprinkled on the coal. The only solid discharge is ash granular which non-toxic. This can be used in cement plant or for road repair or filling of low lying areas. 
 

d) Other PCB aspects like noise level(below 60 DB), chemicals substance control physicals hazards and agronomical aspects are well taken care off to the ultimate satisfaction of pollution control Board and the work force.

5. Special safety geatures have been opted for the ETP and The booster. The ETP safety logic as prescribed by the ETP manufacturer is accommodated in the Main PLC program. Similarly that of Booster station. Special pressure monitors are placed at a distance of every 20 meters on the pipeline originating from the ETP and destined to Gas boosters. This is to prevent zero pressure crossing the red limit towards the ETP. Complete shutdown  of the ETP and the booster occurs if the safety limit is crossed.